Researchers from University of California San Diego and University of Freiburg in Germany have found that switching to a vegan diet for just one month can alter the body’s epigenetic landscape in ways associated with reduced inflammation and biological aging. In a randomised clinical trial, participants assigned to a vegan diet vs a meat-rich diet showed changes in DNA methylation – a biological process that regulates whether genes are more or less active – that were linked to immune function, metabolism and cancer-related pathways. The findings, published in the journal MedComm, suggest that dietary choices can rapidly influence molecular processes associated with long-term health.
“Our genes are not our destiny,” said Jerome Mertens, PhD, associate professor of neurosciences at UC San Diego School of Medicine and co-senior author of the study. “The remarkable finding isn’t simply that one diet outperformed another. It’s that the epigenome responded measurably in just four weeks, showing that our biology is far more dynamic – and responsive to everyday choices – than we often assume.”
Diet has long been linked to the risk of chronic diseases such as cardiovascular disease, diabetes and certain cancers. Yet scientists have only begun to understand how food influences the epigenome – the layer of chemical modifications that helps determine which genes are turned on or off without changing the underlying DNA sequence.
To explore these effects, researchers analysed genome-wide DNA methylation patterns in blood samples from 48 healthy adults who participated in a randomized dietary intervention. After following the same standardized diet for one week, participants were randomly assigned to either a vegan diet or a meat-rich diet for one month. Both diets were designed to provide similar calorie intake, allowing researchers to isolate the effects of diet composition rather than weight loss.
The team examined more than 800 000 methylation sites across the genome before and after the intervention. Rather than looking for changes in individual genes alone, the researchers focused on broader biological patterns that changed in response to diet.
The researchers also found evidence that the vegan diet shifted the immune system toward a less inflammatory state. DNA methylation analyses predicted lower proportions of neutrophils – immune cells that drive inflammation – and higher proportions of CD4 T cells, which help regulate immune responses. Those predictions closely matched blood cell measurements collected during the original clinical trial.
“Our genes are not our destiny. The remarkable finding isn’t simply that one diet outperformed another. It’s that the epigenome responded measurably in just four weeks, showing that our biology is far more dynamic – and responsive to everyday choices – than we often assume.”
Jerome Mertens, PhD, associate professor of neurosciences at UC San Diego School of Medicine and co-senior author of the study
“That agreement told us we weren’t just seeing changes on a computer screen — we were detecting real and meaningful biological changes,” said Lukas Karbacher, UC San Diego School of Medicine neuroscience graduate student and first author of the study.
The findings build on earlier evidence that plant-based diets can influence immune function while providing additional insight into the molecular changes that accompany those effects.
In addition to immune signals, the researchers found that the vegan diet was associated with increased promoter methylation in genes involved in several cancer-related and cell growth pathways. Increased promoter methylation can reduce the activity of genes within these pathways, suggesting the diet may influence cellular processes involved in growth and proliferation. The researchers also observed changes consistent with reduced activity in lipid metabolism pathways and increased activity in pathways related to insulin signaling, DNA repair and cellular stress responses.
Perhaps the most striking finding concerned biological aging itself. For this, the researchers examined biological age using epigenetic clocks – a mathematical biomarker that estimates a person’s biological age based on DNA methylation patterns rather than years lived. Two clocks designed to predict health outcomes suggested participants following the vegan diet experienced a deceleration in biological aging over the one-month study period. A third clock, optimised to predict chronological age rather than health outcomes, showed a different pattern, highlighting that epigenetic clocks measure different aspects of aging.
“These findings reinforce the idea that not all measures of biological aging capture the same biology,” said Mertens. “The clocks associated with disease risk and overall health consistently pointed in the same direction, suggesting the dietary changes were influencing pathways tied to health rather than simply the passage of time.”
The researchers caution that the study was relatively small, involving 48 healthy adults, and lasted only one month. Because the observed DNA methylation changes were modest and spread across hundreds of thousands of sites in the genome, larger and longer studies will be needed to confirm the findings and determine whether the molecular changes translate into measurable reductions in disease risk.
While the findings do not demonstrate that a vegan diet prevents cancer or reverses aging, they provide new insight into how dietary choices may rapidly influence the biological processes that underlie inflammation and age-related disease.
“Our study adds to growing evidence that nutrition can shape biology at the molecular level,” said Max Storz, MD, from University of Freiburg Medical Center and co-senior author of the study. “The next step is to understand whether these epigenetic changes persist over time and whether they translate into meaningful improvements in long-term health. That will require larger clinical studies, but these findings provide an important foundation.” Storz also stressed that the findings are not the result of reduced calories, but rather a matter of diet composition.
Environmental Health Practitioners regularly test drinking and recreational water to detect contamination and help prevent diseases such as cholera and typhoid. (Photo: Unsplash)
By Christina Pitt for Spotlight
From inspecting spaza shops to monitoring water quality, Environmental Health Practitioners help prevent disease before outbreaks occur. A Public Protector investigation reveals why Gauteng municipalities are struggling to deliver these essential public health services. The investigation also helps clarify what is at stake in South Africa’s local government elections in November.
Environmental Health Practitioners (EHPs) operate as the public health system’s early warning system. They are responsible for identifying and managing environmental health risks before they become public health emergencies.
Whether inspecting food premises, monitoring water quality or investigating environmental health hazards, their work is designed to avert illness. These preventative functions form part of the municipal health services that local governments are required by law to provide and what will be at stake in the local government elections in November.
The importance of these largely invisible health services came into sharp focus when Public Protector Advocate Kholeka Gcaleka released preliminary findings of an investigation into Gauteng’s food safety system on 17 July 2026.
The probe followed a series of food poisoning incidents involving children in 2024. Among the most high-profile was the death of six children who allegedly consumed contaminated food bought from a spaza shop in Naledi, Soweto.
Rather than focusing only on the poisoning incidents themselves, the Public Protector’s office examined whether Gauteng’s municipalities were adequately delivering the municipal health services responsible for regulating food safety and hygiene standards in the informal business sector.
As the local government elections draw closer, we unpack how municipalities use environmental health services to prevent harm and protect public health, and find out what happens when that system comes under strain.
To start with, we need to understand what municipal health services are, the responsibilities assigned to municipalities by law, and how those services are intended to function.
What are municipal health services?
Food safety is just one of many municipal health services.
Professor Jaap de Visser, National Research Chair in Multilevel Government, Law and Development at the Dullah Omar Institute at the University of the Western Cape, points to the National Health Act for the full list.
The Act defines municipal health services by naming nine preventative functions, including food control, water quality monitoring, waste management, vector control, and environmental pollution control.
For example, EHPs routinely collect drinking and recreational water samples for laboratory testing to detect contamination and reduce the risk of waterborne diseases such as cholera and typhoid.
This table below illustrates the key functions they perform to prevent disease before people become ill.
The National Environmental Health Norms and Standards requires EHPs to adopt a preventative, risk-management approach. In practice, this means rather than inspecting every premises equally, they prioritise activities and facilities that pose the greatest risk to public health.
“Higher-risk premises, for example, those handling high-risk foods, with a history of non-compliance, would be inspected more frequently and receive more intensive oversight,” explained National Department of Health spokesperson Foster Mohale. “Conversely, lower-risk premises with a strong record of compliance may be inspected less frequently, allowing EHP resources to be directed where they are most needed.”
EHPs also have enforcement powers when they identify breaches of prescribed health standards. They can issue compliance notices, requiring owners or operators to correct a problem within a specified period.
Their work also includes routine inspections, environmental health surveillance, investigating complaints, and educating communities and businesses.
Which municipality is responsible for delivering these services depends on where you live.
In metropolitan municipalities such as Johannesburg, Tshwane and Ekurhuleni, the municipality is responsible for providing municipal health services within its boundaries.
In non-metropolitan areas, the Municipal Structures Act provides that district municipalities are generally responsible, while local municipalities perform the function only where they have been authorised to do so in terms of the Act.
Although municipalities deliver these services, the National Health Act requires them to work as part of a coordinated health system. It establishes District Health Councils to support coordination between national, provincial and local government.
According to Mohale, municipal health services are intended to function as an integrated three-tier system in which national, provincial and district environmental health units work together to deliver municipal health services.
“Working together, these structures are intended to create a coordinated system in which national government sets the policy and regulatory framework, provinces provide oversight and technical support, and district structures coordinate and strengthen implementation at municipal level,” he said.
Food safety provides a useful example of how that system operates in practice.
From farm to fork
Food microbiologist and food safety expert Professor Lucia Anelich says South Africa follows a “farm to fork” approach, with different institutions responsible for different stages of the food chain.
The Department of Agriculture oversees food safety at the production stage by regulating agricultural pesticides and veterinary medicines as well as food safety in abattoirs.
Once food enters the retail environment, the Department of Health, through municipal EHPs, is responsible for inspecting food premises, checking how food is prepared and enforcing food safety requirements.
The Department of Trade, Industry and Competition provides an additional layer of oversight by inspecting certain imported food products at ports of entry, overseeing product recalls and investigating consumer complaints.
When food contamination is suspected, those responsibilities overlap as the relevant authorities work together to trace the source, remove contaminated products, and prevent further illness. The agencies involved depend on where the suspected source lies within the food chain.
The Public Protector’s Gauteng food safety investigation examined whether the preventative systems intended to identify and manage these risks before outbreaks occurred were functioning as intended.
A break in the chain
The level of coordination required for food safety is not the type of thing that happens by chance.
That is why District Health Councils are tasked with strengthening planning, oversight and coordination between national, provincial and local government.
According to Mohale, these structures are intended to provide a forum for regular engagement between stakeholders, monitor the implementation of environmental health programmes and “ensure that food safety risks are identified and managed proactively.”
Yet, the Public Protector identified a significant weakness in Gauteng’s food safety system with the absence of functioning District Health Councils.
Without them, coordination between different spheres of government becomes more difficult, weakening oversight, planning, and the implementation of municipal health services.
Delivering these services also depends on whether municipalities have enough EHPs to carry out routine inspections.
EHP employment gaps
One of the Public Protector’s clearest findings was that Gauteng municipalities lack sufficient EHPs to carry out their statutory functions.
As of October 2025, every municipality fell short of the World Health Organisation (WHO) and the National Environmental Health Norms and Standards benchmark of one EHP for every 10 000 people.
Johannesburg had the largest absolute number of EHPs, with 240 practitioners serving a population of 4.8 million people. This gave it a ratio of one EHP for every 20 000 people, or 50% of the recommended benchmark.
Meanwhile, Ekurhuleni and Tshwane had fewer than one-quarter of the recommended number of EHPs.
According to City of Johannesburg spokesperson Nthatisi Modingoane, its current staffing complement is 213 EHPs, with eight funded vacancies. Despite ongoing recruitment, the City estimates that each EHP is still responsible for about 28 000 residents — almost three times the benchmark.
City of Ekurhuleni spokesperson Zweli Dlamini said the municipality now employs 98 EHPs, up from 94 during the Public Protector’s investigation. However, he acknowledged that the municipality still has a shortage of 309 EHP posts, leaving it well below the recommended staffing benchmark.
The City of Tshwane did not respond to Spotlight’s requests for updated staffing figures.
“The entire province is functioning at less than a third of the required EHP staffing capacity,” Gcaleka said about her findings, warning that the shortage threatens equitable access to environmental health services.
Anelich explained that staffing shortages are compounded by the breadth of EHPs’ responsibilities.
“EHPs are trained broadly, including water quality control and pollution monitoring — not only food,” she said.
“These people have multiple roles to play, which makes it very difficult for the system. We should have EHPs dedicated to food safety so municipalities can regulate food safety more effectively, particularly in the informal sector.”
The National Environmental Health Norms and Standards require EHPs to inspect high-risk food premises at least once every quarter. Maintaining those inspection frequencies becomes increasingly difficult when each practitioner is responsible for far more people than the recommended benchmark.
The capacity constraints extended beyond municipalities. The Public Protector found that the Department of Agriculture had filled only 27 inspector posts, which it described as insufficient to regulate agricultural pesticides effectively, weakening another part of the food safety chain.
But increasing staffing capacity depends on whether municipalities have the financial resources to create and sustain these posts.
Money troubles
The Public Protector also found that municipalities were not allocating enough funding to municipal health services, limiting their ability to recruit and retain EHPs.
Municipal health services are funded primarily through the local government equitable share. This is money allocated by National Treasury and transferred to municipalities to help provide basic services. Municipalities also use revenue from rates and taxes.
Because the equitable share is an unconditional grant, municipal councils decide how much funding is allocated to environmental health alongside their other constitutional responsibilities.
Although the National Department of Health is not responsible for funding municipal health services or employing EHPs, Mohale said it continues to support initiatives aimed at helping municipalities recruit, retain and train EHPs.
He also said the department engages with National Treasury and the Department of Cooperative Governance and Traditional Affairs to prioritise the appointment of EHPs and address staffing shortages.
The human cost
These system weaknesses had visible consequences on the ground. During blitz inspections cited by the Public Protector, EHPs repeatedly identified expired food, unlabelled products, poor hygiene, rodent infestations, and unsafe storage practices.
The Public Protector also found low levels of compliance with spaza shop licensing requirements.
Only 5% of spaza shops in Ekurhuleni were licensed or permitted, compared with 14% in Johannesburg and 30% in Tshwane, according to Gcaleka’s speaking notes. Across Gauteng, the compliance rate was 28%, meaning that for every licensed spaza shop, almost three were operating without the required license or permit.
“So many spaza shops aren’t licensed, so EHPs don’t even know where to look,” Anelich said.
“We can send EHPs into informal settlements to look for them, but that’s not a great use of resources that are already stretched.”
She also said the deaths highlighted what can happen when food safety systems fail. Adding that South Africa’s burden of foodborne disease remains poorly documented, making it difficult to understand the full scale of the problem.
A systemic failure
The Public Protector found that the problems extended beyond individual incidents.
In her speaking notes, Gcaleka says that the underlying governance weaknesses, severe staffing shortages, inadequate funding for municipal health services and capacity constraints in other parts of the food safety system were “not incidental, but systemic and far-reaching”.
She therefore made the preliminary finding that Johannesburg, Ekurhuleni, Tshwane, Sedibeng and West Rand had failed to properly enforce food safety and hygiene standards in the informal food sector.
As voters prepare to elect new local governments in November, the findings highlight a core municipal responsibility: preventing public health risks before they become public health crises.
A new study from The Wistar Institute has uncovered an unexpected link between fructose and the spread of an aggressive form of ovarian cancer. Published in Nature Aging, the study found that cancer cells not killed by chemotherapy send signals to neighbouring tumour cells, driving metastasis. The researchers identified fructose as a key messenger in this process, revealing a previously unrecognised way that treatment-surviving cancer cells may promote metastasis.
“Some cancer cells that survive chemotherapy aren’t dividing anymore, but they’re still biologically active,” said Aidan Cole, PhD, a postdoctoral fellow in the lab of Katherine Aird, PhD, at The Wistar Institute and first author on the study. “Instead, they continue to release molecules that send signals to nearby cells. Our study is among the first to show that a nutrient – in this case, fructose – can act as one of those signals.”
Ovarian cancer is treated almost universally with platinum-based chemotherapy, and many patients respond well at first. However, the disease recurs in most patients and almost always spreads through the abdominal cavity. That spread, called metastasis, accounts for roughly 90% of deaths from the disease.
Prior research has suggested that cancer cells not killed by chemotherapy play a role in recurrence in part through the ability of these cells to release a complex mix of signalling molecules. Cole and his colleagues began their research by designing a unique experiment: they collected the molecules released by chemotherapy-surviving cells and found these factors alone could significantly increase the spread of cancer cells.
“As far as we know, this is the first time anyone has shown, in a preclinical model rather than just a dish, that it’s the molecules these cells release – not the cells themselves – that drive the cancer’s spread,” said Cole.
That finding sent the team looking for what was being released that caused the cancer cells to spread. Fructose, it turned out, was being made by the surviving cells and sent as the signal for increased spread. Even more interesting, they found that without chemotherapy treatment, consuming the high levels of fructose found in sugary drinks can also signal cancer to spread. The fructose finding is especially compelling because it raises the possibility that simple dietary changes could help shape how cancer progresses. This is particularly important given the prevalence of fructose consumption in the United States, with high fructose corn syrup accounting for ~8-20% of the daily caloric intake in some individuals. Unlike many cancer risk factors outside of patient control, fructose consumption can be modified by dietary choices. While the effectiveness of limiting fructose intake hasn’t yet been tested directly in patients, the study raises the possibility that nutrition could influence cancer progression in previously unrecognised ways.
The researchers next aimed to understand why fructose increases cancer cell spread. Through a variety of large-scale analytical techniques, including the use of a CRISPR screen, they discovered that fructose suppresses cholesterol within the neighbouring cells. Cholesterol is important for cells to stick to each other like a biological glue, so decreased cholesterol allows cells to more easily escape and spread.
The finding that fructose lowers cholesterol production has important clinical implications. Statins, which are taken by 39 million people in the United States, lower cholesterol production. The team found that statins alone decreased the glue between cells to promote escape. The research team is now examining whether these medications could be interfering with the effects of chemotherapy – though they stress this isn’t a reason for patients to stop taking them.
“We haven’t tested this effect in patients yet, but it raises questions about combining cholesterol-lowering drugs with chemotherapy, especially since ovarian cancer is most common in postmenopausal women who are often already on statins,” said Katherine Aird, PhD, professor and co-leader of the Molecular and Cellular Oncogenesis Program in the Ellen and Ronald Caplan Cancer Center at The Wistar Institute, and senior author of the study.
The researchers are also looking into how this mechanism might extend beyond ovarian cancer.
“We think other cancers that spread within the torso – pancreatic, colon, liver – could behave similarly. We can’t call it universal yet, but we think the effects are not just limited to ovarian cancer,” said Aird.
She and Cole have already started designing follow-up experiments to test the reproducibility of their findings in a variety of other cancer types.
Cambridge researchers have shown how commonly-used sweeteners slow the growth of certain gut bacteria. Isosteviol – a compound derived from stevia (a common sweetener) – when combined with the anti-depressant duloxetine significantly impaired two important gut bacteria linked to regulating blood sugar and gut health and may affect the body’s immune responses.
Sweeteners are often marketed as metabolically neutral, but our study challenges this idea
Sonja Blasche
The scientists say more research is needed to understand the real-world health impacts of this laboratory study, one of the first to assess the direct impact of sweeteners on gut bacteria, particularly when they are combined with other substances.
Sweeteners are widely used in a range of food and drinks, including soft drinks, sweets, desserts, snacks and cereals. While marketed as healthier alternatives to sugar, there is increasing evidence of links to diseases such as type 2 diabetes, obesity and cancer.
Despite their pervasive use, there have been very few studies that look at the direct interactions between sweeteners and gut bacteria – the vast community of microorganisms that live in the digestive tract and play a crucial role in keeping our bodies healthy.
Professor Kiran Patil from the Medical Research Council (MRC) Toxicology Unit at the University of Cambridge said: “Most of what we know about the potential impact of sweeteners on our health comes from animal research or from population studies. While these studies have indicated involvement of the microbiome in mediating the effect of sweeteners, it’s difficult to know how sweeteners act in the body – is it through direct interactions with our gut bacteria?”
“Answering this is further complicated by the fact that we rarely ever take sweeteners by themselves – we take them with drinks, in snacks, or even in medication to mask bitterness,” added Dr Sonja Blasche, a lead author of the study, also the MRC Toxicology Unit.
In research published in Molecular Systems Biology, Dr Blasche and colleagues looked at how artificial and low‑calorie sweeteners affect the bacteria living in our gut, and how these effects change when sweeteners are consumed together with other common substances such as caffeine, flavourings or medicines.
The researchers grew each of 25 gut bacterial species – including beneficial, neutral, and potentially harmful bacteria – in the lab. They then exposed each culture individually to 39 common, commercially-used sweeteners, some of which are artificial, others natural, and measured how well the bacteria multiplied.
Around three‑quarters of the sweeteners changed how at least one bacterial species grew. Some sweeteners slowed down or stopped the growth of certain bacteria linked to a healthy gut.
The researchers then tested each sweetener in combination with common compounds such as caffeine, vanillin (vanilla extract), advantame (an artificial sweetener) and eight commonly-used drugs to assess whether this had any impact on the gut bacteria. They found over 100 interactions where sweeteners acted differently when combined with other substances. In 34 cases, combinations made the effects stronger, while in 68 cases the effects were weaker.
Most striking was the combination of isosteviol (a compound derived from stevia, a sweetener widely used in the food and beverage industry) and the antidepressant duloxetine. This combination strongly suppressed Roseburia intestinalis and Parabacteroides merdae, two gut bacteria that play important roles in maintaining a healthy digestive system. In the US in 2023, over 4.2 million patients were prescribed duloxetine.
As no gut bacterium exists alone, but rather as part of a ‘community’ within the gut, the researchers created a synthetic community containing all 25 bacteria. After allowing it to grow over time, they tested the community against a variety of sweetener and drug combinations, looking at which species increased or decreased and whether the overall diversity changed.
By mimicking in this simplified way what might happen in the human gut, they showed that the combination of isosteviol and duloxetine reduced microbial diversity. A diverse microbiome is considered important for good gut health. The sweetener-drug combination also altered which bacterial species thrived or declined.
Further analysis showed that the effect of the isosteviol-duloxetine combination on the community increased toxicity towards certain host cells and interfered with other cells that play a role in the body’s inflammation and immune responses.
Dr Blasche said: “Sweeteners are often marketed as metabolically neutral, but our study challenges this idea. We found that they can directly affect gut bacteria, particularly when mixed with other compounds such as medication and food additives. These common combinations could have unintended effects on our gut microbiome.”
The researchers stress that, as their experiments were carried out in the lab, not tested in humans, more research needs to be done before it is possible to conclude that there will be direct health effects in people.
Professor Patil, the study’s senior author, added: “Our study suggests that artificial sweeteners don’t just pass through the body passively — they can interact with gut microbes, and these effects can be amplified or altered by other substances like medications. These findings can help guide new studies towards understanding how sweeteners might influence health in unexpected ways.”
The research was funded by the European Union’s Horizon 2020 programme and the UK Medical Research Council.
People who don’t eat meat may be less likely than meat eaters to reach the age of 100, according to a recent study. But before you reconsider your plant-based diet, there’s more to these findings than meets the eye.
The research tracked over 5,000 Chinese adults aged 80 and older who participated in the Chinese Longitudinal Healthy Longevity Survey, a nationally representative study that began in 1998. By 2018, those following diets that don’t contain meat were less likely to become centenarians compared with meat eaters.
On the surface, this appears to contradict decades of research showing that plant-based diets are good for your health. Vegetarian diets, for example, have been consistently linked to lower risks of heart disease and stroke, type 2 diabetes and obesity. These benefits come partly from higher fibre intake and lower saturated fat consumption.
So what’s going on? Before drawing any firm conclusions, there are several important factors to consider.
Your body’s needs change as you age
This study focused on adults aged 80 and older, whose nutritional needs differ markedly from those of younger people. As we age, physiological changes alter both how much we eat and what nutrients we need. Energy expenditure drops, while muscle mass, bone density and appetite often decline. These shifts increase the risk of malnutrition and frailty.
Most evidence for the health benefits of diets that exclude meat comes from studies of younger adults rather than frail older populations. Some research suggests older non-meat eaters face a higher risk of fractures due to lower calcium and protein intake.
In later life, nutritional priorities shift. Rather than focusing on preventing long-term diseases, the goal becomes maintaining muscle mass, preventing weight loss and ensuring every mouthful delivers plenty of nutrients.
The study’s findings may, therefore, reflect the nutritional challenges of advanced age, rather than any inherent problems with plant-based diets. Crucially, this doesn’t diminish the well-established health benefits of these diets for younger and healthier adults.
Maintaining muscle mass in older age is important, and that requires protein. Photo by Barbara Olsen on Pexels
Here’s a crucial detail: the lower likelihood of reaching 100 among non-meat eaters was only observed in underweight participants. No such association was found in older adults of healthy weight.
Being underweight in older age is already strongly linked with increased risks of frailty and death. Body weight therefore appears to be a key factor in explaining these findings.
It’s also worth remembering that this was an observational study, meaning it shows associations rather than cause and effect. Just because two things occur together doesn’t mean one causes the other.
The findings also align with the so-called “obesity paradox” in ageing, where a slightly higher body weight is often linked to better survival in later life.
Notably, the reduced likelihood of reaching 100 observed among non-meat eaters was not evident in those who included fish, dairy or eggs in their diets. These foods provide nutrients that are essential for maintaining muscle and bone health, including high-quality protein, vitamin B12, calcium and vitamin D.
Older adults following these diets were just as likely to live to 100 as meat eaters. The researchers suggested that including modest amounts of animal-source foods may help prevent undernutrition and loss of lean muscle mass in very old age, compared with strictly plant-based diets.
What this means for healthy ageing
Rather than focusing on whether one diet is universally better than another, the key message is that nutrition should be tailored to your stage of life. Energy needs decline with age (due to decreased resting energy expenditure), but some nutrient requirements increase.
Older adults still require adequate protein, vitamin B12, calcium and vitamin D – especially to preserve muscle mass and prevent frailty. In older adulthood, preventing malnutrition and weight loss often becomes more important than long-term chronic disease prevention.
Plant-based diets can still be healthy choices, but they may require careful planning and, in some cases, supplementation to ensure nutritional adequacy, particularly in later life.
The bottom line is that our nutritional needs at 90 may look very different from those at 50, and dietary advice should reflect these changes across the lifespan. What works for you now might need adjusting as you age – and that’s perfectly normal.
A team of scientists from the University of Granada (UGR), the Granada Institute for Biomedical Research (ibs.GRANADA), the Public University of Navarra, and the Biomedical Research Networking Center (CIBER) has demonstrated that limiting food intake to an eight-hour window helps maintain weight loss 12 months after the end of the intervention in overweight or obese adults.
The research has revealed that intermittent fasting – specifically the method popularly known as 16:8, in which participants fast for 16 hours and are allowed to eat during the remaining eight hours – is an effective strategy for maintaining weight loss in the medium term. The study shows that these benefits persist one year later, regardless of whether the eight-hour eating window occurs early in the day (between 9 a.m. and 5 p.m., known as early fasting) or later (between 1 p.m. and 9 p.m., known as late fasting), compared to people who maintain their usual eating routine for 12 hours or more.
The results show that both the early-fasting and late-fasting groups managed to maintain significantly greater weight loss after 12 months. Furthermore, the early-fasting group maintained a greater reduction in fat mass. According to the researchers, these findings suggest that this type of nutritional intervention is not only feasible and effective in the short term but now also demonstrates sustainable effects over time.
Body Composition Assessment One Year Later
The study, recently published in Clinical Nutrition, involved 99 adults – half of whom were women – who were overweight or obese. During the first 12 weeks, participants were divided into four groups, all of which followed a Mediterranean diet education program: a control group that maintained its usual eating window (12 hours or longer), an early fasting group (an 8-hour window beginning before 10:00 a.m.), a late fasting group (an 8-hour window beginning after 1:00 p.m.), and a self-selected group where participants chose their own 8-hour eating window.
Changes in weight, fat mass, and fat-free mass were measured before and after the 12-week intervention, as well as one year after the study ended. This study is part of a larger project whose main results have been published in the prestigious journal *Nature Medicine*, where it was observed that participants who practiced TRE, regardless of their eating schedule, lost an average of 3–4 kilos more than the group that received only nutritional recommendations.
Dr. Alba Camacho Cardeñosa, a researcher at the University Joint Institute for Sport and Health (iMUDS) at the University of Granada (UGR) and a postdoctoral fellow at ibs.GRANADA in the Endocrinology and Nutrition Department at San Cecilio University Clinical Hospital, is the study’s first author. She explains that “to date, although we knew that intermittent fasting promotes modest weight loss in the short term, it was unclear whether its effects were sustained over time. By evaluating the participants 12 months after the intervention ended, we demonstrated that the changes in body weight persist.” In addition, the researchers highlight that “a very positive finding is that one in three people decided to continue practicing intermittent fasting on their own during that year of follow-up, suggesting that it is a relatively easy habit to integrate into daily life.”
A Flexible Strategy Against Obesity
The researchers emphasise that an intervention involving just 12 weeks of intermittent fasting may represent an effective medium-term strategy for weight control in overweight or obese adults. Since both early- and late-day fasting regimens have been shown to be effective, the findings offer valuable flexibility for patients to choose the schedule that best suits their lifestyle, thereby improving adherence and success in obesity treatment.
Dr Kadima Tshiyoyo, Marni Oberholzer and Ryan Bosch
A team of young researchers at the University of Pretoria (UP) is developing an innovative health supplement that transforms citrus peel waste into a potentially powerful tool against lifestyle diseases such as diabetes, obesity and high cholesterol, while also improving the affordability and accessibility of preventative health products for low-income communities.
The NutraPectin project is led by postdoctoral research fellow Dr Kadima Tshiyoyo, alongside recent Master of Science in Biochemistry graduates Ryan Bosch and Marni Oberholzer. Together, the team from UP’s Faculty of Natural and Agricultural Sciences (NAS) is converting citrus processing waste into a pectin-rich nutraceutical using green extraction technology. When consumed with food, pectin can help slow sugar absorption, reduce cholesterol levels and support gut health.
“South Africa’s growing burden of lifestyle diseases and abundance of agricultural waste inspired our work,” Dr Tshiyoyo said. “NutraPectin uses sustainable green methods to extract bioactive compounds from waste, which are valuable and essential in the management of lifestyle diseases such as diabetes and obesity.”
Turning science into solutions
The development of NutraPectin addresses two growing challenges: the rising prevalence of lifestyle-related diseases and the environmental cost of agricultural and food processing waste. Citrus peel, which is typically discarded in large volumes by the citrus industry, is rich in pectin and other bioactive compounds that can be recovered and repurposed.
Bosch says the NutraPectin research was his honours-degree project under Prof Samkelo Malgas of UP’s Department of Biochemistry, Genetics and Microbiology. “I was drawn to the project as I am passionate about maintaining the environment, and I was excited to investigate how food waste could be converted into useful healing products.”
For Bosch and Oberholzer, the project represents more than laboratory research. It is an opportunity to demonstrate how student-led science can be translated into solutions with tangible social and economic impact, particularly in a country where both healthcare access and food system sustainability remain pressing concerns.
“Sustainability should both underlie and overarch most research if we want to see true economic and social growth,” Oberholzer said. “South Africa has so much potential to sustainably improve and empower our agricultural industry by targeting circularity through waste valorisation. UP was foundational in this development, most markedly through our excellent supervisor’s guidance. We were allowed to explore beyond the strict boundaries of our degrees.”
The project is rooted in the Biocatalysis and Processing Research Group in the Department of Biochemistry, Genetics and Microbiology within the NAS Faculty, under the supervision of Prof Malgas. He says the work highlights the importance of university-based research in advancing both innovation and entrepreneurship, while also addressing societal challenges through science-driven solutions.
“This pectin extraction from citrus waste represents a remarkable advancement in enzyme biotechnology. The student-led innovation model effectively merges hands-on research with mentorship, equipping students with essential skills in biotechnological methods,” Prof Malgas said. “It demonstrates that active student involvement is crucial in driving innovation and developing talent. The technology promises significant environmental benefits by promoting sustainable waste use and reinforcing the circular economy. Additionally, it has the potential to drive economic growth for South Africa’s citrus industry through the production of high-value pectin.”
Catalyst competition winner
A major milestone for the project came in 2024 when NutraPectin was named the winner of the Catalyst competition, an early-stage biotech start-up pitch event organised by Immobazyme in partnership with UVU Bio. The competition brought together seven finalist teams developing biotech solutions aimed at real-world challenges.
NutraPectin stood out to judges for its dual impact: addressing lifestyle diseases while simultaneously offering a scalable approach to waste valorisation in the agricultural sector. The win signalled growing confidence in the commercial viability of the technology, moving it beyond academic research into the early stages of commercialisation.
Indeed, the Catalyst win also unlocked a structured support package designed to accelerate start-up development. This includes access to laboratory space, a reagent and consumables credit facility, mentorship from industry executives, business development training, and specialised technical support to help refine and scale production processes.
The team has also secured a Technology Innovation Agency Seed Grant, which will further support the optimisation of production methods and the transition from prototype to scalable manufacturing.
However, NutraPectin remains in the early stages of development. The current focus is on developing a production pathway that can support larger-scale manufacturing, enabling the product to be brought to market.
Looking ahead, the team envisions NutraPectin as a locally produced, widely accessible nutraceutical that supports preventative health while creating value from South Africa’s agricultural resources.
To move from a laboratory success to a market-ready product, the team is now seeking additional funding and industry partnerships to support pilot-scale production and regulatory development.
“It is envisioned that NutraPectin can move from optimisation and scale-up to a market-ready prototype supported by partnerships and collaboration to expand within South Africa,” Dr Tshiyoyo said. “Our long-term goal is to make the product affordable and accessible while creating sustainable health and commercial impact. We see NutraPectin growing into a versatile innovation with potential in the supplement, health additive, cosmetic, and pharmaceutical industries.”
As South Africa’s Youth Month draws to a close, the NutraPectin team’s work reflects the growing role of young researchers in developing solutions that integrate health, sustainability and innovation. Dr Tshiyoyo advises other young researchers to stay focused and work steadily towards their goals. “My message to the youth is think long term but act today; many consistent steps over the years can lead to your breakthrough,” he said.
New clinical trial results show supplements with omega-3s have no effect on memory or cognitive function in older adults at risk for Alzheimer’s disease
Fish oil supplements are purported to have cognitive benefits from the omega-3 fatty acids they contain, essential nutrients that help form neuron connections. But a new Keck Medicine of USCstudy published in eBioMedicine suggests that increasing omega-3 levels via supplements has little effect on brain health despite showing evidence that the nutrients directly reach the brain.
The two-year, placebo-controlled, double-blinded study of older adults with an elevated risk of developing Alzheimer’s showed that high doses of omega-3s did not improve memory, cognitive function or brain cell loss in areas of the brain related to Alzheimer’s.
“We all wish there was a silver bullet for preventing Alzheimer’s, but our findings showed that fish oil supplements do not appear to protect brain health,” said Hussein Naji Yassine, MD, director of the USC Center for Personalized Brain Health and lead investigator of the study. “While omega-3s play an important role in forming brain cell connections needed for cognition, our results do not support fish oil supplements as a preventive measure against Alzheimer’s.”
How the study was conducted
Researchers recruited 365 adults, ages 55 to 80 who rarely ate fish, which is rich in omega-3s, and who study authors considered at risk for Alzheimer’s. About half (47%) carried an APOE4 gene, the strongest genetic risk factor for late-onset Alzheimer’s. Participants were randomly chosen to receive either daily fish oil supplements or a placebo. The supplements contained 2000mg of docosahexaenoic acid (DHA), a key omega-3 involved in brain function.
Researchers were first interested to learn whether the omega-3 in the supplement was able to reach the brain.
They measured DHA levels in cerebrospinal fluid, which surrounds the brain, and found an average 17% increase of DHA levels in patients’ brains after six months, confirming the omega-3 reached its intended target.
Next, researchers tested participants’ memory and cognitive abilities at the beginning of the study and again two years later. Study participants who took DHA supplements did no better on the tests than those who took a placebo. Brain scans also showed that supplements did not prevent shrinkage of the hippocampus, a brain region important for memory that is often used as a marker of brain aging and Alzheimer’s risk.
Looking beyond supplements
Now, Yassine and his team are focused on solving why omega-3 supplements can reach the brain but not affect brain health. Based on their previous research, they believe omega-3s may work better as a part of a Mediterranean-style diet, which is naturally rich in omega-3s and linked with lower Alzheimer’s risk, than in a standalone supplement.
“We’re focused on better understanding how the brain processes omega-3s and whether factors, such as poor health, dietary pattern, genetic risk and age, may change the brain’s ability to effectively absorb and use omega-3s,” said Yassine. “We are working to develop medications that may help the brain better utilise these nutrients to preserve cognitive function.”
Holistic lifestyle remains the best prevention
While out of scope of the study, the researchers stress that overall healthy living – rather than relying on fish oil supplements alone – is the best way to protect brain health.
“Staying healthy throughout life remains the most powerful tool we have for reducing Alzheimer’s risk, including regular exercise, quality sleep and a balanced diet,” said Yassine. “Living a healthy lifestyle is the brain’s equivalent of getting regular car maintenance and high-quality oil changes. The brain is more likely to lose greater function if health issues in other parts of the body go unaddressed, in the same way that car engines stop working if regular maintenance is skipped.”
Eliminating sugar from your diet may be more detrimental than previously thought, according to an animal study being presented Saturday at ENDO 2026, the Endocrine Society’s annual meeting in Chicago, Ill.
“Completely removing sucrose from a low-fat diet may unexpectedly disrupt gut health and promote inflammation and metabolic dysfunction, highlighting that balanced nutrition is more important than simply eliminating sugar,” said Rasheed Ahmad, PhD, principal scientist and head of the Immunology & Microbiology Department at the Dasman Diabetes Institute, in Kuwait City, Kuwait. The institute was founded by Kuwait Foundation for the Advancement of Sciences. Researchers investigated the effects of a sucrose-free low-fat diet compared to a sucrose-containing low-fat control diet in two groups of mice for 16 weeks.
They evaluated glucose tolerance, insulin sensitivity, circulating metabolic hormones, the gut microbiome and inflammation in the colon and liver.
Mice fed the sucrose-free diet developed impaired glucose control, insulin resistance, gut microbial imbalance, intestinal inflammation and fatty liver changes, despite having no significant differences in body weight compared with control mice.
“The findings suggest that complete removal of sucrose from a low-fat diet may negatively affect gut microbiota and metabolic health,” Ahmad said. “The study highlights the importance of maintaining balanced dietary carbohydrates to support gut and immune homeostasis.”
Until now, the consequences of restrictive diets that eliminate sugar from a low-fat diet were unknown.
“This research may influence future dietary recommendations by emphasizing the importance of maintaining a healthy gut microbiome rather than focusing only on sugar restriction,” Ahmad said. “In the long term, these findings could help improve strategies for preventing and managing metabolic disorders, fatty liver disease and chronic inflammatory conditions.”
“Studies such as this reflect our institute’s commitment to advancing evidence-based scientific discoveries that improve public health outcomes and deepen our understanding of metabolic disease,” said Faisal Hamed Al-Refaei, MD, Acting Director General of Dasman Diabetes Institute.
A new study from the University of Kansas details how US tobacco corporations expanded into global food markets from the mid-1980s to the mid-2000s, using strategies honed through cigarette sales to market ultra-processed foods, which are industrially processed and contain ingredients and additives that maximise their appeal. The research appears in the American Journal of Public Health.
“We’d previously published on US tobacco company activities in relation to the US food system,” said lead author Tera Fazzino, associate professor of psychology at the University of Kansas. “In that prior study, I noted that tobacco-owned food company activities extended far beyond the United States. They had an extensive international business development strategy. Given the global conversation about ultra-processed and hyperpalatable foods saturating food systems, it felt important to investigate that international dimension. This study contributes to understanding the origin and nature of these foods and how they became widespread globally.”
For two decades, tobacco firms heavily invested in food companies, applying marketing, distribution and product-engineering strategies developed in the tobacco business.
“The scale was massive,” said Fazzino, who also serves as associate scientist at the KU Life Span Institute’s Cofrin Logan Center for Addiction Research and Treatment. “For Philip Morris, its food business, for a substantial period of time, generated sales comparable to its tobacco business – roughly a 50–50 split. A significant portion of those food revenues came from international markets.”
Meanwhile, Fazzino said, R.J. Reynolds had closer to 30% of its portfolio in food sales.
“But it also maintained a very large international food presence,” she said. “In many of the regions where these companies operated, their food subsidiaries were among the largest players in those markets at the time.”
Fazzino’s co-authors were KU graduate students Sydney Kong and Gayeon Lee, along with undergraduate research assistant Madison Stewart.
The researchers found that tobacco companies applied their long-established business strategies directly to their food operations.
“On the business development side, they aggressively expanded and acquired local companies to build infrastructure within regions,” Fazzino said. “This allowed them to distribute their primary products efficiently. They also created coordinated product distribution and sales systems that integrated both tobacco and food operations.”
On the product-development side, tobacco companies used strategies similar to those previously applied to cigarettes.
“For example, they manipulated product size,” Fazzino said. “Just as they had introduced ‘king-size’ cigarettes to increase consumption occasions, they later used similar size strategies in food products – king-size sugary drinks, cookies and other items.”
Fazzino said tobacco firms also developed products that maintained “full flavour” while being marketed as lighter or healthier.
“In tobacco, this meant ‘low-tar’ or ‘low-nicotine’ cigarettes,” she said. “In food, it meant ‘low-fat’ or ‘light’ versions of products designed to appeal to health-conscious consumers while retaining strong flavour profiles.”
The researchers found that different tobacco firms developed their food businesses in different geographic areas, even if their marketing and product-formulation strategies were similar. According to Fazzino, the data indicate tobacco companies held leading market shares in multiple regions.
“Philip Morris expanded rapidly into Canada, where it held leading market positions in many product categories as early as the late 1980s,” she said. “Its entry into the Canadian market was swift and aggressive. The company also expanded significantly into Europe and secondarily into parts of Asia and the Asia-Pacific region. R.J. Reynolds primarily focused on Central and South America, and Mexico, and also expanded into parts of Europe and Asia. Collectively, this meant that from the late 1980s through the mid-2000s, large portions of the globe were covered by one or both companies.”
The public health implications of increased ultra-processed and hyperpalatable foods in the world’s food supply are substantial, Fazzino said.
“Globally, there is ongoing discussion among scientists, policymakers and citizens about the shift toward ultra-processed and hyperpalatable foods,” she said. “There is now strong evidence that these foods carry significant health risks. Their risk profile parallels other major contributors to morbidity and mortality, including smoking. As these products were disseminated internationally using highly refined and efficient business strategies, the potential for global health harm was significant.”
Fazzino cited rising rates of obesity and related metabolic and cardiometabolic diseases in many parts of the world.
“These increases have paralleled shifts in food systems toward more ultra-processed and hyperpalatable foods,” she said.
Although tobacco companies divested from food businesses in the early to mid-2000s, Fazzino said their influence in disseminating ultra-processed foods globally leaves a lasting legacy.
“The food companies continued operating under profit-maximizing models that had already proven successful for other addictive products,” she said. “It’s likely other food companies observed these strategies and adopted similar approaches. As a result, these practices appear to have spread across the global food industry.”
According to Fazzino, today at least 70% of the US food supply is composed of hyperpalatable foods, and their presence globally is elevated. The KU researcher said policymakers could apply lessons from tobacco regulation, including labelling, marketing restrictions and litigation.
“However, food presents unique challenges because people must eat,” Fazzino said. “In food systems saturated with ultra-processed and hyperpalatable products, such as in the US, stronger regulation of the nutrient profiles and properties that drive addictive qualities may be necessary. In contrast, South American countries, which have not experienced saturation of their food supplies, have implemented warning labels and other measures with demonstrated public health benefits.”
