Grapefruit and pummelo contain compounds called furanocoumarins that may affect the blood levels of more than 100 prescription drugs, so that people taking these medications are advised to remove these fruits from their diets. Research published in New Phytologistreveals genetic information about the synthesis of furanocoumarins in different citrus plant tissues and species and provides new insights that could be used to develop grapefruit and pummelo that lack furanocoumarins.
The research indicates that the production of furanocoumarins in citrus fruit is dependent on the integrity of a single gene within a multi-gene cluster that encodes enzymes of the 2-oxoglutarate-dependent dioxygenase family.
“This research helps us to understand why fruit of certain citrus species produce furanocoumarins and demonstrates how breeders and researchers could develop furanocoumarin-free citrus varieties,” said co–corresponding author Yoram Eyal, PhD, of the Volcani Center, in Israel.
Amid a global surge in measles cases, new research suggests that undernutrition may be exacerbating outbreaks in areas suffering from food insecurity. A study involving over 600 fully vaccinated children in South Africa found those who were undernourished had substantially lower levels of antibodies against measles.
Researchers from McGill University, UC Berkeley School of Public Health and the University of Pretoria tracked the children’s growth over time as an indicator of undernutrition and measured their antibody levels through blood tests. Children who were stunted around age three had an average of 24-per-cent-lower measles antibody levels by age five compared to their typical-sized peers.
The findings, published in Vaccine, suggest that undernutrition may affect the duration of vaccine protection.
This indicates that addressing child hunger could be a key piece of the puzzle in preventing viral outbreaks, said senior author Jonathan Chevrier, an Associate Professor at McGill.
A growing threat worldwide
Measles is a highly contagious viral infection that causes symptoms such as a rash, fever and cough, and can lead to severe complications, especially in young children. The disease is a threat in regions where it was once under control, including Canada, which in 2024 reported its highest number of cases in nearly a decade.
“Global measles cases declined from 2000 to 2016, but the trend reversed in 2018, driven in part by under-vaccination and the impact of the pandemic. Measles is now making a strong comeback in many parts of the world despite being preventable with vaccination and adequate immunity,” said co-author Brian Ward, Professor at McGill’s.
“We need to vaccinate children against infectious diseases that are preventable and ensure they are protected,” said first author Brenda Eskenazi, Professor at the University of California, Berkeley. “This is especially important now, given that many known diseases are expected to spread with climate change.”
About 22% of children under age five worldwide – approximately 148 million – were stunted in 2022, Chevrier added, with the highest rates in Asia and sub-Saharan Africa.
The team plans to monitor the children in the study as they grow older to understand whether the effects of early-life undernutrition persist.
A new study from researchers at Tufts University, which appears in Nature Medicine, estimates that 2.2 million new cases of type 2 diabetes and 1.2 million new cases of cardiovascular disease occur each year globally due to consumption of sugar-sweetened beverages.
In developing countries, the case count is particularly sobering. In Sub-Saharan Africa, the study found that sugar-sweetened beverages contributed to more than 21% of all new diabetes cases. In Latin America and the Caribbean, they contributed to nearly 24% of new diabetes cases and more than 11% of new cases of cardiovascular disease.
Colombia, Mexico, and South Africa are countries that have been particularly hard hit. More than 48% of all new diabetes cases in Colombia were attributable to consumption of sugary drinks. Nearly one third of all new diabetes cases in Mexico were linked to sugary drink consumption. In South Africa, 27.6% of new diabetes cases and 14.6% of cardiovascular disease cases were attributable to sugary drink consumption.
Sugary beverages are rapidly digested, causing a spike in blood sugar levels with little nutritional value. Regular consumption over time leads to weight gain, insulin resistance, and a host of metabolic issues tied to type 2 diabetes and heart disease, two of the world’s leading causes of death.
“Sugar-sweetened beverages are heavily marketed and sold in low- and middle-income nations. Not only are these communities consuming harmful products, but they are also often less well equipped to deal with the long-term health consequences,” says Dariush Mozaffarian, senior author on the paper and director of the Food is Medicine Institute at the Friedman School.
As countries develop and incomes rise, sugary drinks become more accessible and desirable, the authors say. Men are more likely than women to suffer the consequences of sugary drink consumption, as are younger adults compared to their older counterparts, the researchers say.
“We need urgent, evidence-based interventions to curb consumption of sugar-sweetened beverages globally, before even more lives are shortened by their effects on diabetes and heart disease,” says Laura Lara-Castor, NG24, first author on the paper who earned her PhD at the Friedman School and is now at the University of Washington.
The study’s authors call for a multi-pronged approach, including public health campaigns, regulation of sugary drink advertising, and taxes on sugar-sweetened beverages. Some countries have already taken steps in this direction. Mexico, which has one of the highest per capita rates of sugary drink consumption in the world, introduced a tax on the beverages in 2014. Early evidence suggests that the tax has been effective in reducing consumption, particularly among lower-income individuals.
“Much more needs to be done, especially in countries in Latin America and Africa where consumption is high and the health consequence severe,” says Mozaffarian. “As a species, we need to address sugar-sweetened beverage consumption.”
A University of Copenhagen study of plant-based drinks reveals a common issue: they are lacking in proteins and essential amino acids compared to cow’s milk. The explanation lies in their extensive processing, causing chemical reactions that degrade protein quality in the product and, in some cases, produce new substances of concern.
Over the last decade, the global market for plant-based beverages has seen remarkable growth, with oat, almond, soy and rice drinks emerging as popular alternatives to cow’s milk in coffee and oatmeal during this time.
One of the likely reasons for millions of litres of plant-based drinks ending up in the shopping baskets of consumers is that their climate footprint is often lower than that of cow’s milk. But consumers would be mistaken if they considered plant-based beverages healthier than cow’s milk. This is highlighted in a new study conducted by the University of Copenhagen in collaboration with the University of Brescia, Italy.
In the study, published in Food Research International, researchers examined how chemical reactions during processing affect the nutritional quality of ten different plant-based drinks, comparing them with cow’s milk. The overall picture is clear:
“We definitely need to consume more plant-based foods. But if you’re looking for proper nutrition and believe that plant-based drinks can replace cow’s milk, you’d be mistaken,” says Department of Food Science professor Marianne Nissen Lund, the study’s lead author.
Long shelf life at the expense of nutrition
While milk is essentially a finished product when it comes out of a cow, oats, rice, and almonds require extensive processing during their conversion to a drinkable beverage. Moreover, each of the plant-based drinks tested underwent Ultra High Temperature (UHT) treatment, a process that is widely used for long-life milks around the world. In Denmark, milk is typically found only in the refrigerated sections of supermarkets and is low-pasteurized, meaning that it receives a much gentler heat treatment.
“Despite increased plant-based drink sales, cow milk sales remain higher. Consequently, plant-based drinks undergo more intense heat treatments than the milk typically sold in Denmark, in order to extend their shelf life. But such treatment comes at a cost,” says Marianne Nissen Lund.
UHT treatment triggers a so-called “Maillard reaction”, a chemical reaction between protein and sugar that occurs when food is fried or roasted at high temperatures. Among other things, this reaction impacts the nutritional quality of the proteins in a given product.
“Most plant-based drinks already have significantly less protein than cow’s milk. And the protein, which is present in low content, is then additionally modified when heat treated. This leads to the loss of some essential amino acids, which are incredibly important for us. While the nutritional contents of plant-based drinks vary greatly, most of them have relatively low nutritional quality,” explains the professor.
For comparison, the UHT-treated cow’s milk used in the study contains 3.4 grams of protein per liter, whereas 8 of the 10 plant-based drinks analyzed contained between 0.4 and 1.1 grams of protein. The levels of essential amino acids were lower in all plant-based drinks. Furthermore, 7 out of 10 plant-based drinks contained more sugar than cow’s milk.
Heat treatment may produce carcinogens
Besides reducing nutritional value, heat treatment also generates new compounds in plant-based drinks. One such compound measured by the researchers in four of the plant-based drinks made from almonds and oats is acrylamide, a carcinogen that is also found in bread, cookies, coffee beans and fried potatoes, including French fries.
“We were surprised to find acrylamide because it isn’t typically found in liquid food. One likely source is the roasted almonds used in one of the products. The compound was measured at levels so low that it poses no danger. But, if you consume small amounts of this substance from various sources, it could add up to a level that does pose a health risk,” says Marianne Nissen Lund.
Additionally, the researchers detected α-dicarbonyl compounds and hydroxymethylfurfural (HMF) in several of the plant-based drinks. Both are reactive substances that could potentially be harmful to human health when present in high concentrations, although this is not the case here.
While professor of nutrition Lars Ove Dragsted is not particularly concerned about the findings either, he believes that the study highlights how little we know about the compounds formed during food processing:
“The chemical compounds that result from Maillard reactions are generally undesirable because they can increase inflammation in the body. Some of these compounds are also linked to a higher risk of diabetes and cardiovascular diseases. Although our gut bacteria break down some of them, there are many that we either do not know of or have yet to study,” says Lars Ove Dragsted of the Department of Nutrition, Execercise and Sports.
Professor Dragsted adds: “This study emphasizes why more attention should be paid to the consequences of Maillard reactions when developing plant-based foods and processed foods in general. The compounds identified in this study represent only a small fraction of those we know can arise from Maillard reactions.”
Make Your Own Food
According to Professor Marianne Nissen Lund, the study highlights broader issues with ultra-processed foods:
“Ideally, a green transition in the food sector shouldn’t be characterized by taking plant ingredients, ultra-process them, and then assuming a healthy outcome. Even though these products are neither dangerous nor explicitly unhealthy, they are often not particularly nutritious for us either.”
Her advice to consumers is to: “generally opt for the least processed foods and beverages, and to try to prepare as much of your own food as possible. If you eat healthy to begin with, you can definitely include plant-based drinks in your diet – just make sure that you’re getting your nutrients from other foods.”
At the same time, Professor Lund hopes that the industry will do more to address these issues: “This is a call to manufacturers to further develop their products and reconsider the extent of processing. Perhaps they could rethink whether UHT treatment is necessary or whether shorter shelf lives for their products would be acceptable.”
Using significantly higher doses of vitamin D than recommended for five years did not affect the incidence of type 2 diabetes in elderly men and women, according to a new study from the University of Eastern Finland which appears in Diabetologia.
In population studies, low levels of vitamin D in the body have been associated with a higher risk of type 2 diabetes, but such observational studies cannot directly prove a causative link. Experimental studies have shown that the use of significantly higher doses of vitamin D than recommended slightly reduces the risk of developing type 2 diabetes in individuals with impaired glucose metabolism, ie, those with prediabetes. In contrast, no effects have been observed in individuals without prediabetes. However, the studies with non-prediabetic subjects have used relatively small doses of vitamin D or have been short-term. Until now, there has been no research data on the effects of long-term use of high doses of vitamin D on the risk of type 2 diabetes in individuals without glucose metabolism disorders.
In the Finnish Vitamin D Trial (FIND) conducted at the University of Eastern Finland from 2012 to 2018, 2 495 men aged 60 and older and women aged 65 and older were randomised for five years into either a placebo group or groups receiving either 40 or 80 micrograms of vitamin D3 per day. In the statistical analyses of the now-published sub-study, 224 participants who were already using diabetes medications at the start of the study were excluded. Comprehensive information was collected from the participants on lifestyle, nutrition, diseases, and their risk factors. Data was also obtained from national health registers. About one-fifth were randomly selected for more detailed examinations, and blood samples were taken from them.
During the five years, 105 participants developed type 2 diabetes: 38 in the placebo group, 31 in the group receiving 40 micrograms of vitamin D3 per day, and 36 in the group receiving 80 micrograms of vitamin D3 per day. There was no statistically significant difference in the number of cases between the groups.
In the more closely studied group of 505 participants, the blood calcidiol level, which describes the body’s vitamin D status, was on average 75nmol/L at the start, and only 9% had a low level, ie, below 50nmol/L. After one year, the calcidiol level was on average 100nmol/L in the group that used 40 micrograms of vitamin D per day and 120nmol/L in the group that used 80 micrograms of vitamin D per day. There was no significant change in the placebo group. The effects of vitamin D on blood glucose and insulin levels, body mass index, and waist circumference were examined during the first two years of the study, but no differences were observed between the groups.
The findings of the FIND study reinforce the view that the use of higher doses of vitamin D than recommended does not significantly affect the risk of developing type 2 diabetes in individuals without prediabetes and who already have a good vitamin D status. So far, there is no research data on whether high doses of vitamin D can be beneficial in preventing type 2 diabetes in individuals without prediabetes but with vitamin D deficiency.
Public health recommendations generally suggest drinking eight cups of water a day. And many people just assume it’s healthy to drink plenty of water.
Now researchers at UC San Francisco have taken a systematic look at the available evidence, analysed 18 randomised controlled trials. In their review, published in JAMA Network Open, they concluded that drinking enough water can help with weight loss and prevent kidney stones, as well as migraines, urinary tract infections and low blood pressure.
“For such a ubiquitous and simple intervention, the evidence hasn’t been clear, and the benefits were not well established, so we wanted to take a closer look,” said Benjamin Breyer, MD, MAS, professor and chair of the UCSF Department of Urology.
“The amount of rigorous research turned out to be limited, but in some specific areas, there was a statistically significant benefit,” said Breyer, the senior author of the study. “To our knowledge, this is the first study assessing the benefits of water consumption on clinical outcomes broadly.”
Strong evidence suggested that drinking eight cups of water a day significantly decreased the likelihood of getting another kidney stone. Several studies found that drinking about six cups of water a day helped adults lose weight. But a study that included adolescents found that drinking a little more than eight cups of water a day had no effect.
Still, the authors said that encouraging people todrink water before meals would be a simple and cheap intervention that could have huge benefits, given the increased prevalence of obesity.
Other studies indicated that water can help prevent migraines, control diabetes and low blood pressure, and prevent urinary tract infections. Adults with recurrent headaches felt better after three months of drinking more water. Drinking about four more cups of water a day helped diabetic patients whose blood glucose levels were elevated.
Drinking an additional six cups a day of water also helped women with recurrent urinary tract infections. It reduced the number of infections and increased the amount of time between them. Drinking more water also helped young adults with low blood pressure.
“We know that dehydration is detrimental, particularly in someone with a history of kidney stones or urinary infections,” Breyer said. “On the other hand, someone who suffers from frequent urination at times may benefit from drinking less. There isn’t a one size fits all approach for water consumption.”
It’s generally estimated that around 10% of pregnant people struggle to meet their nutritional needs – but the real number could be far higher, according to new research in The Journal of Nutrition.
Over 90% of pregnant individuals are potentially failing to get enough iron, vitamin D, or vitamin E from the food they eat, while over one-third could be short of calcium, vitamin C, and vitamin A. Troublingly, almost two-thirds of pregnant people were also found to be getting insufficient dietary folate – a critical nutrient that helps prevent birth defects in the baby’s brain and spine.
“It’s important to remember that many pregnant people take prenatal vitamin supplements, which might help prevent nutritional deficiencies,” says lead author Dr Samantha Kleinberg, professor at Stevens Institute of Technology. “Nonetheless, this is a startling finding that suggests we need to be looking much more closely at whether pregnant individuals are getting the nutrients they need.”
Where most previous studies of nutrition during pregnancy relied on a few days of food diaries, or on simply asking people what they remembered eating, the Stevens team asked pregnant people to take before-and-after photos of everything they ate over two 14-day periods. Experts then reviewed the photos to assess the amount of food actually eaten and determine the nutrients consumed during each meal.
That’s a far more accurate approach, because people are notoriously bad at estimating portion size or accurately reporting what they’ve eaten, Dr Kleinberg explains. A photo-based approach is also much less laborious for pregnant people, making it easy to collect data over a period of weeks instead of just a few days.
“Most surveys only track diet over a day or two – but if you feel off one day and don’t eat much, or have a big celebratory meal over the weekend, that can skew the data,” Dr Kleinberg says. “By looking at a longer time period, and using photos to track diet and nutrition, we’re able to get a much richer and more precise picture of what people actually ate.”
The study found significant dietary variations between individuals, but also among the same individuals from one day to the next, suggesting that shorter studies and population-based reports might be failing to spot important nutritional deficits. “Some people eat really well, and others don’t – so if you just take an average, it looks like everything’s fine,” Dr Kleinberg explains. “This study suggests that in reality, an alarming number of pregnant people may not be getting the nutrients they need from their food.”
Using food photos also recorded the exact timing of meals and snacks, and to explore the way that patterns of eating behaviour correlated with total energy and nutrient intake. When pregnant people ate later in the day, the data shows, they were likely to consume significantly more total calories – potentially an important finding as researchers explore connections between eating behaviours and health problems such as gestational diabetes.
The current research didn’t directly study health outcomes, so it’s too early to say whether insufficient nutrition or excessive energy consumption is adversely impacting pregnant individuals or their babies. “We’ll be digging into that in future studies, and looking at possible connections with eating patterns and changes in glucose tolerance,” Dr Kleinberg says.
An international study has found that genetic variations in human carbohydrate-active enzymes may affect how people with irritable bowel syndrome (IBS) respond to a carbohydrate-reduced diet.
The research, which is published in Clinical Gastroenterology & Hepatology, shows that IBS patients with genetic defects in carbohydrate digestion had a better response to certain dietary interventions. This could lead to tailored treatments for IBS, using genetic markers to predict which patients benefit from specific diets.
Irritable bowel syndrome (IBS) is a digestive disorder affecting up to 10% of the global population. It is characterised by abdominal pain, bloating, diarrhoea, or constipation. Despite its prevalence, treating IBS remains a challenge as symptoms and responses to dietary or pharmacological interventions vary significantly.
Patients often connect their symptoms to eating certain foods, especially carbohydrates, and dietary elimination or reduction has emerged as an effective treatment option, though not all patients experience the same benefits.
Nutrigenetics (the science investigating the combined action of our genes and nutrition on human health) has highlighted how changes in the DNA can affect the way we process food. A well-known example is lactose intolerance, where the loss of function in the lactase enzyme hinders the digestion of dairy products.
Now, this pioneering new study suggests that genetic variations in human carbohydrate-active enzymes (hCAZymes) may similarly affect how IBS patients respond to a carbohydrate-reduced (low-FODMAP) diet.
The team have now revealed that individuals with hypomorphic (defective) variants in hCAZyme genes are more likely to benefit from a carbohydrate-reduced diet.
The study, involving 250 IBS patients, compared two treatments: a diet low in fermentable carbohydrates (FODMAPs) and the antispasmodic medication otilonium bromide. Strikingly, of the 196 patients on the diet, those carrying defective hCAZyme genes showed marked improvement compared to non-carriers, and the effect was particularly pronounced in patients with diarrhoea-predominant IBS (IBS-D), who were six times more likely to respond to the diet. In contrast, this difference was not observed in patients receiving medication, underscoring the specificity of genetic predisposition in dietary treatment efficacy.
These findings suggest that genetic variations in hCAZyme enzymes, which play a key role in digesting carbohydrates, could become critical markers for designing personalised dietary treatments for IBS. The ability to predict which patients respond best to a carbohydrate-reduced diet has the potential to strongly impact IBS management, leading to better adherence and improved outcomes.
Study leader Dr D’Amato, Gastrointestinal Genetics Research group at CIC bioGUNE and the Department of Medicine and Surgery at LUM University in in Italy.
In the future, incorporating knowledge of hCAZyme genotype into clinical practice could enable clinicians to identify in advance which patients are most likely to benefit from specific dietary interventions. This would not only avoid unnecessary restrictive diets for those unlikely to benefit but also open the door to personalised medicine in IBS.
The foundation for healthy eating behaviour starts in infancy. Young children learn to regulate their appetite through a combination of biological, psychological, and sociological factors. In a new paper published in Social Science & Medicine, researchers at the University of Illinois Urbana-Champaign propose a model that explores these factors and their interactions, providing guidelines for better understanding childhood appetite self-regulation.
Appetite self-regulation is related to general self-regulation, but it specifically concerns an individual’s ability to regulate food intake, which affects healthy development and obesity risk. Children are born with a capacity to regulate appetite based on hunger and satiety signals, but with increased exposure to environmental factors, their eating is increasingly guided by psychological reasoning and motivations. Therefore, it is important to take a developmental perspective to trace changes in eating behaviours over time, Ju stated.
Ju and her colleagues provide a comprehensive framework based on the biopsychosocial pathways model, which outlines three interacting categories: Biological factors, including sensory experience, physiological hunger and satiety signals, brain-gut interaction, and the influence of the gut microbiome; psychological factors, including emotional self-regulation, cognitive control, stress regulation, and reward processing;and social factors, such as parental behaviour and feeding practices, culture, geographic location, and food insecurity.
The researchers combine this framework with temperamental theory to explore how the pathways are modified by individual temperament.
Children react differently to stimuli based on their psychological and emotional make up, Ju explained. For example, openness to novelty and positive anticipation can affect whether a child is willing to try new foods. If a parent pressures their child to eat, it could be counter-productive for a child with heightened sensitivity to negative affect, causing the child to consume less.
The model also takes children’s developmental stages into account. Infants have basic appetite regulation based on physiological cues. They gradually become more susceptible to external influences and by age 3-5, children begin to exhibit greater self-control and emotional regulation.
“By analysing the pathways outlined in our model, we can better understand the combined influences of multiple factors on children’s appetite self-regulation and their motivations to approach food,” Ju said. “For example, the presence of palatable food may not generate similar responses in everyone. Children could approach food as a reward, for pleasure-seeking, or to regulate emotions. The underlying motivations can be diverse, and they are influenced by external factors as well as temperamental characteristics.”
Socio-environmental influences include parent-child interactions around food, as well as non-food-related caregiver practices that can impact the child’s emotional regulation. The household food environment, cultural value of food intake, and food availability are also important factors, the researchers stated.
“If we understand the differential susceptibility to various factors, we can identify and modify the environmental influences that are particularly obesogenic based on children’s temperamental characteristics. Then we will be able to provide more refined approaches to support children’s healthy eating behaviour,” Ju explained.
New research from the University of Waterloo suggests that men and women should have different kinds of food for breakfast in order to help lose weight.
The study, which employed a mathematical model of men’s and women’s metabolisms, showed that men’s metabolisms respond better on average to a meal laden with high carbohydrates like oats and grains after fasting for several hours, while women are better served by a meal with a higher percentage of fat, such as omelettes and avocados. The findings are out now in Computers in Biology and Medicine.
“Lifestyle is a big factor in our overall health,” said Stéphanie Abo, an Applied Mathematics PhD candidate and the lead author of the study. “We live busy lives, so it’s important to understand how seemingly inconsequential decisions, such as what to have for breakfast, can affect our health and energy levels. Whether attempting to lose weight, maintain weight, or just keep up your energy, understanding your diet’s impact on your metabolism is important.”
The study builds on an existing gap in research on sex differences in how men and women process fat. “We often have less research data on women’s bodies than on men’s bodies,” said Anita Layton, a professor of Applied Mathematics and Canada 150 Research Chair in Mathematical Biology and Medicine.
“By building mathematical models based on the data we do have, we can test lots of hypotheses quickly and tweak experiments in ways that would be impractical with human subjects.”
“Since women have more body fat on average than men, you would think that they would burn less fat for energy, but they don’t,” said Layton. “The results of the model suggest that women store more fat immediately after a meal but also burn more fat during a fast.”
Going forward, the researchers hope to build more complex versions of their metabolism models and extend beyond the consideration of biological sex by incorporating an individual’s weight, age, or stage in the menstrual cycle.
