Tag: 6/12/21

Eating More Avocados Edges Out Unhealthy Foods

Photo by Dirk Ribbler on Unsplash

In a novel study, researchers conducted a randomised controlled trial comparing the potential health effects between families of Mexican descent that consumed a low allotment of avocados (three per week) and families that consumed a high allotment (14 per week).

They found that the high avocado allotment families self-reported lower caloric consumption, reducing their intake of other foods, including dairy, meats and refined grains and their associated negative nutrients, such as saturated fat and sodium.

The findings, published in Nutrients, may offer insights into how to better address the burgeoning public health issues of obesity and related diseases, particularly in high-risk communities, said the authors.

“Data regarding the effects of avocado intake on family nutritional status has been non-existent,” said senior author Matthew Allison, MD, professor at UC San Diego School of Medicine.

“Recent trials have focused on individuals, primarily adults, and limited to changes in cardiometabolic disease blood markers. Our trial’s results provide evidence that a nutrition education and high avocado allotment reduces total caloric energy in Mexican heritage families.”

The soft and buttery insides of the avocado are rich in vitamins C, E, K and B6, plus riboflavin, niacin, folate, pantothenic acid, magnesium, potassium, lutein, beta carotene and omega-3 fatty acids.

Half of a medium-sized fruit provides up to 20% of the recommended daily fibre, 10% potassium, 5% magnesium, 15% folate and 7.5 grams of monounsaturated fatty acids.

For the study, researchers enrolled 72 families (231 individuals) consisting of at least three members each over the age of five, residing in the same home, free of severe chronic disease, not on specific diets, and of Mexican heritage. The families were randomised into two groups for six months, during which time both groups also received bi-weekly nutrition education sessions.

Researchers wanted to assess if increased but moderated consumption of a single, nutrient-dense food might measurably improve overall health and decrease diet-related disparities.

While no change in BMI or waist circumference was seen between the two groups during the trial, researchers noted that consuming more avocados appeared to speed satiety. Fats and some dietary fibres, such as those found in avocados, can impact total energy intake by influencing gastrointestinal functions, such as introducing bulk that slows gastric emptying, regulating glucose and insulin reactions, prolonging nutrient absorption and modifying key peptide hormones that signal fullness.

Interestingly, the study found that families consuming more avocados correspondingly reduced their consumption of animal protein, specifically chicken, eggs and processed meats, the latter of which are typically higher in fat and sodium. Current nutrition guidelines recommend reduced consumption of both fat and sodium.

But surprisingly, high avocado consumers also recorded decreased intake of calcium, iron, sodium, vitamin D, potassium and magnesium, which researchers said might be associated with eating less.

“Our results show that the nutrition education and high avocado intake intervention group significantly reduced their family total energy intake, as well as carbohydrate, protein, fat (including saturated), calcium, magnesium, sodium, iron, potassium and vitamin D,” said first author Lorena Pacheco.

“In secondary energy-adjusted analyses, the nutrition education and high avocado allotment group significantly increased their intake of dietary fibre, monounsaturated fatty acids, potassium, vitamin E and folate.”

Source: EurekAlert!

Should Unvaccinated-by-choice COVID Patients Get Less Priority?

Credit: ATS

A new opinion piece provides an exhaustive examination of the ethics of using hospital resources on unvaccinated-by-choice COVID patients with pneumonia, versus patients with other serious but slower illnesses.

In his article published online in the Annals of the American Thoracic Society, William F. Parker, MD, PhD, looked at cases in which hospitals delayed time-sensitive and medically necessary procedures for vaccinated adults when they were overwhelmed with unvaccinated patients who had severe, life-threatening COVID pneumonia and suggested an ethical framework for triaging these patients.

“These vaccinated patients are directly harmed when hospitals use all their resources to care for the many unvaccinated patients with COVID,” he wrote.  “For example, delaying breast cancer surgery by just four weeks increases the relative risk of death from the disease by 8%.”

Dr Parker argues for a contingency care standard prioritising emergency life-support, regardless of vaccination status, in order to save the most lives.  “Simply rejecting the use of vaccination in prioritisation of medical resources without analysis ignores the very real tradeoffs at play during a pandemic.  The pain and suffering of the vaccinated from deferred medical care require a deeper defense of caring for the unvaccinated.”

Eliminating double standards
He stated: “Even though the vast majority of patients who develop life-threatening COVID pneumonia are unvaccinated, hospitals still have ethical obligations to expand capacity and focus operations on caring for them—even if it means making vaccinated patients wait for important but less urgent care like cancer and heart surgeries.”

“If tertiary care centers turn inward and stop taking transfers of COVID patients from overwhelmed community hospitals, this will result in de facto triage in favor of lower benefit care and cause systematic harm to both the vaccinated and unvaccinated in vulnerable communities,” he adds.  “Hospitals must justify their nonprofit status by accepting transfers and prioritizing life-saving care during a pandemic surge.”

He cited the example of a surge in Los Angeles, when the public health department had to issue an order forcing elite hospitals to stop doing financially lucrative elective procedures and accept patient transfers from community hospitals with ICUs overwhelmed by COVID.

Reciprocity and proportionality
The principle of reciprocity supports a possible tiebreaker role for vaccination status when two patients have equivalent survival benefit from a scarce health care resource. However, a universal exclusion of the unvaccinated from life support during a pandemic surge fails the test of proportionality for reciprocity, according to Dr Parker.

Reciprocity is rewarding one positive action with another. One example of this principle is giving vaccinated people access to sporting or entertainment events that are off limits to the unvaccinated (even if negative for COVID). Proportionality is the principle that ‘payback’ should be proportional to the magnitude of the act.  For example, living kidney donors get moved way up the waitlist- the equivalent of four years of waiting time on dialysis.  This satisfies the proportionality principle.

Dr Parker points out that while the increased relative risk of death of 8% from deferring breast cancer surgery is awful, the absolute increase in risk is only one per 100, and perhaps only one per 200 for a two-week deferral.
“After the surge is over, the hospital can catch up on deferred elective surgeries,” he wrote. “The harm from a coronary artery bypass or cancer surgery delayed two weeks is real, but tiny in comparison to certain death from denying life support for respiratory failure.”

He concluded that: “There is a defensible role for vaccination status in triage as a limited tiebreaker, not as a categorical exclusion, but only in the context of a well-defined and transparent triage algorithm.  Despite the enormous financial pressure to do otherwise, elite academic centres are obligated to prioritise life support for emergency conditions to save as many lives as possible during COVID surges.”    

Source: EurekAlert!

Just Ten Minutes of Running Boosts Cognitive Function

Photo by Ketut Subiyanto on Pexels

Researchers have found that a mere ten minutes of running at moderate intensity boosts blood flow to the bilateral prefrontal cortex, improving cognitive function and mood. These findings, published in Scientific Reports, may contribute to the development of a wider range of treatment recommendations to benefit mental health.

Physical activity has many benefits as noted by a great body of evidence, such as the ability to lift mood, but in previous studies, cycling was often the form of exercise studied. However, running has always played an important role in the well-being of humans. Human running’s unique form and efficiency, which includes the ability to sustain this form of exertion (ie, by jogging as opposed to sprinting), and human evolutionary success are closely linked.

Despite this fact, researchers had not yet looked closely at the effects of running on brain regions that control mood and executive functions. “Given the extent of executive control required in coordinating balance, movement, and propulsion during running, it is logical that there would be increased neuronal activation in the prefrontal cortex and that other functions in this region would benefit from this increase in brain resources,” explained senior author Professor Hideaki Soya at the University of Tsukuba, Japan.

To test their hypothesis, the research team used the well-established Stroop Colour–Word Test and measured haemodynamic changes associated with brain activity while participants were engaged in each task. For example, in one task, incongruent information is shown, eg the word ‘red’ is written in green, and the participant must name the colour rather than read out the word. To do so, the brain must process both sets of information and inhibit the extraneous information. The Stroop interference effect was quantified by the difference in response times for this task and those for a simpler version of the task – stating the names of colour swatches.

The results show that, after ten minutes of moderate-intensity running, there was a significant reduction in Stroop interference effect time. Furthermore, bilateral prefrontal activation had significantly increased during the Stroop task and participants also reported being in a better mood. “This was supported by findings of coincident activations in the prefrontal cortical regions involved in mood regulation,” noted first author Chorphaka Damrongthai.

Given that many characteristics of the human prefrontal cortex are uniquely human, this study not only sheds light on the present benefits of running but also on the possible role that these benefits may have played in the evolutionary past of humans.

Source: EurekAlert!

Air Pollution Linked to Hypertension

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Chronic exposure to air pollution in the form of particulate matter contributes to the risk of cardiovascular and respiratory diseases, and in particular has been linked to hypertension, according to a study published in Scientific Reports.

Air pollution, accounting for more than 4.2 million deaths annually, is a significant health risk. The study assessed the impact of particulate pollution on the long-term incidence of hypertension in Spain, supporting the need to improve air quality to the extent possible in order to reduce the risk of cardiometabolic diseases among the population.

To this end, researchers have carried out a study, di@bet.es, which recruited 1103 participants aged 18–83. None of the participants presented with hypertension at the start of the study (2008–2010), and they were monitored until 2016–17. Participants were assigned air pollution concentrations for particulate matter, obtained through modeling and air quality readings. During this period, 282 cases of incident hypertension were recorded.

The study was carried out in collaboration with the air pollution department of the Research Centre for Energy, Environment and Technology (CIEMAT).

As explained by endocrinologist Sergio Valdés, “Several previous studies have described the short- and long-term association of ambient air pollutants with hypertension and blood pressure levels, but few studies have addressed the association between long-term exposure to these particles and the incidence of hypertension in a prospective manner. Therefore, the di@bet.es study has offered us the opportunity to do so in the Spanish population.”

Participants underwent a medical examination and had blood samples taken. They also answered questionnaires to obtain demographic information and variables such as smoking, exercise and diet.

Gemma Rojo, last study author, stated that “our data is consistent with a large body of evidence suggesting that air pollution may contribute to the pathogenesis of hypertension. It also supports the idea that the particulate component of air pollution is the greatest threat to the cardiovascular system.”

In this regard, she noted, “Although previous associations between exposure to gaseous pollutants and hypertension have shown some discrepancies, most studies reporting long-term exposure to particulate matter and incident high blood pressure have reported positive associations consistent with our findings.”

As Sergio Valdés explained, “our results support the need to improve air quality to the extent possible in order to reduce the risk of high blood pressure among our population, as even moderate levels such as those we report here increase the risk significantly.”

Source: Consorcio Centro de Investigación Biomédica en Red MP

Vaccine Mandate Battle Looms as Omicron Cases Surge

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As President Cyril Ramaphosa warns that the long-expected fourth wave is upon the country, a legal battle against mandatory vaccination is brewing even as Omicron rates create an unprecedented surge, likely driven through re-infections.  

Omicron, detected by South African scientists only two weeks ago, is now dominating in most provinces. However, he stressed that the country had been prepared for a fourth wave, having long been predicted by modellers. He reiterated the call for more vaccinations and to observe social distancing as much as possible over the festive season.

Vaccine mandates are now on the cards, which are expected to be introduced in early 2022. Civil rights groups including Afriforum and Sakeliga have threatened legal action if the government moves ahead on its plans to introduce vaccine mandates.

Afriforum called vaccine mandates a violation of personal freedoms, and cited Ramaphosa’s statement February this year saying that nobody in the country would be forced to take a vaccination.

As of Monday evening, reported test positivity rate now stands at 26.4%, which is well above the 10% ‘level of concern’ which had been reached a week ago.. In the third wave, it took about a month to go from this level to 25%

At this stage, there is only anecdotal evidence around Omicron’s severity which suggests milder disease.

Prof Dame Sarah Gilbert, one of the creators of the Oxford/AstraZeneca vaccine, echoed the warning that vaccine effectiveness may be reduced against Omicron, noting its spike protein contained mutations known to increase the transmissibility of the virus. She cautioned that “there are additional changes that may mean antibodies induced by the vaccines, or by infection with other variants, may be less effective at preventing infection with Omicron.

“Until we know more, we should be cautious, and take steps to slow down the spread of this new variant.”

Preliminary results published in a preprint paper awaiting peer review suggest that the re-infection hazard ratio for Omicron is 2.39, with a possible range of  1.88–3.11 falling within the 95% confidence interval. By contrast, they found that the Beta and Delta variants proliferated primarily as a result of increased transmissibility, not immune escape.