Data Doesn’t Support Need for COVID-19 Vaccine Boosters: Experts

COVID-19 vaccine booster shots might not be needed for most people, according to a large international review.

The review — conducted by a team that included scientists from the World Health Organization and the U.S. Food and Drug Administration — concluded that current vaccines are effective enough against severe COVID-19, even from the Delta variant, and that booster shots are unnecessary.

The findings, published in The Lancet, are based on a review of all available published literature and results of clinical trials.

“The vaccines that are currently available are safe, effective, and save lives,” said study co-author Dr. Soumya Swaminathan, chief scientist at the WHO.

“Although the idea of further reducing the number of COVID-19 cases by enhancing immunity in vaccinated people is appealing, any decision to do so should be evidence-based and consider the benefits and risks for individuals and society,” she said in a journal news release. “These high-stakes decisions should be based on robust evidence and international scientific discussion.”

According to the review, vaccines were 95% effective against severe disease both from the Delta and Alpha variant, and more than 80% effective at protecting against infection from these variants.

Vaccines are less effective against asymptomatic disease or transmission than against severe disease, according to the review. It added that unvaccinated people are the major drivers of transmission and are at the greatest risk of severe disease.

“Taken as a whole, the currently available studies do not provide credible evidence of substantially declining protection against severe disease, which is the primary goal of vaccination,” said lead author Dr. Ana Maria Henao-Restrepo, a medical officer at the WHO’s Initiative for Vaccine Research.

She said the limited supply of vaccine will save the most lives if made available to unvaccinated people who are at risk of serious disease.

“Even if some gain can ultimately be obtained from boosting, it will not outweigh the benefits of providing initial protection to the unvaccinated,” Henao-Restrepo added. “If vaccines are deployed where they would do the most good, they could hasten the end of the pandemic by inhibiting further evolution of variants.”

Although antibodies in vaccinated people wane over time, the authors noted that it does not predict that a lack of protection against severe disease.

Protection against severe disease is not only from antibody responses, which might be short-lived for some vaccines, but also by memory responses and cell immunity, which are longer-lived, the researchers explained. If boosters are needed, they would be in circumstances where the benefits outweigh the risks.

Even without any loss of effectiveness, however, increasing success in delivering vaccines to large populations will lead to increasing more widespread immunization, the researchers said. As a result, more cases that do occur would be less severe breakthrough infections, especially if vaccination leads people to change their behavior.

But, they added, the ability of vaccines to elicit an antibody response against current variants indicates that these variants have not yet evolved so much they are likely to escape the protection by the vaccines.

If boosters are needed, the researchers said, they would most likely be developed against specific variants not covered by current vaccines. This strategy is like that for flu shots, which changes as flu strains evolve from year to year.

Source: HealthDay

Study: Avocados Change Belly Fat Distribution in Women

Liz Ahlberg Touchstone wrote . . . . . . . . .

An avocado a day could help redistribute belly fat in women toward a healthier profile, according to a new study from the University of Illinois Urbana-Champaign and collaborators.

One hundred and five adults with overweight and obesity participated in a randomized controlled trial that provided one meal a day for 12 weeks. Women who consumed avocado as part of their daily meal had a reduction in deeper visceral abdominal fat.

Led by Naiman Khan, an Illinois professor of kinesiology and community health, the researchers published their study, funded by the Hass Avocado Board, in the Journal of Nutrition.

“The goal wasn’t weight loss; we were interested in understanding what eating an avocado does to the way individuals store their body fat. The location of fat in the body plays an important role in health,” Khan said.

“In the abdomen, there are two kinds of fat: fat that accumulates right underneath the skin, called subcutaneous fat, and fat that accumulates deeper in the abdomen, known as visceral fat, that surrounds the internal organs. Individuals with a higher proportion of that deeper visceral fat tend to be at a higher risk of developing diabetes. So we were interested in determining whether the ratio of subcutaneous to visceral fat changed with avocado consumption,” he said.

The participants were divided into two groups. One group received meals that incorporated a fresh avocado, while the other group received a meal that had nearly identical ingredients and similar calories but did not contain avocado.

At the beginning and end of the 12 weeks, the researchers measured participants’ abdominal fat and their glucose tolerance, a measure of metabolism and a marker of diabetes.

Female participants who consumed an avocado a day as part of their meal had a reduction in visceral abdominal fat – the hard-to-target fat associated with higher risk – and experienced a reduction in the ratio of visceral fat to subcutaneous fat, indicating a redistribution of fat away from the organs. However, fat distribution in males did not change, and neither males nor females had improvements in glucose tolerance.

“While daily consumption of avocados did not change glucose tolerance, what we learned is that a dietary pattern that includes an avocado every day impacted the way individuals store body fat in a beneficial manner for their health, but the benefits were primarily in females,” Khan said. “It’s important to demonstrate that dietary interventions can modulate fat distribution. Learning that the benefits were only evident in females tells us a little bit about the potential for sex playing a role in dietary intervention responses.”

The researchers said they hope to conduct a follow-up study that would provide participants with all their daily meals and look at additional markers of gut health and physical health to get a more complete picture of the metabolic effects of avocado consumption and determine whether the difference remains between the two sexes.

“Our research not only sheds a valuable light on benefits of daily avocado consumption on the different types of fat distribution across genders, it provides us with a foundation to conduct further work to understand the full impact avocados have on body fat and health,” said study coauthor Richard Mackenzie, a professor of human metabolism at the University of Roehampton in London.

“By taking our research further, we will be able to gain a clearer picture into which types of people would benefit most from incorporating avocados into their diets and deliver valuable data for health care advisers to provide patients with guidance on how to reduce fat storage and the potential dangers of diabetes,” Mackenzie said.

Source: University of Illinois at Urbans-Champaign

Chart: Association of Global Crude Oil, Atmospheric Pollutants and Pesticide Production with Population Growth and Chronic Disease Trends

Enlarge image . . . . .

Source: Elsevier

Study: Healthier Supermarket Layout Improves Customers’ Food Choices

New research from the University of Southampton shows that removing confectionery and other unhealthy products from checkouts and the end of nearby aisles and placing fruit and vegetables near store entrances prompts customers to make healthier food purchases.

The study, led by Dr Christina Vogel, Principal Research Fellow in Public Health Nutrition and Janis Baird, Professor of Public Health and Epidemiology at the University’s MRC Lifecourse Epidemiology Centre, was conducted in partnership with the national supermarket chain Iceland Foods Ltd. The trial took place in a selection of Iceland stores in England and monitored store sales as well as the purchasing and dietary patterns of a sample of regular customers.

The results showed store-wide confectionery sales decreased and fruit and vegetable sales increased when non-food items and water were placed at checkouts and at the end of the opposite aisles, and an expanded fruit and vegetable section was repositioned near the store entrance. Beneficial effects were also observed for household fruit and vegetable purchasing and individual dietary quality. Full details are presented in the open-access journal PLOS Medicine from 24th August 2021.

When talking about the results of the study Dr Vogel said “Altering the layouts of supermarkets could help people make healthier food choices and shift population diet towards the government’s dietary recommendations. The findings of our study suggest that a healthier store layout could lead to nearly 10,000 extra portions of fruit and vegetables and approximately 1,500 fewer portions of confectionery being sold on a weekly basis in each store.”

This research is more comprehensive than previous studies testing whether placement strategies can promote healthier food purchasing which have been limited in scope, for example including only a single location (i.e. checkouts) or placing healthy and unhealthy products together. This study went further, aiming to reduce customers exposure to calorie opportunities by placing non-food items at checkout and aisle-ends opposite and measuring effects on store sales, customer loyalty card purchasing patterns and the diets of more than one household member.

Matt Downes, Head of Format Development at Iceland said “We have been pleased to support this long-term study and the evaluation of how product placement in supermarkets can affect the diets of our customers. We know that childhood obesity is a growing issue and the retail industry has its part to play in tackling this. We hope that the outcomes of the study provide insights for the wider retail industry and policy makers about the impact of store merchandising on purchasing decisions.”

Prof Baird added “These results provide novel evidence to suggest that the intended UK government ban on prominent placement of unhealthy foods across retail outlets could be beneficial for population diet, and that effects may be further enhanced if requirements for a produce section near supermarket entrances were incorporated into the regulation.”

Source: EurekAlert!

Breastfeeding May Strengthen Preterm Baby’s Heart

Breast milk can give preemies’ hearts a big boost, a groundbreaking study suggests.

“This study … adds to the already known benefits of breast milk for infants born prematurely,” said study leader Dr. Afif El-Khuffash, a clinical professor of pediatrics at the Royal College of Surgeons in Ireland (RCSI) University of Medicine and Health Sciences in Dublin.

He said the findings offer the first evidence of a link between early diet in preemies and heart function over the first year of life.

Because preemies’ heart function is significantly lower than that of healthy full-term babies, they are more likely to develop heart problems later in life — including heart disease, heart failure, systemic and pulmonary high blood pressure, the researchers said. They also have a higher risk of death from heart disease.

This study of 80 preterm infants found that those initially fed only their mother’s breast milk had improved heart function at 1 year of age, and that it approached the level found in healthy full-term babies.

Specifically, preemies who received high amounts of mother’s milk during the first weeks of life had healthier heart structures and functions and a better heart response to stress at age 1 than did preemies who were given higher amounts of formula.

These improvements were apparent before babies left the hospital and persisted up to age 1, according to findings published in the journal JAMA Network Open.

“Preterm infants have abnormal heart function. However, those who are fed their mother’s own milk demonstrate recovery of their heart function to levels comparable to healthy term born infants,” El-Khuffash said in a college news release. “Preterm infants fed formula do not demonstrate this recovery.”

Source: HealthDay