More weight loss is also generally accompanied by greater harms including stomach and bowel symptoms, fatigue, and loss of lean (muscle) mass – and improvements are not sustained after stopping treatment.

Several drugs for adults with overweight or obesity produce substantial weight loss, but most have not been compared directly in head-to-head trials, leaving uncertainty about the broader balance of benefits and harms.

To address this, researchers searched scientific databases for randomised controlled trials comparing one or more drugs with lifestyle changes, placebo, or another drug.

They found 262 eligible trials involving 99,791 participants (average age 49; 63% female; average BMI 35) that evaluated 19 currently available and emerging obesity drugs with follow-up from 12 to 172 weeks.

Benefits included changes in body weight, fat mass, and quality of life, while potential harms included changes in lean mass, gastrointestinal adverse events, gallbladder related disorders and fatigue.

The trials were of varying quality, but the researchers were able to assess the certainty of evidence using the recognised GRADE system.

Compared with lifestyle changes alone, the largest weight loss after one year was with tirzepatide (14.9%) and CagriSema (14.8%), followed by oral semaglutide (10.9%), orforglipron (9.9%), subcutaneous semaglutide (9.8%), and phentermine-topiramate (8.1%).

Emerging drugs – including retatrutide, ecnoglutide, and mazdutide – showed large effects on weight loss but are supported by low or very low certainty evidence.

Greater weight loss was consistently accompanied by higher rates of side effects and treatment discontinuation, which the authors say indicates a clear benefit-harm trade-off.

Tirzepatide reduced fat mass the most (by 25.7%) but also lean mass the most (8.3%). Subcutaneous semaglutide was the only drug associated with a reduced risk of death from any cause (19%), heart attack (28%), and heart failure (57%). Tirzepatide also reduced heart failure risk by 51%.

No drug convincingly reduced kidney failure or showed clinically important improvements in quality of life.

The authors acknowledge that most trials had relatively short follow-up, limiting conclusions about long term safety, quality of life, and effects on heart and kidney health. In addition, evidence for several newer drugs was sparse and of low certainty, and trial populations may not fully represent real world patients.

However, they say this review provides a comprehensive and up-to-date comparison of currently available and emerging obesity drugs across a broad set of outcomes important to patients, clinicians, and policymakers.

They conclude: “Treatment decisions for obesity should be individualised, balancing expected benefits, harms, treatment burden, costs, availability, and patient preferences.”

This study represents an important step in providing comparative information to inform patient-clinician discussions about obesity drugs in this rapidly evolving landscape of treatment options, say researchers in a linked editorial.

And they suggest future studies that incorporate individual characteristics, as well as long term outcomes, such as mortality, should provide additional data to inform individualised decision making.

A modelling study found that using vegetables, beans and eggs instead of processed and unprocessed meat and dairy could deliver environmental and health benefits without increasing the overall cost of diets.

Experts say making healthier, more sustainable food options more accessible and convenient could help accelerate progress towards climate and public health goals.

Scientists from the University of Edinburgh assessed 33 different ways of meeting the UK Climate Change Committee’s recommendations for sustainable diets.

The research examined the impact of dietary changes on greenhouse gas emissions, land and water use, nutrient intake, diet costs and health conditions including type 2 diabetes and cardiovascular disease.

Across all scenarios modelled, reductions in meat and dairy consumption were associated with improvements in health outcomes and environmental indicators, the study found.

Researchers found that even small, gram-for-gram substitutions in everyday meals such as sandwiches and pasta dishes could produce meaningful long-term benefits for both people and the planet.

Replacing some meat with a variety of alternative foods did not adversely affect nutrient intake. While lower dairy consumption could considerably reduce iodine intake among some groups, this could be addressed through iodine fortification of plant-based dairy alternatives, experts say.

The findings challenge perceptions that more sustainable diets are necessarily more expensive, with most dietary changes having little impact on overall food costs.

The study suggests that targeting people who consume the largest amounts of processed and unprocessed red meat could deliver the greatest benefits. Rather than reducing consumption evenly across the population, helping high consumers move towards lower intakes was predicted to prevent almost 60,000 cases of type 2 diabetes over a 10-year period while also achieving greater environmental gains.

All modelled dietary pathways resulted in lower greenhouse gas emissions as well as reductions in land and water use.

The research also found that emissions associated with food consumption by adults in Scotland, including the carbon footprint of imported food, exceed emissions from agricultural production in Scotland. The findings highlight the importance of dietary change alongside efforts to reduce emissions from agriculture.

Dr Joe Kennedy, from the University of Edinburgh’s Division of Global Agriculture and Food Systems, said: “The findings show that modest, realistic dietary changes, when scaled across a population, can deliver substantial benefits to people and the planet. Making healthier, sustainable options more available and convenient will be key to enabling such change.”

The study was carried out in collaboration with colleagues from the University of Oxford and Food Standards Scotland.

The study is published in the journal Nature Food: https://www.nature.com/articles/s43016-026-01384-3 [URL will become active after embargo lifts]. It was funded by the Wellcome Trust and Food Standards Scotland.

For further information, please contact: Guy Atkinson, Press and PR Office, 07816 392904, guy.atkinson@ed.ac.uk

The research findings have been published in the renowned journal Nature Communications: Dual human milk oligosaccharide-fibre utilisation is a selection cue for the weaning gut microbiome.

“We have long known that breastfeeding is important for infants’ health. What is new is that we can now explain how the sugars in breast milk, HMOs, also help to select the bacterial communities associated with a healthy gut microbiota later in life. This underlines the importance of combining breastfeeding with solid baby food at this stage of child’s development,” says Maher Abou Hachem, professor at DTU Bioengineering and senior author of the study.

The study reveals a previously unknown mechanism that gives specific gut bacteria an advantage in the competition to inhabit the infant’s gut during weaning, because they are endowed to metabolise both HMOs from breast milk and fibres from plant-based foods.

The results suggest that the weaning period is a crucial developmental window, during which the combination of breast milk and solid food, promotes the maturation of the gut microbiota to the adult-like community that is maintained during adulthood. On the long term, this new knowledge may contribute to the development of better nutritional solutions for infants and strengthen our understanding of how early nutrition affects health later in life.

“The findings are important in daily clinical practice as an additional justification to the already strong emphasis on promoting the mother’s own milk production and breastfeeding when infants and young children are admitted to a neonatal intensive care unit due to preterm birth or critical illness,” says Consultant Lise Aunsholt from the Department of Intensive Care for Newborns and Young Children at Rigshospitalet.

“It is encouraging to know that when we advise a mother to continue breastfeeding after discharge – and for as long as possible during the transition to solid foods – this will potentially have a positive impact on the child for the rest of their life,” she says.

According to the researchers, the study shows that breast milk not only supports the infant’s nutrition during infancy but also helps to select the bacteria that become a permanent part of the gut microbiota later in life.

Close collaboration between DTU and TUH

The study was carried out in close collaboration between researchers from DTU and clinical research environments at the Technical University Hospital (TUH – see fact box)

The researchers analysed the changes in bacteria and their genes over the weaning phase. This gave them insight into which bacteria were present and what the bacteria were doing. At the same time, the researcherscultured the bacteria in the laboratory under conditions resembling the environment in the human gut. In this way, they were able to identify the bacteria capable of metabolising both HMOs from breast milk and dietary fibres from solid food.

“The collaboration between DTU’s technological and biological expertise and the clinical environments at TUH has been crucial in enabling us to link knowledge about the bacteria’s functions to the development of the gut microbiota in children. This provides unique insight into how early dietary choices affect health later in life,” says Maher Abou Hachem.

Could pave the way for new nutritional solutions

The researchers believe that this new knowledge sets the stage for the development of future nutritional solutions for infants and targeted interventions that support the establishment of healthy gut bacterial community.

The results also suggest that the weaning period may be a crucial time for preventive measures against diseases that are later in life associated with disturbances in the gut microbiota.

Robert Fletcher of the University of Cambridge, Health Data Research UK and The George Institute, and study co-lead says:

“Levels of obesity in England have worsened since the pandemic, with nearly one in three people now affected.

“We’re also seeing large disparities across the country: the percentage of adults affected by obesity in northeast England is six times higher than in central London. Differences on this scale are rarely seen in other areas of public health. The rise in new cases among young adults of childbearing age is especially concerning. Beyond the implications for their own long-term health, obesity is associated with infertility, adverse pregnancy outcomes, and child obesity, which may perpetuate intergenerational cycles of health inequality.”

Key findings:

Obesity is rising: Rates of new obesity cases increased overall by 4% in 2025 compared with before the COVID-19 pandemic.

Young adults hit hardest: The largest increases over time were seen in younger adults. Rates of new obesity cases rose by almost 20% in those aged 30-39, and by 16% in those aged 20-29, while rates fell among adults aged 60-79.

Risk rises with deprivation: Over the study period, rates of new obesity cases were 35% higher for people with the highest socioeconomic deprivation (those with the lowest incomes, highest unemployment, and poorest housing) compared with people with the lowest socioeconomic deprivation. The gap was wider still for women, where new cases were 54% higher among the most deprived, and widest for Asian women, at 94% higher.

Ethnicity and deprivation compound: The percentage of people living with obesity ranged from 4% among the most affluent White men aged 18–19 to 66% among the most socioeconomically deprived Black women aged 60–69 – nearly double the figure for the least-deprived White women of the same age.

Large geographical differences: The percentage of people affected by obesity in some areas of northeast England (48%) was nearly six times higher than that seen in the most affluent parts of central London (8.5%). The steepest increases over time were seen in areas with the lowest GDP per capita.

The person-level data analysed in this study has all direct identifiers such as names and NHS numbers removed before researchers access the data, which is then only accessible within NHS England’s Secure Data Environment. The data is only accessible by approved researchers working on approved, COVID-19 related research projects.

The researchers’ definition for obesity was a recorded body-mass index (BMI) of 30 or above, or a clinician’s diagnosis of obesity in a person’s health records. Their findings from this electronic health record study correspond well with the NHS Health Study for England, which samples households across the country, giving confidence in the extra depth of the insights this study is able to provide.

They looked at rates of new cases of obesity (incidence) and the percentage of people with obesity (prevalence) in the general population, as well as differences across sociodemographic groups and geographical regions.

Obesity is now more common than hypertension (high blood pressure) in the UK, and nearly three times as common as smoking. It is a chronic, complex disease linked with a whole host of conditions, including heart disease, stroke, cancer, diabetes, and kidney failure. As well as affecting individuals’ mental wellbeing, and placing growing pressure on both the healthcare system and the economy. These findings highlight the scale and urgency of the obesity crisis, and how it has worsened since the COVID-19 pandemic.

GLP-1 receptor agonist drugs, like Ozempic/Wegovy and Mounjaro, are known to be effective in managing obesity and are being more widely prescribed and used. The study did not set out to examine their impact.

“We don’t see any obvious reduction in obesity in our data following the introduction of GLP-1 receptor agonists, at least not within the current study period,” says Robert Fletcher. “However, the drugs on their own are unlikely to be the answer. At present, the majority are privately prescribed and the jabs are expensive, which poses a barrier for people from disadvantaged backgrounds. We need deep-seated change to the many social and economic factors that drive obesity in the first place.”

Naveed Sattar, one of the co-authors, Professor of Cardiometabolic Medicine at the University of Glasgow and Chair of the Obesity Health Care Goals Programme, agrees:

“Obesity is not primarily about will power. These new, powerful data indicate that those most at risk frequently reside in the most obesogenic environments and likely have the least agency to withstand such environments. To achieve lasting change, the UK must expand access to new treatments faster but also fundamentally reshape food and activity environments so that healthier choices occur with minimal conscious effort. Failure to act will drive further rises in multimorbidity and human suffering, with profound consequences for the NHS and the wider economy.”

Study co-lead Angela Wood, Professor at the University of Cambridge and Associate Director at the British Heart Foundation Data Science Centre, says:

“The COVID-19 pandemic has had a lasting impact on health and lifestyle behaviours. By analysing electronic health records from the entire adult population of England before, during, and after the pandemic, we have generated the most comprehensive evidence to date on how obesity risk and burden are increasingly diverging across multiple dimensions of inequality. These findings underscore the critical importance of secure access to whole-population health data to enable research, surveillance, and timely action to address widening health inequalities.”

The study, funded by the Wellcome Trust, Health Data Research UK, the British Heart Foundation, the National Institute for Health and Care Research Cambridge Biomedical Research Centre, the Cambridge British Heart Foundation Centre of Research Excellence, has been published in The Lancet Diabetes & Endocrinology.

Overall, the plant-based products contained more additives, more ingredients and more E-numbers than their animal-based counterparts.

A team from the Institute for Optimum Nutrition in London (a provider of university-accredited courses in nutrition) led the research which is published today in the peer-reviewed journal, Food Additives & Contaminants: Part A.

Joseph Whittaker, Vivienne Alexa Robinson and Elouise Redmayne looked at 71 like-for-like pairs of animal-based and plant-based products from an unidentified UK supermarket, that were available on the shelves in late-October 2025.

The team matched the products with each other based on a variety of factors such as the ingredients, packaging, and size, to achieve the closest match possible. So, for instance, almond milk was paired with normal milk, vegan brownies with dairy-based brownies, and plant-based meat with regular meat. Other products included were lasagne, coleslaw, pesto, mayonnaise, yoghurt and cake.

The product range used was marketed as plant-based, but all the products were also vegan.

Overall, results showed:

• the total number of food additives in the plant-based products was 199 compared with 100 in their corresponding animal-based equivalents.
• the total ingredients in the plant-based range was 1,566. In the animal-based range, it was 1,110.
• there were 39 E-numbers in the plant-based range and 31 in the animal-based set. (In total, 50 E-numbers were identified, of which 20 appeared in both groups.)

Across additives, ingredients and E-numbers, the difference between plant-based and animal-based was most stark in dairy, meat and fish products and their plant-based replacement.

“We found roughly twice as many food additives in the total sample of plant-based products compared to animal-based ones: 199 versus 100,” states senior author Joseph Whittaker, a lecturer at ION.

“However, even though we found that plant-based products had more food additives this does not necessarily mean an increased health risk. First, we only analysed one product range so we can’t make generalisations to all plant-based products. Second, we didn’t assess the quantity or concentration of food additives used, nor how much or how often people eat these products, so, essentially, we don’t know the level of exposure of food additives from these products. And last, all food additives used in these products have passed UK food safety regulations.”

Plant-based eating is on the rise. UK survey data shows a trend of declining meat consumption – from 103.7 to 86.3 g per capita per day in the decade to 2018–2019*. US dietary survey data reveals that the proportion of adults consuming a plant-based diet increased from 14.4% to 17.2% between 1999–2000 and 2017–2020**. And a Flemish study found that the number of adult ‘flexitarians’ rose from 5.3% to 9.2% from 2011 to 2020***.

Joseph adds: “Our study comes at a particularly important time as plant-based diets are increasing in popularity and more people are turning to plant-based alternatives products, but people are also concerned about the number of food additives in their food. This is known as the ‘clean label trend’. They are also trying to avoid ultra-processed foods and their potential negative effects upon health, although our study wasn’t focused on this.”

The main limitation of the research carried out was the limited sample of products used – from just one supermarket range.

The author team suggest future research should aim to see if the findings are replicated in other product ranges, including different brands and products available in other countries. “If future findings are consistent with ours, we could start to generalise more about plant-based products and be more certain in our conclusions,” Joe adds.

“One really interesting area that our study did not assess is the level of processing of plant-based products” he concludes. “It may be the case that many of these products are highly processed, and people switching to a plant-based diet and using a lot of these products, may end up on a highly refined diet. I think further research should test this, particularly as these diets are so popular now.

“I would argue that plant-based dieters should focus on whole-foods that are naturally plant-based, rather than trying to replicate animal-based foods. By necessity many plant-based alternative foods use food additives and refined ingredients, as foods like plant-based meat do not exist in nature.”

Research cited: * Stewart et al. 2021. **Sullivan et al. 2024. *** Deliens et al. 2022.

The analysis found that while healthy behaviour and lifestyle interventions remain an essential foundation of any effective weight management programme — delivering meaningful weight loss and improvements in body composition on their own — adding pharmacotherapy produced the strongest outcomes. Crucially, the study’s authors characterise medication not merely as a supplementary tool, but as a core component of treatment when combined with lifestyle change.

The review assessed short-term outcomes typically measured over six to twelve months, tracking improvements in body mass index (BMI) and BMI z score, a metric used to contextualise weight relative to age and sex in children and adolescents. Long-term sustainability and safety were also monitored across the included studies.

The findings come as obesity rates in children and adolescents continue to rise globally, placing growing pressure on clinicians and health systems to identify effective, evidence-based treatment approaches. The results suggest a shift in how pharmacotherapy should be framed in paediatric obesity care — not as a last resort or add-on, but as an integral element of a combined strategy.

The study was led by corresponding author Bjorn T. Tam, PhD, and is published in JAMA Pediatrics (doi:10.1001/jamapediatrics.2026.2248). The full text is freely accessible here.

UVA researchers led by Jason Papin, PhD, analyzed more than 350 over-the-counter probiotics sold at the three largest pharmacy chains in the United States – CVS, Walgreens and Walmart. Those 352 products were found to contain, collectively, only 36 unique species of bacteria. The most common species were forms of Lactobacillus, a type of bacteria commonly found in yogurt.

More than half the products contained only one probiotic species. The products with the most unique species topped out at 17. Some brands maintained a consistent number of bacterial strains across products, while others did not.

Based on their analysis, the scientists concluded that there was no real consistency in the combination of species used to support gut health, vaginal health or other health claims.

“It is truly fascinating to discover that these probiotic bacteria hold a unique, specialized niche among the trillions of microbes in and on the human body,” said Glynis Kolling, PhD, a research faculty member in UVA’s Department of Biomedical Engineering who works closely with Papin. “By combining our advanced methods, we have the potential to vastly expand the pool of beneficial bacteria and pave the way for targeted solutions to support human health.”

Targeting the Microbiome

We have at least as many microorganisms living on and inside us than we have cells in our bodies. Scientists have increasingly come to appreciate the role these microorganisms – collectively known as the microbiome – play in maintaining our health. We can get beneficial bacteria from our diets, such as from yogurt and fermented foods, but there has also been an explosion in “probiotic” products over the last two decades.

So far, the federal Food and Drug Administration has approved only two microbial products for therapeutic purposes, and both are used to treat recurrent C. difficile infections in the colon. Supplements, however, are not regulated as strictly as drugs in the United States, and there is limited understanding of connections between bacteria and marketed use for many probiotic products, the UVA researchers found.

To improve the effectiveness of probiotic products, Papin and his team have developed HaPaPro, a collection of more than 1,000 computer models of bacterial metabolism. They used these models to see if they could identify probiotics with the potential to improve women’s vaginal health.

The vaginal microbiome is a natural ecosystem of bacteria, fungi and other microbes that help support health. Bacterial vaginosis occurs when this natural ecosystem is disrupted, leading to pregnancy complications, pelvic inflammatory disease, higher risk of sexually transmitted disease and general discomfort. The researchers were able to use their models to identify microbes that have the potential to help prevent bacterial vaginosis.

The successful results, Papin says, demonstrates HaPaPro’s potential for identifying ways to manipulate the microbiome will have concrete benefits. Such insights, he hopes, will lead to better probiotic products that deliver on their promises.

“It is remarkable how much microbes play a role in human health and well-being,” Papin said. “I love seeing how computational models of these complex biological systems are leading to new ideas for therapies and helping us understand such fundamental biological processes.”

Findings Published

The researchers have published their findings in the scientific journal Nature Microbiology. The research team consisted of Emma M. Glass, Kolling and Papin. The scientists have no financial interest in the probiotic industry, but Papin disclosed he has a stake in Cerillo, the manufacturer of instrumentation used in some of the analyses.

The work was supported by the National Science Foundation, grant 1842490, and the National Institutes of Health, grants T32 GM-145443-1, R01-AI154242 and R01-AT010253.

UVA’s Department of Biomedical Engineering is a joint program of the School of Medicine and the School of Engineering and Applied Science.

To keep up with the latest medical research news from UVA’s Paul and Diane Manning Institute of Biotechnology and School of Medicine, bookmark the Making of Medicine blog.

DOI 10.1038/s41564-026-02380-w 

Image: University of Virginia School of Medicine researchers led by Jason Papin, PhD, analyzed more than 350 over-the-counter probiotics sold at the three largest pharmacy chains in the United States. Those 352 products were found to contain, collectively, only 36 unique species of bacteria. The most common species were forms of Lactobacillus, a type of bacteria commonly found in yogurt. 

View more Credit: UVA Health

The longitudinal study tracked 422 women from the Michigan State University Twin Registry who were taking combined oral contraceptives or contraceptives that include both synthetic estrogen and progestin hormones.

These contraceptives include active pills that contain synthetic hormones including synthetic estrogen and progestin, as well as inactive pills, or hormone-free placebo pills. The inclusion of both active and inactive pills provided a unique opportunity for researchers to examine changes in binge eating when a woman was taking her active versus inactive pills.

For 49 consecutive days, the researchers tracked changes within women for emotional eating, a form of binge eating where individuals overconsume food in the presence of negative emotions.

The study, published in JAMA Network Open, found significantly increased emotional eating when women were taking active versus inactive pills. These findings were present in the full sample of women as well as in women who reported current or past histories of clinical levels of binge eating.

Previous research has suggested ovarian hormones (natural estrogen and progesterone) play a significant role in binge-eating risk in females. These new findings suggest that synthetic hormones in combined oral contraceptives may also heighten risk.

“These findings are important for highlighting the potential negative impact of combined oral contraceptives in women. Nonetheless, it’s important to note that not every woman in the study developed binge eating — they are safe for many women, and it’s likely that the risk is targeted to those with other risk factors,” said Kelly Klump, lead author of the study and MSU Research Foundation Distinguished Professor in MSU’s Department of Psychology. “Future studies are needed to better identify who is at risk and inform personalized medicine approaches to women’s health.”

The study also found that the act of reporting on binge eating every day, otherwise known as self-monitoring, helped decrease binge eating for the participants in the study. These decreases were observed even when women were taking active hormone pills.

“We found that self-monitoring was an effective tool in mitigating risk for women in the study,” said Klump. “The more we can equip women with tools and educate medical providers about these risks, the more effective care can be given.”

By educating medical practitioners about the effects of combined oral contraceptives on binge eating and the value of self-monitoring, the researchers hope that a more personalized approach can help those at risk.

Written by Shelly DeJong

“Our study asked two questions that haven’t been well answered until now: How many people with type 2 diabetes taking GLP-1 medications actually stop using them? And how many restart them?” said Sainikhil Sontha, M.S., a research associate at Boston University School of Public Health in Boston, Mass.

The researchers performed a retrospective cohort study using Komodo Health U.S. claims data (January 2019 to June 2025). The group included adults aged 18 to 64 years with a BMI ≥25 kg/m² and type 2 diabetes who started liraglutide, semaglutide, or tirzepatide, and had previously enrolled within the last year with more than 6 months of follow-up.

Discontinuation was defined as having more than a 60-day gap in filling their GLP-1 prescriptions. Getting a new fill after discontinuation was considered as reinitiation.

“Using insurance records from more than 60,000 Americans with type 2 diabetes, we found that about 4 in 10 patients stopped their GLP-1 medication within the first year, and nearly 6 in 10 had stopped by the end of two years,” Sontha said.

But they also found something encouraging.

“More than half of those who stopped restarted therapy within a year (41.5%), and nearly two-thirds did so within two years (58%),” Sontha said. “This suggests that for many patients, these medications aren’t being abandoned permanently; use is more start-and-stop than most people assumed.”

Using Cox proportional hazards models, they also took sociodemographic, clinical and provider-level predictors into consideration.

Sontha and colleagues found that those on Medicaid or Medicare, Black patients, and those experiencing nausea or other stomach-related side effects (37%) were more likely to discontinue a GLP-1 medication within a year.

People were 10% less likely to stop if their first GLP-1 medication was prescribed by an endocrinologist.

What’s more, people taking newer medications like tirzepatide were 41% less likely to discontinue than those taking older drugs like liraglutide. Semaglutide users were 28% less likely to discontinue anti-obesity medication use than those taking older medications.

“This research matters because consistent use of these medications is what produces their protective effects,” Sontha said. “Stopping early may mean missed opportunities to prevent heart attacks, kidney disease progression and other complications.”

The researchers hope that these findings give providers, insurers and policymakers an idea of which patients need more support to stay on GLP-1 medications, he said.

Chile ranks among the highest countries globally for rates of childhood overweight and obesity [1]. To combat this issue, in 2016 Chile implemented one of the world’s most comprehensive and ambitious food policies, the Food Labelling and Advertising Law (FLAL) [2].

The FLAL targets foods and drinks high in sugars, saturated fats, salt, or calories through three core measures: mandatory front-of-package warning labels in the form of black octagons (images available here), restrictions on the sale of such products in schools, and limits on food marketing directed at children.

Prof Guillermo Paraje, Professor of Economics, Universidad Adolfo Ibáñez Business School (Chile), says, “Although individual national measures like sugar taxes on soft drinks have been associated with improved health outcomes, this is the first study to plausibly demonstrate that a package of policies can reduce early childhood overweight/obesity risk at the national level.

“These results offer strong evidence for policymakers around the world. They support mandatory front-of-pack nutrition warning labels, restrictions on unhealthy food in schools, and marketing bans as effective, practical ways to tackle the childhood obesity epidemic.”

National data on more than 300,000 schoolchildren aged four to six in Chile was used to compare children’s weight from the years before the introduction of FLAL with the weight and size of children in the same school grades after the first phase of the law came into place in 2016.

The study found that children who had been at school for 18 months after the introduction of FLAL Phase 1 were less likely to be overweight or have obesity than those in the same grades before FLAL. Girls had a 2.9% lower risk of overweight or obesity (a reduction of 1.4 percentage points from a pre-FLAL rate of 47.7%) while boys had a 2.4% lower risk (a reduction of 1.2 percentage points from a pre-FLAL rate of 52%.)

The study also found a plausible causal impact in the cohort of schoolchildren aged four to six after only six months of the FLAL Phase 1; girls had a 1.9% lower risk of overweight or obesity (a reduction of 0.9 percentage points from a pre-FLAL prevalence of 47.4%) and boys a 2.2% lower risk (a reduction of 1.2 percentage points from a pre-FLAL prevalence of 52%).

Phases 2 and 3 of FLAL set stricter limits on sugars, saturated fats, salt, or calories. These phases were introduced in 2018 and 2019, so they did not impact the study’s results.

Dr Nieves Valdes, Associate Professor of Economics, Universidad Adolfo Ibáñez Business School (Chile), says, “Although the reduction in obesity and overweight risk among young school children may seem modest, it is likely that the further tightening of the law in later years will have increased the impact, especially given evidence that there was a greater drop in sales of labelled food products during Phase 2 of the FLAL compared to Phase 1.”

“Additionally, even a small weight reduction for children who have overweight or obesity is likely to bring meaningful long-term health benefits, given the strong links between childhood obesity and later risk of obesity, diabetes, hypertension, and cardiovascular disease, as well as evidence that early prevention can substantially lower these risks.”

The researchers note some limitations of their studies, including that the plausible causality of the relationship relies on the assumption that, if the FLAL hadn’t been introduced, the two cohorts of school children would have followed the same nutrition trends, which cannot be tested although support for the assumption was provided through pre-policy trends. Additionally, the children’s weight was collected by school staff who, although trained for this task, may not achieve the same precision typically found in primary health care settings.

Writing in a linked Comment, Professor Simone Pettigrew and Dr Daisy Coyle, The George Institute for Global Health (Australia), who were not involved in the study, say, “In a policy environment where industry opposition constitutes a formidable obstacle to the implementation of health-promoting policies, high-quality, real-world evidence is critical. […] the research results strengthen the case for governments to move beyond incremental, single-policy approaches and to instead implement comprehensive, integrated strategies to improve food environments. In particular, the results highlight the potential for policy suites including mandatory warning labels and marketing restrictions on unhealthy foods and school food minimum standards to produce meaningful outcomes.”

The poll included 2,200 U.S. adults surveyed May 26-27, 2026. When asked, “What is the effect of the following foods on an individual’s blood cholesterol level?” roughly half correctly answered that beans, whole grains, and soy products reduce risk, but 36% said chicken, 26% said lean cuts of red meat, and 18% said eggs also decrease a person’s risk of developing high cholesterol.

“Americans consume over 100 pounds of chicken each year — more than double the amount eaten in 1980.  Unfortunately, more than one in three people inaccurately believe that consuming chicken actually protects against elevated cholesterol,” said Heather Shenkman, MD, an interventional and preventive cardiologist in Encino, Calif. “In reality, meat and dairy products, which also includes chicken, contribute to artery-clogging hyperlipidemia — a symptomless public health crisis affecting one in four U.S. adults — which is a leading cause of cardiovascular disease, heart attack, and stroke.”

Chicken is not a healthy choice. It raises cholesterol levels as much as red meat. In 2019, researchers tested the effects of low-saturated-fat diets that drew their protein from red meat (beef and pork), white meat (chicken and turkey), or nonmeat sources (legumes, nuts, grains, and soy products). It turned out that both white and red meat raised LDL cholesterol, compared with plant-based proteins, and did so to about the same extent.

As for eggs, about 60% of their calories are from fat — much of which is saturated fat, which also contributes to heart disease. Eggs are also loaded with cholesterol — about 200 milligrams each. That’s more than double the amount in a Big Mac.

An analysis published in JAMA found that that each 300-milligram dose of dietary cholesterol was associated with an increased risk for cardiovascular disease and mortality by 17% and 18%, respectively. When it came to eggs, each half egg caused a 6% and 8% increased risk, respectively.

“The good news,” said Physicians Committee Registered Dietitian Anna Herby, “is that plant staples like beans, lentils, and soy milk can easily replace meat and dairy. They also taste delicious, and can cut grocery costs.”

When asked, “If you had high cholesterol or wanted to reduce your risk of high cholesterol, would you be willing to try a plant-based diet?” over half of survey respondents said they would.

Studies have shown a multitude of heart-health-related benefits of eating an array of whole grains, fruits, vegetables, and beans and legumes.

A recent study with 22 pairs of identical twins found that a plant-based diet improved heart health in as little as eight weeks. The twins following a plant-based diet experienced lower LDL cholesterol, and they lost more weight than the omnivore twins.

The twin study adds to numerous other published scientific studies showing that a plant-based diet can help people maintain a healthy weight, lower blood pressure, improve heart health, and reduce their risk of diabetes among other benefits. What’s more, replacing meat with plant-based meat alternatives may also be beneficial for heart health.

A new study from researchers at the Food is Medicine Institute at the Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University, published in American Journal of Public Health, suggests the processing itself may play an independent role. The researchers found that people who ate more ultra-processed foods had worse health outcomes, even after accounting for the overall nutritional quality of the foods.

“The findings suggest ultra-processed-food factors beyond nutrients—such as changes to foods’ cellular structure, loss of beneficial chemical compounds, additives, and chemicals from packaging—may create health risks not addressed by traditional nutrition metrics or policies,” said the study’s senior author, Dariush Mozaffarian, cardiologist and director of the Food is Medicine Institute.

For the observational study, the researchers analyzed data from 10 consecutive cycles of the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018, linked to National Death Index through 2018. Study participants had completed one or two 24-hour dietary recalls.

Using a standard classification system, the team grouped foods based on how they were made—from minimally processed food-based ingredients like fruits and vegetables to ultra-processed products made with industrial ingredients and additives not typically used in cooking. The researchers also rated the nutritional quality of foods using a system that scores foods based on their overall healthfulness. Each participant received an overall diet-quality score based on the foods they reported eating. The team then examined how ultra-processed food consumption was linked to current health measures—such as weight, blood sugar, and cholesterol—as well as long-term risk of death.

For every 10% increase in calories from ultra-processed foods, the researchers found worse health markers. People who ate more of these foods tended to have higher body weight, worse blood sugar control, higher blood pressure, and less favorable cholesterol levels. They were also more likely to have conditions such as diabetes, metabolic syndrome, and cancer and had a slightly higher risk of dying during the study period.

These links remained even after researchers accounted for reported foods’ nutrient quality and the amounts of saturated fat, added sugar, or sodium present in the ultra-processed foods. The patterns were largely the same across different subgroups of people.

“Ultra-processed foods make up a substantial portion of the American diet, accounting for more than 50% of adults’ and about 60% of children’s caloric intake,” said Juna Hatta-Langedyk, first author and an undergraduate biology student at Tufts. “Understanding how these foods affect health is a critical public health priority, given the large proportion of the population affected.”

“Addressing structural and policy-related barriers to accessing fresh and minimally processed foods remains critical for promoting dietary changes that improve the health and life span for all Americans,” said Mozaffarian. “Our findings can help inform many current policy efforts, such as a national definition of ultra-processed foods, and multiple states’ endeavors to propose and pass laws addressing ultra-processed foods, including warning labels, bans on certain additives, and limits in school meals.”

Lu Wang, Bingbing Fan, and Peilin Shi from the Friedman School of Nutrition Science and Policy are also co-authors on this study. Research reported in this article was supported by the National Institutes of Health’s National Heart, Lung, and Blood Institute under award number R01HL115189, as well as by an American Diabetes Association’s Pathway to Stop Diabetes award and the Laidlaw Foundation’s Laidlaw Scholars Leadership & Research Programme. Complete information on methodology, limitations, and conflicts of interest is available in the published paper.

The content is solely the responsibility of the authors and does not necessarily represent the official views of the funders.

image: “Addressing structural and policy-related barriers to accessing fresh and minimally processed foods remains critical for promoting dietary changes that improve the health and life span for all Americans,” said Dariush Mozaffarian, cardiologist and director of the Food is Medicine Institute at the Friedman School of Nutrition Science and Policy at Tufts University.

View more Credit: Imani Khayaam for Tufts University