Tag: obesity

Categories : Diet and Nutrition GeneticsTags :

Obesity Genetic Risk Could be Curbed by Practising Restraint

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Photo by Jonathan Borba

Obesity risk genes make people feel hungrier and lose control over their eating, but practisng dietary restraint could counteract this, according to new research from University of Exeter. Published in the International Journal of Epidemiology, the study found that those with higher genetic risk of obesity can reduce the effects that are transmitted via hunger and uncontrolled eating by up to half through dietary restraint.

Lead author psychology PhD student, Shahina Begum said: “At a time when high calorie foods are aggressively marketed to us, it’s more important than ever to understand how genes influence BMI. We already know that these genes impact traits and behaviours such as hunger and emotional eating, but what makes this study different is that we tested the influence of two types of dietary restraint – rigid and flexible – on the effect of these behaviours. What we discovered for the first time was that increasing both types of restraint could potentially improve BMI in people genetically at risk; meaning that restraint-based interventions could be useful to target the problem.”

Genes linked to obesity increase BMI, with up to a quarter of this effect explained by increases in hunger and uncontrolled (including emotional) eating. There are over 900 genes that have so far been identified by researchers as being associated with BMI and several studies suggest these risk genes influence feelings of hunger and loss of control towards food.

This study examined 3780 adults aged between 22 and 92 years old from two UK cohorts: the Genetics of Appetite Study, and Avon Longitudinal Study of Parents and Children. Their weight and height were measured, and they provided a DNA sample via their blood to calculate an overall score for their genetic risk of obesity. They then completed questionnaires to measure 13 different eating behaviours, including disinhibition (a tendency to engage in binge or emotional eating) and over-eating due to hunger.

As expected, researchers found that a higher genetic risk score was associated with a higher BMI, partly due to increased disinhibition and hunger. However, results also found that those who had high levels of dietary restraint reduced those effects by almost half for disinhibition and a third for hunger, suggesting that restraint may counteract some of the effects of genetic risk.

There are different types of dietary restraint, including flexible strategies to rigid strategies, like calorie counting. The study tested the influence of both types of restraint for the first time and found both could potentially improve BMI in people genetically at risk.

Interventions to facilitate dietary restraint could include changing the food environment (by reducing the calorie content or portion size of food) or supporting individuals. To this end, members of the research team have developed a Food Trainer app (https://www.exeter.ac.uk/research/foodt/) to help achieve that. The app works as a game that trains people to repeatedly stop to high calorie food and research suggests this training may be particularly beneficial for those with a higher BMI.

Source: University of Exeter

Categories : Metabolic DisordersTags :

More Adolescents Are Underestimating Their Body Weight

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A study involving more than 745 000 adolescents from 41 countries across Europe and North America identified an increase in the amount of teenagers who underestimate their body weight. Tracking data from 2002 to 2018, the findings, published in Child and Adolescent Obesity, also show fewer adolescents overestimating their weight.

The team of international experts, who carried out the research, warn these shifting trends in body weight perception could reduce the effectiveness of public health interventions aimed at weight reduction in young people.

“During this impressionable age, body weight perception may influence a young person’s lifestyle choices, such as the amount and types of food they eat and their exercise habits,” says lead author Doctor Anouk Geraets, from the Department of Social Sciences, at the University of Luxembourg.

“So it’s concerning that we’re seeing a trend where fewer adolescents perceive themselves as being overweight — as this could undermine ongoing efforts to tackle increasing levels of obesity in this age group. Young people who underestimate their weight and therefore do not consider themselves to be overweight may not feel they need to lose excess weight and, as a result, they may make unhealthy lifestyle choices.”

A person’s perception of their body weight may not accurately reflect their actual weight. A discrepancy in body weight perception (BWP) may either be an underestimation (where actual weight is higher than perceived weight) or an overestimation (where actual weight is lower than perceived weight).

In the present study, the researchers examined survey data from 746,121 11-, 13- and 15-year-olds from 41 countries collected at four-yearly intervals between 2002 and 2018 in the International Health Behavior in School-Aged Children (HBSC), a WHO collaborative study.

The team modeled trends in BWP among adolescents across different countries over time, making adjustments for age, gender, and family socioeconomic status. They found:

  • Underestimation of weight status increased, and overestimation of weight status decreased over time among both sexes, with stronger trends for girls.
  • Correct weight perception increased over time among girls, while it decreased among boys.
  • Changes in correct weight perception, underestimation and overestimation of weight status differed across different countries — but these changes could not be explained by an increase in country-level overweight/obesity prevalence.

The authors speculated that the observed differences between girls and boys in BWP may support the idea there are sex differences in body ideals — and that these body ideals have changed over time. Notably, the increased underestimation and decreased overestimation of weight status over time for girls may be explained by the emergence of an athletic and strong body, as a new contemporary body ideal for both sexes.

“This study has clinical and public health implications. The increase in correct weight perception and the decrease in overestimation may have a positive effect on unnecessary and unhealthy weight loss behaviors among adolescents, while the increase in underestimation might indicate the need for interventions to strengthen correct weight perception,” says lead author Doctor Anouk Geraets.

“More research is now needed to understand the factors underlying these time trends and to develop effective public health interventions.”

While the large number of participating countries is a strength of the present study, but as these only included countries in Europe, the USA and Canada, the results can’t be generalised to other regions. In addition, although steps were taken to adjust the models for certain potential confounding factors, several other factors – such as body image, dieting, changing eating patterns, or migration – may also have played a role in the observed trends over time.

Source: Taylor & Francis Group

Categories : Metabolic DisordersTags :

Even Modest Alcohol Intake Does not Reduce Diabetes, Obesity Risk

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Having only one or two alcoholic drinks per day does not protect against endocrine conditions such as obesity and type 2 diabetes, according to a new study published in the Journal of Clinical Endocrinology & Metabolism.

It is widely accepted that excessive alcohol consumption causes a wide range of health issues and is thus a major public health concern. Whether modest alcohol consumption has beneficial health effects remains controversial, however, due to the limited power of observational studies.

The researchers used mendelian randomisation (MR), which can help to mitigate biases due to confounding and reverse causation in observational studies, and evaluate the potential causal role of alcohol consumption.

“Some research has indicated that moderate drinkers may be less likely to develop obesity or diabetes compared to non-drinkers and heavy drinkers. However, our study shows that even light-to-moderate alcohol consumption (no more than one standard drink per day) does not protect against obesity and type 2 diabetes in the general population,” said Tianyuan Lu, PhD, from McGill University in Québec, Canada. “We confirmed that heavy drinking could lead to increased measures of obesity (body mass index, waist-to-hip ratio, fat mass, etc) as well as increased risk of type 2 diabetes.”

The researchers assessed self-reported alcohol intake data from 408 540 participants in the U.K. Biobank and found people who had more than 14 drinks per week had higher fat mass and a higher risk of obesity and type 2 diabetes. An extra drink per week was associated with an increased of 8% for diabetes risk and 10% for obesity risk.

These associations were stronger in women than in men. No data supported the association between moderate drinking and improved health outcomes in people drinking less than or equal to seven alcoholic beverages per week.

Source: The Endocrine Society

Categories : Mental Health Metabolic DisordersTags :

Obesity Raises Lifetime Risk of Mental Disorders

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Being obese significantly increases the chances of also developing mental disorders. This applies to all age groups, with women at higher risk than men for most diseases, as a recent study of the Complexity Science Hub and the Medical University of Vienna shows. The results were published in the specialist journal Translational Psychiatry.

“We analysed a population-wide national registry of inpatient hospitalisations in Austria from 1997 to 2014 in order to determine the relative risks of comorbidities in obesity and identify statistically significant sex differences,” explains Elma Dervic of the Complexity Science Hub. Consequently, it became evident that an obesity diagnosis significantly enhances the likelihood of a wide range of mental disorders across all age groups – including depression, nicotine addiction, psychosis, anxiety, eating and personality disorders. “From a clinical point of view, these results emphasise the need to raise awareness of psychiatric diagnoses in obese patients and, if necessary, to consult specialists at an early stage of diagnosis,” says Michael Leutner of the Medical University of Vienna.

First diagnosis: obesity

“In order to find out which illness typically appeared prior and subsequently to the obesity diagnosis, we had to develop a new method,” explains Dervic. This allowed the researchers to determine if there were trends and typical patterns in disease occurrence.

In case of all co-diagnoses, with the exception of the psychosis spectrum, obesity was in all likelihood the first diagnosis made prior to the manifestation of a psychiatric diagnosis. “Until now, physicians often considered psychopharmacological medications to cause the association between mental disorders and obesity as well as diabetes. This may be true for schizophrenia, where we see the opposite time order, but our data does not support this for depression or other psychiatric diagnoses,” explains Alexander Kautzky from Department of Psychiatry and Psychotherapy of the Medical University Vienna. However, whether obesity directly affects mental health or whether early stages of psychiatric disorders are inadequately recognised is not yet known.

Women more impacted

Surprisingly, the researchers found significant gender differences for most disorders — with women showing an increased risk for all disorders except schizophrenia and nicotine addiction.

While 16.66% of obese men also suffer from nicotine abuse disorder, this is only the case in up to 8.58% of obese women. The opposite is true for depression. The rate of diagnosed depressive episodes was almost three times higher in obese women (13.3% obese; 4.8% non-obese). Obese men were twice as likely to be affected (6.61% obese; 3.21% non-obese).

Early intervention is key

Since this study now also shows that obesity often precedes severe mental disorders, the findings reinforce its importance as a pleiotropic risk factor for health problems of all kinds. This is especially true for young age groups, where the risk is most pronounced, and for whom the researchers strongly recommend obesity screening.

Source: Complexity Science Hub Vienna

Categories : COVID VaccinesTags :

COVID Vaccination Protection Wanes Faster in People with Obesity

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According to new research from the Universities of Cambridge and Edinburgh, COVID vaccination protection in people with severe obesity wanes faster than in people of normal weight. The study suggests that people with obesity are likely to need more frequent booster doses to maintain their immunity.

Previous studies on COVID vaccines have suggested that antibody levels may be lower in vaccinated people who have obesity and that they may remain at higher risk of severe disease than vaccinated people with normal weight. The reasons for this have, however, remained unclear.

This study, published in the journal Nature Medicine, shows that the ability of antibodies to neutralise the virus (their ‘neutralisation capacity’) declines faster in vaccinated people who have obesity. The findings have important implications for vaccine prioritisation policies around the world.

During the pandemic, people with obesity were more likely to be hospitalised, require ventilators and to die from COVID. In this study, supported by the NIHR Bioresource and funded by UKRI, the researchers set out to investigate how far two of the most extensively used vaccines protect people with obesity compared to those with a normal weight, over time.

A team from the University of Edinburgh looked at real-time data tracking the health of 3.5 million people in the Scottish population as part of the EAVE II study. They looked at hospitalisation and mortality from COVID in adults who received two doses of COVID vaccine (either Pfizer-BioNTech or AstraZeneca).

They found that people with severe obesity (a BMI > 40kg/m2) had a 76% higher risk of severe COVID outcomes, compared to those with a normal BMI. A modest increase in risk was also seen in people with obesity (30-39.9kg/m2), which affects a quarter of the UK population, and those who were underweight. ‘Break-through infections’ after the second vaccine dose also led to hospitalisation and death sooner (from 10 weeks) among people with severe obesity, and among people with obesity (after 15 weeks), than among individuals with normal weight (after 20 weeks).

University of Edinburg leader Prof Sir Aziz Sheikh said: “Our findings demonstrate that protection gained through COVID vaccination drops off faster for people with severe obesity than those with a normal body mass index. Using large-scale data assets such as the EAVE II Platform in Scotland have enabled us to generate important and timely insights that enable improvements to the delivery of COVID vaccine schedules in a post-pandemic UK.”

The University of Cambridge team studied people with severe obesity attending the Obesity clinic at Addenbrooke’s Hospital in Cambridge, and compared the number and function of immune cells in their blood to those of people of normal weight.

They studied people six months after their second vaccine dose and then looked at the response to a third ‘booster’ vaccine dose over time. The Cambridge researchers found that six months after a second vaccine dose, people with severe obesity had similar levels of antibodies to the COVID virus as those with a normal weight – but those antibodies were less effecctive.

The antibodies’ neutralisation capacity was reduced in 55% of individuals with severe obesity were found to have unquantifiable or undetectable ‘neutralising capacity’ compared to 12% of people with normal BMI.

“This study further emphasises that obesity alters the vaccine response and also impacts on the risk of infection,” said first author Dr Agatha van der Klaauw. “We urgently need to understand how to restore immune function and minimise these health risks.”

The researchers found that antibodies produced by people with severe obesity were less effective at neutralising the SARS-CoV-2 virus, potentially because the antibodies were not able to bind to the virus with the same strength.

When given a third (booster) dose of a COVID vaccine, neutralisation capacity was restored in both the normal weight and severely obese groups. But the researchers found that immunity again declined more rapidly in people with severe obesity, putting them at greater risk of infection with time.

Categories : Metabolic Disorders Skeletal SystemTags :

Gastric Surgery for Weight Loss Harms Adolescents’ Bone Development

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In sleeve gastrectomy (SG), about 80% of the stomach is removed to reduce obesity and its complications. It has been observed to be associated with bone loss in adolescents, prompting a prospective study published in the Journal of Bone and Mineral Research, that revealed through imaging tests that SG decreases strength and bone mineral density of the lumbar spine in adolescents and young adults.

The researchers followed 29 adolescents and young adults with obesity underwent SG and 30 were without surgery over 12 months. At baseline and 12 months, participants underwent computed tomography of the lumbar spine for bone assessments and magnetic resonance imaging of the abdomen and thigh for body composition assessments.

Participants in the SG group lost an average of 34.3 kg 12 months after surgery, whereas weight was unchanged in controls. There were significant reductions in abdominal fat tissue and thigh muscle in the SG group compared with controls. Also, bone strength and bone mineral density decreased in the SG group compared with controls. Reductions in bone strength and bone mineral density were associated with reductions in body mass index, abdominal fat tissue, and muscle.

“Weight loss surgery is very effective in treating obesity and obesity-associated comorbidities in adolescents and young adults with obesity; however, it can cause loss of bone density and strength. We hope that our study raises awareness of the importance of bone health after weight loss surgery, so physicians can make sure that children eat a healthy diet with enough calcium and vitamin D and engage in weight-bearing activity to build up muscle mass, which is good for bones,” said corresponding author Miriam A. Bredella, MD, of Massachusetts General Hospital. 

Source: Wiley

Categories : Metabolic Disorders PaediatricsTags :

Autism in Children Linked to Diabetes, Dyslipidaemia

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Studies have shown that children with autism spectrum disorder (ASD) have an increased risk of obesity. In turn, obesity has been linked to increased risks for diabetes, dyslipidaemia and other cardiometabolic disorders. However, the question of whether or not there is an association between autism, cardiometabolic disorders and obesity remains largely unanswered.

To help provide an insight into the possible link between ASD and cardiometabolic diseases, Texas Tech University researchers conducted a systematic review and meta-analysis. Their findings were published in JAMA Pediatrics.

In this latest meta-analysis, the researchers evaluated 34 studies that included 276 173 participants who were diagnosed with ASD and 7 733 306 who were not. The results indicated that ASD was associated with greater risks of developing diabetes overall, including both type 1 and type 2 diabetes.

The meta-analysis also determined that autism is associated with increased risks of dyslipidaemia and heart disease, though there was no significant increased risk of hypertension and stroke associated with autism. However, meta-regression analyses revealed that children with autism were at a greater associated risk of developing diabetes and hypertension when compared with adults.

Study leader Chanaka N. Kahathuduwa, MD, PhD, said the overall results demonstrate the associated increased risk of cardiometabolic diseases in ASD patients, which should prompt clinicians to more closely monitor these patients for potential contributors, including signs of cardiometabolic disease and their complications.

“We have established the associations between autism and obesity, as well as autism and cardiometabolic disease, including diabetes and dyslipidaemia,” Kahathuduwa said. “We don’t have data to support a conclusion that autism is causing these metabolic derangements, but since we know that a child with autism is more likely to develop these metabolic complications and derangements down the road, I believe physicians should evaluate children with autism more vigilantly and maybe start screening them earlier than the usual.”

Kahathuduwa also believes the study shows that physicians should think twice before prescribing medications such as olanzapine that are well known to have metabolic adverse effects to children with autism.

“Our findings should also be an eye opener for patients with autism and parents of kids with autism to simply be mindful about the higher risk of developing obesity and metabolic complications,” Kahathuduwa added. “Then they can talk with their physicians about strategies to prevent obesity and metabolic disease.”

Kahathuduwa said the next logical step for the collaborative team would be to generate evidence that either supports or rejects causality with regard to the observed associations.

Source: Texas Tech University Health Sciences Center

Categories : Metabolic DisordersTags :

Childhood Obesity is a Risk Factor for Blood Clots in Adulthood

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Source: CC0

Being overweight in childhood and in early adulthood are discrete risk factors for blood clots (thrombi) later in life, according to a study using school health care and military service records, according to a study published in the Journal of Internal Medicine.

The association between obesity and blood clots is already established. However, to date it has been unclear how much influence a raised BMI in childhood and puberty exerts. Thrombi usually arise in the legs, often starting in a blood vessel in the calf. Swelling, pain and redness are common symptoms. Though easily treated if caught early, they can result pulmonary embolism may be life-threatening.

The present study comprises 37 672 men in Sweden, born between 1945 and 1961. It is based on information about height, weight, and BMI from the men’s records, first from school health care services (at the age of 8 years) and, second, from medical examinations on enrolment in the Armed Services (at age 20), along with register data on any blood clots up to age 62 on average.

Distinctly elevated thrombus risk

The results showed that BMI at both ages 8 and 20, independently of each other, can be linked to venous blood clots. These may occur in, for example, the leg (deep vein thrombosis, DVT) or the lung (pulmonary embolism).

In adulthood, two groups were found to be at a significantly increased risk of venous thrombi. The first was individuals who had been overweight both as children and as young adults, while the second was composed of those whose weight in childhood was normal and who became overweight only in early adulthood.

Moreover, being overweight in both childhood and young adulthood was found to raise the risk of arterial thrombi – clots resulting from constricted blood vessels with fatty deposits and inflammation. Since there were few cases of arterial blood clots in the study, however, further studies are needed to confirm these findings. All comparisons in the study were made with the control group, whose weight was normal at both 8 and 20 years of age.

Overweight in puberty an important factor

The first and corresponding author of the study is Lina Lilja, a doctoral student at Sahlgrenska Academy, University of Gothenburg, and paediatrician. At the time of the study, she worked at the Kungshöjd paediatric clinic in Gothenburg. Today, she is a senior physician in child health care in Region Västra Götaland.

“Our study shows that both overweight in childhood and overweight in young adulthood increase the risk of venous blood clots later in life. The latter, overweight when the men were young adults, proved to be a more influential factor than overweight when they were children,” Lilja notes.

The study includes data from the BMI Epidemiology Study (BEST) in Gothenburg, a population study, and from Swedish national registers.

Source: University of Gothenburg

Categories : Metabolic Disorders PaediatricsTags :

Childhood Obesity Linked to Adult Diabetes Risk

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Child obesity is linked to increased risk of developing diabetes in adulthood, both autoimmune forms of diabetes and different forms of type 2 diabetes, according to a new study in the journal Diabetologia. The risk of developing the most insulin-resistant form of diabetes is, for example, three times as high in children with obesity.

Diabetes affects ~7% of the adult population and is one of the world’s fasted growing diseases. It has traditionally been divided into two subgroups – type 1 and type 2 diabetes – but research suggests that this is a simplification.

In 2018, a Swedish study identified five subgroups of adult-onset diabetes, characterised by auto-immunity, severe insulin deficiency, serious insulin resistance, overweight and advanced age.

One way the researchers say that the relevance of these subgroups can be highlighted is to examine if the influence of known risk factors for diabetes differs between the proposed diabetes types.

“Our study is one of the first attempts to find this out,” says the study’s first author Yuxia Wei, doctoral student at Karolinska Institutet. “Childhood obesity has been linked to several chronic diseases, but has never been studied in relation to the recently proposed diabetes subgroups.”

Wanted to investigate the effect of child obesity

The purpose of the present study was therefore to see if the effect of childhood obesity differs. The researchers used a method called Mendelian randomisation, which uses genetic information to study the correlation between an environmental risk factor and disease risk while taking into account the impact of other risk factors.

Basing their analysis on genetic data from over 400 000 UK Biobank participants, the researchers compared children who considered themselves larger than other children with children who rated their weight as normal.

The results showed that overweight/obesity in childhood was linked to a 62% higher risk of autoimmune diabetes, a doubling of the risk of diabetes characterised by insulin deficiency, almost a tripling of the risk of the most insulin-resistant form of diabetes and a seven-times higher risk of the form of diabetes primarily characterised by overweight. 

“Our analyses show that children who are larger than others are more likely to develop four of the five proposed new subgroups of adult-onset diabetes,” says Wei. “In other words, obesity in childhood seems to be a risk factor in effectively all types of adult diabetes, with the exception of age-related diabetes. This underscores how important it is to prevent obesity in children since it can have lasting effects on their future health.”

The study was a collaboration among researchers at Karolinska Institutet, Bristol University (UK) and Sun Yat-Sen University (China).

Source: Karolinska Institutet

Categories : Metabolic DisordersTags :

Excess Weight is a Greater Mortality Risk than BMI Alone Suggests

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Excess weight or obesity raises mortality risk by between 22% to 91%, a significantly higher rate than previously believed, while the mortality risk of being slightly underweight has likely been overestimated, according to new research published in the journal Population Studies.

The analysis of nearly 18 000 participants counters prevailing wisdom that excess weight boosts mortality risk only in extreme cases, and it also challenges the use of body mass index (BMI) to investigate health outcomes due to its inherent biases. After accounting for those biases, it estimates that about 1 in 6 deaths in the US are related to excess weight or obesity.

“Existing studies have likely underestimated the mortality consequences of living in a country where cheap, unhealthy food has grown increasingly accessible, and sedentary lifestyles have become the norm,” said author Ryan Masters, associate professor of sociology at CU Boulder. “This study and others are beginning to expose the true toll of this public health crisis.”

Challenging the obesity paradox

While numerous studies show that heart disease, high blood pressure and diabetes (which are often associated with being overweight) elevate mortality risk, very few have shown that groups with higher BMIs have higher mortality rates.

Instead, in what some call the “obesity paradox,” most studies show a U-shaped curve: Those in the “overweight” category (BMI 25–30) surprisingly have the lowest mortality risk. Those in the “obese” category (30–35) have little or no increased risk over the so-called “healthy” category (18.5–25). And both the “underweight” (< 18.5) and extremely obese (> 35) are at increased risk of death.

“The conventional wisdom is that elevated BMI generally does not raise mortality risk until you get to very high levels, and that there are actually some survival benefits to being overweight,” said Masters, a social demographer who has spent his career studying mortality trends. “I have been suspicious of these claims.”

He noted that BMI, which doctors and scientists often use as a health measure, is based on weight and height only and doesn’t account for differences in body composition or how long a person has been overweight.

“It’s a reflection of stature at a point in time. That’s it,” said Masters, noting that Tom Cruise (at 170cm and an extremely muscular 91kg at one point), had a BMI of 31.5, famously putting him in the category of “obese.” “It isn’t fully capturing all of the nuances and different sizes and shapes the body comes in.”

Taking these nuances, Masters accessed data from the National Health and Nutrition Examination Survey (NHANES) the from 1988 to 2015, analysing 17 784 people, including 4468 deaths.

He discovered that a full 20% of the sample characterised as “healthy” weight had been in the overweight or obese category in the decade prior. When set apart, this group had a substantially worse health profile than those in the category whose weight had been stable.

Masters pointed out that a lifetime carrying excess weight can lead to illnesses that, paradoxically, lead to rapid weight loss. If BMI data is captured during this time, it can skew study results.

“I would argue that we have been artificially inflating the mortality risk in the low-BMI category by including those who had been high BMI and had just lost weight recently,” he said.

Meanwhile, 37% of those characterised as overweight and 60% of those with obese BMI had been at lower BMIs in the decade prior. Notably, those who had only recently gained weight had better health profiles.

“The health and mortality consequences of high BMI are not like a light switch,” said Masters. “There’s an expanding body of work suggesting that the consequences are duration-dependent.”

By including people who had spent most of their life at low-BMI weight in the high-BMI categories, previous studies have inadvertently made high BMI look less risky than it is, he said.

When he looked at differences in fat distribution within BMI categories, he also found that variations made a huge difference in reported health outcomes.

Exposing a public health problem

Collectively, the findings confirm that studies have been “significantly affected” by BMI-related bias.

When re-crunching the numbers without these biases, he found not a U-shape but a straight upward line, with those with low BMI (18.5–22.5) having the lowest mortality risk.

Contrary to previous research, the study found no significant mortality risk increases for the “underweight” category.

Previous studies attributed 2 to 3% of UA adult deaths to high BMI, but his study estimates an eight times higher rate.

Masters said he hopes the research will alert scientists to be “extremely cautious” when making conclusions based on BMI. But he also hopes the work will draw attention to what he sees not as a problem for individuals alone to solve but rather a public health crisis fuelled by an unhealthy or “obesogenic” environment in the US.

“For groups born in the 1970s or 1980s who have lived their whole lives in this obesogenic environment, the prospects of healthy aging into older adulthood does not look good right now,” he said. “I hope this work can influence higher-level discussions about what we as a society can do about it.”

Source: University of Colorado at Boulder