Obesity Care

Effects of Characterising ‘Obesity as a Disease’ on Weight Bias

This study sought to work out the implications of categorising obesity as a disease on weight bias. A sample of 309 participants were recruited and measures of demographics, ideology, general attitudes and previous contact with people living with obesity were taken. Participants then read one of three articles as part of an experimental manipulation, one framing obesity as a disease, one framing it not as a disease and a control article on an unrelated topic. After reading, the participants were reassessed for measures including disgust, empathy, blame and weight bias.

The ‘obesity is a disease’ manipulation had a direct positive effect on the emotional response of the participants towards individuals with obesity, because of a reduction in blameworthiness and controllability. However, this was complicated due to a heightening of essentialism; by perceiving obesity as an inherent component of the individual,  the individual becomes bad because obesity is bad. This means that framing obesity as a disease which is out of the control of the individual, is not without its consequences to weight stigma.

Another interesting finding was that those participants that had a strong ‘just-world’ beliefs, defined as those that think that people get what they deserve, and thus readily attribute blame to others misfortune in order maintain that belief. This subgroup were most susceptible to a change in emotion when given the article on ‘obesity is a disease’. This suggests that prejudice reduction strategies may need to be more specific and targeted, depending on the group that one is seeking to influence.

This study highlights the nuanced approach that must be taken when trying to implement a stigma reduction programme. Characterising obesity as a disease does not straightforwardly reduce stigma. It also highlights the importance of understanding the target audience when conducting a stigma reduction programme, as a huge number of personal variables, such as political and philosophical views, affects how they react to the information, and these must be taken into account  in order to make the programme effective.

Weight-Related Stigma is Associated with Bodily Pain Among Females with Overweight or Obesity

Pain is a common comorbidity among individuals living with overweight or obesity, however the mechanism linking the two is not clear. This studyevaluated the relationship between perceived weight-stigma and self reported bodily pain in a sample of obese/overweight adult women through questionnaires designed to measure both.

They found that perceived stigma and internalised stigma were associated with physical pain. Weight-related stigma among women with overweight or obesity appears to be associated with greater experience of physical pain. There is evidence that social and physical pain may be processed through similar physiological mechanisms and that weight stigma may potentiate the experience of pain through those neuroanatomical pathways.

What is known so far is that social factors, such as major life stressors (eg. trauma) and chronic exposure to socially painful situations (eg. conflict or isolation), increase vulnerability to pain by causing  heightened sensitivity to painful stimuli. Alongside this, permanent social stress is also thought to affect an individual’s resilience to pain. If they lack meaningful social ties and are in a negative emotional state then they’re less capable of sharing the burden and thus coping with pain.

Although more research needs to be done to evaluate the mechanisms behind this process, these findings suggest that clinicians should be considering stigma internalisation when treating obese patients suffering from chronic bodily pain.

Impact of Early‐Life Weight on Cognitive Abilities in Children

A developing child’s mind is highly sensitive to environmental factors and it is now well known that overweight and obesity has a significant impact on the metabolic and endocrine profile of  an individual. This new study, published in Obesity, sets sets out to try and determine if childhood obesity has any effect on cognitive ability, guided by the hypothesis that the production of adipocytokines and inflammatory molecules may adversely affect neurodevelopment.

The study included 233 children, who underwent measurements of weight and height to formulate a WHZ score, in the first two years of life. Then through ages 5 to 8 years, the children underwent a comprehensive assessment of cognitive abilities, including attention, impulsivity, working memory and reference memory.

Their findings suggest that early high WHZ, may be inversely associated with full scale IQ, perceptual reasoning index and working memory index, after adjusting for potential confounders. It also found slower reaction time and lower continuous performance test scores. The other cognitive tests conducted did not find an association with early-life WHZ.

The strength of this study is that it used prospective data which enabled them to investigate weight status in the first 2 years of life, which are critical to brain development. This allowed for better understanding of the direction of the association. Furthermore the cognitive tests were repeatedly administered by professionals, and encompassed a comprehensive array of cognitive abilities, which previous studies had not done. FInally they also accounted for covariates, such as socioeconomic status, perinatal factors and maternal IQ.

From this they are able to conclude that early-life obesity seems to affect full scale IQ, perceptual reasoning and working memory scores (boys only), as well as increasing reaction times among school aged children. More research needs to be conducted to confirm these findings, and the authors suggest also measuring school performance, ADHD diagnosis, learning disabilities or special education service use.

A Study of Weight Stigma Experienced by Mature Patients with Obesity in Disadvantaged Areas of Australia

There is a growing recognition of the impact stigma has on the health seeking behaviors and self-efficacy of obese patients.This study,set out to identify predictors of perceived weight stigma among patients attending general practices in socioeconomically disadvantaged urban areas of Australia. The predictors selected were socioeconomic factors (age, sex, language spoken at home, education level, and occupation), obesity category and healthy literacy.

To measure stigma, they used two items from the The Impact of Weight on Quality-of-Life-Lite Measurethat focussed on direct experiences of stigma, such as being ridiculed or teased. From it’s sample size of 120, this study found that one-third of the sample had experienced direct forms of weight discrimination in the week prior to being interviewed. The strongest predictors of stigma were higher obesity category, coming from a home where english is not the first language, being unemployed, and scoring low on the health literacy questionnaire on questions relating to ability to engage healthcare providers.

Interestingly, this study found no significant correlation between age, sex or race, which have been well documented as predictors of stigma in the USA. This study highlights the importance of tackling stigma in the healthcare setting, as well as the need for equipping these patients with coping mechanisms. In patients that are already at a disadvantage with regards to receiving healthcare, it is imperative that programmes are implemented to tackle stigma, as it can compound the disadvantaged position of these individuals, and further act as a barrier to them seeking medical help.

Association between obesity with disease-free survival and overall survival in triple-negative breast cancer: A meta-analysis

In a systematic review, published in Medicine, the authors sought to investigate whether obesity conveyed a benefit to disease-free survival (DFS) and overall survival (OS) in patients with triple-negative breast cancer. Breast cancer is a complex condition with many different subtypes, which each behave in different ways. Triple negative breast cancer means that there is not enough expression of three receptors, ER, PR and HER-2. It is a rare and often aggressive form of breast cancer, characterised by short recurrence time and greater chance of metastasis via the bloodstream.

The effect of obesity on cancer survival is still contested, and it varies between each type of cancer. The rationale behind it increasing survival is that by having a greater body mass, an obese patient is better able to survive the wasting effects of cancer and its treatment. Conversely, it is argued that many endocrine, metabolic and inflammatory complications that result from a persistent obese state, predispose these patients to cancer and limits there survival ability. This review included data from 9 studies for DFS meta-analysis (4,412 patients) and 8 studies for OS meta-analysis (4,392 patients). It found a number of controversial studies, which suggested obesity conveyed a very significant survival advantage, and others, which concluded that the opposite was true. The result of their analysis is that there was no statistically significant difference between the DFS and OS rates of obese patients compared to normal weight patients in triple negative breast cancer.

Effects of Physical Activity and Sedentary Behaviour on Brain Response to High‐Calorie Food Cues in Young Adults

Physical activity is known to be an effective method of weight management, due to increased burning of calories. However, this study published in Obesity, found that beyond the calorific effect, there is also a physiological change in the brain in areas associated with reward.

For this study, 22 lean and 18 obese people were selected and their activity levels assessed. Looking at levels of moderate to vigorous physical activity (MVPA), and levels of sedentary behaviour (SB). Next, they ingested some glucose and underwent an fMRI brain scan, and while in the scanner, they were shown images of high-calorie foods, alongside inanimate objects. The researchers looked at 10 regions of the brain known to be responsive to visual food cues. What they found is that those who engaged in MVPA had lower responses to the food cues, and those who engaged in SB, had higher responses. This was true of the healthy weight individuals, and particularly true amongst the obese participants.

The potential mechanism through which physical activity suppresses responses to food cues is still unclear, however what is clear is that reducing SB and increasing MVPA can have positive effects on regions of the brain associated with food perception. Future studies on the underlying mediators of the effects of physical activity on the brain’s response to unhealthy food cues, may provide an interesting new approach to treating obesity.  

Identification of Children’s BMI Trajectories and Prediction from Weight Gain in Infancy

The causes of childhood obesity are not always clear; however, the risk that it poses to adult health outcomes, such as cardiovascular health and premature death, mean that an understanding of common patterns and predictors in infancy are essential. This paper published in Obesity, used data on birthweight and BMI from 1,364 children of ages 24 months to 13 years, to see which patterns are associated with higher risk of becoming overweight or obese.

They found that risk of membership of a high-BMI trajectory could be predicted from as early as 15 months old. Birth weight for gestational age and percent weight increase in the first 15 months are the strongest predictors for following a high-rising trajectory of weight change across childhood. Therefore, high-birth weight should trigger parents and physicians to ensure healthy nutrition. More importantly than that, rapid weight gain in the first 15 months was found to be strongly correlated to high-BMI in later life, meaning that close monitoring of weight-gain in early life, along with intervention, could be a new way of preventing childhood obesity.

Metabolically Healthy Obesity, Transition to Metabolic Syndrome, and Cardiovascular Risk

This study, published in the Journal of the American College of Cardiology, used data from 6,089 participants of the MESA study to see how having a healthy metabolic profile despite obesity, affects your risk of cardiovascular disease.

The debate over the risk of cardiovascular disease (CVD) associated with the three groups, metabolically healthy normal (MHN), metabolically healthy obese (MHO) and metabolically unhealthy obese (MUO), stems from the apparent contradiction that an individual can be obese (BMI>30 Kg/m2) and yet be free of metabolic syndrome (MetS). This study found that for the vast majority of people, MHO was a transition state towards MUO, and that there was a dosing effect associated with obesity. With the risk of developing MetS being relative to cumulative obesity exposure. They found that almost one-half of those with MHO at baseline, developed MetS during follow-up. Higher MetS duration was also significantly associated with CVD, supporting the theory that risk from obesity is cumulative.

Very few individuals can stay metabolically healthy when continuously exposed to obesity, and the transition to MetS represents a massive increase in risk of CVD. Clinicians should see MHO as an opportunity for early intervention, to prevent later disease, rather than waiting for an unhealthy metabolic profile to develop, by which point, risk has already massively gone up.

Ectopic fat obesity presents the greatest risk for incident type 2 diabetes: a population-based longitudinal study

Obesity is usually evaluated based on BMI, however more and more research is showing that the distribution of fat within the body is important in determining the harmful metabolic effects of obesity.

In this historical cohort study, conducted in Japan, and published in the international journal of obesity, the authors set out to determine the relationship between different phenotypes of obesity and the onset of type 2 diabetes. The authors used three phenotypes, obesity, visceral fat obesity and ectopic fat obesity; defined as body mass index >25 Kg/m2, waist circumference >90cm in men or >80cm in women, and having fatty liver diagnosed by abdominal ultrasound. Ectopic fat is defined as extra adipose tissue in locations not originally associated with adipose tissue storage. The study included 15,464 participants, who were divided into 8 groups, depending on the absence or presence of each phenotype.

They found that obesity and visceral fat alone had very little effect on the risk of incident type 2 diabetes and that the presence of ectopic fat obesity presented the greatest risk of developing type 2 diabetes. Several studies have shown before that increased adiposity in the liver leads to disrupted metabolic function, including glucose control, however this is the first study to directly compare phenotypes and assess risk. Although there were limitations to this study, the data suggests that body composition analysis should be considered when assessing a patient’s risk of obesity related disease.

Famine Exposure During Early Life May Lead to an Increased BMI in Adulthood

It has been previously reported in epidemiologic studies that famine exposure during early life is associated with overweight or obesity in adulthood. In this systematic review and meta-analysis of 20 studies, this paper set out to determine whether exposure to famine in early-life had any association with overweight or obesity in later life.

This study was conducted according to the Cochrane methodology, and included research from a variety of different famines across the world with considerations for gender and age. It found that there was a significant correlation between early life exposure to famine and being overweight in later life, and that this association was stronger in females, individuals less than 50 years of age and individuals who experienced foetal exposure.

The mechanisms for this phenomenon are still not clear, however the author goes on to discuss the different systems that the famine could affect, including a formatting of the HPA neuroendocrine access that controls energy intake and expenditure, epigenetic changes sustained during famine causing behavioural differences, as well as psychological damage to the individual, which will affect their behaviour and attitude towards food.

Cardiorespiratory fitness as a Determinant Factor for the 30% of Obese Individuals That are Metabolically Healthy

Previous studies have shown that individuals can be obese and metabolically healthy, or of normal weight with an unhealthy metabolic profile. The metabolically healthy obese (MHO) phenotype currently represents 30% of obese individuals. However, major studies have so far failed to consider the possible impact of cardiorespiratory fitness on metabolic health.

MHO individuals are characterised by having low abdominal adiposity, low inflammation level and low risk of developing metabolic comorbidity. This study hypothesised that cardiorespiratory fitness, is a determinant factor for the MHO phenotype. It aimed to investigate the associations between fitness, abdominal adiposity and low-grade inflammation within different BMI categories. Data from 10,976 individuals on waist circumference (a surrogate measurement for abdominal adiposity), cardiorespiratory fitness and C-reactive protein levels (a measure of low-grade inflammation) were analysed.

In both men and women, this study found a strong inverse association between fitness and waist circumference adjusted for age, education, smoking, alcohol and BMI. It also found that fitness reduced levels of inflammation regardless of BMI. Furthermore, a positive association between waist circumference and C-reactive protein, in both men and women in all BMI categories. This study demonstrates that there is a considerable difference in the values for abdominal adiposity, fitness and low-grade inflammation in people with the same BMI. Therefore, in order for clinicians to obtain a more accurate identification of individuals who are healthy despite obesity and individuals who are at metabolic risk despite the normal weight, additional measurements of waist circumference, CRP and fitness should be taken in to account.

Rethinking public mental health: learning from obesity

This commentary piece written in the Lancet Psychiatary, reviews Stanley J Ulijaszek’s new book, Models of Obesity. It argues that the field of mental health could learn a lot from the challenges of obesity and the approaches used to tackle it. It first argues that the obesity debate has been reframed in a way that presents it as a chronic relapsing-remitting condition. This has shifted the approach to the treatment of obesity and would be a useful if implemented in mental health.

Next, it highlights the standard unit of measurement that exists in obesity; BMI. Despite its faults, this practice has meant that it’s far easier to make sense of population obesity through epidemiological studies. Mental health researchers often use confused terminology, meaning that it is difficult to perform population studies and so to grasp the scale and nature of the issue.

Third, the field of obesity considers the complex systems that create public health problems better than that of mental health. This means that considerations for environmental factors and psychopathogenic factors are much better integrated into obesity care than in mental health.

Fourth, there is a polyrational approach in obesity that frames obesity public health in a field of competing interests and behaviours, such as between corporations and governments. This means that there is a better understanding of the rationalities and their relationship to each other.

Finally, “viable clumsy solutions” are used to address obesity; these are “a combination of single rational policies towards a particular problem”. This follows from the polyrational approach of understanding obesogenic environments. It involves bringing individual stakeholders together to find solutions, which combine to advise policy.