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Health at every size
“”Fat activism isn’t about making people feel better about themselves. It’s about not being denied your civil rights and not dying because a doctor misdiagnoses you.
"Health at every size" (or HAES) pushes for an end to weight discrimination, unfair stigma, and toxic diet culture. Many of the movement's claims are backed by data.
In general, HAES has a positive focus: encouraging heavier people to love and take good care of their bodies, and to not be afraid to do things like swimming or working out. Research shows that exposure to the HAES movement leads to better health outcomes and even weight loss. People who don't hate their bodies may put more effort into taking care of them.
- 1 The science
- 2 Social issues
- 3 A few extremists
- 4 References
The traditional understanding of obesity has centered diet and exercise as key determinants of weight. This has lead to the common perception of obesity as being solely a product of poor self-control. However, recent scientific research, especially in the last decade, has pointed to a range of genetic, environmental, and socioeconomic factors that influence weight. These collectively suggest that obesity is more complex than previously thought, and that weight may be partially or even largely determined by factors beyond a person's control, or at least a lot more difficult to change than the "just exercise and eat right" rubric holds.
HAES seeks to advance the scientific understanding of obesity and in doing so improve the lives of fat people. The movement has several good points, but not all its claims are backed by scientific evidence. Some of this is due to lack of research. Researchers find that a HAES (or "weight-inclusive") approach is linked with better physical health, better mental health, and healthier habits overall.
Genes and environment play a notable role
Research has shown there are many genetic, epigenetic, and environmental factors that shape our bodies. It has been estimated that obesity is 40-70% the product of heritable genes. One study found that 80% of the children of two obese parents were obese, while only 14% of the children of average-weight parents were obese. Some people are evidently dealt a worse hand than others in terms of their risk of obesity, and thus it is not only unfair, but scientifically inaccurate, to pin obesity solely on poor diet and exercise.
The thrifty gene hypothesis posits that the human propensity for obesity may be a byproduct of our evolution. For early humans, the ability to store energy as fat during periods of plenty would have been advantageous, allowing them to better endure times of reduced food availability, and increasing their chances of surviving famine. However, in the modern societies with more stable food supplies, this fat-storing tendency has seemingly become detrimental. This could explain why obesity rates rose alongside the wider availability of refined grains and sugars that followed the Industrial Revolution. It might also explain why certain traditionally non-agrarian human populations, such as the Pima people of Arizona and the Cook Islanders of the Pacific, developed some of the highest rates of obesity after being introduced to a Western lifestyle.
Increased obesity rates can also arise from epigenetic factors. Famine can significantly alter how genes are expressed, and these changes may be passed on to successive generations. People in utero during the Dutch Hunger Winter of 1944-45 tended to have higher-than-average birth weights, and were also more susceptible to obesity, diabetes, and high cholesterol in later life than people born before or after the famine. They also had a higher mortality rate sixty-eight years later. At least one study also found that the grandchildren of Dutch famine victims had higher birth weights.
Other environmental factors play a role. A meta-analysis of 240 studies found a link between certain plastics (PCBs, phthalates, and BPA) and increased rates of obesity and diabetes. Another meta-analysis of 100 studies found a link between dietary exposure to antibiotics used in meat production and an increased risk of obesity, suggesting changes in the microbiome, i.e. the bacterial ecosystem of the human digestive tract, as a cause.
Diets often don't work and can be harmful
Traditional dieting is often ineffective and can be harmful in the long term. Recent scientific research has shown that dieting, especially using unhealthy means, is correlated with eating disorders, weight fluctuations, extreme dieting measures (such as laxatives), reduced self-esteem, increased susceptibility to weight gain, and other long-term health issues.
Willpower alone doesn't explain dieting failure. A meta-analysis found that diets generally do not work, and that many dieters regain more weight than they started with initially. Up to 80% of dieters regain some or all of the weight within a year. Diets can alter metabolism and hormone balance in ways that contribute to weight gain and retention. The human body has seemingly been hardwired by evolution to respond this way to apparent food scarcity (see the discussion of the thrifty gene hypothesis in the previous section). This "famine reaction" leads to a reduced resting metabolism, meaning the body burns less calories and stores more fat, and this lowered metabolic rate may persist even as weight is regained. Major weight loss can be metabolically identical to starvation. It can also trigger increased production of ghrelin, a gastric hormone tied to hunger, and decrease peptide YY and leptin, hormones associated with hunger suppression. These hormonal changes may also persist long after the initial weight loss. All this means that not only are lost pounds regained, but subsequent weight loss attempts are more difficult. People who want to stay in shape must also adhere to stricter diets and exercise more than just three decades ago due to an apparent shift in biological and environmental factors. A study found that people in 2006 had higher BMIs than people of the same age who followed an identical diet and exercise regimen in 1988.
Reduced caloric intake can increase cortisol production and psychological stress. Excessive cortisol, often known as the "stress hormone," can have several health consequences. Not only does it cause weight gain, but it is associated with depression, anxiety, and sleep problems. It can also negatively impact the cardiovascular system, and has been linked to an increased risk of heart disease.
Fad diets are especially awful for losing weight. More dangerous fad diets may even result in death. A woman in the UK died as a result of following a breatharian diet. Weight cycling, or "yo-yo dieting," increases heart disease and mortality. Some studies have found that the weight fluctuations associated with "yo-yo dieting" may have worse health outcomes than a stable (even overweight) weight.
It can be difficult to measure how strictly someone follows a diet. Dieters may under-report the number of calories that they eat and/or over-report the exercise they do. This means that they may not be following a diet as well as they think they do.
Healthy eating isn't simple for everyone
Maintaining a healthy diet is generally sound advice. However, it presumes that everyone has equal access to good, nutritious food. This isn't always true for marginalized and low-income people. Poverty is associated with an increased risk of obesity. Fresh vegetables and meat can be prohibitively expensive for the poor, leading them to opt for cheaper, unhealthier food choices. These typically include energy-dense foods like potatoes and processed meat products, which are more palatable, have a longer shelf life, and allow poor families to maintain energy intakes at a lower cost than more expensive, less-energy-dense foods. However, energy-dense foods tend to have higher fat and sugar content, and are thus more unhealthy. Nonetheless, agricultural advancements have made energy-dense foods widely available, and they now comprise 30-50% of the Western diet.
Some people live in "food deserts" with less access to affordable and nutritious food. These areas are typically poor, minority, or rural communities. They often lack supermarkets, leaving residents with less food options and leading them to rely on convenience stores and fast-food restaurants, which offer cheap, energy-dense foods.
Special dietary needs can also limit one's food options in a way that makes healthy eating more difficult. Irritable bowel syndrome sufferers may find healthy-diet staples like leafy greens aggravate their symptoms, and may thus favour starchy and low-fiber foods in an attempt to alleviate them. IBS has been linked to an increased risk of obesity by a number of studies. Autism, with its attendant sensory sensitivities and need for routine, can also cause dietary restrictions that pose challenges for healthy eating. Studies have found a link between autism and an increased risk of obesity.
Greater weight doesn't always mean poorer health
Research has shown that, medically speaking, weight does not always predict health. Healthy habits are important regardless of size. It's possible for an overweight or obese person to maintain a healthy lifestyle in this regard while someone of a lower (and thus seemingly healthier) weight maintains an unhealthy lifestyle.
Matheson et al in 2012 found significant benefits among all weight classes with people who followed four healthy behaviors: not smoking, drinking moderately, exercising regularly, and eating five or more portions of fruit and vegetables per day. Overweight and obese people saw particular reductions in mortality based on how many of these habits they practiced (although there are substantial benefits for all weight groups). In those with none of the healthy behaviors, the hazard ratio for the obese (BMI > 30) was about three times that for those classed with normal weight (BMI 18.5 to 24.9). However, in those who did all four behaviors, there was little difference in mortality between weight classes. The study notes the "lack of time spent counseling patients to adopt a healthy lifestyle" (although this may vary from area to area). There is a causal link between some unhealthy behaviors (such as not exercising and excessive drinking) and obesity, and like most studies it is a longitudinal study based on self-reporting, so it's not conclusive.
Thin people with unhealthy habits are also twice as likely to get diabetes obese people with healthy habits. Obese people may be metabolically healthy, but precisely how many are is unclear, as a literature review found numbers ranging from 6% and 75%.
"Failed" child obesity reduction programs have improved other measures of health, including athletic skills, time spent exercising, and time spent watching television. Health programs for kids may not significantly change obesity, but they can improve test scores. Seeing weight loss as the end goal of such initiatives can result in overlooking positive changes.
New approaches to healthy living
Due to the lack of positive results associated with diets, experts are now calling for a new paradigm, favoring smaller and sustainable gradual lifestyle changes over strict diets. A meta-analysis found that several practices improve body image and lead to better health: intuitive eating, Cognitive Behavioral Therapy, self-compassion, and exercise.
Weight-neutral interventions that advocate a shift away from traditional dieting show improvements in mental health and disordered eating habits, as well as positive or neutral effects on biological markers of health. Weight-neutral approaches such as Health at Every Size are a scientifically valid way to improve health, especially with regards to psychological well-being and healthy habits.
HAES advocates promote intuitive eating, which encourages people to pay attention to their own "hunger signals" rather than relying on self-imposed rules. One must eat until satisfied, and then stop. Preliminary research for intuitive eating suggests it may be effective. While intuitive eating sounds like regular behavior, it is something that chronic dieters and eating disorder survivors may need to re-learn.
Of course, intuitive eating needs to be balanced with common sense. Eating too quickly could result in people overeating because they haven't had time to realize that they're full. People with impulse control issues may overeat or binge on unhealthy processed foods. Some people with mental conditions like anxiety disorders or autism may have a hard time reading their own hunger cues. (For example, an autistic person who thinks "I should only eat when I'm hungry" could end up accidentally starving themselves if their stomach doesn't communicate hunger properly.)
The broader HAES movement tackles social issues. Many concerns of fat activists are backed by data and represent serious issues. For example, fat people face discrimination when it comes to salaries and hiring.
Negativity won't cause positive outcomes
“”I buy a package of ice cream, then eat it all. Then I have to go to the store to buy it again. For a week my family thinks there's a thing of ice cream in the fridge—but it's actually five different ones.
|—Jessica, whose fears about eating in public have led to secret binges|
Weight stigma negatively affects health. Fat shaming increases stress and leads to weight gain, and heavy people who feel discriminated against have shorter lifespans. Stigma may also cause heavy people to feel more hesitant about reaching out for help about their health.
The culture of shame around obesity clearly isn't helping heavy people get healthier. It's making their health even worse.
Shame at the doctor's office
“”Doctors repeatedly advise weight loss for fat patients while recommending CAT scans, blood work or physical therapy for other, average weight patients.
|—Joan Chrisler, PhD|
Doctors may prescribe weight loss for a number of health complaints. Failing to see past a patient's weight is dangerous, especially since it may mean that an undiagnosed medical condition (like spine issues or even cancer) gets overlooked and untreated. There's also the risk of doctors praising patients for weight loss when the patient is going way too far and developing eating disordered behavior.
Researchers have found lower quality of health care for obese patients. Physicians prefer to spend less time with obese patients, and they build less rapport with them. Nurses, too, have negative attitudes towards heavier patients.
This is particularly concerning when one considers the fact that an obese patient might need better care than average. According to the US Preventative Services Task Force, regular check-ups and extra support are ideal for patients who want to try weight loss.
“”Here I was sitting on the table coughing my lungs out while he told me that I needed to eat less and exercise more. He spent longer talking about my weight than he did about the asthma inhaler he gave me. I had never had one before and had no clue how to use it.
While doctors should be honest with their patients, there's no reason to scold them until they cry. Doctors should work together with patients to help them sort through their issues, instead of giving them a lecture without bothering to know why the patient is the way they are. "Telling someone, 'Lay off the cheeseburgers' is never going to work if you don't know what those cheeseburgers are doing for them," notes psychologist Stephanie Sogg. Making a patient feel ashamed may also cause them to avoid seeing the doctor, which means leaving health issues untreated.
An approach based in support instead of judgment could improve the doctor-patient relationship and lead to better health care.
A few extremists
However, parts of the movement veer into science denialism. Some proponents may believe that obesity is 100% genetic (it's not), that obesity is not linked to health issues (it is), or that the medical establishment is intentionally covering up the truth about weight loss.
Some of the stranger HAES advocates consider that any attempt to restrict one's calorie intake is a precursor to, or even a symptom of, anorexia. This suggests poor understanding of eating disorders. Anorexia involves a compulsive and overriding obsession with weight loss and food restriction, and it's very different from saying "I think I'll cut down on desserts."
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- Fat-Shaming by Doctors Happens Way More Often Than You Think
- Sizeism is a health hazard