Medically reviewed by Alida Iacobellis, Registered Dietitian (RD), MHSc
Writing and research contributions by Alana Freitag, Olivia Kuhlmann, and Ann Le
As we covered in Part 1 of this HAES series, Health At Every Size (HAES): An Introduction to the Non-Diet Approach, the HAES approach encourages size-acceptance and respect for body diversity by promoting life enhancing physical activity, balanced eating, and a more holistic approach to health. Taking a deeper dive, here we discuss what the research says about HAES and how the non-diet approach impacts physical and mental health, and the impacts of weight bias and weight stigma on well-being.
The Research Behind HAES
HAES is a radically different approach when compared to the traditional weight loss advice we have been exposed to for decades. It also challenges some really strong and widely held beliefs about what behaviours are healthy and what health looks like, so it’s understandable that you might be questioning how well the approach works and if it’s actually healthy.
Multiple studies have shown that the HAES approach is associated with improvements in physical and mental health, as well as healthy behaviour change including:
- decreased blood pressure and cholesterol
- improved eating, diet quality, and physical activity, and
- improved self-esteem and body image (1-5)
Instead of a traditional weight management approach involving some combination of a calorie restricted diet, limited intake of certain foods, and/or increased exercise, the interventions used in HAES research have focused on encouraging healthy eating, physical activity, self-acceptance, and overall well-being based on the 5 HAES principles (5). Following a few different formats including group counselling, and individual and group meetings, 7 studies aimed to investigate the effects of HAES on individuals’ health and wellbeing compared to individuals following a prescribed diet. Let’s dive into the research a little more…
HAES and Heart Health
To explore the effects of the HAES approach on heart health, researchers have investigated how this non-diet approach impacts blood pressure and blood cholesterol. The results of a 2018 systematic literature review (high-level evidence) showed a decrease in both blood pressure and blood cholesterol in participants following the HAES approach, indicating that participants’ heart health improved despite any significant weight loss (5). Despite popular belief, these findings suggest it’s possible to improve markers of health, specifically of the heart, without changing your body weight.
HAES and Eating Habits and Diet Quality
Studies have also shown the benefits of the HAES approach on improving individuals’ eating behaviours and diet quality (5). Studies have shown that the HAES approach helps people relearn to identify and trust their internal hunger and satiety cues and eat more intuitively (5). As a result, study participants experienced a decrease in restrained eating. Restrained eating refers to the intention to restrict food intake deliberately in order to prevent weight gain or to promote weight loss, or eating less than desired (6). With a decrease in restrained eating typically comes an increase in eating satisfaction and a decrease in disordered eating habits (5). Participants following the HAES approach also found themselves eating less processed foods and more fresh foods and healthy fats, suggesting this non-diet approach also encouraged the individuals to nourish their bodies with more whole foods (5).
HAES and Physical Activity
HAES has also been shown to promote increased levels of moderate to vigorous physical activity in those who adopt the approach (5). Participants also noticed that even after the studies were completed, they were more active and willing to include more physical activity in their daily routines (5).
HAES and Self-esteem and Body Image
When comparing HAES to traditional diets, the research tells us that a non-diet approach results in a significant improvement in body image. Participants following HAES reported less body dissatisfaction and a reduced desire for thinness, as well as improved self-esteem and quality of life (2, 5). By comparison, we know that dieting can negatively affect mental health by promoting negative self-image, body dissatisfaction, and low self-esteem (5). Interesting findings, especially considering one of the main contributors to our drive for thinness is the hope of more body confidence and fewer bad body image days. These results suggest that it is possible to improve body confidence, body image, and self-esteem without weight loss, and that the way you feel about your body and appearance is influenced more by acceptance of size diversity and body respect than by your clothing size or the number on the scale.
HAES and Depression
While many of the improvements in heart health, diet quality, and physical activity seen with the HAES approach can also be achieved with a prescribed diet and exercise regimen, the research tells a different story when it comes to mental health. When it comes to depression, it seems that both traditional dieting and a HAES approach can help lift depression, however with HAES you can expect this improvement in depression to have more lasting effects (3).
HAES Criticism: Size Acceptance vs. Obesity Promotion
Much of the criticism that the HAES approach and other movements focused on size acceptance and diversity attract, is that they promote obesity. Accepting is not the same as promoting. Accepting people of all body shapes and sizes, making sure they are provided with accommodations, and working to ensure they have equal access to resources is a matter of fair and equal treatment which in and of itself is health-promoting.
Weight Bias and Health
Before HAES, our approach to weight management was formed around the assumption that weight loss for people in larger bodies would lead to better health. Until recently, it was assumed that excessive fat stores on the body were fully to blame for the poorer health outcomes experienced by people in larger bodies. However, we are now beginning to understand more of the nuance that surrounds the relationship between body size and health, and we are learning that weight stigma may have an important role to play (7).
Weight Bias, Weight Stigma, and Weight Discrimination
Before we go any further, let’s get our terms straight.
Weight bias or “fatphobia” can be defined as the negative views and/or attitudes we hold about people living in larger bodies (8). For example: Personally thinking or assuming that an individual living in a larger body is lazy or has no self-control.
Weight stigma refers to social stereotypes and misconceptions about individuals living in larger bodies (8). For example: Seeing fat characters in shows/movies portrayed as comedic, lonely, or unlovable ie. Fat Monica from Friends.
Both weight bias and weight stigma can lead to weight discrimination, which is when our personal biases and social stereotypes translate to our actions and behaviours – that is, how we treat others living in larger bodies (8, 9). For example: Children being teased or bullied by their peers because of their weight.
Weight Bias and Stigma Beyond Obesity
Weight bias, stigma, and discrimination do not only impact people in larger bodies. Individuals who appear underweight may also experience ‘skinny-shaming’, a form of weight discrimination where thin people are criticized or made fun of for their appearance. Weight bias and weight stigma may take the form of generalizing that all thin people have eating disorders or starve themselves.
People living with obesity can have anorexia. And eating disorders aren’t the only explanation for why someone has trouble maintaining a healthy weight. Even still, some bodies are naturally smaller despite adequate nutrition and a healthy relationship with food.
The bottom line is this: you can assume nothing about someone’s health status by looking at their body size. Full stop.
The Health Effects of Weight Bias and Weight Stigma
Weight bias can have some very real and damaging health effects on those living in larger bodies who experience this type of discrimination, especially with the so-called “war on obesity” gaining momentum over the past few decades (9). Ironically, weight stigma has also been found to be a contributor to factors that are associated with obesity (10). Eating disorders, depression, anxiety, and avoidance of routine medical care are among some of the health risks observed in those who experience weight bias and stigma, all of which lead to poorer health outcomes.
Disordered Eating and Eating Disorders
Shaming people for their weight often contributes to the development of disordered eating or eating disorders. This is more likely to happen as people who experience weight stigma and discrimination turn to unhealthy behaviours such as excessive fasting, extreme dieting, and compulsive exercise after seeing little to no success from more moderate weight management approaches, and out of desperation to gain acceptance within their communities (7). To put the impact of this reality into perspective, eating disorders have the second highest mortality rate of all mental illnesses (11). By being more accepting and less judgemental of others based on their bodies, we can reduce the likelihood of them developing a serious mental illness.
Experiencing any kind of unfair treatment or discrimination is painful, and when humans feel pain we find ways to cope. Binge eating and avoidance of physical activity are common maladaptive coping mechanisms that are found at higher rates in those who have experienced weight bias (7, 12,13). All of this means that if you’re in a larger body, the things you may be doing to cope with the weight stigma you experience may be keeping you at a weight that is higher than what is biologically appropriate for you or causing you to gain further weight. It’s a viscous cycle – one that we can change the trajectory of by reducing weight bias, stigma, and discrimination.
People who experience weight bias may also avoid seeking medical care because of past negative experiences (14). When weight is pathologized, disease symptoms are often dismissed as being caused by weight and as a result, people don’t receive the proper treatment they may need. For example, when someone living in a larger body reluctantly visits their doctor for a sore throat, they may receive diet recommendations and warnings about their weight instead of help for their initial problem (15). On the flip side, thin people sometimes have their symptoms brushed off and are given a clean bill of health without a thorough assessment (13). Regardless of the direction of the weight bias, these responses from medical providers lead to very real and sometimes life threatening conditions being missed that would have otherwise been treatable or even preventable.
The Bottom Line
While the HAES movement goes against the status quo, it’s message that health can be achieved at many different sizes is supported by quality research. As we challenge how we define wellness, we come closer to creating a world that is more inclusive and one that promotes true health instead of just a narrow image of what health is supposed to look like.
If you’d like to learn more about how you can reduce weight bias check out Part 3 of this blog series, Health At Every Size (HAES): Social Justice and Redefining Healthy Weight.
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Alida Iacobellis is a Registered Dietitian with her Master’s in Health Science based in Toronto, Ontario, Canada. She is the creator of The MORE Method – the framework she uses to help her clients take their eating from disordered to intuitive and through Moderation, Optimization, Restoration and Elevation of their diet and mindset. Her coaching philosophy and approach is informed by Intuitive Eating, Health At Every Size, Cognitive Behaviour Therapy, Dialectical behaviour Therapy, and Motivational Interviewing.
 Bacon, L., & Aphramor, L. (2011). Weight Science: Evaluating the Evidence for a Paradigm Shift. Nutrition Journal, 10(1), 9. https://doi.org/10.1186/1475-2891-10-9
 Bacon, L., Keim, N. L., Van Loan, M. D., Derricote, M., Gale, B., Kazaks, A., & Stern, J. S. (2002). Evaluating a “non-diet” wellness intervention for improvement of metabolic fitness, psychological well-being and eating and activity behaviors. International Journal of Obesity and Related Disorders, 26(6), 854–865. http://dx.doi.org.ezproxy.lib.ryerson.ca/10.1038/sj.ijo.0802012
 Bacon, L., Stern, J. S., Van Loan, M. D., & Keim, N. L. (2005). Size Acceptance and Intuitive Eating Improve Health for Obese, Female Chronic Dieters. Journal of the American Dietetic Association, 105(6), 929–936. https://doi.org/10.1016/j.jada.2005.03.011
 Penney, T. L., & Kirk, S. F. (2015). The health at every Size paradigm and obesity: Missing empirical evidence may help push the reframing Obesity debate forward. American Journal of Public Health, 105(5). doi:10.2105/ajph.2015.302552
 Ulian, M. D., Aburad, L., Oliveira, M. S. da S., Poppe, A. C. M., Sabatini, F., Perez, I., Gualano, B., Benatti, F. B., Pinto, A. J., Roble, O. J., Vessoni, A., Sato, P. de M., Unsain, R. F., & Scagliusi, F. B. (2018). Effects of health at every size® interventions on health-related outcomes of people with overweight and obesity: A systematic review. Obesity Reviews, 19(12), 1659–1666. https://doi.org/10.1111/obr.12749
 Meule, A. (2016). Cultural Reflections on Restrained Eating. Frontiers in Psychology, 7. https://doi.org/10.3389/fpsyg.2016.00205
 Alberga, A. S., Russell-Mayhew, S., von Ranson, K. M., & McLaren, L. (2016). Weight bias: A call to action. Journal of Eating Disorders, 4(1), 34. https://doi.org/10.1186/s40337-016-0112-4
 Obesity Canada. (2020, June 18). Weight Bias. Obesity Canada. https://obesitycanada.ca/weight-bias/.
 Hunger, J. M., Dodd, D. R., & Smith, A. R. (2020). Weight discrimination, anticipated weight stigma, and disordered eating. Eating Behaviors, 37, 101383. doi:10.1016/j.eatbeh.2020.101383
 Puhl, R. M., Himmelstein, M. S., & Pearl, R. L. (2020). Weight stigma as a psychosocial contributor to obesity. American Psychologist, 75(2), 274–289. https://doi.org/10.1037/amp0000538
 Chesney, E., Goodwin, G. M., & Fazel, S. (2014). Risks of all-cause and suicide mortality in mental disorders: A meta-review. World Psychiatry, 13(2), 153–160. https://doi.org/10.1002/wps.20128
 Meany, G., Conceição, E., & Mitchell, J. E. (2013). Binge Eating, Binge Eating Disorder and Loss of Control Eating: Effects on Weight Outcomes after Bariatric Surgery. European Eating Disorders Review, 22(2), 87–91. https://doi.org/10.1002/erv.2273
 Lee, K. M., Hunger, J. M., & Tomiyama, A. J. (2021). Weight stigma and health behaviors: Evidence from the Eating in America Study. International Journal of Obesity. https://doi.org/10.1038/s41366-021-00814-5
 Darragh, M. (2020). The ‘health at every size’ approach to health: A critical review. Journal of HEIA, Vol. 6, No. 1. Retrieved from https://heia.com.au/wp-content/uploads/2020/09/Darragh_from-HEIA_Vol26No1.pdf
 Gaudiani, J. L. (2019). Sick enough: a guide to the medical complications of eating disorders. Routledge.