Jennifer Lovejoy, Arivale Chief Science Officer, PhD
People with obesity experience shaming, insults, and misunderstandings from family, friends, healthcare professionals, and complete strangers. It’s a sad truth compellingly and emotionally described in a massively popular recent HuffPost story by Michael Hobbes, who clearly shows the costs of the suffering experienced by people who struggle with obesity are high.
Physicians and other healthcare providers are part of the problem, as described in the HuffPost article. This is in part because of lack of adequate training. There are relatively few physicians who are board-certified in obesity medicine (for example, through the American Board of Obesity Medicine) and most medical schools don’t teach physicians how to care for patients with obesity – either in terms of the science or the human side.
As with any physical condition, it’s important to get care from a provider who is highly trained and experienced in treating that condition. No physician experienced in obesity medicine would ever tell a patient to just “lose 100 pounds.” This is a problem that needs to be addressed by healthcare training programs and patient advocates.
Where Hobbes gets off track, however, is in his very biased perspective on obesity science, including the HuffPost headline, which claims “everything you know about obesity is wrong.” The article recapitulates a lot of misconceptions about weight loss that are, unfortunately, widespread.
So, let’s look at the actual evidence related to four of the more common myths around weight loss.
Myth #1: Weight loss is almost never effective, so it’s counter-productive to try.
Because many of us have personally experienced “failure” on a diet, or known someone who has, it’s easy to believe claims that weight loss doesn’t work. Fortunately, there’s plenty of scientific evidence that shows people can be successful at both losing weight and keeping it off.
Interestingly, the same week the HuffPost article came out, the US Preventive Services Task Force released an updated Recommendation Statement regarding behavioral weight-loss programs1. This independent scientific body reviewed all current scientific literature on the effectiveness of weight-loss programs and concluded that “multicomponent behavioral interventions in adults with obesity [BMI>30] can lead to clinically significant improvements in weight status.” This is consistent with results from large randomized trials like the Diabetes Prevention Program (DPP)2 and LOOKAhead3, which both found that behavioral weight-loss programs produced significant and sustained weight loss and, in DPP, reduced the incidence of type 2 diabetes. Population-based studies like the National Weight Control Registry (NWCR)4 – a voluntary registry, not a clinical trial – also provide good evidence that people can succeed at weight loss. The average participant in the NWCR has lost an average of over 60 pounds and kept the weight off for five years through lifestyle changes.
It’s important to understand the accepted definition of “success” when it comes to weight loss. Modest weight loss – 5 to 10 percent of initial weight – can have significant health and quality of life benefits. In other words, if someone’s starting weight is 250 pounds, they would be aiming for a weight loss of 15 to 25 pounds to achieve the health benefits of weight loss. Nobody legitimate is claiming people who are 100 pounds or more overweight can become “thin” or even necessarily lose most of their excess weight (at least not without bariatric surgery). But, nearly everyone can lose 5 percent of their weight and – when combined with healthy habits and a good mindset – improve both their health and quality of life.
Furthermore, even when some weight is regained after the initial loss, health benefits persist. This was clearly shown in the DPP study, where early weight loss – even if regained – significantly reduced rates of type 2 diabetes onset for up to 15 years2. And, a similar study in China with a 23-year follow up found diabetes, heart disease mortality, and all-cause mortality were reduced for people in the behavioral weight-loss group compared to the control group, even if weight was regained5.
Myth #2: Excess weight isn’t necessarily bad for your health.
This myth is a bit harder to understand since there are a plethora of studies showing the negative impacts of high body weight on things like heart disease, hypertension, type 2 diabetes, gallstones, osteoarthritis, and cancer6-9.
The point that often gets brought up, including by Hobbes in HuffPost, is “metabolically healthy obesity.” Hobbes is not incorrect in saying there have been studies that have shown up to one-third of people with obesity may be metabolically healthy, which means having normal blood pressure, blood sugar, and cholesterol. And, of course, there are thin people who are metabolically unhealthy.
However, research has pretty thoroughly busted the myth of the metabolically healthy obese (MHO). For example, in a 2013 meta-analysis, individuals initially defined as MHO had increased risk for cardiovascular disease and cardiovascular events over time compared to metabolically healthy normal-weight (MHNW) individuals10. Similarly, in a 2014 meta-analysis, MHO was significantly associated with all-cause mortality, cardiovascular disease mortality, incident cardiovascular disease, and subclinical cardiovascular disease markers compared to MHNW11. Finally, in the 520,000-person EPIC-CVD study, irrespective of metabolic health, overweight and obese adults had increased cardiovascular disease risk, which the authors concluded challenges the concept of MHO12.
Importantly, even if an individual is an exception and maintains good cardiometabolic health, there are other day-to-day consequences of obesity that shouldn’t be ignored by anyone wanting to live a joyful life. For example, knee and ankle pain, fatigue, poor sleep, and other issues commonly reported by heavier people can significantly reduce quality of life. Modest weight loss and lifestyle changes can address many of these issues along with the potential cardiometabolic risk.
Myth #3: Weight cycling is harmful, so it’s better to stay at a consistent high weight.
There’s a kernel of truth to the idea that weight loss has an impact on metabolism: your metabolic rate (the amount of calories you burn per day) does drop when you lose weight, largely because you have less muscle mass and smaller body size. This is one reason why you have to eat less and exercise more after you lose weight in order to keep the weight off.
And, early studies – mostly in lab animals – did suggest that weight cycling, or “yo-yo dieting,” has an adverse effect on body composition, metabolic rate, and some health markers. However, as long ago as 1995, a literature review concluded “the majority of studies in humans do not support the hypothesis that weight cycling influences amount or velocity of subsequent weight loss”13. Specifically, the researchers did not find good evidence to support that weight cycling permanently altered body composition, reduced metabolic rate, or adversely impacted cardiovascular risk factors. A dramatic example of how even extreme diets don’t impair future ability to lose weight was noted in a 2007 study14. Men and women who had lost large amounts of weight (50 to 60 pounds) on a very-low-calorie liquid diet program had similar rates of weight loss per week during second and even third experiences on the same diet program.
Of course, yo-yo dieting is undeniably frustrating and disheartening even if it isn’t causing metabolic harm. Fortunately, there’s been a major focus in research over the last 10 to 15 years to better understand what it takes to keep the weight off once someone has lost it. Evidence-based programs for weight-loss maintenance are the key to avoid yo-yo dieting and the frustrations of seeing all the hard work of weight loss being undone. The US Preventive Services Task Force’s recent guideline additionally concludes that evidence-based behavioral weight-maintenance programs are supported by science.
Myth #4: Dieting leads to eating disorders and/or causes psychological distress.
As clearly described by Hobbes in HuffPost, the extreme behaviors some people engage in to lose weight – starvation diets, purging, excessive exercising – are clearly psychologically distressing and can reflect a nascent (or not so nascent) eating disorder. These approaches are not ones that any credible provider would recommend to someone trying to lose weight.
Fortunately, scientific research shows that evidence-based behavioral weight-loss programs do not cause psychological distress or increase risk of eating disorders. In fact, it’s quite the opposite. In a 2017 systematic review, quality of life, depression, anxiety, and psychosocial function all improved with weight loss15. The researchers state that evidence shows “professionally administered weight loss programs – as opposed to non-recommended unhealthy eating behaviors – do not increase risk or symptoms of eating disorders.”
A very comprehensive study looked at the effect of two different types of weight loss diets – a standard recommended 1200 to 1500-calorie whole-foods diet versus a more extreme 1,000-calorie liquid meal-replacement diet – compared to a “non-dieting” program to see if either increased risk of binge eating or other disordered eating16. The researchers found that neither diet compared to the non-diet control increased binging or disordered eating and, in fact, both dieting conditions were actually associated with greater reductions in depression than the non-dieting program.
The Hobbes article in HuffPost highlights how prevalent and terrible weight stigma and “fat shaming” are. Stories like this should be a wakeup call for the need to change the way people with obesity are treated in our society. Organizations like the University of Connecticut Rudd Center for Food Policy and Obesity and the Obesity Action Coalition perform key research and provide anti-stigma messaging, but clearly more work is needed.
But, in buying into some of the myths promulgated by the “anti-dieting movement” about the science of obesity, Hobbes has thrown the baby out with the bathwater. The reality is we do have ways to support people in healthy weight loss and lifestyle change – both from evidence-based behavioral programs and effective weight loss drugs. These approaches, supported by lifestyle coaching that focuses on the whole person and not just the number on the scale, could provide the means to transform some of the nightmarish stories shared in the article.
We have other examples of diseases that are stigmatized (such as mental health disorders), yet no one is suggesting that people who suffer from these conditions be denied effective treatments. People trying to quit tobacco make an average of nine attempts to quit before they succeed, which is frustrating and disheartening – but we don’t tell them to stop trying to break this addiction. So why do we believe that people who are suffering from obesity should forget about treatment and just “live with it?” Is our reluctance to medically, politically, and culturally embrace and promote effective weight-loss treatments and offer comprehensive insurance reimbursement for them simply another reflection of obesity stigma?
- US Preventive Services Task Force. Behavioral Weight Loss Interventions to Prevent Obesity-Related Morbidity and Mortality in Adults US Preventive Services Task Force Recommendation Statement JAMA. 2018;320(11):1163-1171. https://jamanetwork.com/journals/jama/fullarticle/2702878
- Diabetes Prevention Program Research Group, Knowler WC, et al. 10-year follow-up of diabetes incidence and weight loss in the Diabetes Prevention Program Outcomes Study. 2009 Nov 14;374(9702):1677-86. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3135022/
- Look AHEAD Research Group. Eight-year weight losses with an intensive lifestyle intervention: the look AHEAD study. Obesity (Silver Spring).2014 Jan;22(1):5-13. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3904491/
- Li G, Zhang P, Wang J et al. Cardiovascular mortality, all-cause mortality, and diabetes incidence after lifestyle intervention for people with impaired glucose tolerance in the Da Qing Diabetes Prevention Study: a 23-year follow-up study. Lancet Diabetes Endocrinol. 2014 Jun;2(6):474-80
- Jensen MD, Ryan DH, Apovian CM et al. 2013 AHA/ACC/TOS guideline for the management of overweight and obesity in adults.
- Nyamdorj R, Pitkäniemi J, Tuomilehto J, et al. Ethnic comparison of the association of undiagnosed diabetes with obesity. Int J Obes (Lond).2010 Feb;34(2):332-9.
- Klein S, Wadden T, Sugarman HG. AGA technical review on obesity. Gastroenterology 2002;123: 882.
- Prevalence of Doctor-Diagnosed Arthritis and Arthritis-Attributable Activity Limitation — United States, 2007—2009. MMWR October 8, 2010; 59(39): 1261-1265
- Kramer CK, Zinman B, Retnakaran R. Are metabolically healthy overweight and obesity benign conditions?: A systematic review and meta-analysis. Ann Intern Med. 2013 Dec 3;159(11):758-69.
- Roberson LL, Aneni EC, Maziak W, Agatston A, et al. Beyond BMI: The “Metabolically healthy obese” phenotype & its association with clinical/subclinical cardiovascular disease and all-cause mortality — a systematic review. BMC Public Health. 2014 Jan 8;14:14.
- Lee H1, Choi EK2, Lee SH3, Han KD4. Atrial fibrillation risk in metabolically healthy obesity: A nationwide population-based study. Int J Cardiol.2017 Aug 1;240:221-227.
- Muls E1, Kempen K, Vansant G, Saris W. Is weight cycling detrimental to health? A review of the literature in humans. Int J Obes Relat Metab Disord. 1995 Sep;19 Suppl 3:S46-50.
- Li Z, Hong K, Wong E, Maxwell M, Heber D. Weight cycling in a very low-calorie diet programme has no effect on weight loss velocity, blood pressure and serum lipid profile. Diabetes Obes Metab. 2007 May;9(3):379-85.
- T Peckmezian and P Hay. A systematic review and narrative synthesis of interventions for uncomplicated obesity: weight loss, well-being and impact on eating disorders.
- Wadden TA, Foster GD, Sarwer DB, et al. Dieting and the development of eating disorders in obese women: results of a randomized controlled trial. Am J Clin Nutr 2004;80:560–8
[Arivale Hot Topics address health stories currently in the news. The Arivale Clinical Team’s commentary on these news articles is not a review of the scientific evidence, nor an endorsement of a specific study, and is not meant as official medical opinion.]