Most middle-aged adults in America are overweight, and 35.1% are classified as obese. That means, every third person is obese.* In 1962, every 10th person was obese.[i] What happened?!
We don’t have an answer. Most scientists think it’s a combination of genetics, lifestyle factors and changes in food access (e.g. more sedentary work, more restaurant dining, more TV, daily soda and sugary drinks, and thrifty-genes). [ii] But there are also other theories including disrupted sleep, exposure to exogenous hormones and things called endocrine disruptors, changes to your gut bacteria, oppression, and sunlight exposure. There are even theories about infectious disease causing obesity.
With so many obesogenic forces at play, you would think that we would have a battery of interventions. But we don’t. For the most part, we leave it to the patients and doctors to deal with it on an individual level.
And the treatment? Eat less! Yep. Fifty years of obesity research and the resounding conclusion is that you need to take in less calories than you burn in order to lose weight.[iii] Even with bariatric surgery and medications, the end goal is to help the patient eat fewer calories. But, anyone who has dieted knows this is very hard. If people could just “eat less,” we would not have an obesity epidemic.
What makes losing weight hard? At a biological level, it’s your fat cells. They don’t like to disappear. You get a set of fat cells when you are born, and then another set when you go through puberty. By the time you are in your early twenties, you should pretty much have all the fat cells you can generate. [iv] So weight gain mostly leads to filling up those fat cells. But something in the past 50 years has changed (re: the second paragraph from the top) where more fat cells are being generated into adulthood, leading to obesity. And it’s really hard to get rid of them. Even with liposuction—the most popular cosmetic surgery in the world[v]—fat cells return!
Fat cells aren’t all bad. They do great things like release important hormones and regulate reproduction. But in obesity**, it’s as if they can’t stop sending signals, so you are constantly fighting the urge to feed yourself.
However, there is hope. A high-intensity, in-person intervention provided by a behavioral specialist, nutritionist or other trained profession with at least 14 sessions in 6 months is effective. The components of the intervention are no surprise: reduced-calorie diet, increased physical activity and strategies to trouble-shoot dieting challenges. When this isn’t possible, food-tracking seems to be effective, too. But you have less personal support. Free online apps like Lose-it and MyFitnessPal are popular.
There may be a future when we’ve figured out all the environmental causes of obesity and coordinated a really effective population-based treatment. In the meantime, we should try our very best to pack half of our plates with fresh fruits and veggies at every meal, and to exercise everyday. And if you are obese or overweight, don’t be afraid to ask your doctor or healthcare provider for help. They want to help. It’s what they are there for. Your whole health is important to them.
*The term obesity means fatness, and the most common way we measure it is by the body mass index, a.k.a. BMI. That is equal to your weight in kilograms divided by your height in meters-squared. A BMI greater than or equal to 30 is considered obese. Sometimes the BMI can be high because of a lot of muscle, but for most people it is due to fat composition.
** Obesity has been debated as to whether or not it is a disease in itself. Regardless, it can be a cause of heart problems, blood clots, diabetes, joint problems, social problems, breathing and sleeping difficulties, and cancer.
[i] Fryar CD, Carroll MD, Ogden CL. Prevalence of overweight, obesity, and extreme obesity among adults aged 20 and over: United States, 1960–1962 through 2011–2014. National Center for Health Statistics Data, Health E-Stats, July 2016. https://www.cdc.gov/nchs/data/hestat/obesity_adult_13_14/obesity_adult_13_14.htm
[ii] Williams, E.P., Mesidor, M., Winters, K. et al. Overweight and obesity: prevalence, consequences, and causes of a growing public health problem. Curr Obes Rep. 2015). 4: 363. https://doi.org/10.1007/s13679-015-0169-4
[iii] Jensen MD, Ryan DH, Apovian CM, et al. 2013 AHA/ACC/TOS guideline for the management of overweight and obesity in adults: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Obesity Society. Obesity. 2014;2:S5–39. doi: 10.1002/oby.20821.
[iv] Rosen ED, Spiegelman BM. What we talk about when we talk about fat. Cell. 2014 Jan 16;156(1-2):20-44. doi: 10.1016/j.cell.2013.12.012. Review. PubMed PMID: 24439368; PubMed Central PMCID: PMC3934003.
Angelie Singh, MD, MPH, MS