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Of Physical Activity, Fat, and Pharmaceuticals

Obesity is a modern behavioral problem that calls for radical lifestyle changes.

A new wave of fashionable weight-loss drugs is sweeping the world of celebrities. This may be one more example of fast pharmacological remedies for behavioral problems that accrue to modern lifestyles.

How one approaches remedies for being overweight is largely determined by time frame. Physicians coping with life-threatening obesity-related conditions want fast solutions if they are to prolong a patient's life. Similarly, celebrities who are constantly in the public eye need instant results from weight-control measures to remain popular. Fast-acting appetite-suppressing drugs are attractive options and potential side-effects are downplayed. Some of the new drugs (e. g., Wegovy) are considered safe and may produce weight loss of up to 20 percent.

Considered from an individual perspective, the key to treating obesity is prevention. Being overweight generally begins in childhood and is associated with the sedentary lifestyle of many contemporary families. This phenomenon is placed in sharp relief by considering changes in obesity over the course of several generations.

The History of Obesity

The history of obesity is noted by its general absence prior to the 20th century. Among subsistence hunter-gatherers, the general population was lean and well-toned. These qualities were not due to a scarcity of food. Anthropologists found that hunter-gatherers actually consumed a great deal more calories than urban people (1). This level of nutrition was needed to support their physically active lifestyles.

Even when our ancestors switched to farming, there was no evidence of an emergence of obesity. A farming lifestyle generally required more work than hunting and gathering. Farmers had higher fertility than hunter-gatherers, implying that women had greater fat stores that allowed them to sustain more pregnancies in a lifetime. Even so, there was no morbid obesity for either gender because subsistence farming necessitated a high level of physical activity. This point was confirmed by the case of the Pima Native Americans of Arizona who were identified as having unusually high levels of obesity. Their relatives in Mexico, who continued to work as subsistence farmers, had virtually no obesity.

When obesity first manifested itself in human societies, it emerged in urban societies where there was a strict class system. In such societies, girth signaled wealth so that fatness was perceived as an index of social success. Those at the bottom of the social ladder were forced to work hard and struggled to find enough to eat. The elite refrained from physical work and consumed rich foods that permitted them to put on weight.

Modern Lifestyle Syndrome

All of this makes it clear that contemporary obesity is the product of unhealthy modern lifestyles. Like the elites of old, we put in too little physical effort and consume too many high-calorie foods to maintain a healthy body weight.

Expanding waistlines bring a huge increase in obesity-related diseases. Secondary diabetes for example, is affecting more people at ever-younger ages. Obesity is also associated with numerous metabolic diseases, including heart disease, kidney diseases, and liver disease. This “metabolic syndrome” is so threatening to general health that it is expected to reduce the life expectancy of younger generations compared to their parents.

While medical treatments are essential for the morbidly obese, the root cause of these problems is generally behavioral rather than medical. It is easy to apply drug treatments after these problems emerge but it would be preferable if they could be prevented through lifestyle interventions early in life.

Behavioral Solutions

When farmers want to fatten their animals, they restrict their movements and feed them high-calorie foods. In terms of modern lifestyles, our young people often lead inactive lifestyles are plugged into social media and consume a diet of endless high-calorie snack foods.

Behavioral solutions to obesity prevention are simple in principle if not in practice. For example, youngsters should spend more time in physical activities and less time on sedentary pursuits such as interacting with screens. Given an inactive lifestyle, consuming sugar-laden drinks and eating high-calorie snacks is the perfect method of producing obesity, according to extensive research on lab animals. So the solutions are to carefully restrict time spent on screens as well as cutting down on junk food.


1 Cordain, L., Gotshall, R. W., Eaton, S. B., & Eaton 3rd, S. B. (1998). Physical activity, energy expenditure and fitness: an evolutionary perspective. International Journal of Sports Medicine, 19(5), 328-335.

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