Obesity is not new. But, according to the World Health Organization, since 1990 adult obesity has more than doubled to 2.5 billion adults, and youth obesity has quadrupled with more than 160 million children and adolescents suffering with excessive fat deposits.
Historically, the earliest depiction of overweight people emerged during the Paleolithic era in figurines of overweight or obese women. The most famous being the “Venus Willendorf” from around 25,000 B.C. This limestone statuette featured a faceless woman with large belly, voluptuous breasts, and curvaceous thighs. These prehistory figurines depicted hunter-gather women with generalized obesity, central adiposity, and large waists.
So what the heck has happened over the past 30,000 years?
“The overall scarcity of food throughout early human history likely led to a belief that being overweight was a good thing,” says Dr. Hans Wolf, the founder of the Physicians Achievement Concept Course and director of WOLFPACC. “That would explain why corpulence and female chubbiness were desirable qualities as reflected in their art. But ancient physicians also documented concerns that excess weight was a likely precursor to a variety of health issues.”
A more recent study examined one hundred examples of the Paleolithic-era art forms from a sociocultural perspective and concluded these represented malnutrition and various states of gravidity. Moreover, since skinny figurines were mostly young women, it appears the impact aging had on weight was also noted. Researchers identified a body-weight spectrum in the collection of statuettes, including underweight, normal weight, overweight, and obese individuals.
Since the figurines preceded discovery of agriculture and animal husbandry by Neolithic humans, it indicates unintended fat gain appears to have preceded steady food availability. Cultural anthropologists know from changes in dental microbiota that the revolution of food abundance did not begin until around 10,000 B.C. That’s when agricultural settlements replaced hunter-gather tribes with periodic farm work, which was a more sedentary lifestyle that likely led to the earliest energy imbalances.
Hippocrates paved the way…
Typically regarded the father of medicine, Hippocrates was a physician who lived during Greece’s Classical period. He became the most famous physician in antiquity and along with the Ancient Roman physician Galen created The Theory of the Four Humors. Galen suggested imbalances in the human body could be restored by applying the opposite to the humor that needed to be fixed. During the Greco-Roman and Byzantine Eras, scientific principles further postulated that a healthy person had a balanced body that was moderate thin to moderate fat.
Physicians were basically in agreement that being overweight or obese had a negative impact on balance, thus weight management became a consideration of the time. Treatment options focused on weight loss, which included recommendations for diet, herbal medications, and changes in lifestyle. It was during the Byzantine Era that the Mediterranean diet was first shown to reduce the incidence of obesity and was considered to be a preventative eating pattern focused on consuming fish, fruits and vegetables.
Although Hippocrates was not the first physician to prescribe exercise for patients, that honor goes to Sushruta of India who encouraged daily exercise. However, the Greek philosopher and physician was the first to provide a written prescription for exercise (walking) for patients who suffered from a wasting disease known at that time as consumption. Historically, the concept of healthy dietary intake combined with routine exercise continued across many societies and laid the groundwork for what is now known as lifestyle medicine.
Causes and Consequences of Obesity
With many centuries in the rearview mirror, today’s medical student is taught that overweight and obesity result from an imbalance in energy intake (caloric intake or stored body fat) and energy expenditure (physical activity). So, what’s really changed since the ancients proclaimed, “eat less and exercise more”? For starters, care providers no longer have to use a series of figurines to compare what proved to be very accurate depictions of the common stages of weight gain.
In modern-day healthcare environments, the quickest way to determine if a person is affected by overweight or obesity is to determine the individual’s Body Mass Index (BMI), originally known as Quetelet’s Index, that estimates body fat by comparing one’s weight to one’s height. So both providers and patients can calculate a body mass index using an online BMI Calculator. A BMI below 18.5 suggests the person is underweight, 18.5 to 24.9 is considered to be normal weight, 25 to 29.9 is categorized as overweight and a BMI of 30 or greater is obesity.
Other Ways to Measure Body Fat
Unless you are a professional athlete or a highly-active individual with increased muscle mass, determining your body mass index can be accomplished using simple measures. You’ve probably heard about “pinch an inch” and it is an easy way to determine BMI using skinfold thickness. But the actual body fat test uses a skinfold caliper to pinch specific area of the body (abdomen, back of the arm, or shoulder area) to predict body fat percentage. However, similar to BMI measures is not an accurate indicator of overall body composition but a measure of relative fatness.
Waist-to-hip calculations use a measurement of circumference to help assess abdominal obesity by establishing healthy ratios separately for men and women. Basically a waist-to-hip ratio greater than 1.0 indicates a risk of chronic health problems like type 2 diabetes, heart disease and stroke. Although these simple measures are generally a good way to estimate how much body fat a person has, it does not measure body fat directly and therefore is not reliable in all cases as an indicator of current health or future risk of illness.
Additional measures for body fat percentage include hydrostatic (underwater) weighing, bio-impedance using a low electrical current, computerized tomography (CT scan), magnetic resonance imaging (MRI), and dual-energy X-ray absorptiometry (DXA scan). Since DXA scans measure both body fat percentage and body composition, it is considered to be the most accurate measurement, but is not readily available to the public. DXA scans are commonly used for bone density test or muscle mass determinations for athletic training.
The Dawn of Anti-Obesity Drugs
The earliest association between obesity and disease dates back to 15th century B.C. when treatments were mentioned for people who suffered from excess urination. Sushruta was the first physician to officially link obesity to heart problems and metabolic diseases like diabetes. Someone with excessive weight was believed to be more likely to suddenly die, and corpulence has long been described as not only a disease itself, but the harbinger of other dangerous health conditions.
Until recently, an oral weight loss medication phentermine had been the go-to-drug of choice for helping obese patients who had been unable to lose weight through diet and exercise alone. Although originally intended for short-term use to suppress appetite, the drug is currently allowed for long-term therapeutic treatments. Since it mimics an amphetamine, there is always a concern of misuse. Depending upon a patient’s personal risk factors and potential health benefits, phentermine is still being prescribed, most likely due to its affordability.
More recently, GLP-1 receptor agonists have taken the world of weight loss by storm. Although semaglutide was originally developed to treat type 2 diabetes by lowering blood glucose levels, one of the most common side-effects noted during early clinical trials was unintended weight loss. Marketed under different names, several drugs in this class of incretin mimetics are being prescribed for weight management. In addition, a novel therapeutic being studied for metabolic and endocrine disorders is VK2735, with dual GLP-1 and GIP mechanisms similar to tirzepatide.
Still Seeking Solutions for Satiety
Since overweight and obesity may have preceded a readily-available food supply, scientists are still studying the effects that malnutrition, metabolic inefficiencies and endocrine disorders play on fat gain. As well as how obesogenic environments (the collective physical, economic, policy, social and cultural factors) that promote obesity. Obesogenic environments with limited access to healthful food outlets and facilities for physical fitness are associated with obesity and increased cardiovascular risks.
Dieticians know that protein can promote weight loss because it increases satiety by triggering the release of GLP-1 (glucagon-like peptide-1), making it easier to control one’s appetite due to feeling full longer. Additionally, lean sources of protein helps maintain calorie-burning muscle mass, which facilitates fat oxidation. Other foods like high-fiber grains, healthy fats, eggs, leafy greens, nuts and seeds, and resveratrol found in red wines, grapes and berries also mimic GLP-1 neurotransmitters.
Today’s medical students can look forward to continued advancements in understanding the role that genetics and hormonal imbalances play in healthy living. So it will be interesting and highly beneficial to better understand the role that satiety plays in unintended weight gain. Maybe Hippocrates and other ancient physicians were right in recognizing that food is medicine and routine exercise is essential for sustainable weight control. So consuming the right foods and engaging in an exercise like walking may need to be prescribed much earlier in one’s life .
Photo credit pexels.com
___________________
Dr. Hans Wolf devoted decades to developing WOLFPACC’s “The Power 5” Methodology for helping medical students understand how to apply the basic sciences that they learned in medical school to the practice of medicine. If you’re ready to be the best physician you can be, contact us today to schedule a USMLE or COMLEX review program.
