You are overweight because you are lazy and cannot control your appetite." For a long time, people have said this, even in the medical field. Consequently, we have long advised: eat less and exercise more. This advice, which sounds reasonable, has led us to easily judge overweight individuals.

However, this statement is fundamentally incorrect. Many emerging fields of nutritional science (as emphasized in Gary Taubes' book "The Case Against Sugar" and Jason Fung's book "The Obesity Code") suggest that weight gain is not a matter of willpower or exercise, but rather related to the types of food we consume and the role of hormones like insulin in our bodies. Insulin is the body's primary chemical signal that prompts cells to absorb glucose from the bloodstream and store calories as fat. While insulin is necessary for proper bodily function, excessive insulin secretion increases fat accumulation, leading to weight gain in areas such as the abdomen, thighs, and hips. Additionally, because insulin promotes the storage of calories as fat, it can paradoxically lower energy levels and increase appetite.

Insulin is regulated not by the total amount of food we eat, but by the amount of carbohydrates in our diet. This has been identified as the biggest issue in modern diets. Consuming carbohydrate-rich foods leads to increased insulin secretion, which promotes obesity.

As the global consumption of highly refined sugars and grains has risen, so too has obesity. In fact, obesity was uncommon until the 19th century when refined sugar and flour were developed. It was not easy to introduce high-density carbohydrates into Western diets due to a mismatch between available food and people's eating habits. However, with the widespread availability of refined carbohydrates (flour, white rice, sugar), obesity began to emerge, leading to the current epidemic. A similar trend is now occurring in South Korea. Between 1998 and 2018, sugar consumption doubled. At the same time, over one-third of Koreans were found to be obese in 2018, indicating a sharp increase in obesity rates.

High insulin levels are also associated with Western diseases such as adult diabetes, hypertension, heart disease, gout, cancer, and dementia. Recently, all of these diseases have been on the rise in South Korea. Over the past 40 years, the prevalence of diabetes in the Korean population has increased from about 1% to 10%. The rate of hypertension among Korean adults rose from less than 20% in 1990 to over 30% in 2018. Cancer and heart disease are now major causes of death in South Korea.

The best way to reduce obesity and improve community health is to decrease the intake of high-density carbohydrates. This approach differs from current popular diets like the Atkins or Keto diets, which focus solely on reducing carbohydrates and emphasizing protein. By consuming less sugar, insulin levels decrease, leading to reduced fat accumulation and obesity, as well as improved cardiovascular health. This does not mean completely eliminating carbohydrate intake, but rather avoiding the worst carbohydrates, such as sugar and refined grains (brown rice is better than white rice). Unfortunately, the cheapest (and most heavily advertised and addictive) foods are often high in sugar and carbohydrates, contributing to higher obesity rates among lower-income groups.

This does not mean you have to starve yourself. Research on low-carbohydrate diets suggests maintaining a certain weight for health while keeping calorie intake steady. While intensive exercise without food may help with temporary weight loss, it is generally difficult to maintain. Additionally, restricting calories can lead to increased feelings of depression, lower energy levels, and an overall sense of misery. However, with the Keto diet, there is no need to restrict calories; only carbohydrates are limited. Protein and fat do not cause weight gain or cardiovascular issues during consumption. In fact, maintaining calorie intake is important to prevent muscle loss.

Therefore, do not attempt to diet by starving yourself and pushing yourself into a miserable life. And do not blame yourself or others for gaining weight. Instead, it is better to reduce the intake of sugar, flour, and white rice. This will also make you healthier and happier.

Paul Han, MD

President, Association of Korean American Medical Graduates (AKAM)

AKAM, the Association of Korean American Medical Graduates, is a volunteer organization based in New York and New Jersey. We are dedicated to improving the health and welfare of our community. We focus on volunteerism, education, research, and mentorship for physicians and students interested in medicine. For more information, visit www.akam.org.