[Kim Jaeho's Life Story]<231> Eating Habits That Maintain Energy Balance

These days, as interest in health has increased, many people try hard based on their own health information to maintain optimal health, but the reality is that not many achieve their desired goals. Even if there are unavoidable reasons for not being able to properly practice healthy habits, it is unfortunate if one fails to maintain health due to inaccurate information despite earnest efforts.

Among these, many methods are known related to obesity, which is a cause of numerous diseases. However, because the nature of these methods makes it difficult to consider the diverse characteristics of individuals and they are applied uniformly, some methods may be effective for some people but pose risks of side effects rather than benefits for others. To reduce such risks, a comprehensive understanding of energy metabolism can be helpful.

From birth until the moment of death, we cannot live even a moment without energy. Unlike plants, humans cannot directly use solar energy; the energy needed for survival and activity can only be obtained through food. Among the many nutrients in food, the nutrients used as energy sources are carbohydrates, fats, and proteins, and alcohol contained in alcoholic beverages is also used as an energy source.

Among the three nutrients excluding alcohol, which is not an essential nutrient, the main energy sources are carbohydrates and fats. Protein is mainly used as a material to build the body and is used exceptionally when carbohydrates and fats are difficult to use as energy sources. It is known that during prolonged exercise, protein accounts for no more than 5% of the energy expenditure.

Basically, it is important to balance energy intake and utilization. If intake is insufficient, body weight decreases; if excessive, it leads to obesity, so adjustments should be made based on the body's condition. Regarding the ratio of carbohydrates to fats, their roles differ, so it is difficult to say that one is necessarily better. They should be appropriately combined considering their effects on the body during utilization and their characteristics in energy storage and use.

Our body stores energy in the form of carbohydrates and fats for future use. Carbohydrates are stored as glycogen, about 500g, for very short-term purposes, while most energy is stored as fat, which is a considerable amount sufficient to survive for about a month without energy supply. When the amount of stored fat greatly exceeds this, obesity occurs, causing numerous problems.

Energy utilization can be divided into three categories. Even when we do not engage in special activities and rest comfortably, energy is consumed. The amount of energy required to maintain bodily functions while resting in a fasting state under such favorable conditions is called the resting metabolic rate or basal metabolic rate. It is usually measured after an overnight fast, following about 30 minutes of rest in the morning, and accounts for about 60-70% of total energy expenditure.

Significant energy is also used for digestion of food and metabolism of nutrients. When we eat, food undergoes mechanical and chemical digestion to absorb nutrients, leftover waste is excreted, and absorbed nutrients are converted into forms needed by the body. The digestion and metabolism of fats, carbohydrates, and proteins use approximately 0-3%, 5-10%, and 20-30% of energy respectively, with about 10% of total energy used for these processes.

Additionally, physical activities including exercise consume a considerable amount of energy. Depending on individual activity levels, this usually accounts for 20-30% of total energy expenditure.

Carbohydrates and fats are used simultaneously, but their amounts vary depending on various factors. In a healthy state at rest, carbohydrates are primarily used, but during exercise, the duration and intensity greatly influence their use. The longer the exercise, the more fat is utilized. During low-intensity exercise like walking, most energy comes from fatty acids, but as exercise intensity increases, carbohydrate use rises and fatty acid consumption decreases.

The low-carbohydrate, high-fat diet that was once popular for dieting is claimed to be effective temporarily, but fundamentally, carbohydrates are the most used energy source, so it cannot be a good long-term method. For example, organs like the brain that require glucose will trigger overeating and increased food intake if carbohydrates are not consumed sufficiently, potentially leading to long-term fat gain.

Therefore, rather than excessively reducing one between carbohydrates and fats and increasing the other, it is better to reduce the consumption of bad carbohydrates (including sugars and processed or refined carbohydrates; see Life Story episode 202) while increasing the intake of good carbohydrates. For fats, reduce intake of saturated fats and trans fats (see episode 18), but ensure sufficient intake of unsaturated fats, which are abundant in most plant-based fats.

Jaeho Kim, Independent Researcher

This content was produced with the assistance of AI translation services.