Body fat plays a crucial role in maintaining overall health, and experts are warning against the trend of chasing extreme fat-loss goals. Fat has been demonized in the past, but it has numerous biological functions, including releasing hormones and regulating body temperature. According to Elif Oral, an endocrinologist and professor of medicine at the University of Michigan, "We have to love our fat. It plays such an important biological function."
There are two types of fat: dietary fat and body fat. Dietary fat is the fat consumed in food, while body fat stores excess energy. When the body consumes more calories than it needs, fat cells store the excess nutrients as lipids, causing the fat cells to expand. Body fat is an active organ that regulates the body's functions, and it is essential to have a sufficient amount of body fat to maintain good health.
Body fat serves as a storage vault, taking up nutrients when energy is abundant and releasing them when needed. This system helped ancestors survive periods of food scarcity. Additionally, fat cells produce hormones that communicate with the rest of the body about energy levels and fullness. Leptin, a hormone produced by fat cells, tells the brain that there is sufficient energy storage, allowing the body to focus on essential biological processes.
Body fat is also essential for staying warm, as white fat stores excess energy and acts as a layer of insulation. Brown and beige fat contain specialized cells that burn energy to produce heat, helping the body maintain its temperature. Having too little body fat can have severe health consequences, including disrupted organ and bodily function, and can even lead to death in extreme cases.
The health consequences of having too much fat are well-known, including an increased risk of cardiovascular disease, type 2 diabetes, and certain cancers. However, having too little body fat can also have negative effects, such as frailty and increased risk of fractures. When the body has too little fat, it responds by trying to save energy, essentially putting itself into starvation mode, which can lead to a range of health problems.
Too little body fat can also affect hormones and reproductive health. In men, extremely low body fat can lead to low testosterone levels, while in women, it can cause irregular periods or cessation of menstruation. Several studies have found that carrying extra weight in middle and older age is associated with better survival odds during critical illness, a phenomenon known as the obesity paradox.
The optimal amount of body fat varies depending on individual needs, but healthy adult men tend to have around 10-20% body fat, while healthy adult women tend to have around 20-29% body fat. Athletes typically have lower body fat percentages, with a study finding that the lowest body fat percentage in athletes was 10% for men and 16% for women.
Key points
- Experts warn against extreme fat-loss goals, citing health risks associated with too little body fat.
- Body fat plays a crucial role in maintaining overall health, including regulating body temperature and producing hormones.
- The optimal amount of body fat varies depending on individual needs, but generally falls within a specific range for healthy adults.
