Stored energy: the role of body fat and the risks of its deficiency

The stored energy

When we talk about fat we can refer to both dietary fat and body fat. Dietary fats are those you take in through your diet, while body fat is how the body stores excess energy. When you eat a meal, the dietary fats, carbohydrates and proteins in it are broken down into simple basic units that the body can use as an energy source. Carbohydrates turn into glucose, proteins into amino acids, and fats into fatty acids. If you consistently eat more calories than you expend, fat cells store these excess nutrients in the form of lipids, causing the cells to increase in size. Fat performs countless functions in the body, from releasing hormones to regulating body temperature, so excessive loss of it is harmful to your health. Body fat is often compared to a specialized depot that stores nutrients when energy is abundant and releases them only when needed, Mikael Ryden, professor of clinical and experimental adipose tissue research at the Karolinska Institute in Sweden, tells the BBC.

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The risks of excessive fat loss

Fat cells produce hormones that signal to the rest of the body how much energy we have available and how full we are. Among these, the most studied is leptin, explains Oral. "Leptin communicates to the brain that energy reserves are sufficient, thus allowing it to 'relax'", says the expert; this allows the organism to focus on fundamental biological processes, such as reproduction and fighting infections. In the absence of leptin, the brain begins to worry about the amount of energy available, leading to neglect of essential functions. Body fat is also critical for maintaining heat. While white fat stores excess energy, it also acts as an insulating layer; brown and beige fat, on the other hand, contain specialized cells that burn energy to produce heat, thus helping the body maintain its temperature. In recent studies, scientists have highlighted that, of course, excess fat can lead to a greater risk of cardiovascular disease, type 2 diabetes, some types of cancer and osteoarthritis, but you can run serious risks even when you have too little. “An insufficient amount of adipose tissue impairs the functioning of organs and the body,” says Jessica Maung, a researcher and postgraduate student specializing in metabolic diseases at the University of Michigan.

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