Chapter 134: Alternative Weight Loss Methods (Improper Weight Loss May Cause Infertility - Summary of the Entire Book)

Evidence collected over 15 years by American scientists Ross E. Frisch and Roger Revel suggests that women possess reproductive capacity due to a minimum amount of body fat required to maintain a normal menstrual cycle. For adult women, excessive fat loss can unknowingly lead to cessation of ovulation or manifested amenorrhea. They also found that the most significant change in body tissue during the rapid weight gain period before menarche in girls is a substantial increase in body fat. Girls who mature early and late both gained an average of 120% more body fat (from 5 kg to 11 kg), while non-fat body mass increased by only 44%.

Fat also affects male fertility. Studies on male sexual function have found that when calorie intake decreases, leading to weight loss and reduced fat tissue, libido is the first thing to decrease. As weight continues to drop, prostatic fluid decreases, reducing sperm motility and lifespan.

Therefore, too little adipose tissue can lead to hypothalamic dysfunction, severely impacting the quantity, quality, and lifespan of sex hormones. It's important to understand the concept of "obesity" correctly; excessive weight loss not only affects physical health but also reproductive capacity.

Some experts believe that there is a substance called "leptin" in the human body, and the amount of this substance and the body's sensitivity to it determine a person's weight.

Leptin, also known as the "lipolytic hormone," is, as the name suggests, used to "dissolve" body fat. First, it acts on the appetite center to reduce appetite and decrease calorie intake; second, it acts on the energy metabolism center to increase energy expenditure; and third, it also directly acts on fat, inhibiting its synthesis and accumulation.

Families with a predisposition to obesity often have genes that control leptin secretion-specifically, the obesity gene-that function differently from the general population. This means that obese individuals either have insufficient leptin secretion or their bodies are insensitive to leptin. Leptin deficiency leads to fat accumulation; while insensitivity to leptin indicates that although leptin levels may be the same as in the general population, the presence of leptin antibodies or leptin receptor defects prevents leptin from functioning properly, resulting in fat accumulation. Therefore, the amount of leptin and the body's sensitivity to it determine a person's body shape (fat or thin).

Animal experiments have confirmed that injecting obese animals with artificial leptin can lead to weight loss. This indicates that increasing leptin levels in animals with insufficient leptin secretion can promote weight loss, while increasing leptin levels in animals that are insensitive to leptin can also have a weight-loss effect.

There is reason to believe that treating human obesity with artificial leptin will become a reality in the near future.