Intermittent fasting, a diet that alternates between periods of dieting and periods of normal eating, may well harm certain sex hormones in women, according to a new study.
- Various studies have shown that fasting can have health benefits: weight loss, regeneration of nerves, reduction of inflammation, reduction of blood pressure… But beware, other studies sometimes question these benefits. .
- Generally, intermittent fasting consists of spreading out meals over an 8-hour period, and fasting for 16 hours.
Intermittent fasting consists of eating only during certain hours of the day and depriving yourself of food the rest of the time. Although it has a reputation for being an effective way to lose weight quickly, it could however harm female reproductive hormones. This is confirmed by a new study conducted by researchers at the University of Illinois at Chicago (USA), and published in the journal obesity.
Intermittent fasting followed by women for two months
To reach their conclusions, the team of scientists observed a group of women suffering from obesity, menopausal or not, over a period of two months during which they had to follow intermittent fasting on the method of “warrior regime”. The volunteers were thus allowed a feeding window of 4 or 6 hours per day (but unlimited in terms of calories). Thanks to blood tests, the researchers then compared their results, and in particular measured the hormone levels in women who followed intermittent fasting and in those who had no dietary restrictions.
Regarding body mass, not surprisingly, women who followed the diet lost 3 to 4% of their initial weight, while the others lost almost nothing. They also noticed a drop in their insulin resistance, which makes it easier to eliminate glucose and fat.
An impact on a hormone crucial to reproduction
But it is especially at the hormonal level that the differences were notable. The researchers thus observed that the level of dehydroepiandrosterone (DHEA), a hormone that fertility clinics prescribe to improve the function of the ovaries and the quality of the eggs, was significantly lower (-14%) in the women who carried out the fast. food than in those who ate normally, whether or not they were menopausal. Nevertheless “participants reported no side effects associated with low estrogen [dont la DHEA est un des composants principaux]such as sexual dysfunction or skin changes”, notes Professor Krista Varady, lead author of the study, in a communicated. This is why research must go further.
“I think it’s a great first step, assures the scientist. We have observed thousands of pre- and post-menopausal women through different alternate and time-limited fasting strategies. All it does is make people eat less. By shortening this food window, you naturally reduce calories.” And to conclude: “Most of the negative information that is reported about intermittent fasting comes from studies on mice or rats. We need more studies to look at the effects of fasting on humans.”
