What Happens To Women’s Hormones During Intermittent Fasting?

Short-term time-restricted eating showed limited effects on measured sex hormones in premenopausal and postmenopausal women.

Intermittent fasting is an eating pattern that alternates between periods of eating and fasting. One form, time-restricted eating (TRE), involves consuming food within a set number of hours each day and fasting for the remaining hours (1^✔ ✔Trusted Source
Effect of time restricted eating on sex hormone levels in premenopausal and postmenopausal women

Go to source

).
The approach can involve different eating windows, with the fasting period lasting several hours and allowing only water or energy-free beverages. For example, TRE may involve eating all meals within a six-hour window, and fasting for the remaining 18 hours of the day.

For women, however, long fasting periods can raise questions about whether changing meal timing may affect hormones. Concerns about TRE and female sex hormones have grown, particularly over whether fasting could alter estrogen and other hormones. However, human evidence on how intermittent fasting affects hormone levels in adult women remains limited.

A small analysis published in Obesity included 23 women with obesity, with 12 premenopausal and 11 postmenopausal participants.

• Who took part?
  
  23 women with obesity, including both premenopausal and postmenopausal women.
• What did they do?
  
  They followed a four- or six-hour eating window each day for eight weeks.
• How long did they fast?
  
  The fasting period lasted about 18 to 20 hours each day.
• What happened to body weight?
  
  Body weight decreased in both premenopausal and postmenopausal women.
• Which hormone changed?
  
  DHEA, a precursor to sex hormones, decreased in both groups.
• Which hormones stayed stable?
  
  Testosterone, androstenedione and SHBG remained unchanged in both groups.

Time-Restricted Eating (TRE) And Women’s Hormones

Testosterone, androstenedione and sex hormone-binding globulin (SHBG), did not change in either group. Among postmenopausal women, estradiol, estrone and progesterone also remained unchanged.

DHEA was the exception, falling in both groups. The hormone is produced mainly by the adrenal glands and ovaries and serves as a precursor for other sex hormones.

These findings do not suggest that short-term time-restricted eating automatically disrupts several major sex hormones. However, it indicates that the hormonal response was not completely unchanged.

Faiza Kalam and colleagues wrote: “These preliminary data suggest that short-term TRE, that produces mild weight loss, has little effect on sex hormone levels.”

What Intermittent Fasting Means For Women

Someone who finishes dinner early and delays the next meal until afternoon may follow a pattern similar to the one examined. In this group, that approach was not linked with broad changes in the measured sex hormones.

The findings suggest a more nuanced picture than the idea that fasting either harms or protects women’s hormones. The results point to mostly stable measured hormones alongside a fall in DHEA, while the small sample and short duration limit how widely the findings can be applied.

The analysis excluded perimenopausal women. Estradiol, estrone and progesterone were not measured in premenopausal participants because menstrual-cycle timing was unavailable.

Intermittent Fasting and Women’s Health

For everyday decisions, the findings do not justify a blanket warning against time-restricted eating. They also cannot establish that the same hormonal response will occur in every woman or over longer periods.

The authors concluded that these preliminary findings need confirmation through well-powered trials examining women of different ages.

If you are considering time-restricted eating, the available evidence can help you approach meal timing thoughtfully.

Reference:

1. Effect of time restricted eating on sex hormone levels in premenopausal and postmenopausal women – (https://pmc.ncbi.nlm.nih.gov/articles/PMC9877115/)

Source-Medindia