Intermittent fasting is becoming a very popular and effective way to lose weight, but some are concerned that following the warrior diet could negatively impact women’s reproductive hormones. A study recently published in Obesity conducted by the University of Illinois at Chicago brings new evidence to the discussion.
The Warrior diet is a version of intermittent fasting, and this dietary practice prescribes a time-restricted eating window of approximately 4 hours a day, and within that time frame, people can eat without counting calories, after which they resume following a water fast until the following day. It can also put your body into ketosis, which is a metabolic state in which your body gets its fuel from fat rather than sugar, according to to research published in Aging Research Reviews. This diet promotes exercise and undernourishment during the day as our ancestors probably would have done, then eat a large meal in the evening with no restrictions on how much or what type of food you eat within the allotted time frame.
For this study, researchers followed a group of pre- and post-menopausal women for 8 weeks who followed the Warrior Diet intermittent fasting plan, and perimenopausal women who are typically in their 40s were excluded from this study. Participants were divided into groups of a 4-hour feeding window, a 6-hour feeding window, and a control group with no dietary restrictions. The team measured the differences in hormone levels which were obtained by analyzing data from blood samples.
After 8 weeks, the the researchers found that sex-binding globulin hormone levels were unchanged, as well as testosterone and androstenedione. Sex-binding globulin hormone is a protein that carries reproductive hormones throughout the body, and androstenedione is a steroid hormone that the body uses to produce estrogen and testosterone.
However, DHEA (dehydroepiandrosterone) levels were found to be significantly lower in pre- and post-menopausal women, with levels dropping by 14%. DHEA is a commonly prescribed hormone to help improve ovarian function as well as egg quality in women. Although the drop was the most significant finding, levels remained within the normal range at the end of the 8-week study period. As a benefit of this decrease, high levels of DHEA are linked to breast cancer, a moderate decrease may be helpful in reducing the risk of cancer in women.
“This suggests that in pre-menopausal women, the minor drop in DHEA levels must be weighed against the proven fertility benefits of lower body mass,” Varady said. “The decline in DHEA levels in post-menopausal women could be of concern because menopause already causes a dramatic drop in estrogen, and DHEA is a main component of estrogen. However, a survey of participants reported no effect negative secondary associated with low estrogen after menopause, such as sexual dysfunction or skin changes.
Estradiol, estrone, and progesterone levels were also measured, but only in postmenopausal women due to the changing levels of these hormones throughout the menstrual cycles of premenopausal women. The results show that there was no change in these hormones, which are all vital pregnancy hormones, after 8 weeks.
Those in the 4- and 6-hour eating window groups experienced a weight loss of 3-4% of their baseline weight compared to the control group who experienced virtually no weight loss. Those in the food window groups also experienced a decrease in insulin resistance and oxidative stress biomarkers.
“I think it’s a great first step. We’ve watched thousands of pre- and post-menopausal women through different alternate and time-limited fasting strategies. All it does is get people to eat less. By shortening this food window, you naturally reduce calories. Much of the negative information reported about intermittent fasting comes from studies in mice or rats. We need more studies to examine the effects of fasting. intermittent on humans,” Varady said.
As with anything you read on the internet, this article should not be construed as medical advice. please talk to your doctor or primary care provider before changing your wellness routine. This article is not intended to provide a medical diagnosis, recommendation, treatment, or endorsement.
