Intermittent Fasting Eased PCOS Hirsutism, Not More Than Dieting: What the Research Shows

Intermittent Fasting Eased PCOS Hirsutism, Not More Than Dieting: What the Research Shows

A 2024 trial in Iran tested intermittent fasting on 90 women with PCOS, a hormone condition that can cause extra hair growth. Women who ate within a 10-hour window lost about 2 to 3 kilograms over 8 weeks, and their hirsutism scores improved - but no more than women on a standard reduced-calorie diet.

Medical disclaimer: This article summarises published research for informational purposes only. It is not medical advice and is not a substitute for guidance from a qualified health professional. Always consult your doctor before starting any fasting protocol, especially if you have an existing health condition or take medication.

The Short Version

• What they tested: Eating only within a 10-hour window each day, with or without a probiotic pill, versus a standard calorie-cut diet, in women with PCOS.
• Who did it: Sepide Talebi at Tehran University of Medical Sciences, published in Diabetes, Obesity and Metabolism in 2024.
• How many people: 90 women, all of them women, average age 30, all carrying extra weight.
• How long: 8 weeks.
• What happened: Hirsutism (extra body hair) and acne scores improved in every group, but fasting did not beat the standard diet.
• Read the study yourself: Diabetes, Obesity and Metabolism 2024 →

What They Wanted to Find Out

Many women with PCOS deal with extra facial or body hair, called hirsutism. Researchers wanted to know if eating only in an early window each day could help. They also tested adding a probiotic pill to see if gut bacteria mattered. The comparison was a standard diet where people simply cut calories at three meals a day.

If you want more background on PCOS and fasting, see how time-restricted eating affected ovulation in PCOS and how fasting changed menstrual regularity.

Who Was in the Study

Who they were: All 90 participants were women with PCOS. Their average age was 30. Their average weight was about 81 kilograms, which put most of them in the obese range.

What the fasting actually looked like: The fasting groups ate all their food within a 10-hour window early in the day. That left 14 hours without food each day. Water was allowed during the fasting hours. This lasted for 8 weeks.

What Happened

All three groups lost weight and saw less hirsutism, but fasting did not outperform standard dieting.

• Hirsutism scores dropped in all three groups, not just the fasting groups.
• Acne scores also improved across every group.
• Body mass index (a weight-to-height number) fell in all three groups.
• Markers of heart and blood vessel risk improved no matter which plan was used.
• Adding a probiotic to the fasting plan gave no extra hormone or heart benefit.

What Did Not Change

• Menstrual cycle patterns looked similar between the fasting groups and the diet-only group.
• Ovary-related hormone levels moved about the same in all three groups.
• Muscle mass: Not stated in the abstract.

What the Researchers Said

The researchers said eating within a 10-hour window, with or without a probiotic, worked about as well as a standard reduced-calorie diet. It did not work better for weight, hormones, or hirsutism.

What This Means for You

• Fasting is one option, not a magic fix. It helped as much as calorie cutting, not more.
• If you have PCOS and hirsutism, weight loss itself may help, whichever method you pick.
• For women specifically: this study only looked at women with PCOS, so results may not apply to other causes of extra hair growth.
• A probiotic pill did not add extra benefit on top of the fasting plan in this trial.
• Pick the eating pattern you can stick to. All three groups lost weight and saw similar results.
• Read more on how fasting affects PCOS hormone levels and weight management with fasting in PCOS.

What This Study Could Not Tell Us

• It only had 90 people, split into three smaller groups of 30.
• Every participant was a woman, which is useful here, but the group was small.
• It ran for only 8 weeks, so it cannot say what happens after a year.
• It was done in Iran, so results may differ in other populations.
• Funding source: Not stated in the abstract.

The Study Details

Talebi, S., Shab-Bidar, S., Moini, A., Mohammadi, H., & Djafarian, K. (2024). The effects of time-restricted eating alone or in combination with probiotic supplementation in comparison with a calorie-restricted diet on endocrine and metabolic profiles in women with polycystic ovary syndrome: A randomized (people were put into groups at random) clinical trial. Diabetes, Obesity and Metabolism. PMID: 39143654

Common Questions

Does intermittent fasting reduce hirsutism in PCOS?

Hirsutism scores went down in this study, but so did scores in the standard diet group. Fasting did not beat regular calorie cutting for reducing extra hair growth.

How much weight did women lose fasting for PCOS?

Women eating in a 10-hour window lost about 2 to 3 kilograms over 8 weeks. Women on the standard diet lost a similar amount, about 2.5 kilograms.

Did adding a probiotic help with PCOS fasting?

No. The group that added a probiotic pill to their fasting plan did not do better than the group on a dummy pill.

Is fasting better than calorie counting for PCOS symptoms?

In this 8-week trial, no. Both approaches led to similar drops in weight, hirsutism, acne, and heart risk markers.

How many women were in this PCOS fasting study?

90 women took part, split into three groups of 30 each. All of them had PCOS and extra body weight.

More Research Like This

• Time-Restricted Eating Improved Insulin and Hormone Levels in Women With PCOS
• 5:2 Intermittent Fasting Improved Menstrual Regularity in 80% of Obese Women With PCOS
• Intermittent Fasting Reduces Insulin Resistance and Improves Hormone Profiles in Women with PCOS
• Time-Restricted Eating Helped Women With PCOS Lose Weight
• Time-Restricted Eating for PCOS
• Time-Restricted Eating Helped Women With PCOS Lose More Weight
• Early Time-Restricted Eating Helped Women With PCOS Most

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