Alternate-Day Fasting Improved Premenstrual Mood and Quality of Life in Overweight Women: What the Research Shows

Alternate-Day Fasting Improved Premenstrual Mood and Quality of Life in Overweight Women: What the Research Shows

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.

Study at a Glance

What This Study Looked At

Researchers wanted to know whether alternate-day modified fasting (ADMF) — eating very little on "fasting" days and normally on other days — could ease premenstrual syndrome symptoms and improve quality of life in overweight and obese women, compared with a standard daily calorie-restricted diet producing similar weight loss. PMS affects mood, physical comfort, and daily functioning in the days before menstruation, and this trial specifically tested whether the fasting pattern itself — not just the resulting weight loss — made a measurable difference. For related context on fasting and hormonal fluctuation, see carb cravings before your period: why they're normal and what to eat and the luteal phase and fasting: why the week before your period needs different rules.

Who Was Studied

Participant profile: Overweight or obese women with diagnosed premenstrual syndrome, recruited through Health Service Centers at Kashan University of Medical Sciences, Iran. Mean age was 31.76 years in the ADMF group and 32.13 years in the DCR group — a relatively young, reproductive-age sample.

How ADMF worked in this study: Participants alternated between very restricted "fasting" days and days of normal eating, over an 8-week period, while the comparison group followed a conventional daily calorie-restricted diet designed to produce comparable weight loss — isolating the effect of the fasting pattern itself rather than just calorie reduction.

What the Researchers Found

Premenstrual symptom severity (PSST subscales)

• Both mood lability and expressed anger — two of the most disruptive premenstrual symptoms for daily functioning and relationships — improved significantly more in the ADMF group than the daily-calorie-restriction control group.

Quality of life (SF-12)

• The percentage improvement in physical function, mental health, and overall SF-12 score was consistently higher in the fasting group than in the daily-calorie-restriction group, despite both groups losing comparable weight.

What This Doesn't Tell Us

• The available data does not report exact weight-loss figures for each group, so it's unclear how closely matched the two diets were in total calorie deficit — a key factor in interpreting whether the fasting pattern itself, rather than the amount of weight lost, drove the mood and quality-of-life differences.
• This trial studied premenstrual syndrome (PMS), not premenstrual dysphoric disorder (PMDD) — a more severe, clinically diagnosed condition. Findings here should not be assumed to transfer directly to PMDD, which involves more intense mood symptoms and a formal DSM-5 diagnosis.

What the Researchers Concluded

The study authors concluded that alternate-day modified fasting produced greater improvements in specific premenstrual mood symptoms — particularly anger and mood lability — and in overall health-related quality of life, compared with a standard daily calorie-restricted diet, in overweight and obese women with PMS.

What This Means If You Fast

• Fasting pattern may matter beyond weight loss. Both groups in this study lost weight through calorie reduction, yet the fasting group saw significantly better mood and quality-of-life outcomes — suggesting the alternate-day pattern itself, not just the calorie deficit, played a role.
• Anger and mood swings responded most strongly. If premenstrual irritability or mood lability are your most disruptive symptoms, this is the specific area where this study found the clearest benefit.
• This is about PMS, not PMDD. If you have a diagnosed mood disorder tied to your cycle, this study doesn't directly apply — talk to a doctor before using fasting as a symptom-management strategy for a clinical diagnosis.
• The luteal phase still deserves caution. This study didn't test aggressive or very long daily fasts — it used an alternate-day pattern. See the luteal phase and fasting for why very long fasts in the week before your period can backfire even if alternate-day patterns show promise here.
• Quality of life improved on multiple dimensions, not just the physical — the mental health subscale improvement was one of the strongest findings, worth noting if premenstrual symptoms affect your day-to-day wellbeing as much as physical comfort.

Study Limitations

• Only 49 of 60 randomized participants completed the 8-week trial, and the article summaries reviewed don't detail dropout reasons or whether they differed meaningfully between groups.
• Open-label design — participants and researchers knew which diet each person followed, which can introduce reporting bias, especially for self-reported mood and quality-of-life measures.
• Sample was limited to overweight and obese women of reproductive age at a single center in Iran, which may limit how well findings generalise to women of different body compositions, ages, or ethnic backgrounds.
• The study measured PMS, not clinically diagnosed PMDD, despite PMDD being the original topic of interest — a meaningfully more severe condition that this trial cannot speak to directly.
• Direct access to the full published results was unavailable when this article was written; figures were compiled from indexed search summaries rather than the complete original paper, so some exact statistics (such as total weight loss per group) could not be confirmed.

Source

Hosseini Hooshiar, M., et al. (2024). Does an alternate-day modified fasting diet improve premenstrual syndrome symptoms and health-related quality of life in obese or overweight women with premenstrual syndrome? A randomized, controlled trial. Frontiers in Nutrition. PMID: 38268675

Frequently Asked Questions

Does intermittent fasting help with PMS symptoms?

This randomized trial found that alternate-day modified fasting improved mood lability and expressed anger — two disruptive PMS symptoms — significantly more than a standard daily calorie-restricted diet over 8 weeks, in overweight and obese women.

Is this the same as PMDD (premenstrual dysphoric disorder)?

No. This study measured premenstrual syndrome (PMS), which is more common and generally less severe than PMDD, a distinct clinically diagnosed condition. No eligible human study on fasting and PMDD specifically was available at the time this article was written.

Did the fasting group lose more weight than the calorie-restriction group?

The available summaries didn't report exact comparative weight-loss figures for each group, so it isn't clear whether weight loss was matched between groups — a detail that matters for interpreting whether the fasting pattern itself, not just calorie deficit, drove the mood benefits.

What kind of fasting was used in this study?

Alternate-day modified fasting — alternating between very restricted "fasting" days and days of normal eating, over 8 weeks — rather than a daily time-restricted eating window like 16:8.

Should I try alternate-day fasting for PMS symptoms?

This single trial is promising but not conclusive on its own, and it studied a specific population (overweight and obese women). Anyone considering it, especially with pre-existing symptoms severe enough to affect daily functioning, should discuss it with a healthcare provider first.

Related Research and Articles

• Carb cravings before your period are normal and what to eat
• The luteal phase and fasting: why the week before your period needs different rules
• Can intermittent fasting help with PMS?
• Intermittent fasting and PMDD: can fasting ease severe PMS?
• Fasting and cortisol: how stress hormones affect women

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