Should you eat in line with your menstrual cycle? Dr Linia Patel explores menstrual cycle nutrition

Should your menstrual cycle inform what you eat? Dr Linia Patel (PhD), RD explores what menstrual cycle nutrition means for female athletes and everyday performance.

Recently, I had the privilege of speaking at the WHX Thrive Performance Nutrition in an African Context conference – the first of its kind, and wow, was it time well spent! One of my favourite sessions was a debate between two brilliant sports medicine doctors – Dr Phatho Zondi and Dr Nicola Frietas. It was exactly how science should be shared: interpreted, debated and translated – not reduced to a catchy social media soundbite. The debate format made it easy to see both sides of the argument. So, in this blog, I’m going to do my best to do the same for you.

The data gap: Why women are still understudied

Let’s start with the elephant in the room: women are still significantly under-represented in research. Across more than 5,200 papers published in six leading sports science journals between 2014 and 2020, only one third of participants were female and just 6% of studies were conducted exclusively on women. The result? A science gap that means women are understudied, under-represented and often undertreated. The reality is that findings from male-based research may not always apply to women. The good news is that this is changing – slowly. Researchers are pushing to close this gap, but yes, fluctuating hormones make studying women complex.

The physiology: Why hormones matter

The major difference between male and female physiology comes down to hormones – and the menstrual cycle. The menstrual cycle typically spans 21–35 days, starting from the first day of bleeding, until menopause. It’s commonly split into two phases:

• Follicular phase (Day 1 of bleeding → ovulation)
• Luteal phase (Ovulation → next period)

But within these phases, the hormonal landscape changes dramatically:

• Early follicular: low oestrogen, low progesterone
• Late follicular: high oestrogen, low progesterone
• Ovulation: moderate oestrogen, low progesterone
• Mid-luteal: moderate oestrogen, high progesterone

These hormones influence appetite, energy needs and metabolism. For example:

• Oestrogen may suppress appetite.
• Progesterone may increase it (hello, pre-period cravings!).
• Energy requirements may be slightly higher in the luteal phase.
• Fuel use shifts – with carbohydrate and fat metabolism varying across the cycle.
• The luteal phase may be more catabolic (less favourable for muscle building).

In some nutrition circles, there’s a popular piece of advice that says during the first half of your cycle you can push harder in training and get by on fewer calories, while in the second half you should increase your intake, prioritise recovery (especially fuelling soon after exercise) and stay on top of your protein.

The case for eating with your cycle

Here’s why some argue tailoring your nutrition to your cycle makes sense:

• Symptoms are real. Between 60–93% of female athletes report menstrual symptoms such as mood changes (90.6%), fatigue (86.2%) and cramps (84.2%). Around 65% say their cycle directly affects performance. These symptoms impact training, recovery and nutrition – and they can’t be ignored.
• Biology supports it. Mechanistically, different phases of the cycle do change hormone levels, energy needs and, potentially, fuel use.
• Small changes matter in sport. Even if average research findings suggest no major impact, the ‘outliers’ (those who respond differently) get lost in the data. In elite performance, where 1% matters, even small differences are important.

The case against: Why it may not make a difference

Now for the other side:

• Big studies don’t show meaningful differences. Meta-analyses (one big study by combining the results of lots of smaller studies on the same topic) suggest effects are small, inconsistent and often riddled with methodological challenges.
• Tracking isn’t perfect. It’s difficult to know exactly when ovulation happens, even with apps. Ovulation kits are more accurate but not very practical for large-scale studies or everyday use.
• Big rocks first. When you focus too much on ‘eating for your cycle’, you risk losing sight of the fundamentals: consistent fuelling, progression and recovery. Limiting yourself to ‘only going hard’ two weeks of the month could actually hold you back.
• Team sport reality check. How does a coach tailor training and menstrual cycle nutrition for 20 players, each in different phases of their cycle, when match day isn’t cycle-dependent?
• Smarter alternative. Building self-awareness and tracking your own symptoms may be a more powerful and practical strategy than prescriptive cycle-based eating.

The food for thought

To be honest, when the conversation in this space first started, I was super excited. As a performance nutritionist working mainly with women, the idea of moving towards more personalised nutrition felt like a breakthrough. Mechanistically, the biology is fascinating – hormones do shift and it makes sense that nutrition might need to shift with them.

But when I put my evidence-based hat on, the reality is this: the science just doesn’t stack up (yet) to justify broad, generalised prescriptions for women based purely on menstrual cycle phase.

So, where does that leave us?

• Research findings conflict – partly because methodology varies so much.
• Every woman experiences her cycle differently. PMS, PMDD, appetite, mood and fatigue can range from subtle to overwhelming.
• Increases in daily energy needs from the follicular to luteal phase vary widely in the literature – anywhere from 90 to 500kcal/day. Most studies suggest around 200-350kcal/day but some show no change at all.
• The lack of universal patterns means a personalised approach is best.

The bottom line

Here’s what we know:

• Women deserve better science – and we need more high-quality research that actually studies women.
• Lack of evidence isn’t the same as no
• For now, the strongest performance principles still stand: train smart, fuel well, recover properly.

And, most importantly, you are an individual.

Know yourself. Track your symptoms. Notice patterns. Support yourself with the basics and tweak where needed.

That’s how you truly eat – and perform – in sync with your body.

Read more on the FitPro blog around training in your menstrual cycle with Debby Sargent

References

1. WHX Thrive Cape Town, South Debate on Menstrual Cycle.
2. Rogan M et al (2022), Dietary energy intake across the menstrual cycle: a narrative review, 81(7): 869-86.
3. Brown N et al (2023), Nutritional practices to manage menstrual cycle related symptoms: A systematic review, Nutrition Research Reviews, 36(2): 255-80.
4. Carmichael M et al (2023), Dietary energy intake across the menstrual cycle: A narrative review, Nutrition Reviews, 81(7): 869884.
5. Elliott-Sale K et al, Effects of menstrual cycle phases on athletic performance and related traits, Journal of Applied Physiology, 128(2): 349-61.
6. Findlay RJ et al (2025), UEFA expert group statement on menstrual cycle and sport: How to track, manage and apply knowledge in elite women’s football, BMJ Open Sport & Exercise Medicine, 11(3).
7. Guest NS et al (2024), Inconsistencies in the perceived impact of the menstrual cycle on sport and exercise, Journal of Science and Medicine in Sport, 27(4): 371-79.
8. McNulty K et al (2022), The effects of the menstrual cycle on perceptual responses in athletes: A systematic review and meta-analysis, Frontiers in Psychology, 13:
9. Taati B et al (2024), The influence of menstrual cycle phases on maximal strength performance in healthy female adults: A systematic review and meta-analysis, Sports Medicine, 54(1): 37-55.
10. Tucker C et al (2025), Effect of the menstrual cycle on energy intake: A systematic review and meta-analysis, Nutrition Reviews, 83(3): e866–e884.
11. Van Dongen M et al (2024), Food-related exploration across the menstrual cycle, Appetite, 196: