Nutrition advice is largely built on averages, average body, average hormone levels, average need. For women, that average smooths over a monthly cycle of genuine variation. Your calorie requirements, your micronutrient needs, your gut sensitivity, and your body's capacity to use different nutrients all shift across your cycle. Here's what that actually looks like, phase by phase.
Menstrual phase (days 1-5): replenish and reduce inflammation
Iron: You're losing iron through blood loss. Haem iron (from animal sources: red meat, shellfish) is most easily absorbed by the body. Non-haem iron (from plant sources: lentils, spinach, tofu) is less bioavailable but still valuable. For both, vitamin C significantly boosts absorption — pair with vitamin C-rich foods like orange juice, bell peppers, or strawberries, or take a supplement alongside. This is not the week to skip the steak.
Omega-3s: Prostaglandins, the compounds that drive menstrual cramping, are inflammatory. Omega-3 fatty acids compete with the inflammatory prostaglandin pathway, reducing their production. Oily fish, walnuts, and flaxseed are your best dietary sources. (Deutch B, European Journal of Clinical Nutrition, 1995)
Magnesium: Magnesium helps relax smooth muscle and has been shown to reduce the severity of menstrual cramping. 200–400mg magnesium glycinate is a well-tolerated supplemental option. Food sources include dark chocolate (our fave), pumpkin seeds, and leafy greens. If diet isn't sufficient, a magnesium glycinate supplement is well absorbed and well tolerated.
Calorie intake: Slightly elevated in the late luteal / early menstrual phase. Your body's basal metabolic rate is measurably higher, by approximately 100–150kcal/day, in the luteal phase. Don't fight the hunger.
Follicular phase (days 6-13): build and perform
This is your highest-energy phase. Oestrogen is rising, appetite may be lower than usual, and your body is primed for protein synthesis and adaptation.
Protein: Prioritise protein intake around training sessions. Your anabolic window is widest here, protein consumed pre- and post-training converts to muscle adaptation most efficiently when oestrogen is high. Aim for 1.6–2.2g/kg of bodyweight across the day. (Morton RW, et al., British Journal of Sports Medicine, 2018)
Complex carbohydrates: Insulin sensitivity is at its best in the follicular phase. This is the time for higher-carb approaches around training, glycogen storage and usage are more efficient.
Antioxidants: Support the increased training load with antioxidant-rich foods: berries, leafy greens, green tea. Oxidative stress from hard training sessions is more manageable here, but recovery nutrition still matters.
Ovulatory phase (days 14-17): peak and protect
A brief but important window. Energy is peaking, coordination is at its best, and ligament laxity increases slightly under peak oestrogen, raising soft tissue injury risk.
Zinc: Zinc plays a role in the LH surge that triggers ovulation and supports immune function, which can dip around ovulation. Oysters, pumpkin seeds, and beef are high-yield sources.
Fibre: Oestrogen is metabolised through the gut. Adequate fibre supports efficient oestrogen metabolism and clearance, preventing recirculation of used oestrogen. Aim for 25–30g daily from whole food sources.
Hydration: Core temperature and metabolic rate both increase around ovulation. Hydration needs go up, particularly if training hard.
Luteal phase (days 18-28): fuel and support
This is the most nutritionally demanding phase. Calorie needs are higher, hormonally driven cravings are real, and the body is under more physiological stress.
Magnesium and B6: The combination of magnesium and vitamin B6 has the most research support for reducing luteal phase symptoms, including mood fluctuation, bloating, and cramping. B6 supports serotonin synthesis; magnesium supports progesterone receptor function and also aids sleep quality and muscle recovery. (Wyatt KM, et al., British Medical Journal, 1999)
Complex carbohydrates: Serotonin synthesis requires tryptophan, which is best absorbed alongside carbohydrate. The carbohydrate cravings of the luteal phase may partly be the brain seeking serotonin precursors. Research from Dr. Stacey Sims also suggests adequate complex carbohydrate intake supports progesterone function, helping it rise efficiently for a healthy period. Whole grains, sweet potato, and legumes are preferable to refined sugar — they provide sustained energy without the spike-and-crash cycle.
Anti-inflammatory foods: Progesterone increases gut permeability and inflammatory sensitivity. Dark leafy greens, turmeric (with black pepper to activate absorption), and oily fish all support anti-inflammatory pathways. If oily fish isn't your thing, an omega-3/DHA supplement is an equally effective alternative.
Protein and EAAs: Protein remains important for muscle repair throughout this phase. If heavy whey protein doesn't sit well with you in the luteal phase — it can cause bloating and gut issues — essential amino acids (EAAs) are a lighter, highly bioavailable alternative. Look for a high-quality, minimal-ingredient option rather than a proprietary blend.
Reduce caffeine and alcohol: Both exacerbate luteal phase symptoms. Caffeine amplifies anxiety and disrupts sleep (which is already compromised). Alcohol worsens mood regulation and sleep quality. Even a small reduction makes a measurable difference in how the phase feels.
The bottom line
Eating the same foods in the same quantities every day of the month is nutritionally neutral at best and actively counterproductive at worst. Your body's needs are cyclical. Matching your nutrition to your phase isn't restriction, it's precision. Start with one phase, track how you feel, and build from there.