The week before your period, everything is a little louder. The jeans fit differently, the group chat is more annoying than it was on Tuesday, and you'd trade a kidney for a bag of salt and vinegar chips at 4 p.m. Food won't switch that off, but it can turn the volume down. Here's what we eat that week and why, with a chart at the end you can screenshot.
What PMS is, and why the week before matters
By ACOG's definition, PMS is a pattern of physical or mood symptoms in the five days before a period, present for at least three cycles in a row, that eases within four days of bleeding starting. That five-day window is the target, though some of this works better if you start earlier.
Calcium foods: the best-studied PMS food
If one nutrient has earned its place, it's calcium. In the largest PMS nutrient trial we can find, 497 women took 1,200 mg of calcium a day or a placebo for three cycles. By the third cycle the calcium group's total symptom score had dropped 48% from baseline, against 30% on placebo, and all four symptom groups (mood, water retention, cravings and pain) improved.
Food seems to count as well as pills. A study nested in the Nurses' Health Study II followed women for ten years and found that those eating the most calcium from food, around 1,280 mg a day, were 30% less likely to develop PMS than those eating the least, around 530 mg. Skim and low-fat milk in particular tracked with lower risk. Yogurt, milk, fortified plant milks, calcium-set tofu, sardines and kale get you there.
The honest part: that trial took three cycles to show its full effect. A week of yogurt is a start, not the study.
Magnesium foods for bloating and mood
Magnesium has two small trials behind it. A crossover trial of 200 mg a day found no difference in the first month and a clear drop in bloating, breast tenderness and swelling in the second. An earlier trial of 32 women taking 360 mg from mid-cycle to bleeding found the mood cluster improved more on magnesium than placebo. Both are small, so read them as promising rather than settled.
The foods are easy: pumpkin seeds, almonds, spinach, black beans, oats and dark chocolate. A handful of seeds on whatever you're already eating is the lowest-effort version. Our foods that ease period cramps guide covers the bleeding days; this is the week before.
B vitamins: from food, not from a pill
This one has a twist. The same Nurses' Health Study II cohort found that women with the highest riboflavin (B2) intake from food had a 35% lower risk of developing PMS, and thiamine (B1) from food tracked the same way. B vitamins from supplements showed no link at all. Riboflavin lives in eggs, milk, yogurt, mushrooms and almonds; thiamine in oats, lean pork, beans and sunflower seeds. Vitamin B6 is the one you'll see sold for PMS, and a BMJ systematic review did find doses up to 100 mg a day likely helped, but the authors were blunt that the trials were poor quality. Food first.
Complex carbs and smaller meals
Both ACOG and Mayo Clinic recommend a diet rich in complex carbohydrates that week: whole-grain bread and pasta, oats, barley, brown rice, beans and lentils. ACOG's reasoning is that a steady blood sugar helps with mood and cravings, and it suggests six small meals instead of three large ones. We have a whole piece on sugar cravings before your period if that's your week.
What to go easy on: salt, caffeine, alcohol, sugar
ACOG says to cut back on fat, salt and sugar and to avoid caffeine and alcohol; Mayo adds that limiting salt helps with bloating and fluid retention. We won't pretend we skip the chips entirely. We do keep the salty stuff to earlier in the day and swap the second coffee for a decaf that week, because sleep is already fragile around a period and caffeine makes it worse.
What we make, and why. We're a small team who has periods and reads these studies, so we make Girl Chocolate: a dark chocolate bar made for the days around your period, with magnesium and other functional ingredients, sold as a pouch of eight bars for one cycle. It's the magnesium row of the chart in the form you'd actually reach for at 4 p.m. Made for your cycle, and it supports PMS relief*.
The PMS foods chart
| If the week before brings | Reach for | Go easy on | What the evidence says |
|---|---|---|---|
| Bloating, puffiness | Pumpkin seeds, spinach, black beans, almonds, dark chocolate (magnesium); water | Salty snacks, fizzy drinks | 200 mg magnesium a day eased fluid retention in the second cycle, not the first |
| Low mood, irritability | Yogurt, milk, fortified plant milk, kale (calcium); oats, whole-grain bread, lentils (complex carbs) | Alcohol, big sugar hits | 1,200 mg calcium a day cut total PMS scores 48% vs 30% on placebo by cycle three |
| Cravings, energy dips | Six smaller meals; beans, brown rice, barley | Skipping meals, caffeine after lunch | ACOG and Mayo both recommend complex carbs and smaller, more frequent meals |
| Everything, every month | Eggs, milk, mushrooms, almonds, oats, lean pork (riboflavin and thiamine from food) | Relying on a B-complex pill | Highest food riboflavin intake had 35% lower PMS risk; supplements showed no link |
One more honest note. We tried a "perfect week" once, every row of that chart for five days, and felt about the same. The second month was noticeably better. Give it two cycles before you decide.
Print our free PMS week meal plan: five days of meals built from calcium and magnesium foods, plus a grocery list. 1 page, PDF, no email needed.
Download the PDFSources
- ACOG, Premenstrual syndrome FAQ
- Thys-Jacobs et al. 1998, Calcium carbonate and PMS (Am J Obstet Gynecol)
- Bertone-Johnson et al. 2005, Calcium and vitamin D intake and incident PMS (Arch Intern Med)
- Walker et al. 1998, Magnesium and premenstrual fluid retention (J Womens Health)
- Chocano-Bedoya et al. 2011, Dietary B vitamin intake and incident PMS (Am J Clin Nutr)
- Mayo Clinic, Premenstrual syndrome: treatment
When to talk to a doctor
Everything above is for ordinary period pain. See a doctor if the pain stops you doing daily life, if you are bleeding through a pad or tampon every hour, if the pain suddenly got much worse than your usual, or if you have pain with a fever. None of those are things to manage with a hack.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
