PMS and water retention: why you gain 2 kg before your period
3-5 days before your period, your weight increases by 1-2 kg — this is water, not fat. Where it comes from, what intensifies it, and how to reduce swelling without diuretics.
Cycle and Hormones
The cycle is not just menstruation. It is four weeks, during each of which estrogen and progesterone are at different levels, and along with them, appetite, water retention, energy during training, and tolerance for hunger change. A woman who “loses control before her period” is not weak—she is in the luteal phase, and the method looks different during this week than it does during the first one. This section is about how to read the cycle and adapt food, the eating window, and movement to it. The main page on the topic is women’s health and the method.
21-35
days — normal cycle length
2
halves
higher
appetite in the luteal phase
1-3 kg
of water before menstruation
Four phases in a minute
Days 1-5 — menstruation: both hormones are at their lowest, blood and iron are lost with it, energy is low. Days 6-13 — follicular phase: estrogen rises, insulin sensitivity is higher, mood and energy peak, hunger is easy to tolerate. Days 13-16 — ovulation: estrogen peaks, strength and endurance are at their maximum. Days 17-28 — luteal phase: progesterone is high, body temperature is slightly higher, resting energy expenditure is a little greater, appetite is noticeably higher, you crave sweet and salty foods, the body retains water.
In this method, this means one thing: the week before your period is not the time to be strict. Details by phase — cycle and appetite: how weight and hunger change across the phases.
Cycle and method by phases
| Phase | Food | Window | Workouts | Scale |
|---|---|---|---|---|
| Menstrual 1-5 | iron: red meat, liver; salt | 12/12-14/10 | walking, mobility | do not weigh yourself |
| Follicular 6-13 | regular plate | 16/8 works easily | strongest | best time to measure |
| Ovulation 13-16 | regular plate | 16/8 | strength at peak | — |
| Luteal 17-28 | + fats and protein, magnesium | 14/10, last week 12/12 | moderate, as able | do not weigh yourself: water |
Fasting with the cycle: when to take it easier
The female body reacts more strongly to long breaks with stress than the male body, and clinics write about this openly: Cleveland Clinic advises women to start with 12 hours and not maintain a strict fasting window for two weeks before their period if it feels difficult during that time. During the luteal phase, progesterone increases appetite, while hunger-related cortisol adds to the strain — hence the cravings for sweets specifically during this week.
A practical approach: 16/8 in the first half of the cycle, 14/10 in the second, and 12/12 in the final week. This is not a setback but an adjustment. Read more — fasting and the cycle: when to take it easier, when to be stricter; for an overview of schedules — intermittent fasting schedules.
Drink 2-3 liters of water per day, add lemon and electrolytes. Salt — 3-5 g per day.
Training by phases: myth and practice
The idea of “training according to your cycle” is trendy, but the data are less impressive than the advertising: systematic reviews do not find a convincing difference in strength gains across phases, while well-being and load tolerance differ for many people. Practical application: in the first half, do the heaviest strength workouts; in the second, the same movements, but as you are able; during your period, walking and mobility without guilt.
What matters: a missed workout in the luteal phase is not a setback, but a plan. How to arrange your week — training by cycle phases; about home workouts in general — home workouts.
Swelling and “plus two overnight”
Before your period, the body retains 1-3 kg of water: progesterone and estrogen change how the kidneys work, while salt and sweets intensify the effect. This isn’t fat—it doesn’t accumulate overnight—and it goes away on the second or third day of the cycle. Weighing yourself during this week shows water and destroys motivation.
What helps: keeping salt within the recommended amount, rather than “eliminating it”—without sodium, the body retains water more strongly; magnesium; walking; sleep. What doesn’t help: diuretics and “detoxing.” More details — swelling and water before your period; about swelling on a low-carb diet in general — where the swelling goes.
Four cycle rules in the method
Mark the day of your cycle
After a month, your appetite, swelling, and weakness will become predictable rather than «sudden».
Be gentler the week before your period
A 12/12 window, slightly more fat and protein, magnesium, workouts as you can manage.
Iron during your period
Red meat, liver, seafood. Blood is lost every month—and iron goes with it.
Weigh yourself in the same phase
Compare your weight only with the same phase a month ago. Better yet—days 6-10.
Common mistakes
- Stick to 16/8 all week before your period and then binge
- Weigh yourself during the luteal phase and draw conclusions
- Cut out salt “to reduce swelling”
- Schedule intense workouts during your period “so you don’t skip them”
- Consider increased appetite before your period a character flaw
- Ignore a missing or irregular cycle — see a doctor
Frequently asked questions
Why do I crave sweets before my period?
Progesterone increases appetite, serotonin is lower during this phase, and craving sweets is a way to raise it. On a low-carb diet, this is milder: without blood sugar swings, but more fat and protein are needed during the luteal phase.
My cycle disappeared after changing my diet. What should I do?
First, check whether you're eating too little: a sharp calorie deficit and cutting fat are the most common cause. Restore fat and protein until satiated. If your cycle is absent for two months, see a doctor; this is not “adaptation”.
Can I fast during my period?
Gently — 12/12 — is okay if it feels easy. Strict fasting is not recommended: you lose iron and have little energy. These are days for walking, iron, and salt.
How much water is lost after your period?
1-3 kg in 2-3 days. So “minus two over the weekend” on the second day of the cycle is also water, not a result.
Section articles
Cycle Phase Training: When It Is Hard and When It Is Easy
Strength, endurance, and recovery change throughout the cycle. Where to schedule heavy strength training, where to walk, and why it is normal not to set a record during the luteal phase.
Fasting and the cycle: when 16/8 works and when it causes harm
Intermittent fasting for women depends on the phase of the cycle. When the window can be kept strictly, when to shorten it, and what signs indicate that it is too much.
Appetite and the menstrual cycle: why you want to eat before your period
In the week before your period, appetite increases by 100-300 kcal — it’s progesterone, not weakness. How to structure your food around the phases so you don’t lose control.
Reviewed by Anastasia Zhukova, Fitness Trainer • Author of a Nutrition and Training System • Creator of an AI Personal Support Platform
A human has reviewed this material against the method and real client practice.