This is not medical advice. General information about food tracking and weight change, not a treatment plan. If you are under 18, pregnant or breastfeeding, have ever had an eating disorder or a difficult relationship with food, or are managing a medical condition, talk to a doctor or a registered dietitian before you start counting calories or change your intake. Premenstrual symptoms severe enough to disrupt your life are a medical question rather than a tracking one. The full list is here.

What the scale actually does across a cycle

Start with the instrument, because most of what a scale reports over a fortnight is not fat.

Researchers followed 46 adults across two cohorts under ordinary free-living conditions for two weeks, measuring total body water by isotope dilution in one group and repeat DXA scans in the other. Average weight change was 0.26 kg with a standard deviation of 1.2 kg, and when they decomposed those changes, a unit change in body weight was 84% change in fat-free mass. The energy density of the 1 to 3 kg short-term swings averaged 2,380 kcal per kg.2 Fat tissue is closer to 7,700 kcal per kg.3 That is the noise floor every reader of a scale is already standing on, cycle or no cycle.

The cycle adds its own signal on top. A Greek group measured body weight, circumferences, skinfolds and body composition by bioelectrical impedance twice a week in 42 women through a menstrual cycle. Body weight was significantly higher during menstruation than during the first week of the cycle, by 0.450 kg, and that difference tracked a significant increase of 0.474 kg in extracellular water. No other index of body composition changed significantly. The authors' conclusion is the sentence worth keeping: an increase of about 0.5 kg was observed, mostly due to extracellular fluid retention at menstruation days, and clinicians dealing with weight management in women of reproductive age should read those increases as expected water retention rather than as gains in fat mass.1

Take the size of that study seriously before you take the number. Forty-two women, one cycle each, and bioimpedance is an indirect method that infers composition from how the body conducts a current, which makes it sensitive to exactly the hydration shift it was being used to measure. It is a well-designed small study, not a definitive one.

Put the two together and the practical point survives the caveats. Half a kilo of cycle-driven water lands on top of a kilo or more of ordinary week-to-week variation, and none of it is the thing you are trying to change. A morning where the number is up 1 kg is unremarkable, and it was unremarkable before your cycle got involved.

Do you eat more in the luteal phase?

On average, yes, and the size of it has now been pooled properly.

A 2025 systematic review and meta-analysis in Nutrition Reviews gathered 15 datasets covering 330 women, mean age 26, mean BMI 22.4, all of them aged 18 to 45 with no history of disordered eating. Energy intake was significantly higher in the luteal phase than the follicular phase, with a standardised mean difference of 0.69 and a crude average difference of 168 kcal per day.4

The authors are blunt about what they had to work with. They report repeated methodological inconsistencies across the included studies and call for future work that uses best practice for both energy intake measurement and menstrual phase specification.4 Read the direction as solid and the 168 as a rough central estimate, not as your number.

The composition of the change has been looked at too. The BioCycle study followed 259 healthy regularly menstruating women aged 18 to 44 for up to two cycles, taking 24-hour dietary recalls and craving questionnaires up to four times per cycle. Total protein, animal protein and the percentage of calories from protein were all highest in the mid-luteal phase compared with the peri-ovulatory phase. Appetite and cravings for chocolate, for sweets generally and for salty flavours were all significantly higher in the late luteal phase than in the menstrual, follicular and ovulatory phases, and this held independent of whether the cycle was ovulatory.5

Those are 24-hour recalls, which are self-report, and self-report under-counts food. Here that matters less than usual, because the comparison is within the same women at different points in their own cycle, so a bias that stays constant across the cycle largely cancels out. It only cancels if it does stay constant, which nobody has established.

Does your metabolism speed up before your period?

This is the answer I see used to cancel out the previous section, and it does not hold up well enough to do that job.

A meta-analysis in PLOS ONE searched five databases and reviewed 30 studies published between 1930 and 2019, pooling 26 of them covering 318 women. Overall there was a small but significant effect favouring higher resting metabolic rate in the luteal phase, with an effect size of 0.33 (95% CI 0.17 to 0.49, p < 0.001). The sub-group analysis is the interesting part: in studies published since 2000, the effect was smaller and no longer statistically significant, at 0.23 (95% CI -0.00 to 0.47, p = 0.055).6

The authors list their own problems: risk of bias in how both the cycle and resting metabolic rate were measured, small samples throughout, and studies that did not report controlling for confounders. Their recommendation was aimed at researchers rather than dieters, and it was to test consistently in one phase of the cycle so that the cycle stops contaminating the measurement.6

So any real premenstrual rise in resting expenditure is small, and it has been shrinking as the methods have improved. It is not a licence to add a few hundred calories to a target, and no calorie tracker app I know of adjusts for it, mine included.

What 168 calories a day is actually worth

Take a 14-day luteal phase inside a 28-day cycle as the working assumption, knowing that both vary between women and between cycles, so what follows is an order of magnitude and not a measurement. Fourteen days at 168 extra calories comes to about 2,350 calories. At around 7,700 calories per kilogram of fat tissue3 that is close to 0.3 kg of fat, if none of it is offset anywhere else. Spread across the whole cycle it works out at 84 calories a day, which is about 4% of a 2,000-calorie day.

Now the caveat that makes the estimate softer than it looks. The meta-analysis compared the luteal phase against the follicular phase in the same women.4 It does not tell you that the luteal phase sits above your maintenance requirement, only that it sits above your own follicular intake. If your follicular weeks run under maintenance, which is the entire point if you are counting calories to lose weight, then a luteal rise of that size can close part of a deficit without creating a surplus at all.

Set that against the water. The swing that frightens people is about 0.5 kg and it reverses on its own.1 The change actually made of tissue is at most about 0.3 kg, and it accumulates over a fortnight, so it is invisible on any given morning and buried under the water on exactly the mornings you are most likely to look.

How to read calorie tracking data across a cycle

None of the above changes what you eat. It changes what you compare against what, and there are four rules that fall out of it.

The first is that the unit of comparison is a cycle, not a week. Day 8 of this cycle against day 8 of the last one tells you something. This Monday against last Monday, when the two sit in different phases, mostly measures the phase. Four weeks of seven-day averages is the usual advice for reading a weight trend, and on a 28-day cycle that happens to be one full turn, which is convenient rather than coincidental.

The second is to keep weighing through the premenstrual week rather than skipping it. Skipping the high mornings does not remove them from the trend, it removes them from your view of the trend and makes the average look better than the body is. A systematic review of 17 longitudinal studies found regular self-weighing associated with greater weight loss, and not associated with adverse psychological outcomes such as depression or anxiety, though the effect sizes and weighing frequencies varied a lot between studies.9 Those are associations in people already seeking weight-loss treatment rather than a randomised effect of the scale itself.

The third is not to change your calorie target on a premenstrual reading. Your target is arithmetic on your height, weight, age, sex and activity, and a fortnight of extracellular water has not altered any of those. Whatever the case for adjusting a target, a bad Tuesday in the week before a period is not it, and there is a floor underneath any adjustment: the NIH clinical guidelines put the lowest reasonable unsupervised intake at 1,200 calories a day for women.10

The fourth is to log the luteal days honestly, especially the ones with the cravings in them.5 That is the week a food tracker for weight loss is most often abandoned and the week it has most to tell you. A log that quietly stops on the hard days is a record of the easy ones.

Write the cycle day next to your weigh-in for three cycles before you conclude anything. Three points is enough to see whether you have a pattern and cheap enough that it costs you nothing if you do not. The published averages describe groups of a few hundred women; only your own log describes you.

Here is the part where I criticise my own app. MyPlate has no cycle tracking in it. There is no field for a cycle day, nothing marks a week as luteal, and it does not read cycle data from Apple Health because it does not use HealthKit at all. The Analytics screen charts weight day by day for the current month and month by month beyond that, with a single average for whichever range you pick, and there is no seven-day rolling average anywhere in it. So the comparison described above is one you do yourself, in a notes app or on paper. I would rather write that down than let a post on my own site imply the app does something it does not.

If you are on hormonal contraception

It would be reasonable to assume hormonal contraception flattens all of this, and the evidence is more specific than that.

A study of 1,102 women in the Toronto Nutrigenomics and Health Study recorded premenstrual symptoms and contraceptive use. The most commonly reported symptoms were cramps and bloating at 75% each, mood swings at 73%, increased appetite at 64% and acne at 62%. Hormonal contraceptive use was associated with a lower risk of moderate or severe cramps, clumsiness, confusion and desire to be alone. It was not associated with the risk of bloating, increased appetite, anxiety, mood swings, acne, fatigue, depression, nausea, headache or insomnia, and it was not associated with symptoms at mild severity at all.7

The two symptoms most likely to move a number in your log, bloating and increased appetite, are on the list that contraceptive use was not associated with improving. So do not assume that being on something means the pattern in this article does not apply to you.

The limits are worth stating plainly. This is a cross-sectional association in one multiethnic cohort, symptom severity was self-reported, and every formulation was pooled into one exposure called hormonal contraceptive use. It gives you a reason not to assume, without proving the opposite. If your contraception has left you without a predictable cycle to align anything to, then there is nothing to compare phase to phase and you are back to ordinary rolling averages, which were always the fallback.

What the evidence does not settle: cycle syncing

Search any of this and you will be sold a phase-by-phase plan: eat this way in your follicular phase, train that way in your luteal. The strongest synthesis that touches the question does not support prescriptions of that kind, and it is worth reading in full instead of as a headline.

A team led from Northumbria University reviewed 78 studies of menstrual cycle phase and exercise performance, meta-analysing 51 of them pairwise and 73 in a network meta-analysis using Bayesian multilevel models. They found a trivial effect for both endurance and strength outcomes, with slightly reduced performance in the early follicular phase, at a median pooled effect size of -0.06 (95% credible interval -0.16 to 0.04). The largest single contrast, early follicular against late follicular, came to -0.14 (95% CrI -0.26 to -0.03). They graded the quality of the evidence as low, at 42%.8

Because of the trivial effect size, the large between-study variation and the number of poor-quality studies, they concluded that general guidelines on exercise performance across the cycle cannot be formed, and recommended a personalised approach based on each individual's own response instead.8

That review is about exercise performance, not about calories or macros, and I could find no comparable synthesis of phase-based eating prescriptions at all. So the best-powered synthesis of any cycle-phase question found a trivial effect in studies it graded low, and the nutrition version has never been pooled to that standard by anyone. A phase-by-phase meal plan is a long way ahead of what has been shown.

What the same authors do endorse is the individual version, and that is available to you for the price of writing a number down. Track your own cycles for a few months and see whether you have a pattern worth planning around. Some people do. The difference is that you would be reading it out of your own log, not out of a template built on studies the reviewers themselves graded low.

When it is not your cycle

A cycle-shaped explanation is only good for a cycle-shaped pattern, and it has to do two things to earn the name. It has to repeat, and it has to reverse. Weight that climbed in the premenstrual week and came back down two weeks later is doing what this article describes. Weight that went up in March and never came back down is not, whatever week it started in.

If your trend has been genuinely flat across several full cycles, the explanations are the ordinary ones and I have been through them elsewhere: the four-week test for whether a stall is real, the target that goes stale as you get lighter, and where the missing calories usually hide are all in the piece on why the scale stopped moving. If your weight is climbing after a period of successful loss, the relevant question is what your body now costs to run, which is the subject of the maintenance calories piece. Neither of those is about your cycle, and reaching for the cycle first will cost you a month.

Two things sit outside what an app or an article can help with. Premenstrual symptoms severe enough to disrupt your sleep or your work are a medical question, not a tracking one, and they belong with a doctor instead of a spreadsheet. And if the scale has become something you check three times a day, or the log has started deciding whether the day went well, that is the point to stop and talk to your doctor or a registered dietitian. Better measurement does not fix it and more of it usually makes it worse.

Common questions

Why does my weight go up before and during my period?

Because you are holding more water, not more fat. Measuring 42 women twice a week through a cycle, researchers found body weight about 0.450 kg higher during menstruation than during the first week of the cycle, matched by a 0.474 kg rise in extracellular water, with no significant change in any other index of body composition. Their own conclusion was that clinicians should read those increases as expected fluid retention rather than as gains in fat mass.1 That half kilo also arrives on top of ordinary week-to-week variation, which in free-living adults runs to a standard deviation of 1.2 kg over two weeks and is 84% fat-free mass.2 It reverses on its own within a few days.

Should I eat more calories in my luteal phase?

Not as a rule, and the number people quote is smaller than it sounds. A meta-analysis of 15 datasets covering 330 women found energy intake significantly higher in the luteal phase than the follicular phase, by a crude average of 168 calories a day, with the authors noting repeated methodological inconsistencies in the studies they pooled.4 That comparison is against your own follicular intake, not against your maintenance requirement, so if your follicular weeks sit in a deficit a luteal rise of that size may only narrow it without creating a surplus. Over a full 28-day cycle it averages about 84 calories a day. If you want a deliberate plan, raise intake slightly across the whole cycle rather than improvising in one week, and never below 1,200 calories a day for women without a clinician involved.10

Does your metabolism speed up before your period?

A little, possibly, and less than it used to appear. A meta-analysis pooling 26 studies and 318 women found a small but significant effect favouring higher resting metabolic rate in the luteal phase, at an effect size of 0.33, but in the studies published since 2000 the effect fell to 0.23 and was no longer statistically significant. The authors flagged risk of bias in how both the cycle and resting metabolism were measured, small samples throughout, and studies that did not report controlling for confounders.6 It is not a large enough or certain enough effect to build a calorie target around, and no mainstream tracker adjusts for it.

Should I stop weighing myself during my period?

No, keep weighing and change what you compare instead. Skipping the high mornings does not take them out of your trend, only out of your view of it. Compare the same point in one cycle against the same point in the next, instead of this week against last week, since two weeks a fortnight apart usually sit in different phases. A systematic review of 17 longitudinal studies found regular self-weighing associated with greater weight loss and not associated with adverse psychological outcomes such as depression or anxiety, although effect sizes and weighing frequencies varied a lot across the studies, and these are associations in people already seeking weight-loss treatment, and not a randomised effect of the scale.9

Does hormonal contraception stop period weight gain?

Not for the two symptoms most likely to move your log. Among 1,102 women in the Toronto Nutrigenomics and Health Study, hormonal contraceptive use was associated with a lower risk of moderate or severe cramps, clumsiness, confusion and desire to be alone, but was not associated with the risk of bloating or increased appetite, which were reported by 75% and 64% of the sample respectively.7 That is a cross-sectional association in one cohort with self-reported symptom severity and all formulations pooled together, so treat it as a reason not to assume, not as proof. If your contraception has left you without a predictable cycle, there is no phase to compare against and rolling averages are the fallback.

What is the best calorie tracker app if my weight swings with my cycle?

Judge it on three things, none of which is a cycle feature. It should make logging fast enough that you still do it in the week the cravings arrive, because that is the week most logs quietly stop and the week they have most to say.5 It should chart weight over months rather than days, so you can set one cycle beside the next instead of reading a single morning. And it should let you recalculate your calorie target when your body has actually changed, which a fortnight of extracellular water is not.1 On that last count MyPlate is honest but not clever: it has no cycle tracking, does not use HealthKit, and shows one average for whichever range you select instead of a rolling seven-day line, so the phase-to-phase comparison is something you do yourself. Apple's own Health app records cycle days and weight together if you want them in one place, and MyPlate does not connect to it.

Compare like with like

Nearly everything above resolves into one instruction, and it is about comparison, not about food. You carry roughly half a kilo of extra water around your period and give it back a few days later.1 Your appetite really is higher in the run-up, by something around 168 calories a day at the group level, measured against your own follicular baseline rather than against your maintenance requirement.4 Your resting metabolism may rise a little, and the better-conducted studies keep finding less of it.6 None of those is large next to the noise a scale produces anyway, and all of them repeat on a schedule, which is the only reason they can be read at all.

So compare like with like: the same point of one cycle against the same point of the next. Weigh through the week you would rather skip, log the days with the cravings in them, and leave your calorie target alone until you have three cycles of your own data instead of one bad Tuesday. If there is a pattern, you will see it, and it will be yours and not a template's.

If there is no pattern, that is a result as well. It means whatever the scale is doing has one of the ordinary explanations, and those are all in the piece on why the scale stopped moving.

Sources

Every figure above traces to one of these. If you find a number that doesn't match the source it claims, tell me and I'll correct it.

  1. Kanellakis S, Skoufas E, Simitsopoulou E, et al. (2023). Changes in body weight and body composition during the menstrual cycle. American Journal of Human Biology, 35(11):e23951. Read on PubMed →
  2. Bhutani S, Kahn E, Tasali E, Schoeller DA (2017). Composition of two-week change in body weight under unrestricted free-living conditions. Physiological Reports, 5(13):e13336. Read on PubMed →
  3. Thomas DM, Gonzalez MC, Pereira AZ, Redman LM, Heymsfield SB (2014). Time to correctly predict the amount of weight loss with dieting. Journal of the Academy of Nutrition and Dietetics, 114(6):857-861. Read on PubMed →
  4. Tucker JAL, McCarthy SF, Bornath DPD, Khoja JS, Hazell TJ (2025). The effect of the menstrual cycle on energy intake: a systematic review and meta-analysis. Nutrition Reviews, 83(3):e866-e876. Read on PubMed →
  5. Gorczyca AM, Sjaarda LA, Mitchell EM, et al. (2016). Changes in macronutrient, micronutrient, and food group intakes throughout the menstrual cycle in healthy, premenopausal women. European Journal of Nutrition, 55(3):1181-1188. Read on PubMed →
  6. Benton MJ, Hutchins AM, Dawes JJ (2020). Effect of menstrual cycle on resting metabolism: a systematic review and meta-analysis. PLOS ONE, 15(7):e0236025. Read on PubMed →
  7. Jarosz AC, Jamnik J, El-Sohemy A (2017). Hormonal contraceptive use and prevalence of premenstrual symptoms in a multiethnic Canadian population. BMC Women's Health, 17(1):87. Read on PubMed →
  8. McNulty KL, Elliott-Sale KJ, Dolan E, et al. (2020). The effects of menstrual cycle phase on exercise performance in eumenorrheic women: a systematic review and meta-analysis. Sports Medicine, 50(10):1813-1827. Read on PubMed →
  9. Zheng Y, Klem ML, Sereika SM, et al. (2015). Self-weighing in weight management: a systematic literature review. Obesity, 23(2):256-265. Read on PubMed →
  10. National Heart, Lung, and Blood Institute, NIH (1998). Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. NIH Publication 98-4083. Read the guidelines →

The formulas and limits behind MyPlate's own numbers, with their citations, are on the health sources page.