Many women notice their weight, hunger and energy change across the month. These shifts are normal and predictable — and planning for them makes dieting far less frustrating.

Weight changes across the cycle

Water retention commonly rises in the days before a period and falls again once it starts. It's usual to see the scale jump 1–2kg temporarily. Compare your weight to the same point in your previous cycle rather than to last week.

Appetite and cravings

Many women report increased hunger and cravings in the second half of the cycle (the luteal phase). Some research suggests energy expenditure rises slightly in this phase too, but the difference is small — roughly the size of a snack.

Practical strategies

• Expect it: note your cycle so a pre-period weight jump doesn't feel like failure.
• Plan extra volume: add filling, high-fibre foods and a little more protein in the days before your period.
• Allow a little flexibility: a planned 100–200 kcal snack can prevent a bigger unplanned binge.
• Adjust training: if energy dips, keep training but reduce intensity rather than skipping it.
• Iron: heavy periods increase iron needs — include red meat, pulses, fortified cereals and leafy greens.

When to seek advice

Very heavy, painful or irregular periods, or missed periods during a diet, are worth discussing with your GP. Missing periods can be a sign that energy intake is too low for your activity level.