Hormonal changes and your menstrual cycle: What to expect when losing weightUpdated a day ago

Losing weight is an exciting step towards better health. It often brings many positive changes—more energy, a better mood, and increased confidence. But did you know that weight loss can also affect your hormonal balance and menstrual cycle?

What’s Going On?

When you lose weight, your body’s hormonal balance can shift. This happens because hormones like oestrogen, progesterone, and others are closely linked to body fat and metabolism. Even a modest weight reduction can influence how these hormones interact, which may affect your menstrual cycle.

What Might You Notice?

As your body adjusts, you may experience:

• Changes in your period flow – Periods might become lighter or heavier than usual.
• Differences in duration – Some women find their periods are shorter or longer.
• Frequency variations – Your cycle may become more irregular, or your periods might arrive more or less often than expected.

These changes are usually temporary and tend to settle as your body adapts to its new state.

A Note About Contraception

Even if you’re taking hormonal contraception, weight loss can still bring about changes in your cycle. You might notice:

• Unexpected bleeding or spotting
• Shifts in the timing of your period

This happens because weight loss can influence natural hormone levels in the body, which may interact with the hormones in your contraception.

And Don’t Forget About Water Weight

During hormonal changes, especially around your period, you might experience increased water retention. This can show up as temporary bloating or a small increase on the scales.
It’s completely normal and not a sign of fat gain—just a natural part of your cycle. Try not to be discouraged; this usually resolves within a few days.

Why Does This Happen?

Body fat plays a key role in producing and regulating hormones, particularly oestrogen. When fat levels decrease, the levels of certain hormones may drop too, which can temporarily disrupt your menstrual cycle. This is more likely if:

• Weight loss is rapid or significant
• You're following a very low-calorie diet
• You're experiencing high levels of stress or exercising intensely

Should You Be Worried?

In most cases, menstrual changes during weight loss are normal and temporary. Your cycle should return to its usual rhythm once your body adjusts. However, you should speak to a healthcare professional if:

• Your periods stop completely for three months or more (this is called amenorrhoea)
• You experience severe symptoms like heavy bleeding or intense cramps
• You’re trying to conceive and are concerned about your fertility

Be Kind to Your Body

Your body is truly amazing and resilient. Hormonal shifts during weight loss are a natural part of the process and usually nothing to worry about. Focus on nourishing your body, getting enough rest, and staying consistent with your healthy habits.

Remember: Progress isn’t just about the number on the scales. Your overall health, hormonal balance, and emotional well-being are just as important. Stay patient, stay informed, and be proud of every step you take towards feeling your best.