You feel foggy, tired, moody, and your periods have gone rogue. What’s going on?

If you’re in your late 30s or 40s and wondering why your body suddenly feels unfamiliar, you’re not alone. One day you’re crushing deadlines, the next you’re crying over an ad, and your cycle seems to be on its own schedule.

Welcome to perimenopause, a hormonal transition that can start as early as your mid-30s, long before your periods actually stop. And while it’s perfectly normal, it’s rarely talked about, leaving most women confused, dismissed, or told to just relax.

Let’s break down the real things that happen in perimenopause, why they’re happening, and how to support your body through it without losing your mind.

What is perimenopause?

Perimenopause is the phase leading up to menopause. Think of it as puberty in reverse, a time when your reproductive hormones begin to fluctuate and decline. It typically begins in your 40s but can start earlier, especially if you’ve experienced high stress, nutrient deficiencies, or autoimmune issues.

The hallmark of perimenopause is a drop in progesterone and fluctuating estrogen levels. This hormonal imbalance can affect every system in your body, including your brain, metabolism, gut, skin, and mood.

Unlike menopause, which is defined as 12 months without a period, perimenopause is an unpredictable and often bumpy ride.

1. Your periods get unpredictable

The most obvious change is your menstrual cycle. It may become shorter, longer, heavier, lighter, or completely erratic. You may even skip a few months, only to have your period return with a vengeance.

This is because ovulation becomes inconsistent. When you don’t ovulate regularly, your body doesn’t make enough progesterone. Estrogen may still be produced, leading to a state known as estrogen dominance. This can cause mood swings, breast tenderness, and heavier bleeding.

What helps:
Track your cycle with an app or journal. Focus on blood sugar balance, which supports hormone stability.

2. Sleep becomes a challenge

One of the most frustrating things that happen in perimenopause is difficulty sleeping. You may struggle to fall asleep, wake up in the middle of the night, or deal with night sweats that leave you exhausted.

As progesterone drops, so does your body’s ability to stay calm and asleep. Add to that cortisol spikes and blood sugar dips, and restful sleep becomes a nightly battle.

What helps:

• Eat a protein and fibre-rich diet

• Limit caffeine and alcohol

• Add magnesium glycinate before bed

• Keep your bedroom cool and screen-free

A study published in Life (2024) found that lifestyle interventions and CBT for insomnia significantly improved sleep quality in perimenopausal women.

3. You gain weight, especially around the middle

Many women notice that even though their diet and exercise routine hasn’t changed, they start gaining weight, particularly around the belly.

This is not just about age or calories. The hormonal shifts in perimenopause, especially lower estrogen and insulin resistance, make fat storage more likely and weight loss more difficult. Muscle mass also declines, reducing metabolic rate.

What helps:

• Focus on protein at every meal

• Include strength training two to three times a week

• Reduce fast-acting carbohydrates

• Eat earlier in the day to align with your body clock

Building muscle helps improve insulin sensitivity and supports long-term metabolic health. It’s not about shrinking your body, but making it stronger and more resilient.

4. Mood swings and anxiety increase

Perimenopause doesn’t just affect your body. It hits your mood, too. You might feel irritable, anxious, sad, or just emotionally overwhelmed more often than before.

Estrogen plays a role in regulating serotonin and dopamine. When levels fluctuate, your brain chemistry can feel off balance. You may find yourself reacting to small things or feeling flat for no reason.

What helps:

• Don’t skip meals

• Avoid excessive caffeine or sugar

• Include regular movement like walking or yoga

• Add omega-3s from flaxseeds, walnuts, or fish

• Consider adaptogens like ashwagandha or rhodiola with professional guidance

If you’ve had a history of depression or anxiety, this is a good time to speak with your healthcare provider. You are not imagining this.

5. Your skin, gut, and joints change

Dry skin, hair thinning, digestive issues, joint stiffness, these are also things that happen in perimenopause. But they’re often missed or misattributed to stress or lifestyle alone.

Estrogen supports collagen production, gut motility, and even joint lubrication. When levels drop, you may notice bloating, looser stools, or more joint aches than before.

What helps:

• Stay hydrated

• Include good fats like olive oil and seeds

• Eat collagen-rich foods like bone broth or well-cooked lentils

• Use gentle fibre to support digestion, like stewed apple or soaked chia seeds

• Keep movement gentle but consistent

6. Brain fog and forgetfulness creep in

Perimenopause brain is real. You may struggle to find words, forget names, or lose your train of thought mid-sentence. This is not early dementia. It’s the impact of fluctuating estrogen and poor sleep on your working memory.

What helps:

• Prioritise restorative sleep

• Reduce multitasking

• Add choline-rich foods like eggs and cauliflower

• Take breaks from screens and notifications

• Use planners or digital reminders to stay on track

Brain fog improves when hormones stabilise and when inflammation, stress, and blood sugar are well managed.

Your body is not failing you

The things that happen in perimenopause are signs of a biological transition. This phase can feel disorienting, but it’s also a powerful opportunity to reset how you care for yourself.

With the right nutrition, movement, rest, and support, you can move through perimenopause with more clarity, energy, and confidence.