Fatigue in perimenopause: why it really happens and how to get your energy back

Before going any further, one important clarification: perimenopause is different from menopause. It is more precisely the phase that precedes it, sometimes by several years, during which the ovaries produce fewer and fewer hormones, and in an irregular way. In other words: cycles become disrupted, symptoms appear, but periods are still present.

Perimenopause (or premenopause) begins on average around the age of 45, sometimes as early as 40 or before, and lasts between 4 and 8 years, sometimes up to 10 years[1]. This transitional nature is often a source of confusion. Indeed, many women do not make the connection between their persistent fatigue and this hormonal change, because they do not yet know they are going through it.

Fatigue is one of the most common and most debilitating symptoms of this period. It is multifactorial, which explains why it so often resists the usual solutions (sleeping more, resting more). To truly address it, we first need to understand what is driving it.

1. Falling hormone levels profoundly disrupt sleep

Oestrogen and progesterone do not only regulate the menstrual cycle, period. They also directly affect sleep quality. Progesterone in particular has a natural sedative effect on the central nervous system. Its decline causes a form of hyperarousal that makes it harder to fall asleep and sleep less deep[2].

Oestrogen also contributes to melatonin production and serotonin regulation. When its levels fluctuate or decline, the circadian rhythm is disrupted. This generally results in fragmented nights, early waking and less restorative sleep than before! This is therefore not insomnia in the classic sense of the term, but “hormonal insomnia”, the causes of which are multifactorial.

2. Night sweats disrupt recovery cycles

Hot flushes do not only occur during the day. At night, they interrupt deep sleep phases. As a reminder, these are the periods during which your body regenerates its cells, consolidates your memory and replenishes its energy reserves. Waking at 2am followed by intense heat, heavy sweating, then cooling down, is a disruption to the recovery cycle your body needs.

Even if you do not always remember them in the morning, these micro-awakenings build up and explain why you can sleep through the night and wake up exhausted.

3. Magnesium deficiency plays an amplifying role

Perimenopause is a period of increased physiological stress. Yet stress uses up magnesium. This mineral is essential for more than 300 enzymatic reactions in the body, including cellular energy production and regulation of the nervous system[3].

Magnesium deficiency is relatively common among women aged 40-50, often without them knowing it. Its manifestations? Persistent fatigue, irritability, muscle tension, difficulty unwinding in the evening or night cramps. These symptoms overlap with those of perimenopause and may therefore go unnoticed.

Pauline’s opinion, Dietitian Nutritionist

“What we understand better today is that perimenopause puts the body under strain — a real, physiological strain. And this strain comes at a cost: it draws on magnesium reserves. Yet magnesium is one of those discreet but absolutely fundamental minerals. Without it, hundreds of mechanisms in the body slow down — energy production, the balance of the nervous system, sleep quality.

The problem is that magnesium deficiency is not immediately visible. It develops gradually, and its signs — fatigue that drags on, diffuse irritability, muscles that struggle to relax, cramps that wake you at night — are exactly like what many women experience around their forties. Everything is attributed to perimenopause, which is understandable. But a simple, practical, and often very effective nutritional avenue is sometimes overlooked.“

4. Loss of muscle mass reduces cellular energy reserves

From your forties onwards, muscle mass gradually declines; a natural phenomenon known as sarcopenia, which falling oestrogen levels accelerate during perimenopause. Here, the issue is not aesthetic. Muscle is metabolically active tissue: it is where a large part of energy synthesis takes place via the mitochondria.

Less muscle also means fewer functional mitochondria, and therefore a reduced capacity to convert nutrients into available energy. Creatine plays a key role here: it directly fuels the ATP resynthesis cycle, the cell’s “energy currency”. Studies conducted in adults over 60 show documented benefits for muscle mass and cognition, findings increasingly extrapolated to women in perimenopause, for whom sarcopenia accelerates early[4].

5. Mental and emotional overload are characteristic of this period

Perimenopause often comes at a pivotal time in women’s lives: children growing up or leaving home, ageing parents and professional responsibilities on the rise. Added to this life context are the direct effects of hormonal decline on mood: increased anxiety, mood swings, lower self-confidence, cognitive fog… The resulting mental fatigue is real and perfectly measurable. 

Both regulated by oestrogen, dopamine and serotonin govern motivation, mood and resilience to stress. Their dysregulation can cause a lack of drive, mild anhedonia and mental fatigue that make everyday efforts particularly demanding[5].

A fresh perspective on nutrition

Certain dietary choices can directly help support energy production in perimenopause.

Among them, we can mention:

• Protein: often under-consumed by women, yet essential for maintaining muscle mass and synthesising neurotransmitters. Aiming for at least 1.2 g per kilogram of body weight per day is a reasonable benchmark from the age of 45.
• Foods rich in magnesium: almonds, pumpkin seeds, legumes, 70% dark chocolate, spinach — these foods can help address a deficiency that has often been present for years.
• Complex carbohydrates (oats, brown rice, sweet potato): they help maintain stable blood sugar levels and prevent post-meal energy slumps. Conversely, rapid sugar spikes followed by blood sugar crashes are major drains on energy.
• Limit caffeine after 2 pm and alcohol in the evening: both fragment sleep and amplify nocturnal hot flushes.

Moving differently

Physical activity remains one of the most powerful tools against fatigue in perimenopause, provided you avoid falling into the trap of overdoing it. A body that is already tired does not need daily HIIT sessions. What it needs most is regular, varied, and restorative movement.

For example, brisk walking, swimming, yoga, and Pilates can help support overall energy levels, stress management, and sleep quality.

Light to moderate strength training (2 to 3 sessions per week) contributes to preserving muscle mass, stimulating the mitochondria, and supporting cellular energy over the long term. This is where creatine can play a useful supporting role.

Prioritising good sleep hygiene

In perimenopause, taking care of your sleep is essential. Here are a few practical adjustments that can make a real difference:

• A cool bedroom (18 to 19°C) and lightweight nightwear in natural fabrics
• A regular bedtime and wake-up time, even at weekends
• No screens in the hour before bed
• An evening wind-down ritual: a warm bath, reading, slow breathing
• Avoid heavy meals after 8 pm

For night sweats, natural solutions such as common sage may help reduce the frequency and intensity of heat episodes.

Because diet and lifestyle are not always enough to make up for what perimenopause depletes, targeted supplementation can make a real difference — provided it is chosen wisely. At Jolly Mama, several products specifically address the mechanisms of fatigue in perimenopause, and they work in a complementary way!

Péri Essentials: the foundational support

Designed specifically for perimenopause, Péri Essentials combines 17 vitamins and minerals, plus bacopa Bacognize®, which has benefits for memory, mood, attention, concentration, emotional balance, stress and sleep quality.

It is the "foundation" supplement — the one that supports overall balance when everything is fluctuating, so that the rest (sleep, physical energy, mental clarity) can gradually recalibrate.

Créatine Mama: the cellular fuel

Contrary to what one might think, creatine is not reserved for the gym. Creatine is a compound naturally produced by the body from amino acids. Its role is to recycle ATP, faster than the body would manage on its own[6]. Muscles and the brain benefit from it directly.

In perimenopause, Créatine Mama addresses two concrete needs: preserving the muscle mass that falling oestrogen levels erode (without bulking up!) and supporting mental clarity when cognitive fog sets in. It can be combined with Péri Essentials for a fully synergistic effect.

Magnesium bisglycinate: the nervous system and muscle rebalancer

Jolly Mama's magnesium bisglycinate is a highly bioavailable form, meaning it is efficiently absorbed by the body, without the unpleasant digestive effects that other forms of magnesium can cause[7].

Its action is twofold in perimenopause. On one hand, it nourishes the nervous system: less tension, less mental overactivation in the evening, and a more natural onset of sleep. On the other hand, it supports muscle function. This means fewer cramps, lighter recovery, and a feeling of a less "heavy" body.

Particularly relevant in the evening, bisglycinate directly counteracts one of the most common vicious cycles of this period: stress -> magnesium deficit -> poor sleep -> fatigue -> increased stress.

Can these three supplements be combined?

Perfectly complementary, Péri Essentials, Créatine Mama and magnesium bisglycinate work on three distinct levels: overall nutritional support (Péri Essentials), the nervous system and recovery (magnesium), and cellular and muscular energy (Créatine Mama). For women going through deep, multifactorial fatigue, this combination covers all their needs.

The fact that fatigue is a common symptom in perimenopause does not mean it should be ignored. Certain signs deserve particular attention:

• Intense, persistent fatigue that does not improve after several weeks of lifestyle adjustments.
• Fatigue accompanied by unexplained weight gain, excessive sensitivity to cold, or constipation, which may point towards hypothyroidism.
• Difficulty sleeping despite a normal duration of sleep, which may indicate restless legs syndrome or sleep apnoea (underdiagnosed in women).
• Fatigue associated with pallor, palpitations, or unusual shortness of breath, which may suggest anaemia.

A simple blood test, including a full blood count, TSH, ferritin, vitamin D, and red blood cell magnesium, can most often rule out quickly correctable causes. Do not wait for this fatigue to become debilitating before speaking to your GP or gynaecologist.