Energy supplements: the guide to choosing according to your hormonal profile

Hormones do not only regulate your cycle or your mood: they directly influence energy production at the cellular level. Oestrogens in particular contribute to the proper functioning of mitochondria — the energy powerhouses present in every cell. When their levels fluctuate (luteal phase, postpartum, perimenopause), overall vitality can be affected.

Cortisol, the stress-response hormone, also plays an ambiguous role: in the right quantity, it mobilises the body's resources. In chronic excess, it depletes them. A hormonal imbalance is not always visible in a standard blood test, but it is clearly felt in daily life.

Fragmented sleep and waking too early: the cortisol signal that often goes unnoticed

You fall asleep without difficulty, then open your eyes at 3 or 4 in the morning, your mind already racing. And when you wake up, the tiredness is still there.

Cortisol follows a circadian rhythm: at its lowest in the early part of the night, it rises again in the second half of the night to prepare for waking (Inserm). When the body has been under strain for a long time, this rhythm can lose its balance and trigger an early awakening.

Night after night, a sleep debt builds up. And it is often this debt, more than any single missing nutrient, that keeps the next day's fatigue going.

No supplement can make up for sleep that stays fragmented over time. The fundamentals therefore come first: natural light in the morning, a lighter dinner, eaten earlier, consistent bedtimes, evenings without alcohol or screens.

Once those foundations are in place, micronutrition makes full sense. Magnesium contributes to the normal functioning of the nervous system and to normal psychological function (health claims authorised by EFSA).

If these early awakenings have been going on for several weeks, speak to your doctor.

Female fatigue takes many forms. Here are the most well-documented origins:

• Iron deficiency: menstrual losses regularly expose women of reproductive age to an iron shortfall — often silent but with a very significant impact on energy and concentration.
• Persistently elevated cortisol: professional stress, mental load, emotional overinvestment... a nervous system under constant tension consumes considerable energy resources.
• Deficiencies in key micronutrients: magnesium, vitamins B6 and B12, and vitamin D are often below recommended intake levels, particularly with a depleted modern diet.
• Cyclical hormonal fluctuations: the drop in progesterone and oestrogen during the premenstrual phase or during menstruation generates a very real fatigue that is still too often dismissed.
• A progressively slowing metabolism: after the age of 35–40, the thyroid, the stress-related hormonal system and the production of energy coenzymes can progressively weaken — without pathological thresholds being reached.

A few signals are telling:

• Fatigue that follows the rhythm of your cycle,
• A marked energy dip in the second half of the cycle,
• Persistent morning brain fog,
• Or vitality that has gradually changed after the age of 40.

These signs are worth discussing with your doctor, who can guide appropriate biological investigations. Food supplements do not replace a medical check-up, but they can effectively support the body once the underlying causes have been identified.

Magnesium is involved in more than 300 enzymatic reactions, including the synthesis of ATP — the "energy currency" of your cells. According to dietary consumption data, approximately 70 to 75% of French women do not reach the recommended daily intake. The European Food Safety Authority (EFSA) recognises that magnesium "contributes to the reduction of tiredness and fatigue" and "contributes to normal energy-yielding metabolism". A deficiency often manifests as persistent fatigue, cramps, irritability and sleep disturbances. Favour highly bioavailable forms: magnesium bisglycinate or glycerophosphate.

To make a better-informed choice about your magnesium, you can consult this article: Which magnesium is most effective?

Vitamins B1, B2, B3, B5, B6, B9 and B12 are all involved in normal energy metabolism, according to claims validated by EFSA. They participate in the conversion of carbohydrates, fats and proteins into energy that your cells can use. B6 and B9 additionally play a role in hormonal regulation, while B12 — often deficient in women following a vegetarian diet — is indispensable for the production of red blood cells and for combating fatigue.

Iron participates in the transport of oxygen in the blood via haemoglobin. When it is insufficient, cells are less well oxygenated: fatigue sets in and cognitive performance declines. EFSA confirms that iron "contributes to the reduction of tiredness and fatigue". Before supplementing, a check-up including measurement of your iron reserves (ferritin) is recommended: excess iron is just as harmful as a deficiency. If a deficiency is identified, opt for forms that are well tolerated digestively (iron bisglycinate, for example).

Unlike caffeine, adaptogenic plants support the body's natural capacity to cope with stress and maintain inner balance. Ashwagandha (Withania somnifera) is the best-documented: several clinical studies suggest a positive effect on the perception of fatigue and resilience in the face of stress. Rhodiola rosea is traditionally used to support mental and physical performance in situations of exhaustion. These plants act gently, without creating dependency or causing a rebound effect.

Note: in France, claims about plants do not fall under Regulation EC 1924/2006; the benefits referred to are based on recognised traditional uses and the available clinical data.

Vitamin C "contributes to the reduction of tiredness and fatigue" (EFSA) and improves the absorption of iron from plant sources, making it a valuable ally for women with deficiencies. Coenzyme Q10 (CoQ10) plays a direct role in mitochondrial energy production and tends to decline with age, particularly after 40. Spirulina — a microalgae rich in iron, proteins and B vitamins — is a concentrated source of energising nutrients, provided you choose a certified spirulina that has been tested for the absence of contaminants.

If your fatigue is accompanied by constant tension, mental overactivity in the evening, difficulty falling asleep or night-time waking, this is often the signal of a stress-cortisol axis that is being overworked. The priority approach combines highly absorbable magnesium, B vitamins and adaptogenic plants to support the nervous system and help the body better modulate its stress response.

Have you noticed that your vitality follows the rhythm of your cycle? Marked fatigue in the second half of the cycle, exhausting days after your period, cyclical irritability? These fluctuations are real, and they are not a sign of weakness: your body goes through hormonal variations that directly influence your energy. The idea is to adapt your nutritional support to these phases, rather than adopting a uniform supplementation throughout the month.

If you wake up tired despite a full night's sleep, your energy stays at its lowest in the morning and only really picks up in the late afternoon, this is often the sign of a metabolism running in slow mode. B vitamins, iodine, chromium and certain enzymatic cofactors play a central role here.

After the age of 40, oestrogen production begins to fluctuate in a less predictable way. These variations can affect sleep quality, recovery and energy more markedly than in previous decades. Perimenopausal fatigue is often multifactorial: less restorative nights, greater effort needed to maintain the same performance, vitality that gradually diminishes.

In this context, a medical check-up is particularly useful for ruling out other causes (thyroid, vitamin D deficiency, anaemia). Micronutrition can then provide targeted support. Don't hesitate to speak to your doctor : persistent or long-lasting fatigue is rarely without cause and may point to other underlying conditions.

• Choosing a generic product without targeting your real cause: a "multi-energy" formula may provide nutrients you do not need, at the expense of those you are genuinely lacking.
• Stopping too early: micronutrition takes time. Most actives require 4 to 8 weeks of regular use before a perceptible effect becomes established.
• Accumulating supplements without coherence: some nutrients compete with each other (iron and calcium, for example), while others enhance one another. A targeted approach is always preferable to unsupervised accumulation.
• Neglecting the fundamentals: no food supplement replaces sufficient sleep, a varied diet and regular physical activity. It provides support — not a substitute.
• Ignoring possible drug interactions: if you are following a treatment, always seek the advice of your doctor or pharmacist before starting a supplementation.
• Relying solely on price: the quality of a supplement depends on the form of the actives, their bioavailability, the absence of unnecessary additives and the quality controls carried out — not on its price positioning.