6 min. read
Cellular longevity · Journal
At 35, 45 or 55, the body is not in decline. It is in transition. Precise physiological mechanisms follow one another, predictable and adjustable. Understanding them means taking back control of your energy, your body composition and your longevity.
From the age of 35, testosterone production gradually decreases, at a rate of around 1 to 2% per year. This phenomenon, known as partial andropause or age-related androgen deficiency, is subtle at first, and that is precisely what makes it hard to identify. There is no sudden switch as with the menopause, but a gradual drift that affects several systems at once.
The early signs are often wrongly put down to work fatigue or “stress”: persistent low energy, reduced muscle strength, a build-up of abdominal fat, less restorative sleep, lower libido, and sometimes a slight shift in mood towards irritability or disengagement. These signs are linked to the fall in the androgen signal, not to a lack of willpower or to inevitable ageing.
Testosterone is not only a sex hormone. It is involved in body composition (the muscle to fat ratio), bone density, red blood cell production, mental clarity and mood through the dopaminergic pathways. Its decline therefore has systemic consequences, well beyond the sexual sphere.
What speeds up the drift can largely be identified: chronic stress (cortisol inhibits testosterone production), lack of sleep (70% of testosterone is produced during deep sleep), vitamin D deficiency (VDR receptors are present in the Leydig cells, which produce testosterone) and zinc deficiency (an enzyme cofactor of steroidogenesis). All of these are levers you can act on directly.
Scientific reference
Investigation, treatment and monitoring of late-onset hypogonadism in males
These recommendations, co-signed by several learned societies of andrology and urology, describe how to diagnose, treat and monitor age-related hypogonadism in men. Diagnosis is based both on symptoms and on a blood test of testosterone, interpreted by a doctor.
“Testosterone is not just a sex hormone. It is a hormone of body composition, cognitive vitality and musculoskeletal longevity.”
Male ageing is not confined to a single area. It is a network of interconnected mechanisms that influence each other in a cascade. Acting on one pillar improves the others, and neglecting one of them weakens the whole.
Nutritional needs change with age, and “normal” laboratory markers do not always reflect an optimal state. A 45-year-old man can have normal standard blood tests and still have functional shortfalls that hold back his performance, his recovery and his hormonal balance.
| Nutrient | Documented mechanism |
|---|---|
| L-Citrulline → NO | L-Citrulline is converted into L-Arginine in the kidneys, then into nitric oxide (NO) in the vascular endothelium. NO is a natural vasodilator described in the literature as involved in muscle blood flow, blood pressure regulation and the blood supply to erectile tissue. The bioavailability of L-Citrulline is higher than that of L-Arginine taken directly. Energy Daily Flow provides 1,000 mg per stick. |
| Vitamin D3 → bones, muscles, immunity | Vitamin D is a steroid hormone whose receptors (VDR) are present in the Leydig cells of the testes, in muscle, in the brain and in bone. Studies report a positive correlation between 25(OH)D levels and free testosterone. Vitamin D contributes to the maintenance of normal bones, to the maintenance of normal muscle function and to the normal function of the immune system. At 3,000 IU/day, the oil-based formula of D3 Active+ is designed for optimal absorption, a key point for this fat-soluble nutrient. |
| Magnesium → fatigue, muscles, nervous system | Magnesium is a cofactor for more than 300 enzyme systems, including those involved in testosterone synthesis. The literature also describes a reduction in SHBG (sex hormone binding globulin), which increases the bioavailable free testosterone fraction. Magnesium contributes to a reduction of tiredness and fatigue, to the normal functioning of the nervous system and to the maintenance of normal muscle function. Bisglycinate is the best tolerated and best absorbed form, with no laxative effect at usual doses. |
| Zinc → normal testosterone & defences | Zinc is the enzyme cofactor of 5-alpha-reductase (the conversion of testosterone into DHT) and of the steroidogenesis enzymes. A zinc deficiency leads to a measurable fall in serum testosterone. Zinc contributes to the maintenance of normal testosterone levels in the blood and to the protection of cells from oxidative stress: two claims authorised in Europe. Heavy sweating (sport, heatwaves) increases zinc losses: active men have needs above the standard NRVs. |
| Setria® glutathione & antioxidants | Glutathione is the main antioxidant inside cells. The body's own production declines with age and chronic stress. Setria® is a form of reduced glutathione (GSH) whose oral bioavailability has been clinically validated, unlike standard oxidised glutathione. The authors describe protection of the Leydig cells against oxidative stress, preserving their ability to produce testosterone. |
| Melatonin → circadian rhythm | Melatonin synchronises the body clock and prepares the neuroendocrine conditions for the night-time testosterone peak. Melatonin contributes to the reduction of time taken to fall asleep (a claim authorised from 1 mg per dose). A melatonin shortfall (blue light, jet lag, chronic insomnia) desynchronises the hypothalamic-pituitary axis and reduces the night-time LH signal that stimulates testosterone production in the testes. |
“A 45-year-old man is not old: he stands at the crossroads of two paths, one of passive decline and one of active longevity. Targeted nutrition means choosing the second.”
The BIOLOGYST men's protocol targets the four mechanisms of active ageing at the same time: hormonal capital, cardiovascular health, sleep quality and antioxidant protection. Five formulas cover the whole spectrum, with no overlap and with a documented logic of synergy.
Composition: L-citrulline 1,000 mg · Taurine 500 mg · Beta-alanine 500 mg · Setria® GSH 250 mg · Ginseng 60 mg · Magnesium, zinc, vitamins C, D3 and B (including B9 Quatrefolic®), 1 stick per day.
Role in the protocol: NO production and vasodilation, mitochondrial energy, endurance and muscle recovery, mental clarity. Vitamin C contributes to the reduction of tiredness and fatigue and to the protection of cells from oxidative stress; vitamin B9 contributes to the normal functioning of the nervous system.
Composition: bisglycinate + citrate + ATA Mg® · 300 mg of magnesium in total · more than 300 enzyme systems involved.
Role in the protocol: free testosterone (via SHBG, a mechanism described in the literature), normal muscle function, stress resistance, sleep quality. Magnesium contributes to a reduction of tiredness and fatigue and to the normal functioning of the nervous system.
Composition: vitamin D3 (cholecalciferol) 3,000 IU · 75 µg · oil-based formula.
Role in the protocol: support for the androgen axis via VDR receptors, bone mineralisation, immunity, muscle function. Vitamin D contributes to the maintenance of normal bones, to the maintenance of normal muscle function and to the normal function of the immune system.
Composition: per 3 capsules, quercetin 427.5 mg · Setria® glutathione 375 mg · ExceptionHYAL® Star 240 mg · vitamin C 150 mg.
Role in the protocol: protection of the Leydig cells against oxidative stress, mitochondrial support, limiting age-related cellular oxidative stress. Vitamin C contributes to the protection of cells from oxidative stress.
Discover Antioxidant Defense →
Composition: melatonin 1.8 mg · valerian · passionflower · California poppy · marjoram.
Role in the protocol: circadian synchronisation, preparation of the night-time testosterone peak, neuroendocrine recovery. Melatonin contributes to the reduction of time taken to fall asleep.
Morning (before or during breakfast). 1 stick of Energy Daily Flow + 1 D3 Active+ softgel with some fat, for optimal absorption. This is the best time for daytime energy and hormonal support.
Evening meal. 1 stick of Magnesium Active+ in a glass of water and 2 to 3 capsules of Antioxidant Defense. Magnesium supports neuromuscular relaxation in the evening; the antioxidants support the night-time cellular repair that begins during sleep.
Before bed (20 to 30 min). 5 sprays of Deep Sleep under the tongue. Melatonin contributes to the reduction of time taken to fall asleep. Valerian and passionflower are plants traditionally associated with bedtime, with no authorised health claim to date.
Course length. 2 to 3 months minimum to observe effects on body composition and energy.
Food supplements are no substitute for a healthy lifestyle. They are amplifiers: they increase the return on every healthy habit and make up for shortfalls linked to the modern environment. But certain non-negotiable basics determine how well they work.
“Ageing well as a man is not about keeping the look of your 30s. It is about optimising your energy, clarity and vitality for the decades to come.”
Discover the BIOLOGYST men's protocol
Precautions. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Do not exceed the recommended daily dose. Keep out of the reach of children. If you are undergoing treatment, have persistent symptoms or have any doubt about your profile, consult a healthcare professional.
Testosterone production decreases from around 35, at a rate of 1 to 2% per year. This age-related androgen deficiency is gradual, with no sudden switch, which makes it hard to identify at first.
Yes: 70% of testosterone is produced during deep sleep. Fragmented sleep or sleep of less than 6 hours reduces the night-time androgen peak by 15 to 20%, and the rise in cortisol the next day further inhibits production.
Zinc contributes to the maintenance of normal testosterone levels in the blood: this is the claim authorised in Europe on this subject. Vitamin D, magnesium and sleep quality are the other adjustable cofactors identified in the literature.
Allow a 2 to 3 month course. Effects vary from one person to another and do not replace a suitable lifestyle.
Five formulas cover the four pillars: Energy Daily Flow (NO and energy), Magnesium Active+, D3 Active+, Antioxidant Defense and Deep Sleep. More analyses are available in the BIOLOGYST Journal.
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