VEXTA Lab
Evidence-based longevity, in plain English
Dosages, safety data and clinical trial results — every figure traced to a published study. Our full catalogue and shop are in French.
Summer Body Longevity Stack 2026: French RCT-Validated Protocol (NMN, Urolithin A, Magtein)
How to prepare your body for summer 2026 with a science-based 8-week longevity protocol. French GMP manufacturing, brand-name actives (Magtein, Mitopure, AstaReal), HPLC public COAs. Glow up, lose abdominal fat, restore energy.
Astaxanthin dosage: 8 mg or 12 mg per day? What the EFSA assessment actually says
The astaxanthin dose EFSA assessed as safe in food supplements, where the widely quoted 12 mg figure comes from, and why the two numbers answer different questions.
Astaxanthin and the thyroid: what the published research actually shows
Many pages claim astaxanthin supports thyroid function. A search of the biomedical literature returns no human study — and a single publication, carried out in zebrafish larvae.
Astaxanthin and the sun: does it help you tan, and does it actually protect?
What the randomised trial Ito 2018 measured on UV-exposed skin, at what dose and in how many participants — and why astaxanthin is never a substitute for sunscreen.
Spermidine: what dose, and why your blood levels don't rise
The first pharmacokinetic study of oral spermidine shows plasma spermidine does not increase — spermine does. What that changes for dosing and for what can honestly be claimed.
Spermidine and hair: what the randomised trial actually measured
A randomised, double-blind trial in 100 people over 90 days measured the effect of a spermidine-based supplement on the anagen phase of hair follicles. Results, method and limitations.
Quercetin and allergy: what the research shows, and what it was done on
The meta-analysis of quercetin's anti-allergic effects covers animal models. The only human trial available uses a 200 mg phytosome form. Why that distinction changes everything.
Quercetin: dosage, bioavailability, and why the form matters more than the milligrams
Why comparing two quercetin products by milligram count misleads, what form and dose human trials actually use, and how to read a label.
PQQ: what dose, what regulatory status, and for whom
The PQQ dose EFSA assessed for food supplements, how it compares with natural dietary intake, which populations are explicitly excluded, and what the safety data covers.
Oral glutathione: why the liposomal form changes everything (and what the trials really show)
A randomised trial of plain oral glutathione found no effect at all. A pilot study of the liposomal form reports substantial increases. A comparison of methods, doses and limitations.
NMN: how much per day, when to take it, and for how long?
The NMN doses tested in human clinical trials, timing, how long before anything is measurable, and the regulatory picture. Based on the Yi 2023 RCT (GeroScience, n=80, 60 days).
Urolithin A: what dose, for how long, and what the trial actually measured
The urolithin A doses tested in clinical trials, the duration of published studies, what the ATLAS trial measured — including the missed primary endpoint — and why natural production concerns only a minority of people.
Magnesium L-threonate: what dose, when, and what the two trials really show
The magnesium L-threonate dose used in clinical trials, how much elemental magnesium it actually delivers, results from Liu 2016 and Lopresti 2025 on cognition and sleep, and how it sits against the 250 mg safety limit.