Precision Supplementation
Supplementation is a complex science that requires precision, quality, and personalization. What works for one person may be ineffective or toxic for another.
Bioactive taxonomy
Not all supplements are created equal. We must distinguish survival from optimization.
Essentials (nutritional needs)
Vitamins and minerals to compensate for modern deficits. Depleted soils, industrial food, and sedentary lifestyles create near-universal nutritional needs.
Geroprotectors (longevity)
Molecules that the body doesn't produce or no longer produces enough of, acting on the fundamental mechanisms of cellular aging.
The universal formula myth
The average doesn't exist. What suits one person may not suit another. Your biology is unique — your supplementation must be too.
The U-Curve (hormesis)
Too little is bad, too much is toxic. Only a blood test defines your position on the curve.
Example: vitamin D
Two people taking 2000 IU will have radically different blood levels depending on their genetics (vitamin D receptor), body fat (D3 is fat-soluble), and sun exposure.
Variability factors: VDR genetics, body fat, skin pigmentation, latitude, season.
Scientific evidence: N=1
The Cell study (2015) on personalized glycemic response demonstrated that two people eating the same food can have radically different metabolic responses. Biology is unique. (lien)
Supplementation During Pregnancy
Avoid during pregnancy
Consider adding during pregnancy
- Methylated folate: 600 mcg/day (not synthetic folic acid)
- Vitamin B12 methylcobalamin: 2.5 mcg/day
- Magnesium: 500-600 mg/day
- Iron: 30 mg/day
- Calcium: 1200 mg/day
- DHA/EPA: 1000-2000 mg/day (low heavy metal source)
Consult your doctor before any supplementation during pregnancy.
Possible Luteal Phase Adjustments
- Magnesium: +100-200 mg/day (mood, cramps)
- Sodium: +200-400 mg/day (water retention)
- Potassium: +200-400 mg/day (water retention)
- Ashwagandha: 300-600 mg/day (stress, PMS)
- Rhodiola Rosea: 200-400 mg/day (fatigue, mood)
- Melatonin: 1-3 mg if sleep issues
Vitamin D: the optimal zone for longevity
The official threshold of 30 ng/mL (75 nmol/L) was set to prevent bone disease, not to optimize longevity. Recent data — including the VITAL 2025 trial — point to a higher protective zone, reached through continuous supplementation rather than bolus dosing.
Longevity optimal zone
30 - 60 ng/mL
Range fetched dynamically from the biomarker page. Measure 25(OH)D in late winter to capture the seasonal nadir. View detail page
The VITAL 2025 trial
Across 1,054 participants followed for 4 years, 2,000 IU/day of D3 preserved an average of 140 base pairs of telomeres — equivalent to roughly 3 years of cellular life. Effect documented for daily supplementation, not bolus dosing.
Why no bolus
Bolus doses of 100,000 to 200,000 IU are effective at correcting bone deficiency but ineffective for longevity benefits (immunity, telomeres, metabolism). Pulsatility contradicts the continuous regulation of 25(OH)D — calibrated daily intake outperforms bolus for all extra-skeletal benefits.
Inseparable cofactors
- Magnesium. Cofactor of the hepatic and renal hydroxylases that convert D3 into 25(OH)D and then active 1,25(OH)2D. Supplementing D3 without available magnesium can reveal or worsen a latent magnesium deficit.
- Vitamin K2 (MK-7). 90 to 180 µg/day. Directs calcium activated by D3 toward bones via osteocalcin, and away from arteries via MGP (matrix Gla protein). Indispensable synergy beyond moderate D3 doses.
Individual calibration
1,000 to 2,000 IU/day continuously, adjusted to measured 25(OH)D, BMI (people with obesity absorb 30 to 50% less), skin type, latitude, and season. Oil-based form for optimal absorption, taken with the day's largest fat-containing meal.
Read the full analysis : Vitamin D: the optimal zone for longevity
Interaction chemistry
The stomach is a chemical reactor. Random mixing creates conflicts. The importance of precise timing and ratios is critical.
Antagonisms
Zinc and copper use the same intestinal transporter (MT1). Excess zinc blocks copper absorption. Dosages should therefore be dynamically adjusted based on your blood tests to maintain an optimal ratio. (lien)
An imbalanced ratio creates secondary imbalances.
Synergies
Vitamin D3 + K2
Vitamin D increases calcium absorption, but without vitamin K2, this calcium calcifies arteries instead of strengthening bones. K2 directs calcium to the bones.
Reference table of major interactions
Beyond the two illustrated examples above, these are the antagonistic and synergistic pairs most worth integrating into daily planning.
| Type | Pair | Documented effect | Action |
|---|---|---|---|
| Antagonism | Calcium / Iron | −50 to −60% iron absorption | Separate by 2 h |
| Antagonism | Iron / Polyphenols (tea, coffee) | −60 to −90% absorption | No tea/coffee within 1 h |
| Antagonism | Calcium / Magnesium | Transport competition | Spread across the day |
| Synergy | Vitamin C / Non-heme iron | ×2 to ×6 absorption | Co-administer with meal |
| Synergy | Magnesium / Vitamin B6 | +20% intracellular magnesium | Co-administer in the evening |
| Synergy | Vitamin D / Fatty meal | +50% absorption | Take with the day's fattiest meal |
Read the full analysis : Supplement interactions no one explains
Purity & bioavailability
What's written on the label isn't what reaches your cells. The chemical form determines actual absorption.
The forms deception: magnesium
Why does the industry use oxide? Because it costs 10x less. (lien)
To avoid (industry)
- Titanium dioxide (E171)
- Excessive magnesium stearate
- Talc (E553b)
- Artificial colorings
Ideal standard
- 100% active, 0% filler
- Patented high-absorption forms
- Third-party testing (heavy metals, contaminants)
- Transparent certifications
The feedback loop
A formula is never final. Your needs change, science advances. A static approach quickly becomes obsolete.
Biological adaptation
Your needs constantly evolve. What worked 6 months ago may no longer be optimal today.
Scientific obsolescence
Longevity science advances rapidly. Example: the recent questioning of Resveratrol. What was recommended yesterday may be outdated tomorrow.
What Singular excludes, and why
Three filters systematically rule out certain popular molecules: insufficient real-world bioavailability, lack of convincing human clinical evidence, or unfavorable benefit/risk ratio. A formula's rigor is measured as much by what you take out as by what you put in.
- Resveratrol and stilbenes. Plasma bioavailability below 5 ng/mL in free form despite over 70% intestinal absorption (massive hepatic first-pass). The SIRT1 hypothesis was invalidated in 2010 (peptide-fluorescein artifact). 84 oral administrations analyzed in a 2025 meta-analysis: no robust clinical evidence of longevity benefit in humans.
- Poorly absorbed polyphenols. Quercetin (less than 2% absorbed), EGCG (2 to 13%), fisetin without co-administered formulation. Real plasma concentrations are too low to hit preclinical targets.
- Antioxidants at pharmacological doses. β-carotene: the ATBC and CARET trials showed +18 to +28% lung cancer in supplemented smokers. Vitamin A above 10,000 IU/day: hepatotoxic, increases fracture risk. Vitamin E at 400 IU/day or more: SELECT trial — increased prostate cancer risk. The U-curve applies strictly to fat-soluble vitamins.
- Traditional adaptogens. Ashwagandha and rhodiola: clinical data limited to 4 to 12 weeks, no longevity evidence, with reported hepatotoxic profiles. Reserved for occasional supervised use — never a continuous formula.
- Oral glutathione and orphan precursors. Oral glutathione: degraded in the stomach. Astragaloside IV / TA-65: evidence limited to a single commercial research group. Ergothioneine, apigenin, ALCAR: insufficient bioavailability or human clinical evidence to date.
- CoQ10, ALA, spermidine. CoQ10: mitohormesis suggests that chronic supplementation may inhibit endogenous mitochondrial biogenesis in non-deficient subjects. Alpha-lipoic acid (ALA) and spermidine: converging data missing beyond animal models.