Vitamin D supplementation improves health and looks
Real benefit IF you are deficient. Most populations are. Aim for serum 25-OH-D 40-60 ng/mL. Test, don't guess. No incremental benefit past sufficient.
What the evidence says
The studies, decoded
Hossein-nezhad 2013, Holick 2017 reviews: vitamin D deficiency (<20 ng/mL) is prevalent in 30-50% of Western populations. Supplementation in deficient adults improves mood (Spedding 2014 meta-analysis), bone mineral density, and modestly reduces all-cause mortality (Bjelakovic 2014 Cochrane review — small but significant effect in deficient subgroups). For looksmaxxing specifically: vitamin D status correlates with skin healing, mood, and serum testosterone in deficient men.
How it actually works
Mechanism
Vitamin D is a steroid hormone, not just a 'vitamin'. Receptors on most cell types. Modulates calcium absorption, immune function, mood-related neurotransmission, and steroidogenesis.
What to actually expect
Realistic outcome
Test serum 25-OH-D before supplementing (cheap, $25-40 lab test). Target 40-60 ng/mL. Most deficient adults need 2000-5000 IU/day; some need more. Take with fat for absorption. Pair with K2 (MK-7 100-200 mcg) to direct calcium to bone, not arteries.
If this is overhyped — what is not
Better alternatives
Measured sun exposure (15-20 min midday, arms and face) produces 1000-3000 IU naturally. Fatty fish, egg yolks, fortified dairy. Tanning beds — no (see tanmaxxing page).
Sources
Citations
- Vitamin D deficiency — global epidemicHolick, 2017, Rev Endocr Metab Disord
- Vitamin D and depression — meta-analysisSpedding, 2014, Nutrients
Ashwagandha reduces stress and boosts testosterone
Cortisol reduction signal is real for chronically stressed adults. Testosterone bump is small (~15%) and only documented in specific populations. Liver toxicity reports are real at high doses.
WorksCreatine monohydrate builds strength, muscle and cognition
Most-studied supplement that exists. Real strength + hypertrophy + cognitive gains, especially in vegetarians. Cheap, safe, no loading phase needed.
CopeBiotin gummies / 'hair vitamins' regrow hair
Biotin deficiency is real — almost nobody has it. For deficient users, supplementation restores hair growth; for everyone else, it's a $20/month placebo with a real risk of interfering with lab tests.