vitamin8 cited usesBest taken: morning

Vitamin D

Cholecalciferol, the most bioavailable form of vitamin D. Essential for calcium absorption, bone health, immune function, and mood regulation. Synthesized in the skin upon sun exposure.

What it’s good for

Low MoodStrong

Vitamin D receptors are expressed throughout the brain, including mood-regulating regions. Vitamin D modulates serotonin synthesis via tryptophan hydroxylase-2 activation and influences BDNF expression, neuroplasticity, and HPA axis regulation.

Dose: 2000–4000 IU

Vitamin D receptors are present in skeletal muscle mitochondria. Vitamin D supports mitochondrial function, reduces inflammatory cytokines (IL-6, TNF-alpha) that drive fatigue, and modulates neuromuscular function for energy production.

Dose: 2000–4000 IU

Vitamin D activates innate immune defenses by inducing cathelicidin and defensin antimicrobial peptides. It also enhances macrophage pathogen killing, modulates T-cell response, and reduces excessive inflammatory cytokine production.

Dose: 2000–4000 IU

Vitamin D modulates both innate and adaptive immune responses required for recovery. It supports macrophage antimicrobial function, reduces excessive inflammation, and promotes tissue repair through growth factor regulation.

Dose: 2000–4000 IU

Vitamin D regulates calcium metabolism in articular cartilage, supports chondrocyte function, and modulates immune-mediated inflammatory processes in joints. Deficiency is associated with increased OA progression and pain severity.

Dose: 2000–4000 IU

Back PainStrong

Vitamin D deficiency causes osteomalacia and musculoskeletal pain. Vitamin D receptors in paraspinal muscles and spinal structures mediate anti-inflammatory effects, and supplementation reduces chronic low back pain in deficient individuals.

Dose: 2000–4000 IU

Vitamin D modulates both innate and adaptive immune responses, shifting the balance from pro-inflammatory Th1/Th17 to anti-inflammatory Th2/Treg responses. It suppresses NF-kB, reduces TNF-alpha, IL-6, and CRP, and enhances anti-inflammatory IL-10.

Dose: 2000–4000 IU

Vitamin D receptors (VDR) are highly expressed in hair follicle keratinocytes and are essential for hair follicle cycling, particularly the anagen (growth) phase initiation. Deficiency is associated with alopecia areata and telogen effluvium.

Dose: 2000–4000 IU

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