Vitamin D3
Vitamin D3 (cholecalciferol) is essential for calcium absorption, immune function, and bone health. Most of the population has insufficient levels, especially in winter.
What is it for?
Indispensable with calcium for absorption and bone health
Key regulator of the immune system
The most universally recommended supplement
For infant bone development and preeclampsia prevention
Breast milk is low in D3. Supplement mother or baby
Prevents accelerated bone loss in pre-menopause
Multiple meta-analyses associate optimal D3 levels with lower incidence of colorectal, breast and prostate cancer.
Optimal levels associated with higher implantation rate
Optimal levels associated with lower all-cause mortality and better immune function with age.
Deficiency causes fatigue
Functions as a prohormone
Very common deficiency in PCOS. Improves insulin sensitivity and fertility
Related to muscle function
Necessary for bone health
Immunomodulator. Deficiency associated with greater severity
Improves muscle function
Deficiency associated with higher body fat
💡 Absorption: Take with a meal containing fat to improve absorption. Combine with vitamin K2 to direct calcium to the bones.
⚠️ Caution: Doses above 4000 IU/day require medical supervision. Monitor blood levels periodically. In those under 18, use only under medical/pediatric supervision.
Recommended doses
Range: 1000 – 4000 UI
Adjust according to blood levels
Range: 4000 – 10000 UI
Under medical supervision
Interactions with other supplements
K2 directs the calcium mobilized by D3 to bones, preventing arterial calcification. Ideal combination.
Magnesium is necessary to activate vitamin D. Magnesium deficiency reduces the efficacy of D3.
D3 increases intestinal calcium absorption by 30-40%. Essential combination for bones.
⚕️ Medication interactions
Corticosteroids reduce vitamin D absorption and accelerate its metabolism, potentially causing deficiency.
→ Monitorizar niveles de vitamina D. Puede ser necesario aumentar la dosis bajo supervisión médica.
🏥 Contraindications
Dosis altas de vitamina D aumentan la absorción de calcio y pueden agravar hipercalcemia.
→ Monitorizar niveles de calcio y vitamina D en sangre.
📚 Scientific references (5)▼
Ficha tecnica oficial del NIH. RDA: 600 UI (15mcg) para adultos 19-70 anos, 800 UI para mayores de 70. UL: 4000 UI/dia.
Revision sobre limites seguros de suplementacion con vitamina D. NIH UL: 4000 UI/dia para adultos. Dosis mayores requieren supervision medica.
Meta-analisis mostrando asociacion entre deficiencia de vitamina D y mayor riesgo de depresion. La suplementacion puede mejorar sintomas depresivos.
Meta-analisis de 81 RCTs. Evidencia robusta para salud osea y prevencion de fracturas cuando se combina con calcio.
Meta-analisis de 25 RCTs (11,321 participantes). La suplementacion con D3 redujo el riesgo de infeccion respiratoria aguda, especialmente en personas con deficiencia.
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