I Built a Vitamin D Calculator — Here's Why 1000 IU Is Wrong for Most People

I Built a Vitamin D Calculator — Here's Why 1000 IU Is Wrong for Most People Everyone takes vitamin D. Everyone recommends different doses. But how much do YOU actually need? I built a Vitamin D Calculator at Botánica Andina that factors in your age, skin type, and location to give you a personalized recommendation. The results surprised me. The Problem: One Size Doesn't Fit All The FDA says 400 IU/day. Many doctors say 1000-2000 IU. Some supplements come in 5000 IU doses. Why the wild variation? Because vitamin D needs depend on: Where you live (latitude, sun intensity) Your skin type (melanin blocks UVB) Your age (skin produces less as you age) Time spent outdoors A 60-year-old in Santiago, Chile with dark skin needs dramatically more than a 20-year-old in Bogotá with light skin. How the Calculator Works Inputs: Age - affects skin synthesis efficiency Skin type (Fitzpatrick scale) - affects UVB penetration Location in LATAM - calculates sun angle/UV index Time outdoors - baseline sun