Why Your Vitamin D Is Still Low (Even If You Take Supplements)
Vitamin D deficiency is common. Many people take supplements daily. Yet their lab results remain low. Understanding Vitamin D Levels Vitamin D status is measured by 25-hydroxyvitamin D, written as 25(OH)D. Optimal range: 40–60 ng/mL. Insufficiency: 20–30 ng/mL. Deficiency: below 20 ng/mL. Even if you take 2,000 IU daily, levels may stay under 30 ng/mL. Factors beyond dosage affect absorption and activation. 1. Dose May Be Too Low Most adults require 4,000–5,000 IU daily for optimal levels. Obese individuals (BMI > 30) store vitamin D in fat tissue, reducing circulation. People with darker skin need higher doses due to melanin blocking UVB absorption. 2. Timing and Fat Intake Matter Vitamin D is fat-soluble. It needs dietary fat to be absorbed efficiently. Taking supplements on an empty stomach can reduce absorption by up to 50%. Take with meals containing healthy fats like avocado, eggs, or olive oil. 3. Magnesium Deficiency Blocks Activation Magnesium c...