Absorption, or bioavailability, refers to how much of a vitamin makes it from your supplement into your bloodstream. High absorption means you’re actually getting the nutrient you paid for, while poor ...

Caffeine is a natural stimulant. Some studies claim it interferes with the absorption of iron, but research is mixed. In addition to helping you start your day in the morning, consuming caffeine has ...

You’ve been taking iron supplements, eating spinach, and tracking your diet, but the numbers aren’t budging, and your energy is still low. The problem may not be how much iron you’re getting, it’s ...