01/22/2026
"It's okay, I take a supplement to cover potential deficiencies."
But does supplementation really work the same way as nutrients attained from the diet?
This study (and others) suggest that they don't. If vegetarians take in extra iron, they can still be anemic.
Why?
Like most nutrients, it isn't just the nutrient itself. We also need the co-factors that help them do their job appropriately, different forms are sometimes available in our foods than in our supplements and there are absorption issues in some cases as well (our body doesn't extract the full amount that is contained in the supplement).
I'm not picking on vegetarians with this, because we are all susceptible to this.
The takeaway: The Recommended Daily Allowances (RDA's) are designed to keep us from being deficient - not for having us at optimal levels.
If we don't know what is getting into your cells, we are guessing.
Using blood tests to assess these things can be the difference between fatigue, brain fog or sickness and having the vibrant, energetic lives we all crave.