Advance Physician Formulas
a nutritional supplement company founded in 2003
Supplement Research Update by Ray Sahelian, M.D.
One of my passions as a medical doctor and nutrition expert is to self-experiment with vitamins, herbs, teas, and all sorts of dietary supplements. I learn from these trials and it helps me understand the published research in a more complete way.
Question: Can you explain to me the term "herbal extract." How does one know the potency of an extract and whether it is good or not. Also what does that mean when it says on the label a 4:1 extract or a 10:1 extract?