Supplement Interactions
What Competes
Which pairings genuinely interact, the mechanism behind each, and how strong the evidence really is.
Most supplement interaction content presents every pairing at the same level of confidence, which is how you end up with an internet where everything interacts with everything and none of it helps you decide. Every page here carries an evidence tier: well documented, human clinical evidence, human evidence limited, mechanism only, or commonly claimed with weak evidence. The tier is the point. It tells you how much weight the finding can carry before you read a word of it.
Minerals that compete
Minerals share absorption pathways, so taking one at a high dose for a long time in isolation is the pattern that causes problems.
Well documented. Sustained high-dose zinc without copper is a known cause of copper deficiency.
철분과 칼슘Human clinical evidence. Real in a single meal, much smaller across a whole diet.
철분과 아연Human clinical evidence. A ratio question, and mostly absent once the minerals arrive in food.
마그네슘과 칼슘Commonly claimed, weak evidence. The 2 to 1 ratio is not what people think it is.
Pairings that help
Not every interaction is a warning. Some combinations are the reason a nutrient works at all.
Human clinical evidence. The one pairing here where together is the goal.
비타민 D와 K2Human clinical evidence. Where the calcium goes once vitamin D has helped you absorb it.
비타민 D와 마그네슘Human clinical evidence. The enzymes handling vitamin D are magnesium dependent.
셀레늄과 갑상선Well documented. A meta-analysis of 35 studies, and a mineral with a real ceiling.
카페인과 L-테아닌Human clinical evidence. The pairing behind the calm-focus effect people chase.
Worth asking your prescriber about
Compounds active enough to help are active enough to interact. That is not an argument against them, it is an argument for your prescriber knowing.
Human clinical evidence. Overlapping pathways, plus a documented effect on drug-clearing enzymes.
칼슘과 갑상선약Well documented. A four-hour spacing question that is easy to get wrong.
오메가 3와 항응고제Human evidence limited. More nuanced than the warnings suggest, and real where it is real.
프로바이오틱스와 항진균제Mechanism only. A timing rule that rests on reasoning rather than trials.
When the supplement changes the test
One entry, because it is the interaction people are least likely to suspect and most likely to be harmed by.
No page here sells the supplement it is warning about. Where a real caution exists it is stated plainly, and where a widely repeated interaction turns out to rest on very little, that is stated just as plainly.
14 pages published so far. More are being added.
Know what interacts with what
Occasional notes on the pairings worth knowing about, the mechanisms behind them, and how strong the evidence actually is.