Expert Answer
What supplements should not be taken together?
Quick Answer
Three pairings come up repeatedly across the panel. Zinc and copper compete for absorption, so a high zinc dose pushes copper down (Hyman). Iron is absorbed at roughly 10% of what you eat, so what sits alongside it matters (Attia). Vitamin D wants about 180 mcg of K2 and some fat with it (Hyman). Magnesium and zinc together are fine.
What Researchers Say
The clearest interaction he names is zinc against copper. High copper reduces zinc absorption and the reverse holds, because the two compete, which is why he uses zinc to correct copper excess rather than stacking both blindly. He pairs vitamin D with K2 in the same capsule.
“typically we want about 180 micrograms of vitamin k2 in a supplement, and there are many vitamin d supplements”
Mark Hyman, on the record @ 02:05:21
Treats iron as the mineral where context decides the outcome. You absorb only a small fraction of what you swallow, which is why he tests before supplementing rather than adding iron to a stack on principle.
“going to consume 10 to 20 milligrams of iron you'll only absorb 10% of that”
Peter Attia, on the record @ 11:04
Takes vitamin K2 as MK-7 for its longer half-life and pairs it with vitamin D rather than running D on its own.
“mk7 has a longer half life, I personally take mk7, I take 50 micrograms a day”
Rhonda Patrick, on the record @ 48:03
Frames the problem as food, not chemistry. Zinc and CoQ10 belong with a meal, B vitamins upset some people on an empty stomach, and a vitamin-mineral supplement works best taken with food early in the day. No number-bearing line of his on this point, so no receipt is shown.
No direct coverage of supplement interactions in the analyzed videos.
Detailed Answer
The short version
Very few supplement pairs are dangerous together. A handful compete for the same absorption pathway, and a few work better together than apart.
Zinc and copper
This is the one the panel returns to. The two minerals use the same absorption route, so pushing one up pulls the other down. Mark Hyman uses that mechanism deliberately: when copper runs high, extra zinc brings it back. The problem comes when someone takes a high zinc dose for months for immune support and never checks copper.
If you take zinc daily at an immune-support dose rather than a food-level dose, the copper question is worth a blood test.
Iron sits on its own
Iron is the mineral most people should not add without testing. Peter Attia's point is about scale: of the 10 to 20 mg you eat in a day, roughly a tenth crosses the gut wall. That absorbed fraction is tightly controlled by your body, which is why iron behaves less like a dial and more like a gate.
Attia tests ferritin before treating anyone's iron, and so does the rest of the panel. Iron is also the supplement where too much is genuinely harmful rather than merely wasted.
Vitamin D wants company
The pairing the panel actively recommends is vitamin D with K2. Hyman puts roughly 180 mcg of K2 in the same capsule as D. Rhonda Patrick takes the MK-7 form at 50 mcg a day for its longer half-life.
Vitamin D is fat-soluble, so it also wants a meal with some fat in it. Taken dry on an empty stomach, less of it gets in.
What is fine together
Magnesium and zinc, taken at ordinary doses, do not meaningfully block each other. Neither does magnesium with vitamin D. Andrew Huberman's practical rule covers most of the rest: take a vitamin-mineral supplement with food, early in the day, and put zinc and CoQ10 with a meal rather than on an empty stomach.
Related Questions
Can you take zinc and magnesium together?
Yes. At ordinary supplement doses they do not block each other, and several of the panel take both. The competition worth watching is zinc against copper, not zinc against magnesium.
Should vitamin D and K2 be taken together?
The panel treats them as a pair. Hyman formulates roughly 180 mcg of K2 alongside vitamin D, and Patrick takes 50 mcg of the MK-7 form daily. Both take D with a meal containing fat.
Is it bad to take iron with other supplements?
Iron is the one to isolate, and more importantly the one to test for first. You absorb only about 10% of dietary iron, and unlike most minerals, excess iron causes real harm rather than being excreted.
Does taking supplements at different times of day help?
For a few of them, yes. Fat-soluble vitamins want a meal with fat, zinc and CoQ10 sit better with food, and anything sedating belongs at night. For the rest, consistency beats timing.
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