We know navigating the world of supplements can feel overwhelming. With so many options out there, it’s hard to know what works and what doesn't.
While most vitamins and nutrients are safe, some combinations can cancel each other out, or worse, overload the same pathways. Others, when combined intentionally, can significantly amplify your results.
Here’s what to pair, what to space out, and why it matters.
Power Pairs:
Vitamin D3 + Vitamin K2
Why it works: D3 improves calcium absorption, K2 directs calcium to your bones, not your arteries.
The science: Heightened K2 intake to reduced arterial calcification and coronary heart disease
Vitamin C + Iron
Why it works: Vitamin C transforms iron into a more soluble form.
The science: Vitamin C can double iron absorption. et al. (1981) showed iron absorption from plant meals was significantly increased when taken with 50–100mg of Vitamin C.
Space these out:
Iron + Calcium
Why to avoid: They compete for the same absorption channels.
Best practice: Take at least 2 hours apart.
Zinc + Copper
Why to avoid: Too much zinc can cause copper deficiency.
Best practice: Only take both when dosed intentionally and ideally in balanced ratios.
How ingredients interact is just as important as what’s in the bottle. Smart combinations amplify results; poor pairings can diminish them.
Further Reading:
Schwalfenberg, G.K. (2017). Vitamin K2: Essential for Prevention of Chronic Disease. Nutrients.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452218/
Gast, G.C. et al. (2009). Journal of Nutrition.
https://academic.oup.com/jn/article/139/10/1833/4670773
Hallberg L. et al. (1989). Am J Clin Nutr.
Cook J.D. et al. (1981). Am J Clin Nutr.
https://academic.oup.com/ajcn/article/34/4/587/4692142
Visioli F. et al. (2009). Olive Polyphenols and Mitochondrial Function. Br J Nutr.
Trammell SAJ et al. (2016). Nature Communications.
https://www.nature.com/articles/ncomms12948
Kennedy DO et al. (2010). Effects of B Vitamins on Cognitive Performance. Psychopharmacology.
Hallberg, L. et al. (1991). Iron, Calcium and Absorption. Am J Clin Nutr.
Turnlund, J.R. et al. (1990). Long-term high zinc intake and copper status. Am J Clin Nutr.