Supplement Stacking: Interactions People Overlook

Taking several supplements together is treated as though effects simply add. They do not, and some of the interactions are meaningful.

Absorption competition

Several minerals compete for the same transport mechanisms. Calcium can interfere with iron and zinc absorption. High-dose zinc affects copper status over time. Iron and zinc taken together reduce each other's uptake. This is why multivitamin formulations containing everything at high doses are not necessarily delivering everything, and why separating certain minerals across the day is a common recommendation.

Medication interactions

This is the higher-risk category. St John's wort induces liver enzymes and reduces the effectiveness of many medications including oral contraceptives and some antidepressants. Vitamin K affects warfarin. Several supplements affect bleeding risk, which matters around surgery. Anything affecting serotonin pathways requires caution alongside serotonergic medication. Grapefruit and some botanicals inhibit enzymes that metabolise a long list of drugs.

Reducing risk

Keep a written list of everything you take, including doses, and show it to your doctor and pharmacist - pharmacists are underused for exactly this and can check interactions quickly. Introduce one product at a time with a gap, so that any adverse effect is attributable. Be particularly careful with multiple products from the same category, since combined doses can be considerably higher than intended when several formulas share ingredients. Fewer products, at known doses, from tested sources, is the sensible default.

If you are considering NeuronGold

Read the NeuronGold ingredients page before ordering, check the 60-day guarantee terms, and if you take prescription medication show the label to a pharmacist — the L-Tryptophan content matters for anyone on serotonergic medication. Our buyer’s checklist sets out twelve checks worth running first.