How to Take Supplements Together Without Working Against Yourself

Once you're taking more than two or three things, the question stops being what to take and becomes when to take it. Some combinations compete. Some require each other. Most people swallow everything at once with a glass of water and lose a portion of it.

Minerals compete for the same transporters

This is the main one. Divalent minerals — iron, zinc, calcium, magnesium, copper — share absorption routes in the small intestine. Taken together in significant quantities, they compete, and the one present in the largest amount tends to win.

The practical pairs to separate:

• Iron and calcium — calcium markedly reduces iron absorption. Never together.
• Iron and zinc — direct competition at high doses
• Zinc and copper — competing, and sustained high zinc actively increases copper loss (this is why they're formulated at a fixed ratio rather than taken apart)

Magnesium is comparatively relaxed about this and is generally fine alongside most things.

Fat-soluble vitamins need fat

A, D, E and K are absorbed with dietary fat. Taken on an empty stomach with water, absorption is meaningfully reduced.

Take vitamin D, K2 and omega-3 with a meal containing some fat. Not a large meal — a normal one. This is the easiest gain available and the most commonly skipped.

What blocks what

• Tea and coffee contain polyphenols that bind iron. Leave an hour either side.
• Calcium interferes with iron and, at high doses, with zinc and magnesium.
• Zinc on an empty stomach causes nausea in a lot of people. Take it with food.
• Fibre supplements can bind minerals. Space them apart.

A workable schedule

Morning, with breakfast: B vitamins, vitamin D3 + K2, omega-3.
B vitamins are involved in energy-yielding metabolism, and some people find them stimulating; morning is the sensible default. D3, K2 and omega-3 are all fat-soluble and want the meal.

Midday or afternoon, away from tea and coffee: Iron.
Separated from calcium and from your morning coffee. With vitamin C if you have it.

Evening, with food: Magnesium, zinc + copper.
Zinc needs food to be tolerable. Magnesium contributes to normal muscle function and normal psychological function, and evening dosing suits most routines.

Away from the rest: TMG, glutathione.

The rule that matters more than any schedule

A perfect schedule you abandon after ten days is worse than an imperfect one you keep. If splitting across three times of day means you'll stop, take everything at breakfast except iron and accept the loss. Consistency outperforms optimisation by a wide margin.

Check interactions with medication

Vitamin K interacts with warfarin and other anticoagulants. Magnesium and zinc affect the absorption of several antibiotics. Iron interacts with thyroid medication. If you take prescription medicine, check with your pharmacist — this is exactly what they're there for, and it takes two minutes.

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Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Do not exceed the stated dose. Speak to your doctor or pharmacist before starting supplements if you take prescription medication.