Supplement guide

Zinc

Take with a meal — zinc on an empty stomach commonly causes nausea.

Copper

Take with a meal to reduce stomach upset.

Iron

Best absorbed on an empty stomach in the morning, when the iron-regulating hormone hepcidin is lowest. Take with a small snack if it upsets your stomach.

Calcium

Take with a meal (required for calcium carbonate). Absorption is best at ≤500 mg per dose — split larger amounts.

Magnesium

Evening or bedtime is popular because some people find it relaxing. Consistency matters more than timing.

Selenium

Any time. The margin between enough and too much is narrow — don't stack multiple sources.

Iodine

Any time with or without food.

Potassium

Take with a meal and a full glass of water — potassium tablets can irritate the stomach.

Boron

Any time.

Chromium

Take with a meal.

Vitamin C

Any time. Split large doses — absorption falls above ~1 g per dose.

Vitamin D3

Take with your largest fat-containing meal — fat increases absorption.

Vitamin K2

Take with a fat-containing meal, typically alongside vitamin D3.

Vitamin A

Take with a fat-containing meal.

Vitamin B Complex

Take in the morning with food. Evening doses can feel stimulating or cause vivid dreams for some people.

Vitamin E

Take with a fat-containing meal.

Vitamin B12

Morning is typical. Absorption per dose is limited, so higher oral doses make up for it.

Folate

Any time; often taken with other B vitamins in the morning.

Biotin

Any time. Stop several days before blood tests — high doses distort many lab results.

Vitamin B6

Morning with food. Evening doses may cause vivid dreams.

Omega-3 (Fish Oil)

Take with a meal — reduces fishy burps and improves absorption.

CoQ10

Take with a fat-containing meal. Some people report trouble sleeping when taken late.

NMN

Usually taken in the morning to align with the body's daily NAD⁺ rhythm (a hypothesis, not proven).

Resveratrol

Take with a fat-containing meal (e.g. yogurt or olive oil) — it is poorly water-soluble.

Fisetin

Take with a fat-containing meal. Senolytic protocols often use intermittent high doses — these are experimental.

Curcumin

Take with a fat-containing meal. Plain curcumin is poorly absorbed unless enhanced.

Piperine

Take at the same time as the compound you want to boost (usually curcumin).

Nicotinamide Riboside (NR)

Usually taken in the morning, like NMN.

Quercetin

Take with a fat-containing meal — absorption is poor on its own.

Spermidine

Take with breakfast.

Alpha-Lipoic Acid

Best absorbed on an empty stomach — food lowers blood levels.

PQQ

Morning, with or without food.

Astaxanthin

Take with a fat-containing meal.

Ashwagandha

Evening is common for sleep and stress; take with food if it upsets your stomach.

Rhodiola

Morning — it can be mildly stimulating and disturb sleep if taken late.

Panax Ginseng

Morning with food. Often cycled (a few weeks on, one off).

Bacopa

Take with food to reduce stomach upset. Effects on memory take 8–12 weeks.

Lion's Mane

Any time; morning is common.

L-Theanine

Bedtime for sleep quality, or in the morning with coffee to smooth out caffeine.

NAC

Often taken on an empty stomach; take with food if it causes nausea.

Creatine

Timing barely matters — take it daily. With a meal is convenient.

Glycine

About 3 g before bed for sleep quality.

Taurine

Any time; evening is common because it is calming for some people.

L-Tyrosine

Empty stomach in the morning, or 30–60 min before a demanding task.

5-HTP

Evening. Start low — nausea is common.

Acetyl-L-Carnitine

Morning, often on an empty stomach.

Collagen Peptides

Any time; mix into coffee or a smoothie.

Berberine

With meals, usually split into 2–3 doses to reduce stomach upset.

Milk Thistle

Take with meals.

Green Tea Extract

Always with food — liver injury has mostly been linked to concentrated extracts on an empty stomach.

Ginkgo

Take with meals.

St. John's Wort

With meals. Do not combine with prescription drugs without a pharmacist's review.

Melatonin

30–60 minutes before bed. Low doses (0.3–1 mg) often work as well as high ones.

Probiotics

With a meal. Keep 2+ hours away from antibiotics.

Psyllium Husk

With a full glass of water before a meal. Take other supplements and medications 2 hours apart.

Caffeine

Morning only — caffeine's half-life is ~5 hours, so afternoon doses disturb sleep.