Supplement timing — why when matters as much as what
Nutrient transporters are regulated by circadian clocks. The same supplement absorbed at different times of day delivers measurably different results.
lifestyle
Cell membranes maintain a voltage differential — the membrane potential — driven by ion gradients of and Nutrient transporters are often electrogenic, meaning the electrical state of the membrane directly affects how efficiently nutrients cross it. Circadian biology regulates transporter expression in intestinal epithelial cells across the day. Cortisol from stress alters tight junction integrity and ion channel behaviour in real time. Nutrition is applied electrochemistry.
Fat-soluble vitamins — A, D, E, K1, K2 — require dietary fat present for absorption and are best taken with the largest fat-containing meal, typically breakfast or dinner. Vitamin D taken late in the day may interfere with melatonin production via pineal gland receptors — morning is preferable. B vitamins support energy metabolism and align with the cortisol-driven activation of morning. taken in the evening supports sleep.
Morning with fat: Vitamin D, A, E, K1, K2, B-complex, CoQ10, iodine
With any meal: (first dose), (separated from and coffee)
Evening: (second dose), fat-soluble vitamins if missed at breakfast
Before bed: glycine (3g — clinical support for sleep onset and quality), ashwagandha
Never combine: and and in large doses; fat-soluble vitamins with high-fibre meals