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Add your supplements, doses and timing to reveal synergies, conflicts, redundancies and an optimised daily schedule.
The global supplement industry generates over $150 billion annually, but most people taking supplements do so without understanding how individual compounds interact when combined. Some interactions are synergistic: vitamin D3 and vitamin K2 are synergistic partners because D3 increases absorption of calcium while K2 directs it into bone rather than arterial walls. Magnesium is required as a cofactor for vitamin D activation, meaning supplementing D3 without adequate magnesium may be less effective than the dose alone would suggest. Zinc and copper compete for the same intestinal absorption pathway, so supplementing high-dose zinc without copper risks copper deficiency over time.
Other interactions are antagonistic or create redundancy. Taking both fish oil (omega-3) and a separate EPA supplement is redundant — the body cannot distinguish the source. High-dose alpha-lipoic acid can chelate minerals including zinc and biotin, creating deficiencies if taken long-term without co-supplementation. Fat-soluble vitamins (A, D, E, K) accumulate in tissue rather than being excreted in urine, making excessive doses of any single fat-soluble nutrient a real toxicity risk — particularly vitamin A, where chronic intakes above 3,000 mcg RAE per day from supplements are associated with bone loss and liver damage in large cohort studies.
Supplement timing affects both efficacy and tolerability. Fat-soluble compounds (vitamins A, D, E, K, CoQ10, omega-3 fatty acids, and curcumin) are absorbed significantly better when taken with a meal containing dietary fat — studies show up to 30–60% greater absorption with food compared to fasted administration. Water-soluble compounds like vitamin C, B vitamins, and most amino acids can be taken with or without food, though high doses of vitamin C (1,000 mg+) are better tolerated when divided across multiple doses to avoid gastrointestinal symptoms from osmotic effects in the gut. Magnesium glycinate, threonate, or malate are better tolerated than magnesium oxide or citrate in people prone to loose stools at therapeutic doses.
Certain supplements are best timed around sleep. Magnesium glycinate and L-theanine taken 30–60 minutes before bed have demonstrated sleep quality improvements in randomised trials and are logically timed to their effects on GABA receptors and parasympathetic tone. Melatonin is best taken 30–60 minutes before intended sleep time, at the lowest effective dose (0.5–1 mg) rather than the 5–10 mg doses common on store shelves, which exceed physiological levels and can blunt natural melatonin secretion over time. This analyzer identifies these timing considerations for your specific combination.
Not all supplements marketed for longevity are created equal. The strongest human evidence exists for compounds like vitamin D (deficiency correction reduces cardiovascular and autoimmune risk), omega-3 fatty acids (EPA specifically reduces triglycerides and cardiovascular events at 4g/day in the REDUCE-IT trial), and creatine (maintains muscle mass and cognitive performance with strong safety data across decades). NMN and NR (NAD+ precursors) have demonstrated NAD+ elevation in human trials but human longevity outcome data remain limited. Resveratrol's bioavailability in standard forms is so low that the animal study doses cannot be replicated in humans without specialised formulations. This analyzer scores supplements by evidence tier to help you prioritise spending on compounds with the strongest human clinical backing for your specific goals.
Go Deeper
NMN, resveratrol, spermidine, CoQ10, rapamycin — what the clinical evidence actually shows and how to build a stack that makes sense.
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