Check your supplement stack in 2 minutes — free, no sign-up. I flag duplicates, ceilings, and the gap you're missing.
Describe your diet, life, and cabinet — get a keep / stop / add report with doses, timing, and an evidence grade on every card.
Check my stack →Instant · 300 combinations"Can you take magnesium with zinc?" A straight verdict for any two supplements — fine together, space them out, or watch the dose.
Look up a combo →30 seconds · Eye-openingTap what you take and see the monthly bill — including the slice going to limited-evidence bottles you may not need.
Add up my shelf →Every check now ends with an honest A–F score — and an anonymous card you can share (or quietly delete).
A multivitamin here, a gummy there, fortified cereal in the morning. Nobody decided to exceed the safe limit — it just adds up. Zinc, iron, B6, and vitamin A are the usual suspects.
Browse upper-limit guides →
If you eat fruit most days, that 1000 mg vitamin C is mostly expensive urine. The question isn't "is it healthy?" — it's "do you need it?" I've watched people stack a multivitamin, a greens powder, and three single-nutrient bottles that all do the same job. Nobody planned it; the shelf just kept growing.
Browse duplicate-stack guides →
Rarely eat fish? Rarely outdoors? Mostly plants? The nutrient you're low on is usually predictable from how you live — and it's often the one bottle not in your cabinet.
Browse symptom guides →70+ supplements — what each is for, the right dose, the safe ceiling, and when to take it. Start with the six most-asked-about.
Short, evidence-graded answers to the pairings and "do I need both?" questions that send people Googling at 11pm.
Vitamin B6 and magnesium are commonly paired in supplements. A clear look at whether B6 actually improves magnesium absorption, what the evidence shows, and how to take them safely.
Read the answer →Calcium needs vitamin D for proper absorption. They are often taken together for bone health, with adults needing 1,000–1,200 mg calcium and 600–800 IU vitamin D daily.
Read the answer →Mostly, but not always. Prebiotics feed existing gut bacteria, while probiotics introduce new strains. A diet rich in prebiotic foods can often make a separate supplement redundant.
Read the answer →A first-person log — what one 35-year-old desk-worker-turned-boxer actually takes, when, and how it feels. Subjective on purpose.
One week of porridge and soup. No training, no supplements, weight down to 79 kg. Restarting today, and thinking about adding iron.
Creatine is clearly doing something. Boxing plus a 5K almost every day is wrecking my mornings, so I'm adding blueberries for the inflammation.
Or read why I built VitaCheck and how the grading works.