What we wish we'd known before our first $60 supplement spree. No affiliate-ranked nonsense.
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New to supplements? Start here.
B1 to B12 in plain English — what each B vitamin does, the 'B vitamins for energy' myth, the one with a real toxicity ceiling (B6), and the specific groups who genuinely benefit from a B-complex versus those who don't.
Starter 11 min· updated 6/29/2026
Fat-soluble vitamins with a meal, magnesium in the evening, iron on an empty stomach with vitamin C, and the pairs you should NOT take together. A practical, evidence-based timing guide.
Starter 7 min· updated 6/28/2026
Most people get enough from food. The ones who actually benefit from supplementing are heavy sweaters, low-carb/keto eaters, and people in heat. What each electrolyte does, smart dosing, and the potassium safety catch.
Starter 6 min· updated 6/28/2026
What the evidence actually shows — forms, dosing, and myths.
An honest, evidence-hedged look at whether biotin (vitamin B7) helps hair and nails, the important lab-test safety warning, and the real cost per dose.
Science 6 min· updated 7/6/2026
An honest, data-backed guide to creatine for women — the studied form, the ~3-5 g dose, the "will it make me bulky" question, and real cost per dose.
Science 6 min· updated 7/6/2026
An honest, hedged look at creatine monohydrate side effects — water weight, GI upset, and the kidney myth — using only what the research generally supports.
Science 6 min· updated 7/6/2026
A practical guide to buying vegan vitamin B12 — why most B12 is already vegan, cyanocobalamin vs methylcobalamin, and the real cost per dose.
Science 6 min· updated 7/6/2026
An honest, data-informed guide to creatine timing — why consistency and total daily dose matter far more than the exact hour you take it.
Science 6 min· updated 7/6/2026
Is berberine really "nature's Ozempic"? An honest look at what the evidence shows, the risks, and berberine's cost per dose from 17 tracked listings.
Science 7 min· updated 7/4/2026
An honest look at what collagen supplements may do for skin and joints, plus the real cost per gram across 61 tracked listings — median $0.47/serving.
Science 7 min· updated 7/4/2026
Folate vs folic acid vs methylfolate compared: forms, cost per dose, and an honest look at MTHFR. What most people actually need, plus pregnancy notes.
Science 7 min· updated 7/4/2026
A cost-per-dose companion supplement stack for GLP-1 users (Ozempic/Mounjaro): protein, vitamin D, magnesium, B12, omega-3 — and the full daily cost.
Science 7 min· updated 7/4/2026
A hedged, evidence-minded look at testosterone supplements: why most "T-booster" blends underdeliver, and the cheap deficiency-correction approach.
Science 7 min· updated 7/4/2026
The AREDS2 eye formula is real science — but it was studied for slowing one specific eye disease, not for keeping healthy eyes sharp or fixing screen fatigue. Here's what the trial found, the exact ingredients and doses, and how little the components actually cost per dose.
Science 8 min· updated 7/3/2026
B12 only comes from animal foods, so vegans, people over 50, and anyone on metformin or acid-reducing drugs are most at risk. Here are the symptoms (some can become permanent), the right tests, and how to correct it — oral, sublingual, or injection.
Science 10 min· updated 6/29/2026
Vitamin D deficiency is common and often silent. Here's who's most at risk, the one blood test that settles it (25-OH-D), what the numbers mean, and how to correct a low level without overdoing a fat-soluble vitamin.
Science 10 min· updated 6/29/2026
D3 and D2 are not interchangeable. D3 raises and holds your blood vitamin D more effectively per dose, while D2 — the common US prescription form — is less efficient. Here's the evidence, the sourcing, and what vegans should know.
Science 8 min· updated 6/29/2026
Most ashwagandha trials use a standardized root extract at a specific dose — so the branded extract and the milligrams matter more than the brand. The honest buyer's guide, plus who shouldn't take it.
Science 6 min· updated 6/28/2026
Ubiquinol is the body-ready form and absorbs somewhat better — but a well-made oil-based ubiquinone works fine for most younger people at a lower price. Dose, the statin question, and how to take it so it absorbs.
Science 6 min· updated 6/28/2026
Magnesium won't knock you out like a sedative, but correcting a shortfall can genuinely help sleep and relaxation. Glycinate is the form to reach for — here's the dose, timing, and honest expectations.
Science 6 min· updated 6/28/2026
Water-soluble vitamins you flush out; fat-soluble vitamins and minerals accumulate and have real ceilings. The NIH upper limits worth knowing — vitamin A, D, iron, zinc, B6, selenium — and why megadoses backfire.
Science 7 min· updated 6/28/2026
Plain turmeric powder barely gets into your blood. The dose that matters is curcumin — and whether it's paired with black pepper or a lipid/phytosome delivery. How to read the label so you don't buy expensive excretion.
Science 6 min· updated 6/28/2026
D3 helps you absorb calcium; K2 is thought to steer that calcium into bone instead of arteries. Here's what the evidence actually supports, sensible doses, and the one group who must check with a doctor first.
Science 6 min· updated 6/28/2026
The internet says methyl-B12 is the only 'natural' form and cyano is toxic. The evidence is more boring: both work for most people. Here's when the form genuinely matters.
Science 6 min· updated 6/11/2026
Plain ascorbic acid works fine and costs pennies. Liposomal and buffered C solve specific problems — at 5–10x the price. When the upgrade is worth it and when it is marketing.
Science 6 min· updated 6/11/2026
Official RDAs are floors, not optima. Here's the practical dosing range, when to take it, and why D3 + K2 is usually a smarter buy than D3 alone.
Science 6 min· updated 5/14/2026
Picolinate vs gluconate vs sulfate, the copper-balance gotcha, and why long-term high-dose zinc is a bad idea.
Science 6 min· updated 5/8/2026
Bisglycinate calms; citrate is gentler on the wallet but bumps the GI dose ceiling. The case-by-case decision tree.
Science 7 min· updated 4/22/2026
Buy smart: cost per dose, value traps, and what to skip.
Whether a daily multivitamin is worth it, what's actually inside one, when a single targeted supplement beats a multi, and how to compare real cost per serving instead of sticker price.
Shopping 7 min· updated 7/9/2026
A prenatal buyer's guide grounded in NIH figures: which nutrients matter (folate, iron, iodine, DHA, choline, vitamin D), why the cheapest bottle isn't always complete, and how to compare real cost per serving.
Shopping 8 min· updated 7/9/2026
Why some people choose a low- or no-iron prenatal, why most pregnancies still need iron, how to read the label, and how to compare cost per serving without fooling yourself.
Shopping 5 min· updated 7/9/2026
Creatine monohydrate is the value and evidence winner. Compare cost per gram across 29 tracked listings and why "advanced" forms cost more.
Shopping 7 min· updated 7/4/2026
Learn how to compare protein powder by cost per gram of actual protein — not per tub or scoop — with a worked example and real VitaminDB price data.
Shopping 7 min· updated 7/4/2026
We tracked 3,331 supplements across 113 nutrients. For the same nutrient at a similar dose, cost per serving can vary thousands of times. Here's why.
Shopping 7 min· updated 7/4/2026
Protein, fibre, electrolytes and a few key vitamins are the supplements most often paired with GLP-1 medications. Review sites list a price and a dose but never divide the two — so here's the same list ranked the only way that tells you what you're really paying: cost per dose.
Shopping 7 min· updated 7/3/2026
Vitamin D is the deficiency most often reported in people on GLP-1 medications — one 2026 review found about 14% were deficient at a year. It's also one of the cheapest supplements per dose. Here's the why, the sensible numbers, and the cost per 1,000 IU.
Shopping 6 min· updated 7/3/2026
Krill oil is marketed as the premium omega-3 — and it's often priced like it, several times more per gram of EPA + DHA. Once you count the actual omega-3s delivered per dollar, plain fish oil usually wins on value by a wide margin.
Shopping 6 min· updated 7/2/2026
Chelated magnesium, bisglycinate iron, ubiquinol CoQ10, picolinate zinc — the upgraded forms often cost several times more per dose for a real-but-modest benefit that matters for some people and is pure marketing for others. When to pay up and when to skip it.
Shopping 7 min· updated 7/2/2026
Supplements are not FDA-approved before sale, so third-party seals are the main independent check on what's actually in the bottle. Here's what USP, NSF, NSF Certified for Sport, Informed Sport and Informed Choice each test — and why 'GMP certified' is not the same thing.
Shopping 7 min· updated 7/2/2026
The sticker price on the bottle is the wrong number. Cost per dose — price ÷ servings ÷ active amount — is what you actually pay each day, and the same dose can cost many times more just depending on the brand.
Shopping 6 min· updated 7/2/2026
Carbonate is cheaper per milligram but needs a full meal and stomach acid to work. Citrate costs more and absorbs anytime. The buy-decision broken down by who you are.
Shopping 6 min· updated 6/11/2026
Ferrous sulfate is cheap and effective but wrecks a lot of stomachs. Bisglycinate and slow-release cost more and treat people gently. How to actually absorb iron without the misery.
Shopping 6 min· updated 6/11/2026
The 1000 mg on the front of the bottle is not the dose that matters. Here's how to find the actual EPA + DHA content and what daily target makes sense.
Shopping 5 min· updated 5/3/2026
Why a $3 bottle of magnesium oxide is mostly a laxative, and what to buy if you actually want the muscle and sleep effects.
Shopping 5 min· updated 4/29/2026