Buying it well
Don't get
fleeced.
The supplement aisle is barely regulated and the medication market is deliberately opaque, and both are full of ways to overpay for the wrong thing. This is how to buy the right version of each entry — the spec, the quality marks that matter, and the legitimate places to get it. We sell nothing, link to no seller, and take no affiliate cut. That's the point.
Why supplements are a minefield
Here's the fact that reframes everything: the FDA does not approve dietary supplements. Under the 1994 DSHEA law, makers are responsible for their own products' safety, and the agency only steps in after something goes wrong. No one checks, before it hits the shelf, that the bottle contains what the label claims.
That gap is exactly what third-party testing fills. And it matters, because independent testing keeps finding the gap is real: a 2023 JAMA analysis of melatonin gummies found 22 of 25 were inaccurately labeled — actual melatonin ran from 74% to 347% of the stated dose, and one had none at all. The lesson isn't "supplements are poison." It's that the label alone is not evidence, and a third-party mark is how you close the distance.
The five signals that matter
Ignore the marketing and check these, in order:
- The right form and dose. Half of buying well is buying the correct thing — magnesium glycinate not oxide, creatine monohydrate not a fancy ester, fish oil measured by EPA+DHA not total oil. Each entry's panel names the spec.
- Third-party tested. An NSF, USP, or Informed mark means someone independent confirmed the contents. Without it, you're trusting the label — which the data says you shouldn't.
- Price per effective dose. Not per pill or per serving. A "premium" form at 8× the price of the one with the evidence is a worse buy, not a better one.
- Single-ingredient, no proprietary blends. A "blend" can legally list only its total weight, hiding whether the active ingredient is present at a real dose. It usually isn't.
- A certificate of analysis (CoA). The best brands publish a lot-specific lab report showing identity, actual potency with a number, and contaminant limits (heavy metals, microbes). A seal offered instead of a CoA is a weaker signal than the CoA itself.
The certifications, compared
Not all seals mean the same thing. From strongest assurance to "legal floor":
| Mark | Run by | What it verifies | Best for |
|---|---|---|---|
| NSF Certified for Sport | NSF | Label accuracy, contaminant limits, and screening for ~290 substances banned in sport. Ongoing lot monitoring. | Athletes and anyone drug-tested — the gold standard for banned-substance assurance. |
| USP Verified | U.S. Pharmacopeia | Contains what the label says at the stated potency, no harmful contaminants, made under GMP, and dissolves for absorption. Annual surveillance. | General quality — the strongest mark for identity, potency, and purity. |
| Informed Sport / Choice | LGC | Banned-substance and contaminant testing. Informed Sport tests every batch; Informed Choice samples monthly (lighter). | Athletes — per-batch (Sport) is the most rigorous; Choice is a step down. |
| ConsumerLab | Independent (subscription) | Buys products at retail and publishes pass/fail reviews. A watchdog service, not a seal a brand pays to display. | Comparing brands before you buy — independent, but behind a paywall. |
| cGMP | FDA (mandatory) | Manufacturing process and consistency — not that the product was tested, approved, or is accurately dosed. | Nothing extra. It's the legal floor every supplement must meet, not a quality signal. |
Red flags
- Proprietary blends. They hide the per-ingredient dose. Assume the marketed ingredient is under-dosed.
- "Clinically proven" with no citation. A slogan, not evidence, unless it links to a study on that product and dose.
- Mega-doses past the upper limit. More is not better and can be harmful. Check the tolerable upper intake level.
- Amazon-only no-name brands. No traceable maker, no seal, no CoA — the classic vector for mislabeled or contaminated product.
- The spiked categories. Weight loss, "test boosters," sexual enhancement, and pre-workout are where the FDA's tainted-products database finds hidden pharmaceuticals. Treat those shelves with real suspicion.
Buying prescriptions well
For medications the problem flips. Quality isn't the worry — these are FDA-approved and dispensed by licensed pharmacies. Price is the worry, and the system is built to obscure it. Two moves fix most of it:
1. For cheap generics, shop the cash price. Most of our Rx entries — statins, metformin, ezetimibe — are generics that cost a few dollars a month if you look. Mark Cuban's Cost Plus Drugs posts a transparent cost-plus-15% price; GoodRx coupons, Amazon Pharmacy's RxPass, Costco (no membership needed for the pharmacy), and $4 generic lists all compete. The cash price with a coupon often beats your insurance copay — compare both every time, and ask for a 90-day supply.
2. For branded drugs, the lever is coverage. PCSK9 inhibitors, SGLT2s, and GLP-1s are expensive; insurance with a prior authorization (your clinician's office files it) plus manufacturer savings cards is the real path.
On GLP-1s specifically: the legitimate route is a prescription filled at a licensed pharmacy. The FDA declared the semaglutide and tirzepatide shortages resolved in 2025 and the compounding grace periods have closed, so mass-marketed "compounded semaglutide" now largely falls outside the legal exception. If a clinician prescribes a compounded formulation, insist on a state-licensed or accredited pharmacy. Never use overseas or "research-use" sellers — for any drug.
The buying index
Every entry we've written a buying guide for, at a glance. Open any one for the full spec, look-for/avoid, and legitimate vendors.
| Item | Section | Buy as | Typical price | |
|---|---|---|---|---|
| Protein | OTC | Whole-food protein first; a plain whey, casein, or (for plant-based) pea/soy isolate powder to fill the gap — bought by grams of protein per serving. | ~$0.50–1.20 per 25 g serving | → |
| Blood pressure | OTC | a validated upper-arm oscillometric monitor | ~$40–80 for a validated home upper-arm monitor | → |
| A1c & glucose | OTC | a standard glucometer, or an OTC continuous glucose monitor if you want trends | glucometer ~$10–30 plus ~$0.15–0.50 per test strip; OTC CGM ~$50+/month of sensors | → |
| Caffeine | OTC | Coffee or tea for everyday use (cheapest by far); caffeine pills or gum only when you need precise, portable dosing. | ~$0.02–0.10 per 100 mg as pills; coffee varies | → |
| Creatine | OTC | Plain creatine monohydrate powder — ideally Creapure-labeled (the German-made reference material). | ~$0.10–0.25 per 5 g | → |
| Psyllium | OTC | Plain psyllium husk (generic Metamucil-equivalent) — the unflavored, unsweetened powder or capsules. | ~$0.05–0.20 per serving | → |
| Iron | OTC | A ferrous salt (ferrous sulfate, gluconate, or bisglycinate) — but only AFTER a ferritin test confirms you're low. | ~$0.05–0.20 per tablet | → |
| Melatonin | OTC | A low-dose melatonin (0.3–1 mg) — the physiological range, which is genuinely hard to find on shelves dominated by 3–10 mg. | ~$0.05–0.20 per dose | → |
| Vitamin B12 | OTC | Plain B12 — cyanocobalamin (cheapest and stable) or methylcobalamin — only after confirming a deficiency. | ~$0.03–0.10 per tablet | → |
| Omega-3 | OTC | A fish (or algal) oil dosed by its COMBINED EPA+DHA content — not the total fish-oil milligrams on the front. | ~$0.20–0.60 per gram of EPA+DHA | → |
| Vitamin D | OTC | Vitamin D3 (cholecalciferol) softgels, dosed to your tested need — commonly 1000–2000 IU. | ~$0.02–0.08 per softgel | → |
| Ashwagandha | OTC | A standardized root extract — KSM-66 or Sensoril, the two forms most of the trials actually used. | ~$0.15–0.40 per serving | → |
| Magnesium | OTC | Magnesium glycinate (bisglycinate) for an evening sleep trial — check the ELEMENTAL magnesium per serving, not the compound weight. | ~$0.10–0.30 per serving | → |
| Zinc | OTC | A modest elemental-zinc dose (e.g. 15–30 mg) in an absorbable form — or zinc acetate/gluconate lozenges for a cold. Check ELEMENTAL zinc, not compound weight. | ~$0.03–0.15 per serving | → |
| Berberine | OTC | Standardized berberine HCl, single-ingredient, with the berberine content stated per capsule. | ~$0.20–0.50 per day | → |
| Curcumin | OTC | A bioavailability-enhanced curcumin — a phytosome/lipid form (e.g. Meriva) or a piperine-paired product. Plain turmeric powder is barely absorbed. | ~$0.20–0.60 per day | → |
| Glycine | OTC | Plain glycine powder — a single-ingredient amino acid, faintly sweet, that costs almost nothing. | ~$0.03–0.10 per 3 g | → |
| L-theanine | OTC | L-theanine, ideally the Suntheanine branded form (the patented, pure L-isomer used in most of the research). | ~$0.10–0.25 per 200 mg | → |
| Statins | Rx · pharmacy | atorvastatin or rosuvastatin (generic) | ~$3–7 per 30-day supply cash; often under $15 for a 90-day supply | → |
| GLP-1 (semaglutide) | Rx · pharmacy | brand semaglutide (Wegovy/Ozempic) or tirzepatide (Zepbound/Mounjaro), by prescription | — | → |
| SGLT2 inhibitors | Rx · pharmacy | empagliflozin (Jardiance), dapagliflozin (Farxiga), or canagliflozin (Invokana) — branded, prescription only | — | → |
| PCSK9 inhibitors | Rx · pharmacy | evolocumab (Repatha) or alirocumab (Praluent) — branded injectables, prescription only | — | → |
| Ezetimibe | Rx · pharmacy | ezetimibe (generic; the brand is Zetia) | ~$4–15 per 30-day supply cash; well under the brand's list price | → |
| Metformin | Rx · pharmacy | metformin (generic; immediate-release or extended-release/ER) | ~$4–10 per 30-day supply cash; frequently on $4 generic lists | → |
| Tadalafil | Rx · pharmacy | tadalafil (generic; for daily use, the 2.5 mg or 5 mg tablet) | ~$0.20–1.00 per daily tablet cash via price-transparency services | → |
| Testosterone (TRT) | Clinician | prescription testosterone (generic gel, cream, or injectable) — only after a diagnosis of hypogonadism | — | → |
| Low-dose aspirin | OTC | low-dose aspirin, 81 mg (generic; store brand is fine) | ~$0.01–0.03 per tablet; a year's supply is a few dollars | → |
| Enclomiphene | Clinician | enclomiphene citrate (compounded only; no FDA-approved product exists) | — | → |
| LDN | Rx · pharmacy | low-dose naltrexone (compounded; typically 1.5 mg, 3 mg, or 4.5 mg capsules) | ~$1–2 per capsule from a compounding pharmacy (roughly $30–60/month) | → |