General health supplements: what the evidence says

The world's most popular supplement — with surprisingly little evidence of benefit for well-nourished people.

Shilajit has a handful of small, mostly single-site randomised trials pointing at bone density, collagen synthesis and fatigue resistance, which is interesting but far from established.

An adaptogen with a large Soviet-era literature and almost no modern controlled evidence.

Expensive, heavily marketed, and thinly supported: the one clean meta-analysis found no effect on blood sugar, and the menopause and fertility claims rest on isolated small trials.

Almost every wheatgrass claim — alkalizing the blood, chlorophyll acting like hemoglobin, detoxification — is either biochemically wrong or untested.

There are essentially no human trials of Chondrus crispus for any health claim.

Despite decades of use as a "liver protector," milk thistle has repeatedly failed its best-designed trials: a Cochrane review found no mortality or histology benefit in alcoholic and viral liver disease, and two well-run NASH trials missed their primary endpoints.

TUDCA is a bile acid with genuinely interesting mechanistic biology (ER-stress reduction, bile flow) and almost no confirmatory human outcome data.

Horsetail has a genuine, measurable diuretic effect — one small crossover trial found 900 mg/day matched hydrochlorothiazide 25 mg — but that is essentially the entire human evidence base.

A B-complex reliably corrects B-vitamin deficiency and lowers homocysteine.

Fulvic acid is a mixture of decomposed organic matter from soil or peat, sold with sweeping claims about detox, mineral transport, energy and gut health.

Chemically it is 96-99% sodium chloride, same as table salt, with a pink tint from trace iron oxide.

A cheap, genuine source of B vitamins, protein, beta-glucan and chromium.

The richest natural food source of vitamin E, sold since the 1950s for endurance and fertility on the strength of octacosanol claims that never survived controlled testing.

Greens powders reliably raise blood levels of a few vitamins and carotenoids and can shift oxidative stress markers, but no trial shows they deliver the health outcomes of actually eating fruit and vegetables.

DHM (ampelopsin, from Hovenia dulcis) reversed alcohol intoxication and reduced drinking in rodents, which is why it is sold as a hangover pill — but there is essentially no published human hangover trial.

Freeze-dried liver is a genuinely nutrient-dense food in capsule form — real vitamin A, B12, copper and heme iron — but there are no clinical trials on it, and the same density that makes it appealing makes chronic high-dose use a preformed-vitamin-A and copper risk.

Shark cartilage is one of the clearest debunks in the supplement world: the premise that sharks don't get cancer is false, and two well-run randomized trials — including a 379-patient phase III — found no survival or quality-of-life benefit whatsoever.

Rehmannia glutinosa is a foundational "kidney yin" herb in Chinese medicine and is almost never studied alone — the human evidence is for multi-herb formulas like Rehmannia-6 (Liu Wei Di Huang Wan), where results are modest and the herb's individual contribution is unknown.

Neem has real antimicrobial activity and the best human data are for neem mouthrinse in gingivitis, where small trials put it roughly on par with chlorhexidine.

Sarsaparilla is a root sold as a "blood purifier" and testosterone booster with essentially zero controlled human evidence for either.

Heavily marketed as a natural cancer treatment on the basis of cell-culture data, graviola has never been tested for cancer in a human trial — and its signature compounds are the leading suspect in an epidemic of atypical parkinsonism in Guadeloupe.

Noni juice is among the most aggressively marketed cure-all supplements and among the least supported: after decades of sales there is still no adequately powered trial showing benefit for any condition, and there is a documented signal for idiosyncratic liver injury.

Clove oil is a legitimate topical dental analgesic thanks to its eugenol content, and that is where its evidence begins and ends.

Myrrh has a defensible niche as a topical antiseptic mouth rinse and essentially nothing else: the one time a myrrh drug was tested head-to-head as an antiparasitic, it failed badly.

One small Iranian trial found burdock root tea lowered inflammatory and oxidative markers in knee osteoarthritis, but it never reported pain or function.

The 'stone breaker' does not break stones.

NADH is sold for fatigue and "cellular energy" on the strength of a handful of small chronic fatigue trials, most of which used it in combination with CoQ10.

This is one of the most dangerous categories on the shelf: independent testing found most over-the-counter thyroid supplements contain actual thyroid hormone, at doses capable of causing thyrotoxicosis.

The liver detoxifies continuously without help, and no randomized trial has shown that a detox or cleanse product removes any specific toxin from a human being.

Liquid chlorophyll went viral for clear skin, deodorizing and weight loss — none of which has decent human trial support.

Zeolite (clinoptilolite) is a volcanic aluminosilicate sold as a heavy-metal detox binder, but no human trial has shown it removes heavy metals from people.

Modified citrus pectin is a depolymerized pectin that binds galectin-3, and single-arm trials in biochemically relapsed prostate cancer show PSA doubling-time changes worth further study.

C15:0 is an odd-chain saturated fat from dairy that shows up in blood as a marker of dairy intake and correlates with lower diabetes risk in cohort studies.

Laetrile is not a vitamin and does not treat cancer.

Hemp seed oil is a decent culinary oil with a favorable omega-6 to omega-3 ratio and some gamma-linolenic acid, but it contains no CBD and no EPA or DHA.

Bee pollen is a genuinely nutrient-dense food — protein, flavonoids, carotenoids — but human trials are tiny, mostly uncontrolled, and confined to niche endpoints like menopausal hot flushes.

Schuessler cell salts are twelve mineral compounds sold in homeopathic 6X dilutions, which deliver micrograms of mineral per tablet — thousands of times below any nutritionally relevant dose.

Corydalis yanhusuo is a genuinely interesting analgesic herb: its alkaloids act on dopamine receptors and produce real pain relief in animal models without opioid tolerance.

Marketed as an "estrogen detox" and hormone-clearance aid based on a real biochemical mechanism — beta-glucuronidase inhibition — that has only ever been demonstrated in rodents.

Young barley leaf powder is a legitimately nutrient-dense green with well-characterised antioxidant flavonoids, but human clinical trials are almost nonexistent and the "alkalising" and "detox" claims behind its marketing are physiologically unfounded.

An old "blood purifier" and green-food tablet whose only respectable human data — an LDL reduction — came from eating around 120 g of alfalfa seeds a day, not from tablets.

An essential amino acid and the precursor of histamine and carnosine.

The sulfur amino acid that limits glutathione synthesis.

An essential amino acid central to methylation.

An essential amino acid used heavily by the gut to make mucin.

A largely saturated fat sold as a health food.

A traditional diuretic and urinary herb.

A culinary herb with a long history as a diuretic.

The staple of heavy-metal detox protocols.

A traditional lymphatic and urinary herb.

A European herb used to flush the urinary tract, approved for that traditional use by German regulators.

The silky styles of maize, used traditionally as a soothing diuretic for bladder irritation.

A South African leaf long used for urinary complaints.

A traditional herb for fevers, wounds and bleeding.

A bitter root traditionally used as a gentle laxative and a tonic for iron.

A mint-family herb used in Germany for mild overactive thyroid symptoms.

An iodine-rich brown seaweed sold for thyroid support.

A wild-harvested cyanobacterium from Klamath Lake sold as a "superfood".

Cultured micro-algae (usually Tetraselmis chuii or Nannochloropsis) sold for energy and recovery.

Powdered whole green tea leaf, so you swallow the leaf rather than an infusion.

A Nordic berry rich in polyphenols and, like cranberry, in proanthocyanidins.

An Ayurvedic herb (Boerhavia diffusa) used traditionally as a diuretic and kidney tonic.

One of the three fruits in triphala, promoted for cholesterol and respiratory health.

A Himalayan bitter root used in Ayurveda for the liver.

A traditional Chinese "yin tonic" root used for dry cough and dry throat.

A rare Taiwanese fungus (Antrodia cinnamomea) grown commercially as mycelium and sold for liver support and hangovers.

Freeze-dried liver, heart, kidney and spleen in capsules, sold on the idea that eating an organ supports the same organ in you.

An intermediate of the Krebs cycle sold for energy, endurance and hangovers.

Blends of chlorella, cilantro and "binders" such as zeolite or modified citrus pectin, sold on the premise that most people carry a hidden metal burden.

A genuine chelating agent, sold in capsules for "metal detox" and artery cleaning.

Capsules and shots combining dihydromyricetin, N-acetylcysteine, electrolytes, B vitamins and herbal extracts.

Blends built around ginkgo biloba and zinc, sometimes with B12 or magnesium.

Herbal blends — typically uva ursi, nettle, dandelion, parsley and cranberry — marketed for kidney and urinary health.

B vitamins plus adaptogens such as rhodiola, ginseng or ashwagandha, sold for daily energy.

Instant coffee blended with lion's mane, chaga, reishi or cordyceps extracts.

Encapsulated dried juice powders sold as insurance against a poor diet.

Drink mixes of beet, berry and pomegranate powders sold for antioxidant support and circulation.

Ginger plus vitamin B6 capsules for travel nausea.

Activated charcoal, bentonite and zeolite blends sold to remove mycotoxins from the body.

Multi-herb protocols built on Japanese knotweed, cat's claw, cryptolepis and andrographis, sold for persistent Lyme symptoms.

A classical Ayurvedic multi-herb tablet (Bauhinia variegata bark plus guggul resin) sold for thyroid nodules and lymph swelling.

A six-herb Chinese formula used for centuries as a kidney-yin tonic.

The hardened saliva nest of swiftlets, one of the most expensive traditional tonics in Asia, sold for skin, immunity and cognition.

Solomon's seal rhizome, a Chinese tonic used for fatigue and dryness, rich in polysaccharides and steroidal saponins.

Fish oil in kid-sized doses, gummies or flavoured liquids, marketed for brain and eye development.

Blends built around pumpkin seed extract, sometimes with soy germ, hops or sumac, sold for urgency and night-time urination.

Mixed products combining CoQ10, xylitol and oral probiotics for gums and cavities.