The pantry
27 kitchen remedies, graded
Each food and herb is shelved by the strength of the human evidence for its best-supported use. Open a jar for every claim graded one by one, the amounts studied, who should avoid it and its drug interactions.
Strong Consistent trials
Several good randomized trials or a high-quality meta-analysis agree, in people like the reader, at amounts people actually use.
- GrapefruitCitrus x paradisiInteracts with many medicines. A healthy fruit with one serious catch: it changes how the body handles certain medicines. It is the best-documented food-drug interaction there is. The fat-burning claims are not supported.
- OatsAvena sativaLDL cholesterol. One of the best-supported foods in this whole reference: the soluble fiber in oats, beta-glucan, lowers LDL cholesterol a little but reliably.
- PsylliumPlantago ovata (seed husk)Chronic constipation. The seed husk sold as a bulk fiber. It has the best evidence of any fiber supplement for chronic constipation and a solid record on LDL cholesterol.
- Yogurt and kefirDigesting lactose. Cultured milks with the clearest evidence of any fermented food: their live bacteria help digest lactose. Other claims rest on probiotic supplement trials or observational data.
Moderate Promising, with caveats
Randomized trials point the same way, but they are small, short, or mixed in quality, so the size of the effect is uncertain.
- Apple cider vinegarAcetic acid from fermented apple juiceBlood sugar after a meal. Taken with a starchy meal, vinegar modestly lowers the blood sugar spike that follows. The weight-loss claims rest on small, uneven trials, and the acid has real downsides.
- CranberryVaccinium macrocarponFewer repeat UTIs in women with recurrent infections. The one berry with a large body of trials behind it. Cranberry products cut repeat urinary infections in some groups of people, but they are not a treatment for an infection you already have.
- FlaxseedLinum usitatissimumSlightly lower blood pressure. A seed rich in fiber, lignans and the plant omega-3 ALA. Trials show a small drop in blood pressure; milling it matters if you want the omega-3.
- GarlicAllium sativumBlood pressure in people with hypertension. Garlic supplements have shown small drops in blood pressure in people with hypertension. The cholesterol and cold evidence is weaker, and supplements can interact with some drugs.
- GingerZingiber officinaleNausea in early pregnancy. The best-studied kitchen remedy for nausea. Trials support it for pregnancy and after surgery; the evidence for joint and period pain is thinner.
- HoneyAcute cough in children over 1 year. A spoonful of honey has decent trial support for children's coughs at night. It must never be given to a baby under 12 months because of infant botulism.
- KiwifruitActinidia deliciosaChronic constipation. Two green kiwifruit a day is one of the best-tested food approaches to constipation, and the gentlest on the gut. The sleep research is small and uncontrolled.
- Oily fishHeart health as part of the diet. Salmon, sardines, mackerel and their kin are the main food source of the omega-3s EPA and DHA. The case for eating them is stronger than the case for fish oil capsules.
- PeppermintMentha x piperitaAbdominal pain in people with IBS (oil capsules). Enteric-coated peppermint oil capsules have consistent trial support for abdominal pain in people with IBS. Peppermint tea is pleasant but untested, and peppermint can make heartburn worse.
- PrunesPrunus domestica (dried plums)Constipation. The old remedy holds up: in trials, a daily handful of prunes improved constipation about as well as a fiber supplement. Research on bone density is early.
- Tart cherryPrunus cerasus (Montmorency)Recovery after strenuous exercise. Tart cherries contain melatonin and plant pigments, and small trials show modest effects on sleep. The better evidence is for recovery after hard exercise.
- TurmericCurcuma longaKnee osteoarthritis pain. Curcumin capsules have eased knee osteoarthritis pain in trials, but cooking with turmeric delivers very little curcumin, and some high-absorption products have been linked to liver injury.
Limited Early or mixed
A few small trials, conflicting results, or evidence mostly from lab, animal or observational studies. Worth knowing about, not worth relying on.
- BeetrootBeta vulgarisLower blood pressure readings. Beets are rich in dietary nitrate, which the body turns into nitric oxide. Short trials show a small drop in blood pressure measured at the clinic; longer, more careful measurements have not confirmed it.
- ChamomileMatricaria chamomillaSleep quality. A traditional bedtime tea with small, inconsistent trials behind it. It may nudge sleep quality; it has not been shown to help insomnia.
- Chicken soupShort-term relief of a stuffy nose. The most famous food remedy of all. The studies behind it are small lab experiments, but a hot, salty, savory broth does bring short-term relief and fluids.
- CinnamonCinnamomum verum and C. cassiaBlood sugar in type 2 diabetes. Mixed trial results for blood sugar and no change in long-term HbA1c. Cassia cinnamon, the common supermarket kind, carries coumarin, which limits how much is sensible.
- EchinaceaEchinacea purpurea, E. angustifoliaLower chance of catching a cold. One of the most-tested herbs for colds. The trials point to, at best, a small drop in the chance of catching a cold and no clear effect on how long one lasts.
- ElderberrySambucus nigraFlu symptoms. A popular syrup with a short, conflicting trial record. Early small studies suggested faster recovery from flu; the most carefully run recent trial found none. Raw berries are toxic until cooked.
- FennelFoeniculum vulgareBloating and wind after meals. A traditional after-dinner seed for wind and bloating, recognized by European regulators on the strength of long use rather than trials. Colic studies in babies are small.
- Fermented foodsGut microbiome diversity. Sauerkraut, kimchi, miso, kefir and kombucha. One well-run trial suggests eating more of them changes the gut microbiome; claims beyond that are mostly untested in people.
- Green teaCamellia sinensisLDL cholesterol. As a drink, green tea is safe for most adults and may nudge cholesterol and blood pressure down a little. Extract pills are a different matter.
- Licorice rootGlycyrrhiza glabraSore throat after a breathing tube (gargle). A traditional throat and stomach remedy with thin evidence and a well-documented downside: regular licorice can raise blood pressure and drop potassium.
Not supported Tested and failed, or untested
Good trials found no benefit, or the claim has never been tested in people. Popular is not the same as proven.