After a 15-minute walk among trees, 585 young men scored 5.2 points lower for tension than after a city walk, and reviews find people report feeling better again and again. Blood pressure and cortisol move only a little, and nobody can be blinded to a forest.
A 2026 review found nine studies of the carnivore diet, two of them meal plans worked out on paper. In both of its surveys that measured LDL before and during the diet, LDL went up: by a typical 36 mg/dL in 14 volunteers' lab reports.
Sixty-three studies tie feeling hooked on your phone to worse sleep. The studies that tested direction found the pull runs both ways, and in small trials, a phone-free bedtime improved people's own ratings of their sleep.
In pooled trials melatonin shortens the time to fall asleep by a few minutes: about seven in a 2013 review, about two in adults alone in 2022. Europe licenses a 2 mg slow-release tablet for people 55 and over; the FDA has approved no dose. In a 2023 test, 22 of 25 US gummies were more than 10% from their label.
The signs that best pick out Cushing syndrome are physical: purple stretch marks more than about 0.4 in (1 cm) wide, bruising from nothing, weakness getting out of a chair. Tiredness is a feature too, and on its own it singles nobody out.
Vitamin D prevents and treats rickets and osteomalacia; that much is settled. The big trials mostly enrolled people who already had enough, and where they looked at the people who started low they mostly found no clear benefit. The official daily figures are 600 IU in the US (800 after 70) and 400 in Britain, with a ceiling of 4,000.
Methylene blue is a drug with one FDA-approved use: by vein, in hospital, for a poisoning. It is sold as drops for energy and focus. We found no trial of the drops. The trial sellers cite gave 26 healthy adults a single 280 mg capsule and could not tell its memory result from placebo. The boxed warning about antidepressants rests on hospital injections; by mouth, the FDA called the risk "not known" in 2011, and in 2025 Australia's regulator told consumers not to take it unless a health professional advises it.
The NIH's record on sea moss says no medicinal value has been proven. A placebo-controlled trial, written at a company that sells a sea moss ingredient, found no significant difference from placebo. The iodine in dried sea moss varies more than a hundredfold from bag to bag, and one brand recalled 5.4 million jars of gel in 2026.
NR and NMN capsules reliably raise NAD+ in blood. In pooled trials they did not significantly change weight, blood sugar, cholesterol or muscle, and none of the 33 human reports in the main review ran longer than 26 weeks. We found no published randomised trial of an NAD+ drip for ageing or wellness.
Cochrane's 2024 review: zinc may shorten a cold by about two days, at low certainty, and probably brings more side effects, mostly a bad taste and an upset stomach. On catching fewer colds its trials, mostly in children, found little or no effect. Zinc in the nose is a separate story, with an FDA warning from 2009.