Ingredients, one at a time

The most used herbal for prostate symptoms and the one with the clearest negative result. The 2023 Cochrane review of 27 placebo-controlled studies and 4,656 men concluded it provides little to no benefit. The reason it feels like it works is on this page.

The largest trial, 1,431 men over a year, found whole pumpkin seed beat placebo and a pumpkin seed extract did not. The cold-pressed oil in most softgels, including the one linked on this page, was not tested in that trial at all, so neither capsule form has the result the whole seed has.

A plant sterol with some of the cleanest trial results in the category: better flow and less urine left behind across four trials, and a 4.9-point improvement in symptom score against placebo in the two that measured it. It does not shrink the prostate, and the trials are thirty years old.

The best effect size in the category, from the weakest set of trials. Men were more than twice as likely to report improvement, nocturia fell 19 percent and peak flow rose 23 percent, across 18 trials averaging just 64 days with almost no allocation concealment.

The one prostate supplement whose trials point squarely at night-time urination. Men taking it were roughly twice as likely to report improved symptoms and twice as likely to report less nocturia than men on placebo. It does nothing for flow rate, residual volume or prostate size.

The best-studied supplement for fasting blood sugar, with meta-analyses showing meaningful reductions in fasting glucose and HbA1c in people with type 2 diabetes, smaller against placebo than the headline figures suggest. It also has the most side-effect discussion of any supplement in the category.

Two different claims with two very different levels of proof. That it switches off your ability to taste sweetness is established down to the receptor it binds. That it lowers blood sugar rests on small, low-quality studies: two non-randomised ones from 1990 and six randomised trials of low quality pooled in 2023.