Campesterol is a phytosterol, a plant-derived compound structurally similar to cholesterol. It is commonly found in many vegetables, nuts, and seeds. Scientific interest in campesterol, along with other phytosterols such as beta-sitosterol, has focused on their ability to support prostate health, particularly in the context of benign prostatic hyperplasia (BPH). Some clinical studies and systematic reviews have investigated the effects of phytosterols on urinary symptoms associated with BPH. For example, a meta-analysis published in the journal Lancet (1995) and subsequent reviews have found that beta-sitosterol, which often occurs alongside campesterol in plant extracts, can improve urinary flow and reduce symptoms of BPH. However, the majority of these studies do not specifically isolate campesterol but rather look at mixed phytosterol preparations.

The scientific rationale is based on the ability of phytosterols to modulate inflammation, inhibit 5-alpha reductase (an enzyme involved in prostate enlargement), and improve urinary parameters. While direct evidence for campesterol alone is limited compared to beta-sitosterol, its chemical similarity and co-occurrence in phytosterol mixtures support its potential role. Thus, the evidence for campesterol in supporting prostate health is moderate (rated 3/5), primarily due to extrapolation from studies on mixed phytosterols and beta-sitosterol, rather than robust, campesterol-specific clinical trials.