Relationship between dietary niacin intake and erectile dysfunction: a population-based study

A large U.S. study found men with higher dietary niacin (vitamin B3) intake had a lower risk of erectile dysfunction (ED). Men in the highest third of niacin intake were 56% less likely to have ED compared to those in the lowest third. This link held true even after accounting for other factors like age, weight, and health conditions.

Overview

This 2024 epidemiological study (published in Translational Andrology and Urology) examined the relationship between dietary niacin (vitamin B3) intake and erectile dysfunction (ED) using data from the National Health and Nutrition Examination Survey (NHANES) — a large, nationally representative U.S. population sample. The dataset included thousands of adult men, with dietary intake assessed via 24-hour dietary recall and ED status determined by a validated questionnaire.

This is an observational study, so it does not establish that niacin prevents or treats ED — but the magnitude and consistency of the association make it a significant addition to the niacin research literature.

Key Findings

Men in the highest third of niacin intake were 56% less likely to have ED compared to men in the lowest third, after adjusting for age, body mass index, physical activity, smoking, alcohol use, diabetes, hypertension, and cardiovascular disease. This is a large effect for a dietary factor in an adjusted model.

The relationship was dose-dependent. Across tertiles of niacin intake, ED risk decreased progressively. Men in the middle tertile also had lower ED rates than the lowest group, consistent with a gradient rather than a threshold effect.

The association held across subgroups. Subgroup analyses showed the niacin–ED relationship was present in men with and without cardiovascular disease, with and without diabetes, and across age groups — suggesting the mechanism is not mediated solely through cardiovascular risk factor modification.

Proposed Mechanisms

The researchers propose several pathways through which niacin may reduce ED risk:

Endothelial function. Erection depends on nitric oxide (NO)-mediated vasodilation in penile vasculature. Niacin has been shown to raise HDL cholesterol and reduce LDL and triglycerides — lipid profiles associated with better endothelial health. A healthier vascular endothelium generates NO more effectively, supporting the erectile response.

Anti-inflammatory effects via GPR109A. Niacin activates GPR109A receptors in immune cells and vascular tissue, reducing production of pro-inflammatory cytokines. Chronic low-grade inflammation is a recognized contributor to endothelial dysfunction and ED.

NAD+ metabolism. As a precursor to NAD+, niacin supports mitochondrial function and cellular energy production in smooth muscle cells. The smooth muscle of penile corpora cavernosa must relax for erection to occur, and this process is energy-dependent.

Testosterone and gonadotropin axis. Some evidence (from animal and small human studies) suggests niacin’s effects on GH secretion and lipid metabolism may indirectly support testosterone production, though this is less established than the vascular mechanisms.

Clinical Context

A separate randomized controlled trial (Ng et al., 2011) found that niacin supplementation (1500 mg/day for 12 weeks) significantly improved erectile function in men with both ED and dyslipidemia, specifically for orgasmic function and intercourse satisfaction scores. The NHANES population data presented here, while observational, is consistent with that intervention finding.

Current dietary niacin intake in the U.S. population varies considerably — men in the lowest intake tertile may be consuming below optimal amounts from dietary sources alone (meat, fish, fortified grains). The study does not distinguish between niacin forms (nicotinic acid vs. niacinamide in food sources) or account for supplement use separately.

What This Means

This study adds to a growing body of evidence connecting niacin status to vascular and sexual health. The mechanisms are coherent: niacin improves lipid profiles, reduces vascular inflammation, supports endothelial function, and contributes to NAD+ synthesis — all of which feed into erectile physiology.

For researchers investigating niacin’s role in men’s health, this NHANES analysis provides the largest population-level evidence to date for the niacin–ED association. The 56% reduction in ED odds at higher dietary niacin intake, in a well-adjusted model, is a finding that warrants further investigation in prospective and interventional designs.