Study finds link between too much niacin intake and heart disease

Feb. 19 (UPI) — A major new study shows excessive amounts of the common B vitamin niacin can lead to increased risk for cardiovascular disease, researchers announced Monday.

In a new study published in the journal Nature Medicine, scientists from the Cleveland Clinic say they have identified a strong link between 4PY, a breakdown product from excess niacin, and heart disease.

The results are important because they uncover a previously unknown driver of heart disease, according to Dr. Stanley Hazen, director of Cleveland Clinic’s Center for Microbiome and Human Health and the study’s lead author.

“What’s exciting about these results is that this pathway appears to be a previously unrecognized yet significant contributor to the development of cardiovascular disease,” Hazen said in a statement.

“What’s more, we can measure it, meaning there is potential for diagnostic testing,” he added. “These insights set the stage for developing new approaches to counteract the effects of this pathway.”

The study involved a “discovery cohort” of 1,162 stable cardiac patients and a pair of validation cohorts totaling 2,331 patients, as well as a further investigation of the cardiac effect of 4PY in mice.

Niacin, also known as Vitamin B-3, is very common in Western diets — in fact, since the 1940s more than 50 nations have mandated niacin fortification in staple foods such as flour, cereals and oats to prevent disease related to nutritional deficiency.

It has been prescribed for many years as a way to counter high cholesterol and over-the-counter dietary supplements containing the vitamin have emerged as popular products to combat the aging process.

However, the new study shows that too much niacin can lead to inflammation of blood vessels, which is strongly linked to heart disease. One in four subjects in the researchers’ patient cohorts appeared to be getting too much niacin, causing a “spillover” effect in which the body’s production of the harmful 4PY metabolite is triggered, the researchers found.

The results suggest that while proper levels of niacin remain essential for human health, “a discussion over whether a continued mandate of flour and cereal fortification with niacin in the U.S. could be warranted,” Hazen said.

He also suggested that supplements containing niacin should probably not be consumed without prior consultation with a doctor and instead be substituted with a diet rich in fruit and vegetables.