Heart attacks and strokes are leading causes of death globally. Despite significant progress in identifying risk factors for these diseases over the past few decades, there are still uncertainties.
A recent study published in Nature Medicine suggests that individuals with higher levels of nicotinic acid, also known as vitamin B3, in their blood may be at a greater risk of experiencing heart attacks or strokes compared to those with lower levels.
Vitamin B3 is a popular supplement. Image Source: SERSOL/Alamy
Vitamins are often added to fortified foods that can be taken as supplements, but excessive amounts of vitamins can cause inflammation in the blood vessels.
"If you treat high cholesterol, high blood pressure, and diabetes, eliminate all existing risk factors, and still may suffer a heart attack, it means we missed something," said Stanley Hazen, the lead author of the paper and a researcher at the Cleveland Clinic in the United States.
To fill in these gaps, Hazen and colleagues collected blood samples from 2,331 adults in the United States and 832 European adults selected to undergo cardiovascular screening. The research team analyzed substances called metabolites in the samples, which are byproducts of processes like digestion. Subsequently, the researchers tracked whether participants experienced heart-related events such as heart attacks and strokes for over three years.
The results found that people with higher levels of a metabolite called 4PY in their blood were on average 60% more likely to experience such events than those with lower levels. 4PY is only produced when the body breaks down excessive amounts of vitamin B3.
Further experiments showed that 4PY causes inflammation in the blood vessels of rodents. "We know that inflammation is a major factor leading to heart disease," explained Hazen.
High levels of vitamin B3 in the body are not uncommon. This is partly due to certain foods, such as grains and flour, which are frequently fortified with vitamins in countries including the UK and the US.
Hazen noted that vitamin B3 supplements are becoming increasingly popular due to evidence suggesting they have anti-aging effects. Additionally, it wasn't until recently that doctors stopped prescribing high-dose vitamin B3 to people at risk of cardiovascular disease, as it was initially believed that vitamins could protect people from these diseases by lowering cholesterol.
"This study primarily focuses on people of European descent. It is currently unclear whether similar results would occur in individuals of different racial or ethnic backgrounds," said Jenny Jia from Northwestern University in the US.
Related paper information: https://doi.org/10.1038/s41591-023-02793-8
