For decades, the United States food industry has added Niacin, also known as Vitamin B3, to flour, corn, and bread products to prevent Pellagra. A lack of this nutrient causes this disease.
Today, Pellagra is almost unknown across the country except for certain populations who are in extreme food poverty.
A new study published in Nature MedicineTrustedSource on February 19 suggests that excessive niacin consumption may increase the risk of heart disease.
Researchers focused on a metabolic product of excess Niacin known as 4PY.
Researchers didn’t set out to investigate the role of Niacin in cardiovascular diseases. They were instead trying to determine why some people still experience cardiovascular events when they are treated for other factors, such as high blood cholesterol and diabetes.
In their initial research, 4PY, whose full name is N1-methyl-4-pyridone-3-carboxamide, showed up as a possible marker in the blood for cardiovascular risk. The researchers then traced the compound to excess Niacin.
The study found that those who were in the highest 4PY quarter had a nearly two-fold higher risk of serious adverse cardiovascular events, such as heart attacks or strokes, than those in the lower quarter.
The study’s author, Dr. Stanley Hazen, is the chair of cardiovascular and metabolism sciences at Cleveland Clinic Lerner Research Institute, Ohio. He spoke to Healthline.
Researchers claim that 4PY increases the risk of cardiovascular disease through vascular inflammation, also known as inflammation of blood vessels.
Mixed Effects of Niacin on Heart
Niacin was used to prevent cardiovascular disease before the advent of statins that lower cholesterol.
Despite this, some research shows that Niacin does not reduce cardiovascular disease risk or offer no additional benefit if used with statins. One study found that niacin use may even increase the risk of premature death.
The new study also suggests that excessive Niacin can counteract the benefits of lower amounts of Niacin. For example, supports the nervous system source.
“While niacin used to be prescribed as a medication that lowers cholesterol, it has been outlawed because multiple studies have not found as much benefit for cardiovascular health as was initially believed,” said Dr. Cheng-Han Chen, an interventional cardiologist at MemorialCare Saddleback Medical Center, Laguna Hills, Calif., and the medical director of its Structural Heart Program.
Chen did not participate in the study.
He told Healthline that “this [new] study is going to put another nail into the coffin of the use niacin for heart disease.”
Chen warns, however, that more research will be needed to determine the link between excess niacin intake and cardiovascular disease. This is especially true for people who take niacin supplements.
How Much Niacin Is Too Much?
Adults need between 14 and 18 milligrams of Niacin each day to avoid a deficiency. It can be found in foods such as 6 ounces of tuna, 4 ounces of peanuts, and other fortified foods.
Researchers write that therapeutic levels of Niacin, such as those used in clinical studies for lowering cholesterol, are around 1,500-2,500 milligrams a day.
Hazen said that people who take Niacin prescription or over the counter were excluded from the analysis. The diet is the primary source of Niacin in the participants.
Researchers didn’t have any data on the amount of Niacin that participants consumed. Hazen noted that excessive niacin intake or other related compounds, such as nicotinamide, nicotinic acids, and nicotinamide-riboside, had been shown to increase 4PY levels, as well as 2PY.
In this study, 2PY, also known as N1-methyl-2-pyridone-5-carboxamide, was not linked to inflammation or a higher risk of cardiovascular disease events.
According to the National Health and Nutrition Examination Surveys 2017-2020, Americans tend to consume more Niacin than they need to avoid a deficiency. On average, Americans consume 37 milligrams of Niacin per day. The authors note that the survey also shows that less than 4% of adults consume less than 15 mg of Niacin per day.
Hazen believes that the findings require a rethinking of previous beliefs.
In a press release, he stated that the main takeaway was not to cut our intake of Niacin completely. That’s just not realistic. These findings warrant a discussion on whether the U.S. should continue to mandate flour and cereals fortified with Niacin.
Chen warns people against taking Niacin regularly, especially if their cardiovascular risk is higher. They should consult their doctor before taking Niacin.
He said that it was more difficult to avoid foods fortified with Niacin due to their widespread presence in the food supply chain. The public’s policy may require a closer look at the niacin-fortified foods.
Takeaway
Researchers discovered that those with high levels of a breakdown of excess Niacin were at a greater risk for major cardiovascular events, such as stroke and heart attack.
Researchers say that this breakdown product, known as 4PY, increases cardiovascular risk through inflammation of the blood vessels.
It is necessary to conduct more research in order to understand better the relationship between the different levels of excess Niacin and cardiovascular disease. Researchers are calling for a review of food fortification with Niacin.