Stethoscope with heart


WASHINGTON — People who follow a low-carb diet are significantly more likely to develop atrial fibrillation (AFib), according to new research.

Researchers with Sun Yat-Sen University in Guangzhou, China say that avoiding healthy carbohydrates such as grains, fruits, and starchy vegetables raises one’s risk of AFib, an irregular heartbeat that boosts the risk of stroke, heart failure, blood clots, and other cardiovascular ailments.

The study used data from more than 14,000 people who took part in a study on atherosclerosis (blocked arteries) risk led by the National Institutes of Health from 1985 through 2016. The authors say it’s the largest to link carbohydrate intake and AFib. After participants logged what they ate every day, researchers estimated each individual’s daily carbohydrate intake and the proportion of calories from carbs — which wound up being about half of a person’s total calories consumed, on average. That figure falls in line with the federal guideline of carbs counting for 45 to 65 percent of total daily calorie consumption.

Researchers found that nearly 1,900 participants were diagnosed with AFib in follow-up surveys an average of 22 years later.

Participants were then split into three groups based on daily carb intake — either low, moderate, or high, with low being considered less than 44.8 percent of daily calories, and high being over 52.4 percent. In comparing cases of AFib to carbohydrate intake, they found that those who consumed low-carb diets were most likely to develop the condition, with an 18% greater risk compared to those in the moderate group, and a 16% greater risk than those who consumed high-carb diets.

“The long-term effect of carbohydrate restriction is still controversial, especially with regard to its influence on cardiovascular disease,” says lead author Dr. Xiaodong Zhuang, a cardiologist at the hospital affiliated with Sun Yat-Sen University, in a media release by the American College of Cardiology. “Considering the potential influence on arrhythmia, our study suggests this popular weight control method should be recommended cautiously.”

Atrial fibrillation is the most common heart rhythm disorder, affecting about 2.7 million Americans, according to the American Heart Association. Those diagnosed with the disease are five times more likely to suffer a stroke, and twice as likely to die from a heart condition.

Zhuang suggests that the risk for low-carb dieters is greater because low-carb diets tend to include fewer vegetables, fruits and grains, which naturally help reduce inflammation. It’s also possible that eating more protein and fat instead of carbohydrates could raise the risk for oxidative stress, which is also linked to atrial fibrillation. The findings showed that no matter how dieters replaced carbs or which low-carb diet they followed, the risk was still the same.

Low carbohydrate diets were associated with increased risk of incident AFib regardless of the type of protein or fat used to replace the carbohydrate,” says Zhuang, who adds that the findings were observational, as opposed to cause-and-effect.

The study was presented at the American College of Cardiology’s 68th Annual Scientific Session.

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