The analysis included more than 99,000 post-menopausal women from the Women’s Health Initiative Randomized Controlled Trials and Observational Study. Women were divided into four groups based on how much protein they ate (less than 58 grams [g] per day, 58–66 g/day, 66–74 g/day, and more than 74 g/day) and then monitored for an average of 10 years for new cases of afib. Researchers found that almost one-quarter (21.3 percent) of participants developed afib during the follow-up period. Women who ate 10–15 grams more protein per day than the current recommended amount had a significantly lower rate of afib. “Women with the lowest protein intake — which was roughly equivalent to the current recommended daily amount of protein in the United States — had the highest incidence of afib, and eating a little more was protective, even after taking into account other factors that can predispose someone to develop afib,” says Daniel Gerber, MD, a cardiovascular medicine fellow at Stanford University and the study’s lead author in a statement. About 2.7 million Americans are living with afib, according to the Centers for Disease Control and Prevention (CDC). Some people who have afib may not have any symptoms, while others may experience heart palpitations, light-headedness, extreme fatigue, or shortness of breath. Afib can lead to blood clots, heart failure, stroke and other heart complications. Because the risk for afib increases as you get older, and women tend to live longer than men, more women than men have the condition. “In general, women often don’t eat as much protein compared with men because they worry about calories when looking to lose weight,” says Martha Gulati, MD, a physician and the executive director of the Banner–University Medicine Heart Institute in Phoenix, Arizona. But as women get older, they tend to lose muscle mass, so protein may be especially important for this age group.
What This Means for Your Diet
In addition, higher-protein diets have been shown to aid in fat loss while maintaining lean muscle mass. A study published in February 2017 in the Journal of the Academy of Nutrition and Dietetics found a positive relationship between eating protein and the amount of lean muscle mass in post-menopausal women. “If a higher-protein diet is able to help people lose weight, this could reduce the risk of hypertension, high cholesterol, diabetes, and coronary artery disease, all of which would be cardiovascular benefits,” Gerber says. So, does that mean older women should eat more protein? “The study certainly shows that women who ate more protein had less afib, independent of physical activity,” says Dr. Gulati, who added that since the study wasn’t diet specific, more research is needed. “So, it shouldn’t be interpreted that a high protein diet like the keto diet was the intervention.” The study also didn’t specify the type of protein eaten, or the exact mechanism of protein and how it’s protective against afib, she notes. To lower your risk of afib, Gulati recommends that women keep a healthy weight and eat the recommended amount of protein — 0.8 grams of protein per kilogram of body weight, which is about 51 g per day for a 140-pound person.
