The risk of heart disease and death increases with the number of eggs an individual consumes, according to a UMass Lowell nutrition expert who has studied the issue.

Research that tracked the diets, health, and lifestyle habits of nearly 30,000 adults across the country for as long as 31 years has found that cholesterol in eggs, when consumed in large quantities, is associated with ill health effects, according to Katherine Tucker, a biomedical and nutritional sciences professor in UMass Lowell's Zuckerberg College of Health Sciences, who co-authored the analysis. The study was published in the Journal of the American Medical Association.

The study results come as egg consumption in the country continues to rise. In 2017, people ate an average of 279 eggs per year, compared with 254 eggs in 2012, according to the US Department of Agriculture.

Current US Dietary Guidelines for Americans do not offer advice on the number of eggs individuals should eat each day. The guidelines, which are updated every 5 years, do not include this because nutrition experts had begun to believe saturated fats were the driving factor behind high cholesterol levels, rather than eggs, according to Tucker. However, prior to 2015, the guidelines did recommend individuals consume no more than 300 milligrams of cholesterol a day, she said.

One large egg contains nearly 200 milligrams of cholesterol, roughly the same amount as an 8-ounce steak, according to the USDA. Other foods that contain high levels of cholesterol include processed meats, cheese, and high-fat dairy products.

While the new research does not offer specific recommendations on egg or cholesterol consumption, it found that each additional 300 milligrams of cholesterol consumed beyond a baseline of 300 milligrams per day was associated with a 17% higher risk of cardiovascular disease and an 18% higher risk of death.

Eating several eggs a week "is reasonable," said Tucker, who noted they include nutrients beneficial to eye and bone health. "But I recommend people avoid eating three-egg omelets every day. Nutrition is all about moderation and balance."

Research results also determined that study participants' exercise regimen and overall diet quality, including the amount and type of fat they consumed, did not change the link between cholesterol in one's diet and risk of cardiovascular disease and death.

"This is a strong study because the modeling adjusted for factors such as the quality of the diet," Tucker said. "Even for people on healthy diets, the harmful effect of higher intake of eggs and cholesterol was consistent."