A new analysis found that for each additional 300 milligrams a day of cholesterol in the diet — and the more eggs you ate — the greater the risk for cardiovascular disease.

By Nicholas Bakalar, March 15, 2019

Some nutrition experts say eggs are good for you, even though they are high in cholesterol. Others are sure they are bad. A large new study may help resolve at least some of the confusion.

The new analysis looked at data from six large prospective studies involving almost 30,000 participants, with an average follow-up of more than 17 years. It found that for each additional 300 milligrams a day of cholesterol in the diet, there was a 17 percent increased risk of cardiovascular disease and an 18 percent increased risk of premature death from any cause.

Eggs alone — a large egg has about 185 milligrams of cholesterol, all of it contained in the yolk — had the same more-is-worse effect. Each additional half-egg a day was associated with a 6 percent increased risk of cardiovascular disease and an 8 percent increased risk of early death.

The study findings are observational and cannot establish cause and effect. But no matter how heart-healthy the rest of a person’s diet, the more eggs consumed, the greater the risk for cardiovascular events, coronary heart disease, stroke, heart failure and premature death. The same was true for dietary cholesterol, independent of other dietary characteristics: The more cholesterol in your diet, the higher the risk for disease. The findings were published in JAMA. 

Comentario: Aunque estos resultados son coherentes con el hecho  conocido de que el colesterol de la dieta aumenta el nivel plasmático del colesterol ligado a la lipoproteina total y de baja densidad y puede acelerar el desarrollo de la ateroesclerosis y sus complicaciones, es sabido también que la respuesta individual a los cambios en el colesterol de la dieta varía ampliamente, sugiriendo determinantes genéticos y mecanismos fisiológicos de adaptación en el mantenimiento de los niveles de colesterol plasmático. Es conocido el clásico trabajo de Fred Kern Jr., publicado  en el NEJM hace casi treinta años (N Engl J Med 1991; 324:896-899), que objetivó que una menor absorción intestinal y una menor síntesis hepática de colesterol contribuían a mantener un nivel plasmático normal de colesterol (entre 150-200 mg/ml) en un paciente que había ingerido 25 huevos diarios durante un largo período de tiempo. Este mecanismo de adaptación ha sido demostrado en otros estudios pero en todo caso del reciente análisis de Nikolas Bakalar se deduce la conveniencia de controlar frecuentemente los niveles plasmáticos de colesterol para vigilar el efecto que sobre dicho nivel pueda tener una dieta rica en huevos.