Eggcellent eggs part II: can people with diabetes safely eat two eggs per day?

The U.S. Dietary Guidelines do not lay out recommendations for egg consumption and acknowledge that dietary cholesterol (about 200 milligrams in one large egg) is not a nutrient that people should be worrying about. Similarly, the American Diabetes Association lists whole eggs as an acceptable source of dietary protein without any apparent recommendations for intake levels. Yet, both Healthline and the Diabetes Council state that egg consumption should be limited to about three eggs per week.

Can eating more than three eggs per week when you have type II diabetes really be a health risk, though?

A recent observational study^[1] following over 9,000 Korean adults reported that a significant association existed between egg consumption and an increased risk of heart disease in people with type II diabetes — a 2.8-fold greater risk among people who ate about four eggs per week compared to those who ate close to none. On the other hand, the PREDIMED study^[2] reported no significant association between heart disease and egg consumption in over 7,000 participants, regardless of whether a participant had diabetes or not.

One meta-analysis^[3] of five observational studies suggested that eating more than one egg per week was associated with increased heart disease death rates among people with diabetes, compared to eating less than one egg per week. However, a subsequent systematic review^[4] suggested that these studies did not adequately adjust for confounding variables, such as other dietary components.

Long, long ago, in an NERD issue you may have forgotten (NERD #7), we analyzed preliminary findings^[5] from the Diabetes and Egg (DIABEGG) study, which looked at how eating two eggs per day, six days per week, affected blood lipids, glycemic control, inflammation, and body composition during a three-month invention in people with type II diabetes and prediabetes. Eating eggs had no effect on any outcome, a finding also shared by other randomized controlled trials^[6].

However, a primary limitation with all interventions to date is that they are relatively short, lasting no more than several months. At least, until now. The study under review is the final publication of the DIABEGG study, looking at changes in heart disease risk factors over an entire year, making it the longest trial to date investigating the effects of egg consumption in people with type II diabetes.

Guidelines for egg consumption vary for people with type II diabetes, with some authorities having no guidelines and others saying to limit consumption to about three per week. However, controlled trials investigating the health effects of egg consumption in people with diabetes are relatively short, lasting no more than several months. The study under review is the longest egg intervention study to date, clocking in at one year.