They drew their data from a dozen potential cohorts of earlier studies on the association between eating eggs and the risk of the most common form of diabetes. Nearly 220,000 individuals from the U.S., Japan, Finland, Spain, and France participated in the studies.
Close to 9,000 of these people had Type 2 diabetes. Both healthy and diabetic participants provided self-reported data on the number of eggs they ate over follow-up periods that lasted five to 20 years.
The Harvard Clinical and Translational Science Center (Harvard CATALYST) researchers organized the results before comparing the statistics of the high-consumption and low-consumption groups. Their findings showed that eating less than four eggs each week did not seem to be connected to much higher risks of Type 2 diabetes.
Also, the data from the non-U.S. studies did not find any risk of diabetes for people who ate more than three eggs each week. Only the U.S. studies showed a relative risk.
Three studies find no evidence linking egg consumption to Type 2 diabetes
The findings of the Harvard CATALYST study matched those in an earlier meta-analysis. Conducted by Indiana University (IU) researchers, the 2013 study compared the risk of diabetes in people who ate one egg every day with the risk of people who do not eat eggs.
The IU researchers did not find any evidence linking eggs with cardiovascular disease, ischemic heart disease, mortality, or stroke. They did notice that patients diagnosed with diabetes were more prone to developing cardiovascular morbidity if they ate an excessive amount of eggs.
In turn, the IU study is backed by another 2013 experiment, this one supported by Huazhong University of Science and Technology (HUST). The two studies indicated that people at risk of Type 2 diabetes or patients with the disease should limit their consumption of whole eggs to avoid cardiovascular morbidity.
Processed foods eaten alongside eggs may be responsible for risks of diabetes
Meanwhile, going back to the Harvard study, the authors noticed the difference in the chances of Type 2 diabetes between U.S. and non-U.S. cohorts. They wondered if the difference came from other diet-related factors and general dietary patterns.
U.S. diets accompany eggs with bacon, sausage, and other processed food. The companion foods might contribute to the risk of diabetes in American participants.
Furthermore, the Harvard researchers noted that earlier studies did not find any connection between dietary cholesterol and Type 2 diabetes. CSIRO research from 2011 showed that high-protein diets with daily servings of two eggs induced weight loss and improvements in both diabetic patients and people suffering from poor glucose tolerance.
Eggs will not make a person more vulnerable to diabetes
The studies show that eggs do not deserve the blame for increasing the risk of Type 2 diabetes. Patients who already have Type 2 diabetes might need to reduce their consumption of whole eggs, but healthy individuals have nothing to fear, especially if they are already following a healthy diet and get lots of physical exercises.
Instead of worrying about eggs, people need to worry more about abdominal obesity. There is plenty of scientific evidence that establishes a strong connection between Type 2 diabetes and obesity.
In summary, eggs are nutritious foods that are rich in proteins and other beneficial compounds. Eating one or two a day as part of a healthy diet and active lifestyle will bring far more health benefits than adverse effects.