European Primary Care Cardiovascular Society

Finnish men who eat more eggs have lower risk of incident type 2 diabetes

Literature - Virtanen J et al., Am J Clin Nutr 2015

Egg consumption and risk of incident type 2 diabetes in men: the Kuopio Ischaemic Heart Disease Risk Factor Study

Virtanen J, Mursu J, Tuomainen TP  et al  
Am J Clin Nutr 2015; DOI: 10.3945/ajcn.114.104109


In the search for modifiable risk factors for type 2 diabetes (T2D), dietary factors are a logical path to take, considering evidence from observational and experimental studies.
Egg consumption, as a major source of dietary cholesterol, has been implicated as a possible risk factor. It has been associated with impaired glucose metabolism [1] and increased inflammation [2] in animal models, and with elevated fasting glucose [3] and higher risk of T2D [4,5] in humans. Addition of eggs to the diet in randomised controlled trials, however, has reduced plasma insulin and insulin resistance [6], decreased inflammatory markers [7-9] and increased formation of larger and less-dense LDL and HDL particles [6,10].
The effect of egg consumption on the risk of T2D is unclear. This study therefore set out to investigate the association between egg consumption and risk of incident T2D in middle-aged and older men from eastern Finland. Egg consumption has previously been shown not to be associated with carotid atherosclerosis or risk of myocardial infarction in this study population [11]. Consumption of food was assessed at baseline with a guided food record of 4 consecutive days, one of which was a weekend day, including indication of portion sizes. The egg consumption variable reflected total egg consumption, including eggs in mixed preparations. Average follow-up duration was 19.3 years (SD: 6.6 years, range: 0.2-26.8 years, 45008 person-years).

Main results

  • After adjustment for age, examination year and energy intake, a lower risk of T2D was seen with increasing egg intake (P-trend across quartiles: < 0.001), with the third egg intake quartile (median: 35 g/day) already showing the lowest risk (relative risk reduction third vs. lowest quartile (median intake: 9 g/d): 37% (95%CI: 17-52%, absolute risks: 13.2% in the 3rd vs. 21.0% in 1st quartile). Higher intake did not provide further risk reduction.
  • Each additional egg per day (55 g) was associated with 30% lower risk (HR: 0.70, 95%CI: 0.55-0.90). Adjustment for cholesterol intake strengthened the association slightly.
  • Cholesterol intake was not associated with the risk of T2D, after correction for age, examination year and energy intake. After further correction for confounders, cholesterol intake showed a similar risk pattern across quartiles to egg consumption. Further adjustment for egg consumption weakened the association.
  • Higher egg intake was associated with modestly lower plasma glucose concentrations at baseline and at the 4-year examination, and with lower CRP at the 4-year examination.
  • Dietary cholesterol was associated with higher glucose and insulin concentrations at baseline, in particular after adjustment for egg intake. No significant relations with glucose or insulin were seen after 4 years.
  • Sensitivity analysis of the association between egg intake and T2D incidence after 10 years of follow-up also showed a lower risk of T2D with increasing quartiles of egg consumption.


In this prospective cohort of middle-aged and older Finnish men, higher egg intake was associated with lower risk of incident T2D. Looking into metabolic risk markers suggests an inverse relation with fasting plasma glucose and serum CRP, but not with serum insulin.
Adjustment for potential risk factors did not have a large impact on the observed associations, suggesting that in this study cohort egg consumption was not just a surrogate for some other unhealthy lifestyle factors that could explain the association with risk of T2D.
Eggs are a major contributor to cholesterol intake. Egg and cholesterol intake showed similar inverse associations with T2D risk, but the association with cholesterol intake mostly appeared to be accounted for by egg intake. Eggs are also a rich source of many nutrients that may affect health in a positive way. These findings suggest that recommendations to limit the consumption of eggs in a generally healthy population should not be based on a single food component like cholesterol.
Find this article online at The American Journal of Clinical Nutrition


1 Adamopoulos PN, Papamichael CM, Zampelas A, et al. Cholesterol and unsaturated fat diets influence lipid and glucose concentrations in rats. Comp Biochem Physiol B Biochem Mol Biol 1996; 113:659–63.
2 Lewis KE, Kirk EA, McDonald TO, et al. Increase in serum amyloid a evoked by dietary cholesterol is associated with increased atherosclerosis in mice. Circulation 2004; 110:540–5.
3 Feskens EJ, Kromhout D. Habitual dietary intake and glucose tolerance in euglycaemic men: the Zutphen Study. Int J Epidemiol 1990;19: 953–9.
4. Meyer KA, Kushi LH, Jacobs DR Jr., et al. Dietary fat and incidence of type 2 diabetes in older Iowa women. Diabetes Care 2001; 24:1528–35.
5. Salmerón J, Hu FB, Manson JE, et al. Dietary fat intake and risk of type 2 diabetes in women. Am J Clin Nutr 2001;73:1019–26.
6. Blesso CN, Andersen CJ, Barona J, et al. Whole egg consumption improves lipoprotein profiles and insulin sensitivity to a greater extent than yolk-free egg substitute in individuals with metabolic syndrome. Metabolism 2013;62:400–10.
7. Ratliff JC, Mutungi G, Puglisi MJ, et al. Eggs modulate the inflammatory response to carbohydrate restricted diets in overweight men. Nutr Metab (Lond) 2008;5:6.
8. Blesso CN, Andersen CJ, Barona J, et al. Effects of carbohydrate restriction and dietary cholesterol provided by eggs on clinical risk factors in metabolic syndrome. J Clin Lipidol 2013;7:463–71.
9. Andersen CJ, Lee JY, Blesso CN, et al. Egg intake during carbohydrate restriction alters peripheral blood mononuclear cell inflammation and cholesterol homeostasis in metabolic syndrome. Nutrients 2014;6:2650–67.
10. Mutungi G, Waters D, Ratliff J, et al. Eggs distinctly modulate plasma carotenoid and lipoprotein subclasses in adult men following a carbohydrate-restricted diet. J Nutr Biochem 2010;21:261–7.
11. Voutilainen S, Nurmi A, Mursu J, T et al. Regular consumption of eggs does not affect carotid plaque area or risk of acute myocardial infarction in Finnish men. Atherosclerosis 2013;227:186–8.

Share this page with your colleagues and friends: