In 2009 a study of the nutrient composition of eggs produced
by controlled flocks of chickens, comparing cage vs. free range
production (Anderson, 2011) was conducted. In that study the
cholesterol content of whole large eggs was lower than reported
in the United States Department of Agriculture (USDA) Nutrient
Database for Standard Reference (SR) Release 22 (USDA, 2009).
The SR22 data on eggs were based on a 2000–2001 nationwide
sampling and analyses conducted by the USDA Nutrient Data
Laboratory (NDL) as part of the National Food and Nutrient
Analysis Program (NFNAP) (Haytowitz et al., 2007), in collaboration
with the Egg Nutrition Center (ENC)