ABC | Volume 110, Nº6, June 2018

Viewpoint Update of the Impact of Consumption of Whole Chicken Eggs on the Lipid Profile: to What Extent are They Impacting? Heitor Oliveira Santos Universidade Federal de Uberlândia (UFU), Uberlândia, MG - Brazil Mailing Address: Heitor Oliveira Santos • Av. Pará, 1720. Postal Code 38400-902, Uberlândia, MG – Brazil E-mail: heitoroliveirasantos@gmail.com Manuscript received July 10, 2017, revised manuscript September 02, 2017, accepted September 29, 2017 Keywords Cholesterol / chemistry; Eggs / utilization; Egg Proteins; Egg Proteins, Dietary; Antioxidants. DOI: 10.5935/abc.20180092 Introduction The older literature (mid 1980-90) shows that increased dietary cholesterol intake can raise total serum cholesterol and LDL levels. 1,2 Some more current positions question the recommendation of daily cholesterol intake, as well as the impact of the whole chicken egg, inquiring whether it is a harmful or beneficial classification food in this context. 3,4 In the midst of controversial issues, it is essential to analyze variables such as food consumption in general and how much dietary cholesterol intake is impacting on the parameters of the lipid profile, thus obtaining a more reliable information, mainly when the focus is the clinical conduct. One of the foods most known to contain cholesterol is the egg, and it is in the yolk where the cholesterol is concentrated. The chicken egg is the most consumed worldwide, being a food of affordable price, and, above all, of practical cooking and good nutritional profile. 3 Among the types of cooking, the fried chicken egg, stir-fried, cooked, pochê, roast, in the form of omelet and soufflés, besides being an ingredient of various preparations, stands out. The nutritional aspects of the chicken egg are extensive. It is a source rich in proteins of high biological value, unsaturated fats, liposoluble vitamins (mainly vitamin A and E), vitamin B12 and antioxidant components. 3 I carried out studies of great sample character, exhibiting interesting adjustments through the ingestion of chicken eggs. Data from observational methodology and human intervention support new research. 5,6 Hence, we sought to analyze the impact of the intake of whole chicken eggs on the lipid profile from older and recent studies. Pre-established studies: discussion of research in the mid‑2000s In 2000, McNamara 7 through a review encompassing a survey of 167 studies, whereof cholesterol intake in more than 4000 individuals was analyzed, shows that every 100 mg of dietary cholesterol intake the total plasma cholesterol increased only 2.2 mg/dL. A whole chicken egg unit (~ 50 g) contains a cholesterol content equivalent to the amount analyzed in the McNamara study, 7 presenting approximately 100-150 mg of cholesterol, 8 therefore, being one of the main foods that provided the increase of the cholesterol intake. 7,8 Regarding the LDL and HDL lipoproteins, the addition of 100 mg of cholesterol per day from the diet in the general McNamara 7 population increased the LDL levels by 1.9mg/dL and HDL levels by 0.4 mg/dL. Nevertheless, the mean change in the proportion of LDL: HDL per 100mg of dietary daily cholesterol in the patients was 2.60 to 2.61, that is, both values were literally negligible for the outcome of cardiovascular problems, such as plaque atheroma and stroke. 7 McNamara 7 also shows the relationship of dietary cholesterol response to heterogeneity, whose people are divided into hypersensitive and hypersensitive. According to the author, 15% to 25% of the population is sensitive to dietary cholesterol, in which there is a genetic increase in the production of apolipoprotein E4 and apolipoprotein B. However, the impact of daily dietary cholesterol intake per 100mg increased by only 1.4 mg/dL of total cholesterol levels in hypo-responsive individuals and 3.9 mg/dL in hyperresponsive individuals. 7 However, McNamara 7 does not emphasize whether the main food responsible for dietary cholesterol was chicken egg. A subject to analyze is the response of the lipid profile of patients with dyslipidemia to the eggs ingestion. In 1997, Knopp et al. 9 already had data for this issue. Knopp et al. 9 conducted a very well controlled study involving 130 patients with hypercholesterolemia and combined hyperlipidemia. For six weeks was used a diet based on traditional recommendations, and from that period randomized patients to receive two whole chicken eggs per week or at most one whole chicken egg per week, lasting 12 weeks. They analyzed the lipid profile before and after the intervention and observed that patients with hypercholesterolemia who consumed two eggs daily increased their HDL levels by an average of 48 to 52 ng/dL (p = 0.003), while they did not change other markers such as LDL, total cholesterol, VLDL and apolipoprotein B. On the other hand, patients with combined hyperlipidaemia who consumed two eggs per day increased mean total cholesterol from 238 to 250 ng/dL (p = 0.001), LDL from 150 to 162 ng/dL (p = 0.001), HDL from 42 to 45 ng/dL (p = 0.02), and apolipoprotein B (p = 0.05). A decrease in VLDL from 103 to 95 mg/dL (p = 0.007) was observed in this study, which was probably not expected. 9 Current studies: from large population samples to intervention with good control of intakes of whole chicken eggs A recently published study showed that consumption between two to four (n = 4493) and greater than four 585