Are Eggs as Bad as Cigarettes?
A reader recently reached out to us after reading an article that said eating eggs is just as bad for your arteries as smoking, wondering if this is true. Considering that the average American consumer eats 248 eggs each year, we thought this was a very good question. To explore the topic, we reached out to Dr. Maria Luz Fernandez, a professor in the Department of Nutritonal Sciences at the University of Connecticut.
Is it true? Is eating eggs just as bad for your arteries as smoking?
Dr. Fernandez:
“There are some flaws in this study that lead me to conclude it is not true. When looking at this study, we need to consider the methodology. First of all, the subjects under study were already sick and came to the clinic with high blood pressure, hyperlipidemias and excess body weight. This is also a cross-sectional study, thus it is not possible to reach a causal conclusion.
“Secondly, the authors use a strange way to express consumption of eggs – egg years. It is not surprising that the individuals with more egg years (older) had higher plaque area. So a big problem with the study is that they did not control their data with age, which as we all know is highly associated with heart disease and high lipid levels.
“Next, the authors did not use a standardized dietary questionnaire. They only asked for egg intake (a biased question) and smoking. They did not control for other dietary items. There are many dietary variables that lead to heart disease (saturated fat, high sugar intake, less consumption of fruits and vegetables). It is an unreliable study if only eggs are part of the analysis.
“Finally, this study did not include data of 57 percent of patients coming to the clinic, which may also introduce a bias. It is also strange that the study found higher total cholesterol is associated with less plaque. Looking at all of the information in this study, the conclusions are really overstated based on the data.”
Is it OK to eat eggs?
Dr. Fernandez:
“Eggs possess many nutritional attributes including high quality protein, essential vitamins and minerals. At the same time, they do not increase the risk for cardiovascular disease [1]. The lack of correlation between egg intake and coronary heart disease risk is not surprising given several facts:
- Egg intake consistently results in elevations of HDL cholesterol even under specific circumstances such as weight loss, where LDL cholesterol is not raised [2],[3]. Thus the LDL/HDL, a key marker of coronary heart disease risk, is maintained or even reduced.
- Eggs contain lutein, a carotenoid that is selectively removed by the eye and protects against macular degeneration and the development of cataracts [4]. It has also been shown that lutein from eggs is much more bioavailable than from other dietary sources [5]. Further, it has been shown that lutein also protects against oxidative stress [6], inflammation [7] and atherosclerosis [8].
- Eggs are a good source of choline, which plays a major role in normal fetal development [9],[10] and may also protect against Alzheimer’s disease [11].
- Eggs have been shown to suppress appetite [12] and decrease caloric intake during the next 24 hours [13].
- Eggs are an affordable source of high quality protein as recently stated by a comprehensive report on nutrient-dense foods [14].
- Lastly, less consumption of eggs has been correlated with the development of certain types of malnutrition [15] in underdeveloped countries [16]. The European Union and countries such as India, South Korea, Canada, New Zealand and others [17] have no dietary guidelines for dietary cholesterol. However, these countries do have clear and well-defined guidelines regarding total fat, saturated fat and trans fatty acids. Therefore, there is a worldwide consensus regarding saturated fat, while clearly that is not the case for dietary cholesterol.
“Eggs should not be eliminated from the diet because they not only provide a substantial amount of nutrients but they also have health benefits that go beyond nutrition.”
REFERENCES
[1]. Fernandez ML. Rethinking dietary cholesterol. Curr. Opinions Med Nutr Metabolic Care. 2012; 15:17-21.
[2] Mutungi G, Ratliff J, Puglisi M, Torres-Gonzalez M, Vaishnav U, Leite JO, Quann E, Volek JS, Fernandez ML. Dietary cholesterol from eggs increases HDL cholesterol in overweight men consuming a carbohydrate restricted diet. J. Nutr. 2008;138:272-276.
[3] Harman NL, Leeds AR, Griffin BA. Increased dietary cholesterol does not increase plasma low density lipoprotein when accompanied by an energy-restricted diet and weight loss. Eur J Nutr. 2008;47:287-293.
[4] Vishwanathan R, Goodrow-Kotyla EF, Wooten BR, Wilson TA, Nicolosi RJ. Consumption of 2 and 4 egg yolks/d for 5 wk increases macular pigment concentrations in older adults with low macular pigment taking cholesterol-lowering statins Am J Clin Nutr. 2009;90:1272-9.
[5] Handelman GJ, Nightingale ZD, Lichtenstein AH et al. Lutein and zeaxanthin concentrations in plasma after dietary supplementation with egg yolk. Am J Clin Nutr 1999;70:247-251.
[6] Ribaya-Mercado JD, Blumberg JB. Lutein and zeaxanthin and their potential roles in disease prevention. J. Am Coll. Nutr. 2004:23:567S-587S.
[7]. Jin XH, Ohgami K, Shiratori K, Suzuki Y, Hirano T, Koyama Y, Yoshida K, Ilieva I, Iseki K, Ohno S. Inhibitory effects of lutein on endotoxin-induced uveitis in Lewis rats. Invest Ophthalmol Vis Sci. 2006 Jun;47:2562-8.
[8]. Dwyer JH, Paul-Labrador MJ, Fan J, Shircore AM, Merz CN, Dwyer KM. Progression of carotid intima-media thickness and plasma antioxidants: the Los Angeles Atherosclerosis Study. Arterioscler Thromb Vasc Biol. 2004;24:313-319.
[9] Shaw GM, Finnell RH, Blom HJ, Carmichael SL, Vollset SE, Yang W, Ueland PM. Choline and risk of neural tube defects in a folate-fortified population. Epidemiology. 2009;20:714-749.
[10] Mehedint MG, Craciunescu CN, Zeisel SH. Maternal dietary choline deficiency alters angiogenesis in fetal mouse hippocampus. Proc Natl Acad Sci U S A. 2010; 20;107(29):12834-12839.
[11]. Alcaro S, Arcone R, Costa G, De Vita D, Iannone M, Ortuso F, Procopio A, Pasceri R, Rotiroti D, Scipione L. Simple choline esters as potential anti-Alzheimer agents. Curr Pharm Des. 2010;16:692-697.
[12] Vander Wal JS, Marth JM, Khosla P, Jen KL, Dhurandhar NV: Short-term effect of eggs on satiety in overweight and obese subjects. J Am Coll Nutr 2005; 24:510-515.
[13]. Ratliff JC, Leite JO, DeOgburn R, Puglisi M, VanHeest J, Fernandez ML. Consuming eggs for breakfast influences plasma glucose and ghrelin, while reducing caloric intake during the next 24 hours in adult men. Nutrition Res. 2010; 30:96-103.
[14] Drewnowski A. The Nutrient Rich Foods Index helps to identify healthy, affordable foods. Am J Clin Nutr. 2010;91:1095S-1101S.
[15]. Sullivan J, Ndekha M, Maker D, Hotz C, Manary MJ. The quality of the diet in Malawian children with kwashiorkor and marasmus. Matern Child Nutr. 2006;2:114-122.
[16]. Jinadu MK, Ojofeitimi EO, Osifor EO. Feeding patterns of children with protein-energy malnutrition in Nigeria. Trop Doct. 1986;16:82-5.
[17]. Fernandez ML, Calle MC. Revisiting dietary cholesterol recommendations: does the evidence support a 300 mg/d limit? Current Atherosclerosis Reports 2010; 12:377-383.
Image: “Cigarettes – I hate cigarettes, but it’s so good.” by jphilipg is licensed under CC BY 2.0.