Eating eggs scientifically can improve your health

Author: Zhang Yu, researcher at Chinese Center for Disease Control and Prevention, master's supervisor

Reviewer: Fu Rui, Chief Physician, Beijing Century Altar Hospital, Capital Medical University

Eggs, with their rich nutritional value and rich taste, have been an indispensable part of the dining table since ancient times. Bai Juyi also praised them in his "Early Travel to Yuan Yuanwai": "Get up early in the morning, smoke rises, boil eggs, delicious and expensive." Nowadays, the "Dietary Guidelines for Chinese Residents" has included them as one of the must-eat foods every day.

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Eggs, also known as chicken eggs, have a hard shell on the outside and an air chamber, egg white and yolk inside. As a special egg, it has rich nutritional value. Each egg contains about 7 grams of protein and has a very high digestibility. In addition, it also contains a certain amount of vitamins A, B2, B12, D and E, as well as minerals such as folic acid, choline, lecithin, calcium, iron, and selenium. Egg white and egg yolk have different functions and their nutritional values ​​are also quite different. Egg white contains about 12% protein, mainly ovalbumin. The yolk contains more protein, mainly yolk phosvitin. In addition, the fat in eggs is mainly in the yolk, mainly lecithin and cholesterol.

Eggs are not only an important source of high-quality protein, but also rich in many trace elements. The key is that they are easy to digest and absorb without any health burden. They are the preferred healthy food for middle-aged and elderly people, pregnant women and children. In addition, it is not advisable to only eat egg whites and discard egg whites. After all, the main nutritional value of eggs lies in the yolk. In particular, lecithin is an important component of cell membranes and plays an important role in brain development and repair of other organs.

The lecithin contained in egg yolk will make the cholesterol and fat particles smaller and keep them suspended after entering the blood, thus preventing the cholesterol and fat from depositing on the blood vessel walls. Therefore, scientists believe that for elderly people with normal cholesterol, even if they eat 2 eggs a day, the cholesterol in 100 ml of blood will increase by 2 mg at most, which will not cause vascular hardening.

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Studies have shown that moderate egg consumption can increase the levels of heart-healthy metabolites in the blood, which helps reduce the risk of cardiovascular disease. After further exploring 14 metabolites related to heart disease, it was found that compared with people who often eat moderate amounts of eggs, participants who eat less have lower levels of beneficial metabolites and higher levels of harmful metabolites in their blood.

The "Dietary Guidelines for Chinese Residents" (2022 edition) also recommends that adults should consume 40 to 50 grams of eggs per day, equivalent to one egg a day. In fact, through investigations, it was found that many residents in my country did not reach this recommended value. The National Food Safety Risk Assessment Center analyzed the egg food consumption of adult residents in large Chinese cities from 2017 to 2018 and found that the average daily egg food consumption of the entire population was only 28.1 grams, or 3 to 4 eggs per week. The survey data of the Chinese Center for Disease Control and Prevention in 15 provinces in 2015 showed that the median daily egg consumption of the entire population was only 15.3 grams, far below the recommended amount.

Therefore, raising public awareness of the nutritional value of eggs and encouraging moderate consumption of eggs are of great significance for improving the dietary structure of Chinese residents and improving the national health level. In the future, through nutrition education and health promotion, more people will understand and practice the recommendations in the "Dietary Guidelines for Chinese Residents" to ensure a moderate daily intake of eggs, which will help promote the health of the whole people and reduce health problems caused by malnutrition or imbalance. At the same time, for specific groups such as children, pregnant women and the elderly, the importance of eggs as a high-quality source of nutrition should be emphasized, and scientific guidance should be given to them to reasonably match their diet and enjoy the health benefits brought by eggs. While enjoying this ancient and precious ingredient, let us not forget the nutritional value behind it, so that eggs can continue to play an indispensable role in maintaining human health.

References:

Joyce Yongxu Huang, Renwei Wang, Yu-Tang Gao, et al. ABO blood type and the risk of cancer - Findings from the Shanghai Cohort Study[J]. PLoS One, 2017, 12(9):e0184295.

Lang Pan, Lu Chen, Jun Lv, et al. Association of egg consumption, metabolic markers, and risk of cardiovascular diseases: nested case-control study[J]. Elife, 2022, 11:e72909.

Pan Feng, Zhang Tongwei, Mao Weifeng, et al. Analysis of egg consumption status of adult residents in large cities in China from 2017 to 2018[J]. Chinese Journal of Food Hygiene, 2022, 34(6): 1342-1347.