Everything you need to know about eggs

Eggs have been eaten by humans for thousands of years. The female animals of many different species produce eggs, but by far the most common choice for consumption is the egg of the chicken.

Eggs contain many vitamins and minerals that are essential parts of a healthy diet, and in many parts of the world, eggs are a readily available, inexpensive source of food.

The United States is regarded as the world's largest exporter of eggs. In fact, in 2017, the per capita consumption is expected to be 275.8.

Here we provide a nutritional breakdown for eggs, an in-depth look at their possible health benefits, tips on how to incorporate more eggs into your diet, and the potential health risks of consuming them.

Fast facts on eggs:

• Eggs are considered to be one of the best sources of protein available.
• Around 9 percent of an egg's content is fat, found almost exclusively in the yolk.
• Eggs are known for containing cholesterol.
• They are one of the most commonly consumed animal products in the world.

Benefits

Nutrients contained within eggs are beneficial for brain cells and promote healthy brain function.

There are several health benefits that can be derived from eggs, including:

• Strong muscles: The protein within eggs helps keep muscles working well while slowing the rate at which they are lost.
• Brain health: Eggs contain vitamins and minerals that are needed for the regular functioning of cells, including the brain, nervous system, memory, and metabolism.
• Good energy production: Eggs contain all the daily vitamins and minerals that are needed to produce energy in all the cells of the body.
• A healthy immune system: Vitamin A, vitamin B-12, and selenium are key to keeping the immune system healthy.
• Lower risk of heart disease: Choline plays an important part in breaking down the amino acid homocysteine, which is associated with the development of heart disease.
• Healthful pregnancy: Some nutrients within eggs help to prevent congenital disabilities, such as spina bifida.
• Eyesight: Lutein and zeaxanthin help to prevent macular degeneration, the leading cause of age-related blindness. Other vitamins also promote good vision.
• Weight loss and maintenance: The high quality of protein within eggs might help keep people energized and feeling fuller for longer. Feeling full prevents snacking, which reduces overall calorie intake.
• Skin benefits: Some vitamins and minerals within eggs help promote healthy skin and prevent the breakdown of body tissues. A strong immune system also contributes to a healthy look overall.

The health benefits of eggs can only be experienced when they form part of a balanced diet.

Nutrition

Below is a list of nutrients found in eggs:

• vitamin A
• vitamin B-2
• vitamin B-12
• vitamin B-5
• vitamin D
• vitamin E
• biotin
• choline
• folic acid
• iodine
• iron
• lutein and zeaxanthin
• phosphorus
• protein
• selenium

Protein

A medium-sized egg weighing 44 grams typically contains 5.53 grams of protein. Around 12.6 percent of the edible portion of an egg is protein, and this is found both in the yolk and the egg white.

Fats

One large egg contains about 5 grams of fat. The majority of fat in an egg is unsaturated and is regarded to be the best type of fat to be included in a balanced diet. Saturated fats should be limited to less than 10 percent of your daily calories. For example, a diet consisting of 1,800 calories should limit saturated fat to no more than 20 grams. A large egg contains less than 2 grams of saturated fat.

Omega-3 fatty acids

Eggs are also a rich supply of omega-3 fatty acids. These are predominantly in the form of docosahexaenoic acid (DHA), which helps with the maintenance of brain function and normal vision.

These fatty acids are most commonly found in oily fish, and so eggs provide an alternative source for people that are unable to eat fish.

Eggs and cholesterol

One medium-sized egg that weighs 44 grams typically contains 164 milligrams of cholesterol. However, evidence has shown there is little, if any, relationship between cholesterol found in food and heart disease or blood cholesterol levels.

As eggs are low in saturated fats, the effect that they have on blood cholesterol is deemed to be clinically insignificant.

Diet

Huevos rancheros is a simple recipe that can incorporate eggs into your diet, the accompanying tomatoes and vegetables make it an overall balanced meal.

Eggs are a versatile food that can be prepared in many different ways, such as frying, hard boiling, poaching, scrambling, and baking. This makes eggs quite simple to incorporate into a diet.

Here are a few examples of meals that can be made using eggs. Some of these are naturally healthier than others:

• omelet
• huevos rancheros
• pancakes
• kedgeree
• quiche

Eggs can be used as snacks, with hard-boiled eggs being a popular option, and even served as a party or picnic food, such as with deviled eggs. This makes eggs quite adaptable to many lifestyles.

Risks

The following possible health risks are associated with the consumption of eggs:

• Bacteria: People are advised to avoid eating raw or undercooked eggs. Bacteria can enter the egg through pores in the shells. In the U.S., all eggs graded by the U.S. Department of Agriculture (USDA) are washed with a sanitizing rinse during the screening stage at a processing plant.
• Pasteurization: In the U.S., egg products are also required by law to undergo a process called pasteurization. During this process, eggs are rapidly heated and kept at a high temperature for a period of time to kill off any Salmonella bacteria.
• Storage and cooking: Eggs should be avoided if their shells are cracked or if they are past expiration date.

Most advisory bodies recommend that eggs are stored in the refrigerator. The USDA state that if eggs are left out at room temperature they can sweat, making it easier for bacteria to move into the egg and grow. When cooking eggs properly, they must be cooked thoroughly until the yolks are firm. Scrambled eggs, for example, should not be runny.

It is best not to put all your eggs in one basket; it is the total diet or overall eating pattern that is most important in disease prevention and achieving good health. It is better to eat a varied diet than to concentrate on individual foods as the key to good health.

If you enjoyed reading about the potential health benefits of eggs, take a look at our collection of articles about other foods.