Egg yolks and egg whites differ in more ways than just colour. The yolk contains fat and cholesterol whilst the white consists of nothing but good nutrients.
But do you have to avoid eating the yolk, and are egg yolks bad for you? We explain why you can – and should – enjoy the entire egg!
Does it make sense to eat egg yolks? Health fanatics usually only eat egg whites. But what about you?
Do you have to avoid the yolk too? What is the real difference between the yolk and the white? We compare the two, based on medical advice from the SA Food Data System
What’s in an egg white?
Fewer kilojoules: At only 100 kJ per egg, egg whites are a nutritional powerhouse. If you divide a slice of bread into three squares, the egg white amounts to the same amount of kilojoules as one square.
6g protein: One whole egg has 14g protein, so a little less than half the protein is in the white. You need 40-50g of protein per day.
No fat: The only fat in an egg white is the fat you add when you cook it in oil or if you eat it with butter, mayonnaise, margarine, cheese or bacon. If you opt for a boiled or poached egg or choose to scramble it in the microwave without adding any oil or butter, no fat is involved.
No cholesterol: Egg whites are cholesterol-free.
Good nutrients: Egg whites also provide you with:
- Folate (good for brain power)
- Selenium (helps to protect you from cancer)
- Sulphur (important for metabolism)
- Magnesium and calcium (good for your skeleton)
What about sodium?
One egg white has 55mg sodium, but it’s considered healthy to consume up to 1 500mg of sodium daily. The small amount of sodium in an egg white is not enough to be detrimental to you – unless you add loads of salt.
What’s in an egg yolk?
310 kilojoules: Basically the same as a slice of bread. But an egg yolk is much more nutritionally desirable than a slice of bread!
Protein: At 8g, an egg yolk contains more protein than the white. One whole egg (yolk and white combined, or 14g) provides you with a third of the amount of protein you need daily. One whole egg has the same amount of protein, gram for gram, as steak! Because an egg contains all the amino acids we need, it is classified as a complete protein.
Your body cannot function without cholesterol as it is extremely important for your hormones and for maintaining your cell membranes
Cholesterol: One egg has 160mg cholesterol. Which sounds extremely high for those of us who are obsessed with the effects of cholesterol.
However, what we eat ultimately makes a small difference to our cholesterol levels. In fact, dietary guidelines no longer have specific limits on the amount of cholesterol we should be eating, but rather limit how much saturated fat we should eat. Your body cannot function without cholesterol as it is extremely important for your hormones and for maintaining your cell membranes.
Fats: There is 4,5g fat in an egg yolk. But don’t lose perspective: 4,5g is not a lot, and most of it is healthy, good fat.
- Vitamin D: An egg yolk contains about 18 I.U. You need 30 times more per day (600 I.U.) but vitamin D is scarce in the food we eat, with eggs, cheese, liver and fatty fish being almost the only source of vitamin D in our diets.
- Minerals: Instead of taking a mineral supplement, you might just as well eat egg yolks more often because it provides iron, magnesium, sulphur, potassium, calcium and even zinc.
- Extra nutrients: Egg yolks are also a source of biotin, lutein and zeaxanthin.
Go ahead, enjoy the yolk
Egg yolks don’t contain a lot of fat or kilojoules but they are nutrient-dense food. In addition to that, eating egg yolks only has a small effect on the cholesterol levels of healthy people. An egg a day is good for you!
This article first appeared in rooi rose magazine.
While All4Women endeavours to ensure health articles are based on scientific research, health articles should not be considered as a replacement for professional medical advice. Should you have concerns related to this content, it is advised that you discuss them with your personal healthcare provider.