Healthy dietary habits begin early in life. Breastfeeding provides additional benefits such as healthy growth, cognitive development, and possibly further protection against obesity and noncommunicable diseases. Energy intake (calories) should be in balance with energy expenditure. To prevent unhealthy weight gain, energy from fat should not exceed of total calories consumed. Saturated fat should be no more than of total energy intake, and trans fat should be below %1. 

For a healthy diet, energy from free sugars should be less than of total energy intake. A ratio less than %5 is recommended due to additional health benefits. Keeping salt intake below 5 grams per day is necessary to prevent hypertension and reduce the risk of heart disease and stroke. 

In addition to playing an important role in ensuring normal body function and a healthy body, a balanced diet is also necessary for a strong immune system and the fight against viral infections. The antiviral effect is sometimes part of the defense mechanism in the fight against the virus; Sometimes it occurs as an increase in cell activity involved in the immune response to the virus. 

The usefulness of nutrition containing vitamins, minerals, fatty acids, some polysaccharides such as glucose and starch, and auxiliary substances such as polyphenols in olive oil has been shown. These substances can be effective against the virus directly or by strengthening immunity. For example, vitamins A, D, E and C are critical for the development of immune-boosting mechanisms. Most vitamins are powerful antioxidants. They reduce oxygen radicals that will increase oxidative stress in the body. While the importance of vitamin D level has previously been shown in viral diseases such as hepatitis C and the common cold, the relationship of its deficiency with the severe clinical course of COVID-19 has been shown in repeated studies.

Zinc, selenium, iron and chromium should be taken to strengthen immunity. In addition, the benefits of foods rich in plant products such as polyphenols, phalavonoids, alkaloids, thiophene, terpenoid tannin and lignin have been shown due to the antioxidant, antiviral, anticancer and anti-inflammatory (inflammation-reducing) effects of these substances.