Blueberries in garden

According to Adela Mora-Gutierrez, Ph.D., a research scientist in food science in Prairie View A&M University’s College of Agriculture and Human Sciences, humans need to eat highly nutritious foods to fight COVID-19. She says two of the most highly nutritious foods found in nature are blueberries and flaxseed. Mora-Gutierrez details other methods for strengthening the immune system in the global fight against COVID-19.

Which populations are at a higher risk of serious illness from COVID-19?

Individuals aged 65 years and older and individuals with chronic respiratory conditions, such as asthma, are at a higher risk of serious illness from COVID-19.  But high antioxidant, flavonoid, and fiber intake associated with a plant-based diet can help manage asthma. This could be helpful for many vulnerable people during this pandemic.

Which nutrients can help boost the immune system?

Vitamin C, or ascorbic acid, is an essential nutrient for man because Homo sapiens [humans] lack an enzyme called L-gulonolactone oxidase, which is present in many animal species. Vitamin C deficiency causes impaired immunity and a higher susceptibility to infections.

Which foods are high in vitamin C?

Blueberries are high in vitamin C. The flavonoid content and antioxidant capacity of blueberries are also very high.  Therefore, the dietary intake of blueberries is essential for a normally functioning immune system in young, adult, and elderly populations. It is also useful for improving lung function in asthma patients.

What should people who follow a plant-based diet do to ensure they stay healthy?

If you stick to a plant-based diet, it is important to get vitamin D through fortified plant-based milk and by spending 30 minutes in the sunshine each day.

Moreover, fatty acids of the omega-3 series also have been regarded as essentials.  One fatty acid called Linolenic acid (ALA) is found in the leaves of many plants and some seeds.  Omega-3 fatty acids like ALA boost the immune system by enhancing the functioning of immune cells.  In sick individuals, there is not an adequate cell membrane content of omega-3 fatty acids.

What else can help boost the immune system?

Probiotics can help to boost the immune system.  If you catch COVID-19, probiotics may help reduce the severity of your symptoms.  Fermented dairy products with active bacterial cultures are one of the most common sources of probiotics.  Probiotics can also be consumed in supplement form.

Which other supplements can help?

The reduction in immune competence seen in various catabolic states may be due to zinc deficiency.  Zinc can be consumed in supplement form. Typically considered a threat to the lungs, COVID-19 also presents a significant threat to heart health.  Although supplements cannot cure or prevent COVID-19, the consumption of probiotics and zinc supplements will improve immune response in all age groups.

What happens if the proper nutrients are not consumed?

We know that almost every aspect of the body’s defense can be compromised by malnutrition.    Zinc is so crucial to immunologic function that deficiency of this substance alone can be lethal to both humans and animal systems.  Vitamins are also essential elements in the biological balance necessary for proper immune functioning.  A study of vitamin A deficiency reported that this state is associated with a decreased number of lymphocytes in the spleen and peripheral blood and reduced responsiveness to mitogens.  When vitamin A is restored in the diet, the immunodeficiency was corrected.

In conclusion, foods modulate immune function.  One group of foods represented by probiotics stimulates innate immunity, while other foods, including vitamins and minerals, activate acquired immunity.  To strengthen the immune system quickly, it is recommended to eat a diet rich in fruits and vegetables, exercise regularly, maintain a healthy weight, drink alcohol, preferably red wine, in moderation, do not smoke, get enough sleep, and take steps to avoid infection, such as washing hands frequently and cooking eggs and meats thoroughly.

Adela Mora-Gutierrez, Ph.D., a research scientist in food science in Prairie View A&M University’s College of Agriculture and Human Sciences