The food we eat and the content therein determine the status and levels of what makes up our bodies – minerals, carbohydrates, fat, protein and water.
Therefore, a balanced diet and good nutrition are not only important as a source of energy for our active lives, but are also critical for our defence against diseases.
According to the World Health Organization (WHO), a healthy diet helps protect against malnutrition in all its forms, as well as noncommunicable diseases such as diabetes, heart disease, stroke and cancer.
While there is no specific drug or vaccine for the Covid-19 infection and no food can by itself prevent the infection, a nutritious and healthy diet rich in protective foods can boost one’s immunity and capacity to fight the infection.
Poor diets are associated with poor health
Carbohydrates, proteins, fats, vitamins, minerals, fibre and water are the main groups of nutrients, which together but in variable amounts, make up a balanced diet.
Daily consumption of recommended portions of each of the seven nutrient groups is important for good health.
Therefore, deficiencies, excesses and imbalances in any of these nutrient groups result in various forms of malnutrition.
Malnutrition and poor diets are the leading cause of death and one of the top two risk factors for non-communicable diseases (NCDs) worldwide.
There’s evidence NCDs such as cardiovascular disease, diabetes and cancer, make individuals more vulnerable to infectious diseases such as tuberculosis, malaria, influenza, and pneumonia.
WHO data also suggests that patients with NCDs are 16 times more likely to be hospitalised from contracting Covid-19.
Balanced diet: What proportion of the seven nutrient categories should you eat?
Kenya’s National Guidelines for Healthy Diets and Physical Activity (2017), recommends as follows:
Eat a variety of foods from different groups every day. Include whole or unprocessed starchy foods as part of meals
Eat plenty of green leafy vegetables, red and yellow vegetables and fruits every day and include a variety of other vegetables and fruits.
Eat beans, peas, lentils, cowpeas, pigeon peas, soya, nuts and edible seeds regularly (at least four times a week).
Eat lean meat, fish and seafood, poultry, insects or eggs at least twice a week.
Drink fresh milk, fermented milk or yoghurt every day.
Use oil or fat in moderation in meals. Limit the amount of solid fat and use fortified oil.
If you use sugar, use it sparingly.
Use iodised salt but use it sparingly.
Drink plenty of safe water.
The food pyramid is a visual representation of the foods that should make up the basics of a healthy diet in the base and the foods that should be consumed sparingly in small amounts at the top.
The pyramid presented below is an adaptation of the nutritional recommendations about the main food groups by the Food and Agriculture Organization of the United Nations aimed at improving citizens’ health and prevention of NCDs through the food-based dietary guidelines.
A healthy diet should contain proportionate amounts of the various food groups as indicated by the number of servings.
Increase servings of protective foods for better health and defence from disease infections.
Protective foods including fruits, vegetables, legumes, seeds, nuts and whole grains contain substantial amounts of vitamins, minerals, micronutrients and other beneficial phytochemicals.
Examples of protective foods, constituents and health benefits are shown in the table on the right.
As shown in the table, protective foods can boost immune function and lower NCD risks. Therefore, adopting protective diets can significantly contribute to lower incidence, morbidity and mortality of Covid-19 and similar infectious diseases.
These foods, however, are generally under-consumed globally and this has a significant negative impact on global health.
According to Kenya’s Ministry of Health, only 2.5 million Kenyans (6 per cent), consume the recommended amounts of fruits and vegetables.
Low consumption of the two has been aggravated under Covid-19 due to various reasons including less physical and economic access to these food commodities.
The WHO recommended daily intake is at least 400g, or five portions (80g each) of diverse fruits and vegetables.
There is need to devise strategies at the global, national and household levels to increase use of the recommended amount of fruits, vegetables, nuts, whole grains and other nutritious foods.
Healthy diets that are rich in vitamins, minerals, fibre and other health-promoting phytochemicals can boost immunity and the capacity to fight infectious agents including Covid-19.
Besides increasing our consumption of protective foods, we must drink clean water regularly and stay well-hydrated.
Drinking ample amounts of water and fluids (at least eight glasses a day for adults) also helps our immune system.
Ambuko is an Associate Professor of Horticulture and Postharvest Specialist, Department of Plant and Crop Protection, University of Nairobi. Mehrdad Ehsani is the managing director and Milani Peiman,consultant, Food Initiative of the Rockefeller Foundation.