The main forms of micronutrient deficiencies in Kenya include vitamin A, iron, folate, vitamin B12, iodine, and zinc deficiencies.So, where can these essential vitamins and minerals be found, and why are they necessary for the body?
Vitamin A:Vitamin A comes as either the preformed kind, which can be used directly in the body, from liver, milk (also breast milk), egg, butter, and fish liver oils. Or as the provitamin A carotenoids, which can be converted into vitamin A in the body after its consumption, from: dark-green leafy vegetables (e.g. spinach, broccoli, green beans) and red, yellow or orange-coloured fruits and vegetables (e.g. sweet potato, pumpkin, carrots, peppers, mangos, papaya, tomatoes).
Several factors can affect the bioavailability of Vitamin A in the body: Protein-energy malnutrition, zinc deficiency, dietary fat (vitamin A is one of the fat-soluble vitamins together with vitamin D, E and K) as well as infections.
Vitamin A is also an antioxidant and plays an essential role for humans when it comes to vision, normal cell growth and development (maintenance of the heart, lungs, kidneys and other organs as well as red blood cell development), and immune function. When the body lacks sufficient amounts of vitamin A, it is more exposed to getting serious infections with a higher mortality risk. Vitamin A deficiency is a public health problem in more than 100 countries in the world, Kenya included, typically seen in infants and young children. Some of the early signs of vitamin A deficiency is night blindness or reduced eye adaptation do darkness as well as dryness of the skin and eye discomfort. Vitamin A deficiency is one of the top causes of preventable blindness in children. Furthermore, a vitamin A deficiency in pregnant or lactating women leads to increased risk of maternal or infant sickness and mortality, anaemia, and slower infant growth and maturing.
Iron:Iron deficiency is very common in women in the reproductive age due to their iron losses through menstrual bleeding. During pregnancy the woman’s iron is transferred to the fetus, also increasing women’s iron need. The iron requirement is especially high in infants and young children (6-24 years old) and adolescents (12-16 years old) due to their rapid growth rates.
In order to increase the body’s absorption of iron from the diet, one can include vitamin C rich food (e.g. peppers, oranges, lemons, berries) together with the iron rich meal, as vitamin C helps the body absorb iron. Meat, fish and chicken also contain the so-called MPF-factor (Meat-Protein-Factor), which increases iron absorption. On the contrary, calcium from dairy products inhibits the iron absorption and should not be consumed at the same time as the iron rich meal.
Dietary iron comes in two forms: Haem (more efficiently absorbed) and non-haem iron. Plants and iron-fortified foods contain the non-haem iron: Beans (soy, kidney, edamame, chickpeas), nuts, dried fruit, cacao, chia, grains like millet and sorghum. Animal products contain the haem iron: Meat, seafood, poultry.
Iron functions as a component of haemoglobin, which is a red blood cell that transfers oxygen from the lungs to the tissues in the body, where iron forms the oxygen-binding part. In general, iron takes part in many metabolic pathways transferring oxygen in the liver, brain and muscle tissue. Thus, iron is necessary for physical growth, neurological development, and cellular functioning.
Folate: Folate is also known as the water soluble vitamin B9 and is the general term of compounds including folic acid and similar derivatives. Folate is found in many foods with high amounts in liver, green vegetables (spinach, asparagus, broccoli), legumes, fruits and berries, nuts, seafood, eggs, dairy products, meat, chicken, and grains like millet.
Folate works as a coenzyme in the synthesis of DNA and RNA as well as the metabolism of amino acids. Hence, folate is essential for cell division and the formation of red blood cells. Folate deficiency can lead to anaemia with symptoms including weakness, fatigue, difficulty concentrating, and shortness of breath. Furthermore, women with folate deficiencies are at higher risk of having infants with brain and spinal cord defects (neural defects) and fetal growth retardation.
Vitamin B12: Vitamin B12 is mainly found in animal products. Good sources for vitamin B12 are meat, liver, dairy products, eggs, and fish and seafood. Thus, a very little animal product intake may increase one’s risk of developing a vitamin B12 deficiency.
Getting a sufficient amount of vitamin B12 is necessary for the body’s DNA formation, normal red blood cell formation and neurological function (the central nervous system). Vitamin B12 deficiency leads to anaemia as well as a high risk of degeneration of the brain, spinal cord, optic and peripheral nerves causing neurological damage. In pregnant women, a B12 deficiency can lead to damage in the central nervous system (neural tube defects), development delays, and anaemia in the newborn.
Iodine: Iodine deficiency is one of the most widespread nutritional disorders in the world, resulting in an abnormal enlargement and possible dysfunctioning of the thyroid gland. An impaired synthesis of thyroid hormones (normally regulating growth) will lead to issues with intellectual development and physical growth. This has led to an increased fortification of salt with iodine in several countries, Kenya included. However, an iodine deficiency problem is still seen in rural areas in Kenya due to lack of education in how to store and use the salt (should be stored with a cover in a dry place) as well as less availability of iodised salt.
During pregnancy and lactation, it is recommended for the woman to take an extra supplement of iodine (25-50 μg/d) in order to provide sufficient amounts to cover the foetus’ needs (also through the breastmilk) and secure maternal thyroid gland function.
Iodine can be obtained from milk, fish and seafood, and eggs, however the iodine content varies highly depending on the iodine content in the environment. The amount of iodine is higher in sea-plants compared to plants on land, and the iodine in milk products depends on the amount of iodine in the animal feed and the use of iodine containing disinfectants just before milking. Likewise, the iodine content in eggs depends on the iodine concentration in the chicken feed. A last source of iodine is through drinking water, yet the amount varies between different locations.
Zinc: Zinc plays an essential part in more than 300 enzymes involved in the synthesis and metabolism of proteins, fats, carbohydrates, and some vitamins including vitamin A. Zinc plays an utmost important role in a well-functioning immune system as well as in normal DNA-formation and cell divisions. Furthermore, zinc ensures protection of proteins and fats from being damaged by oxidative stress. In addition, zinc is related to maintenance of normal bone density, cognitive function, and vision. A severe zinc deficiency is characterised by growth retardation, delayed maturation, skin lesions, hair loss, and behavioural disturbances. Thus, infants and growing children/adolescents as well as pregnant/lactating women are in need of higher amounts than the normal adult.
High food sources of zinc are meat, milk and milk products, whole-grain cereals, grains like sorghum, cacao, eggs, cashew nuts, seafood, and chia. However, phytic acid is naturally present in grains, cereals and legumes and inhibits the zinc (as well as the iron and calcium) absorption by binding to the minerals. Ways to prevent this is by soaking the grains/legumes, or by the most commonly used milling process that removes the phytic acid from grains. Another way to ensure a high zinc absorption from the ingested food is by getting the zinc from animal-based sources. In general, the amount of absorbed zinc increases with an increased zinc intake. Omega-3: Omega-3 polyunsaturated fatty acids (Omega-3) and omega-6 polyunsaturated fatty acids (Omega-6) are the two essential fatty acids the body needs from the diet to survive, as these cannot be produced by the body itself. These play an important role in the growth of the brain, development of the nervous system and cell membranes as well as visual function, immune and inflammatory responses, and in the body’s physiological functions and production of hormones that regulate blood clotting, inflammation and contraction/relaxation of the arteries (blood pressure). A deficiency of the essential fatty acids are shown by skin, hair and nail problems, joint pain, and growth retardation. It has been shown that omega-3 can help prevent heart disease and stroke, thus playing an essential role in ensuring good health. Furthermore, a woman’s intake of omega-3 during pregnancy and lactation will improve the omega-3 status of the infant and ensure normal growth and development.
Omega-6 can be found in many vegetable oils (e.g. sunflower oil, rapeseed oil, peanut oil, margarine) as well as in nuts and seeds, thus it is normally easy to get through the diet. On the contrary, having a diet with an insufficient amount of omega-3 is more common, thus a general focus should be put here. It is known that in countries like Kenya that have low economic status, the consumption and availability of omega-3 rich foods are limited for the poor part of the populations. Thus, an introduction to omega-3 rich foods plays an important role in addressing malnutrition with nutritional deficiencies here.
There are three main omega-3 fatty acids, and the most common one is found in plant foods: Chia seeds and oil, flaxseed oil, hemp seeds, walnuts, soybeans and oil, and canola oil. The other two kinds of omega-3 fatty acids are mainly found in fish (mackerel, cod, salmon, herring), fish oils, and seaweed. Chia is one of the best sources of plant omega-3 containing around 19 g/100 g chia and with an additional high content of both protein, fiber, calcium, iron, folate, zinc, and magnesium. This is why an introduction of chia seeds in the diet of the Kenyan population is a step towards reducing malnutrition in Kenya.