Examination of micronutrient intake is important – vitamins and minerals that are essential in tiny amounts but have enormous effects on our growth, development, immunity, brain function and physiological homeostasis.
The spectrum of hidden hunger :
Multiple micronutrient deficiencies are now global public health problems. The deficiency of more than one micronutrient such as vitamin A, vitamin D, zinc, folate, iron, and vitamin B12 is referred as ‘hidden hunger’. As the name implies, micronutrient deficiencies don’t cause a physical hunger, but can bring devastating toll on our physical, mental, and cognitive health. According to the World Health Organization (WHO), iron and vitamin A deficiencies are most common around the world, especially among children and pregnant women. WHO also estimated that around two billion global population lacks adequate micronutrients.
Globally 40% pregnant women suffers from iron or vitamin B12 deficiency anemia. A 2017 study found that 50% adolescent Indian girls were anemia. Vitamin A deficiency (VAD) leads to night blindness and a more severe deficiency may lead to permanent blindness. The Comprehensive National Nutrition Survey conducted during 2016-18 found VAD in India was 17.54% and children who received exclusive breastfeeding had lower prevalence of VAD.
Vitamin D deficiency remains a global public health challenge and has reached epidemic proportions. A serum 25(OH) vitamin D level of less than 20 ng/mL is considered vitamin D deficiency, while a level between 21 and 29.9 ng/mL is considered vitamin D insufficiency.
Micronutrients and their overall functions
Micronutrients include vitamins and minerals, which are further divided into water-soluble vitamins, fat-soluble vitamins, macro-minerals, and microminerals. Water-soluble vitamins are dissolved in water and excreted through the urine if consumed in excess. Vitamins B, C, and P are water-soluble vitamins with unique functionality in carrying multiple physiological functions. B vitamins including B1, B2, B3, B5, B6, B7, B9, and B12 play vital role in converting nutrients into energy, synthesis of fatty acids, cell formation, cell division, cell functions, metabolism, and absorption of nutrients. These functions are fundamental and exclusive. Vitamin C on the other hand is an excellent antioxidant and helps scavenge free radicals produced from chronic stress.
This vitamin is also crucial to maintain optimum skin health, production of neurotransmitter, and collagen.
Fat-soluble vitamins i.e vitamin A, D, E, and K are soluble in fats and are stored in liver for future use. Vitamin A as retinols and carotenoids is crucial to promote proper vision, vitamin D is needed for optimum immune function, bone health, and overall health. Vitamin E is a potential antioxidant to protect cell damages and imperative for hair and skin health. Vitamin K is need for blood clotting and bone growth.
Macro-minerals are the minerals that are need in larger amount than micro or trace elements. Calcium, phosphorus, magnesium, sodium, potassium, chloride, and sulfur are the major macro-minerals.
Micro-minerals are needed in smaller amount and thus known as trace elements. These minerals are iron, manganese, zinc, selenium, copper, and iodine.
A list of micronutrients, their food sources and recommended daily allowance is provided below.
|
Micronutrient |
Food Sources |
Recommended Daily Allowance for adults
(Milligram, micrograms,International Unit) |
| Water-soluble vitamins | ||
| Vitamin B1 | Meat, fish, organs, whole grains | 1.1-1.2 mg |
| Vitamin B2 | Organ meats, milk and milk products, eggs | 1.1-1.3 mg |
| Vitamin B3 | Fatty fish, green leafy vegetables, beans | 14-16 mg |
| Vitamin B5 | Beef, chicken breast, avocado, mushrooms, nuts, seeds, dairy, fortified cereals, organ meats | 5 mg |
| Vitamin B6 | Tuna, chickpeas, poultry, salmon, dark green leafy veggies, banana, papaya, orange, carrot, milk | 1.3 mg |
| Vitamin B7 | Eggs, avocado, sweet potato, nuts, seeds, pork, salmon, spinach | 30 mcg |
| Vitamin B9 | Dark green leafy veggies, beans, peanuts, sunflower seeds, fresh fruits, seafood, liver, whole grain | 400 mcg |
| Vitamin B12 | Seafood, fish, meat, milk, cheese, eggs, fortified cereals | 2.4 mcg |
| Vitamin C | Citrus fruits such as lemon, orange; peppers, strawberries, broccoli, potatoes, brussels sprouts | 75-90 mg |
| Fat-soluble vitamins | ||
| Vitamin A | Cheese, liver, salmon, cord liver oil, fish, cooked carrot, sweet potato, raw spinach, lettuce | 700-900 mcg |
| Vitamin D | Sunlight, fish oil, milk | 600-800 IU |
| Vitamin E | Sunflower seeds, almonds, peanuts, beet greens, spinach, pumpkin, red bell pepper | 15 mcg |
| Vitamin K | Green leafy veggies, soybeans, broccoli, cabbage | 90-120 mcg |
| Macro-minerals | ||
| Calcium | Milk and other dairy products, dark green leafy vegetables, broccoli | 2000-2500 mg |
| Magnesium | Beans, legumes, whole grains, dark green vegetables, soybeans, lentil, nuts | 310-420 mg |
| Sodium | Salt, processed foods, canned soup | 2300 mg |
| Potassium | Lentils, coconut water, banana | 4700 mg |
| Phosphorus | Dairy, red meat, seafood, poultry, legumes, nuts | 700 mg |
| Microminerals | ||
| Iron | Nuts, dark leafy green vegetables, oats, tofu, iron-fortified cereals | 8-18 mg |
| Copper | Organ meats, shellfish, fish, nuts, seeds, whole grains | 900 mcg |
| Iodine | Fish, shellfish, dairy, eggs, chicken, beef liver | 150 mcg |
| Zinc | Meat, fish, seafood, legumes, seeds, nuts, dairy | 8-11 mg |
| Selenium | Seafood, organ meats, Brazil nuts, poultry, eggs, red meat, cereals | 55 mcg |
| Manganese | Shellfish, oatmeal, nuts, spinach, legumes, brown rice | 1.8-2.3 mg |
Source: National Institute of Health
Micronutrients in health prevention and promotion:
Deficiency and insufficiency of micronutrients have a major impact on organ system function and health outcomes. Micronutrient deficiency is found to be linked with heart failure according to multiple observational studies. Heart failure patients were associated with micronutrient deficiencies such as vitamin A, calcium, magnesium, selenium, iodine, and vitamin D as reported by these studies
The results of myriad of research studies confirms the importance of consuming micronutrients in optimum quantity to promote and prevent overall health
Diet and supplements:
Consuming a variety of essential foods such as fruits, vegetables, leafy greens, whole grains, eggs, fish, lean chicken, soybeans, beans, legumes, nuts, and seeds is the most effective way to ensure optimum vitamin and mineral intake. Ensure you are eating antioxidant-rich foods. Take advantage of an array of fresh, seasonal fruits and vegetables rather than relying on one fruit or vegetable.
For example, if an adult needs 1800 calories per day, a well-rounded diet includes two cups (250 grams) of green leafy vegetables, one cup (150 g) of red and orange vegetables such as beets, carrots, and pumpkin, and two cups (250 g) of cruciferous vegetables like broccoli, cabbage, cauliflower, 1.5 cups (150 g) cooked whole grains like quinoa, brown rice, millets; 60-120 g proteins from seafood, meat, poultry, eggs, nuts, seeds, soy and around 30 g of cold-pressed cooking oil such as ground nut, coconut, olive. Protein requirements depend on level of physical activity, physical activity and physiological condition.
A qualified nutritionist or registered dietitian can customize your diet.
Supplements on the other hand is required to manage severe micronutrient deficiency but always consult a physician about dosage and frequency to avoid excessive consumption and toxicity. It’s always safest to eat natural foods. Avoid flashy products touting ‘super’, ‘mega’, ‘loaded’, ‘high’ on their labels.
To put it simply, micronutrients play just as significant a role as macronutrients. Vitamin and mineral deficiencies can affect our health at a cellular level. Symptoms can be generalized and ignored by most. Be aware of chronic fatigue, headaches, weakness, joint pain, or frequent colds. Eat local, eat variety to prevent micronutrient deficiency and maintain overall health.
