ADEQUATE human nutrition occurs when all factors contributing to food availability and holistic health are present. The absence of any one of these for a period of time, will result in malnutrition of varying degrees.
Available dietary macronutrients, in large amounts, and micronutrients, in far lesser quantities in balanced diets must be absorbed and utilised by the body to prevent nutrient imbalances.
Balanced diets prevent diseases such as diabetes mellitus and heart disease. In such diseases, even if food is available, its utilisation can be impaired.
Some nutritive constituents are converted to immunological substances and protect from infections. Specific vaccines may be more effective when certain nutrients are optimal and vaccination of a significant percentage of a healthy population produces the desired herd immunity.
Some similarities exist in plant and human micronutrient imbalances. “Hidden hunger” in plants due to micronutrient deficiencies are not obvious, yet they reduce crop yield.
Likewise, human micronutrient malnutrition may creep in, seriously impairing function.
While the full impact of Covid-19 on human nutrition is still evolving, hidden hunger in the undernourished and in the obese, both forms of malnutrition, is certainly a matter of grave concern.
Sufficient, safe, toxin-free, nutritious foods appropriate to dietary needs of gender, age, activity and sociocultural preferences must be accessible, affordable and fairly distributed to prevent any form of malnutrition.
Job losses and geopolitical instability also lead to imbalanced diets. Energy-dense foods per se do not assure needed nutrients.
Public health measures safeguard proper absorption and utilisation of essential nutrients.
Health education on diet diversification with a variety of fruits and colourful vegetables like greens and carrots, for example, with exclusive breastfeeding, free school meals and commercial production of nutrient-rich foods support nutritional goals.
Food fortification supplements food with nutrients, and biofortification targets rural areas with restricted market access to fortified or diverse foods.
If micronutrient requirements aren’t affordable by diet alone, high-risk groups benefit from supplementation.
An index of suspicion based on risk groups and, symptoms if present, will detect micronutrient deficiencies early.
Anaemia, low body mass index in women and underweight, wasting and stunting in children reflect undernutrition in general.
Specific micronutrient deficiencies have typical features, often part of the bigger picture of malnutrition.
Groups at risk include the elderly, obese, patients with psychiatric disorders, institutionalised people, indigenous populations, displaced people and alcoholics, but no one is spared.
Monotonous diets of picky toddlers, when creatively corrected, can prevent the tender bones of scurvy. Vitamin C deficiency interferes with development. Babies only on milk that is repeatedly boiled can develop multinutrient deficiencies. Methods of killing bacteria must not destroy milk nutrients.
The B vitamins in a balanced diet prevent anaemia and support nerve integrity. Cross talk with immune cells boost immunity. However, even with adequate diets, gut surgery, for instance, predisposes to deficiencies due to reduced absorption.
Some medications interfere with B6 metabolism and deficiencies can occur secondary to tuberculosis treatment if not supplemented.
Beriberi, a B-1 deficiency, may either be unsuspected or present dramatically with heart failure or muscle paralysis. Nutritional care of pregnant women with severe vomiting, and of nursing mothers, secures the health of generations.
Memory loss, diarrhoea and parchment-like skin of pellagra, a niacin deficiency, still occur in refugee camps that have food insecurity, through aid disruption and unaffordable prices.
Adequate Vitamin A prevents blindness, an important health impact.
Enhancing barrier functions and regulating inflammation, Vitamin A is important for viral defences. Dietary diversification is preventive but provitamin A carotenoid biofortification of staple crops may be necessary.
Vitamin D deficiency is possibly linked to the risk of Covid-19. Its multifunctional role enhances antibody production. Sardines and spinach or fortified foods and sunlight exposure provide it; yet supplementation, in high-risk groups, is essential.
Macrominerals and trace minerals contribute to the quality of one’s life. On a larger scale, they must be in ideal balance for peak human productivity.
The thyroid gland requires iodine for hormone production. With iodine deficiency, symptoms may creep in, such as intolerance to cold, weight gain, constipation and so on. A diet of seafoods, grains and dairy products, avoiding goitrogens like cabbage and cauliflower and salt iodisation prevent mental retardation, miscarriages, stillbirths and birth defects.
Subtle early symptoms of iron deficiency are easily missed if not suspected. Iron biofortification of rice, cassava and legumes with parasite control measures ensure utilisation of dietary iron.
Globally, dietary education on iron enhancement and local foods interfering with iron absorption must also stress dangers of excess iron.
Prioritising quantity and quality of food coupled with holistic, preventive health averts hidden hunger, a pandemic in itself. – September 16, 2020.
* Dr Prameela Kannan Kutty is a Professor of Paediatrics, Universiti Pertahanan Nasional Malaysia.
* This is the opinion of the writer or publication and does not necessarily represent the views of The Malaysian Insight.