Hidden Hunger

Definition and Concept

Hidden Hunger is a term used to describe micronutrient malnutrition.
It refers to a state where an individual may have adequate or even excessive energy (calorie) intake but suffers from a deficiency of essential vitamins and minerals,.
These deficiencies are often "hidden" because they may not manifest with overt clinical signs of malnutrition (like wasting or edema) until they are severe, yet they compromise health, survival, and development,.
Micronutrients are required by the body in minute quantities (less than 100 mg/day or <0.01% of body weight) but are critical for enzyme function, gene activation, and immune defense,,.
It is considered a major component of the "Triple Burden of Malnutrition" (alongside undernutrition and obesity),.

Dietary Quality: The primary cause is a diet heavily reliant on staple crops (cereals) which are energy-dense but low in micronutrients, with low consumption of animal-source foods, fruits, and vegetables,.
Complementary Feeding Gap: Complementary feeding is identified as the "weakest link" in child nutrition; introducing dilute, starch-based diets without vegetables or animal proteins leads to rapid depletion of iron and calcium stores by 6 months of age.
Bioavailability Issues:
- Vegetarian diets often contain non-heme iron which has low bioavailability (5%) compared to heme iron (35%).
- Presence of inhibitors like phytates (in cereals) and oxalates reduces the absorption of minerals like iron, zinc, and calcium,,.
- Excessive intake of cow’s milk can hinder iron and calcium absorption due to high phosphate content,.
Losses and Increased Demand:
- Recurrent infections (diarrhea, pneumonia) deplete micronutrient stores,.
- Parasitic infestations (e.g., hookworm) cause blood and nutrient loss.
- Preterm and Low Birth Weight (LBW) infants have lower stores at birth.

While many micronutrients are essential, specific deficiencies are highlighted for their public health impact.

Prevalence: It is the most common micronutrient deficiency globally and in India,. NFHS-5 data indicates 67% of children (6-59 months) are anemic,.
Impact:
- Leading cause of nutritional anemia.
- impairs physical stamina, concentration, and work efficiency.
- Lowers IQ by approximately 9 points and causes irreversible changes in brain dopamine receptors,.
- Contributes to 20% of maternal deaths.
Sources: Heme iron (liver, meat) is better absorbed than non-heme iron (greens, jaggery, dates),.

Impact: Iodine is critical for thyroid hormone synthesis and early brain development.
Spectrum: Iodine Deficiency Disorders (IDD) range from goiter and hypothyroidism to cretinism and permanent mental retardation,.
Cognitive Loss: Even mild deficiency can lower a child's IQ by 10–13.5 points,.
Etiology: Soil depletion in mountainous and flood-prone regions leads to low iodine in crops.

Impact:
- Leading cause of preventable childhood blindness,.
- Reduces epithelial integrity and immunity, increasing morbidity and mortality from diarrhea and measles,.
Clinical Features: Night blindness, Bitot’s spots, corneal xerosis, and keratomalacia.
Epidemiology: Continues to be a public health problem in backward pockets, although florid deficiency is declining.

Impact:
- Essential for growth; deficiency causes stunting and hypogonadism,.
- Impaired immunity leads to increased susceptibility to diarrhea and pneumonia,.
Clinical: Acrodermatitis enteropathica (periorificial dermatitis), alopecia, and loss of taste (hypogeusia),.
Context: Often seen in association with PEM and chronic diarrhea.

Impact:
- Megaloblastic anemia and neural tube defects in the fetus,.
- Vitamin B12 deficiency is emerging as a significant problem in strictly vegetarian populations and breastfed infants of vegan mothers,.
- Associated with neurological developmental delays and infantile tremor syndrome.

The impact of hidden hunger is pervasive, affecting the individual across the life cycle and the nation's economy.

Mortality and Morbidity:
- Contributes directly or indirectly to child mortality (e.g., severe anemia, reduced resistance to infection).
- Increases the severity of common childhood illnesses like diarrhea and measles.
Growth and Development:
- Stunting (low height for age) is a hallmark of chronic hidden hunger (zinc, protein, energy).
- Impaired cognitive development and school performance reduce the human resource potential,.
Economic Impact:
- Reduced work capacity in adults (due to anemia).
- Loss of GDP due to lower productivity and healthcare costs.
Fetal Programming: Maternal micronutrient malnutrition (e.g., B12, folate) affects fetal growth and may program the fetus for adult-onset diseases like diabetes and cardiovascular disease (FOAD hypothesis),.

A multi-pronged approach involving medical, dietary, and public health interventions is required.

Rainbow Revolution: Encouraging the consumption of "GYOR" foods (Green, Yellow, Orange, Red vegetables and fruits) to ensure adequate intake of antioxidants and vitamins,.
Dietary Modification:
- Promoting the intake of cereals, pulses, vegetables, and animal products.
- Using food processing techniques like sprouting, fermentation, and soaking to reduce phytates and improve bioavailability.
- Improving complementary feeding practices to include nutrient-dense foods.

Vitamin A Prophylaxis: Massive dose (100,000–200,000 IU) given every 6 months to children 9 months to 5 years,.
Anemia Mukt Bharat: Iron and Folic Acid (IFA) supplementation for children, adolescents, and pregnant/lactating women,.
Zinc Supplementation: Used therapeutically in diarrhea (20 mg for 14 days) to prevent recurrence and restore stores,.
Iodine: Supplementation in endemic areas where salt iodization is insufficient.

Universal Salt Iodization (USI): Fortifying salt with potassium iodate (minimum 15 ppm at consumer level) is the most successful intervention for IDD,.
Double Fortified Salt: Salt fortified with both Iron and Iodine to tackle two major deficiencies simultaneously,.
Biofortification: Breeding crops with higher nutrient levels (e.g., iron-rich pearl millet, carotene-rich sweet potato),.

Deworming: Periodic deworming (Albendazole) to reduce blood and nutrient loss due to helminths.
Sanitation: Improving water, sanitation, and hygiene (WASH) to prevent environmental enteric dysfunction which impairs nutrient absorption,.
Maternal Health: Improving adolescent and maternal nutrition to break the intergenerational cycle of malnutrition,.

Educating families about the importance of "protective foods" (vitamins and minerals).
Promoting "My Plate" concepts to ensure balanced consumption of food groups.
Addressing food fads and cooking practices that destroy nutrients.