Nutritional Diseases: Causes, Effects and Prevention

Nutritional diseases arise from inadequate intake of essential nutrients, impacting the body’s ability to function properly. These deficiencies can be caused by environmental factors, such as food scarcity, or health conditions like anorexia and chronic diseases. Both macronutrient and micronutrient deficiencies pose significant health risks. Addressing these deficiencies through proper nutrition and supplementation is crucial for preventing associated diseases and ensuring overall well-being.

Understanding Nutritional Diseases

1. Nutritional Inadequacy and Deficiency

• • Nutritional Inadequacy: It involves an intake of nutrients that is lower than the estimated average requirement, whereas ‘nutritional deficiency’ consists of severely reduced levels of one or more nutrients, making the body unable to normally perform its functions and thus leading to an increased risk of several diseases. 
  • Causes of Malnutrition: Malnutrition could be caused by environmental factors, like food scarcity, as well as disease conditions, like anorexia nervosa, fasting, swallowing inability, persistent vomiting, impaired digestion, intestinal malabsorption, or other chronic diseases. 
  • Macronutrient Deficiencies: could cause kwashiorkor, marasmus, ketosis, growth retardation, wound healing, and increased infection susceptibility.
  • Micronutrient Deficiencies: lead to intellectual impairment, poor growth, perinatal complications, and degenerative diseases.

• Example: iron, folate, zinc, iodine, and vitamin A etc.

• Preventing macro- and micronutrient deficiency is crucial, and this could be achieved through supplementation and food-based approaches.

2. Micronutrient Deficiency

• Protein-Energy Malnutrition (PEM): It is a condition in which individuals have very little dietary intake of proteins, energy or both; it is thus prevalent in developing countries because of insufficient dietary intake. The two major diseases linked with this condition:
  • Marasmus: It is complete food deprivation with exceptionally limited quantities of protein and energy. 
    • Infants with marasmus are exceptionally underweight (as they have lost almost all their subcutaneous fat) and their body appears to be a combination of only bones and skin.

• • Kwashiorkor: It is characterised by extreme protein deficiency and appears in children that, after being weaned from breast milk (containing high protein), are fed carbohydrate-rich diet sources without sufficient protein intake. 
    • The main characteristic of kwashiorkor is swollen belly caused by fluid retention (edema). 
    • Kwashiorkor suppresses the production of insulin, causing a reduced protein synthesis which leads to hypoproteinemia, immunosuppression, and diarrhoea. 

Anthropometric Indicators for Child Malnutrition:

• Stunting: is low ‘height for age’.
• Wasting: is less ‘weight for height’.
• Underweight: is less ‘weight for age’. 

Ketosis: Long-term insufficiency of carbohydrate intake leads to ketosis (increased ketone production), which is characterised by the peculiar sweet odour of the patient’s breath.

Essential Fatty Acid Deficiency: Omega-3 and Omega-6 are polyunsaturated and essential fatty acids (EFA). 

• Clinical symptoms of EFA deficiency include diminished growth in children and infants, scaly dry rash, reduced wound healing, and increased infection susceptibility. 
• A lower omega-3 index is associated with a higher risk of mortality by coronary heart disease. 
• Replacing other dietary saturated fatty acids (SFAs) with Omega-6, PUFA decreases the total blood cholesterol.

3. Micronutrient Deficiency

• Impact of Insufficient Micronutrient Intake: A lower micronutrient consumption than the Recommended Dietary Allowance might lead to chronic metabolic disorders.
  • In industrialised and developing countries, micronutrient deficiencies affect more than 2 billion people of all ages (especially pregnant women and children below 5 years of age) and are linked with almost 10% of child deaths. 
• Common Micronutrient Deficiencies: Iron, folate, zinc, iodine, and vitamin A are among the most occurring micronutrient deficiencies in the world.
• Vitamin A (Retinol): Symptoms of vitamin A deficiency include xerophthalmia, Bitot spots development, and night blindness. 
  • With the progression, keratomalacia and permanent blindness may take place.
• Vitamin B1 (Thiamine): Deficiency of this vitamin causes Beriberi which is of two types:
  • Wet Beriberi: affects the cardiovascular system.
  • Dry Beriberi: can damage the central nervous system (CNS) and disrupt motor functioning (the movement of the muscles). It can also cause impaired reflexes and numbness in the extremities. 
• Vitamin B3 (Niacin): Its deficiency results in a condition known as pellagra (triad of dermatitis, dementia, and diarrhoea)
• Vitamin B6 (Pyridoxine): It causes anaemia, peripheral neuropathy, seborrheic dermatitis, glossitis, cheilosis, depression, celiac disease, Crohn’s disease, and seizures.
• Vitamin B12 (Cobalamin): Its deficiency can lead to megaloblastic anaemia, fatigue, weakness etc.
• Vitamin B9 (Folic acid, Folate): Untreated folic acid deficiency can lead to megaloblastic anaemia, pancytopenia, glossitis, angular stomatitis, and oral ulcers.
• Vitamin C (Ascorbic acid) [UPSC 2014]: is considered an essential nutrient (derived from the diet); its deficiency causes scurvy (gum disease) and could also lead to behavioural and mood changes.
• Vitamin D (Calciferol) [UPSC 2014]:  Its deficiency causes hypocalcemia and hypophosphatemia, which lead to osteomalacia among adults and rickets among children.
• Vitamin E (Alpha-tocopherol) [UPSC 2014]: The major characteristics of vitamin E deficiency (which is rare) include ataxia, myopathy, and pigmented retinopathy, like retinitis pigmentosa with vision loss. 
• Vitamin K (Phylloquinone, Menaquinone): Its deficiency leads to coagulation disorder. In newborns, vitamin K deficiency is called ‘hemorrhagic disease of the newborn’.
• Calcium:  A long-standing calcium deficiency can lead to cataracts, dental changes, brain alterations, osteoporosis, and rickets. 
• Iron: Iron is a major contributor to haemoglobin synthesis, depletion of its reserves leads to microcytic hypochromic anaemia, characterised by smaller red blood cells containing a lesser haemoglobin.
• Iodine: Iodine is a trace element that plays a major role in thyroid hormone synthesis, and its deficiency can cause Goiter (Goitre).
• Zinc: Zinc deficiency symptoms can include skin lesions, increased susceptibility to infection, diarrhoea, poor appetite, night blindness, reduced taste and smell acuity, hair loss, low sperm count, impotence, and slow wound healing.
• Magnesium: Its deficiency is linked with colorectal cancer, osteoporosis, hypertension, metabolic syndrome, and diabetes. 
• Selenium: Its deficiency can lead to Keshan disease (cardiomyopathy) and Kashin-Bek disease (deforming arthritis) and has a negative impact on spermatogenesis, immunocompetency, thyroid function, cardiovascular diseases, and mood swings.
• Fluoride: Its deficiency can lead to dental caries and bone problems.
• Biotin: Its deficiency leads to metabolic acidosis, conjunctivitis, ataxia, organic aciduria, developmental delay, encephalopathy, sensorineural hearing loss, seizures, periorificial dermatitis, and alopecia.

Conclusion

• Preventing nutritional deficiencies is essential for overall health and development. Ensuring adequate intake of both macronutrients and micronutrients can prevent severe health conditions and improve quality of life. 
• Education, proper dietary practices, and supplementation where necessary can combat malnutrition. 
• By prioritizing nutrition, we can reduce the prevalence of nutritional diseases and promote a healthier population.