Starvation

Overview :

Adequate nutrition has two components, necessary nutrients and energy in the form of calories. It is possible to ingest enough energy without a well-balanced selection of individual nutrients and produce diseases that are noticeably different from those resulting from an overall insufficiency of nutrients and energy. Although all foods are a source of energy for the human body, it is possible to consume a seemingly adequate amount of food without getting the required minimum of energy (calories). For example, marasmus is the result of a diet that is deficient mainly in energy. Children who get enough calories, but not enough protein have kwashiorkor. This is typical in cultures with a limited variety of foods that eat mostly a single staple carbohydrate like maize or rice. These conditions overlap and are associated with multiple vitamin and mineral deficits, most of which have specific names and set of problems associated with them.

• Marasmus produces a very skinny child with stunted growth.
• Children with kwashiorkor have body fat, an enlarged liver, and edema—swelling from excess water in the tissues. They also have growth retardation.
• Niacin deficiency produces pellagra characterized by diarrhea, skin rashes, brain dysfunction, tongue, mouth and vaginal irritation, and trouble swallowing.
• Thiamine (Vitamin B₁) deficiency causes beriberi, which can appear as heart failure and edema, a brain and nerve disease, or both.
• Riboflavin deficiency causes a sore mouth and throat, a skin rash, and anemia.
• Lack of vitamin C (ascorbic acid)—scurvy—causes hair damage, bleeding under the skin, in muscles and joints, gum disease, poor wound healing, and in severe cases convulsions, fever, loss of blood pressure, and death.
• Vitamin B₁₂ is needed to keep the nervous system working properly. It and pyridoxine (vitamin B₆) are both necessary for blood formation.
• Vitamin A deficiency causes at first loss of night vision and eventually blindness from destruction of the cornea, a disease called keratomalacia.

• Vitamin K is necessary for blood clotting.
• Vitamin D regulates calcium balance. Without it, children get rickets and adults get osteomalacia.
  
  

  Next