Good nutrition is the cornerstone for survival, health and development, while poor nutrition (malnutrition) presents significant threats to human health. A malnourished person is susceptible to infections and different diseases and this is because the body lacks the ability to fight and resist these infections due to the absence of the necessary nutrients.

Malnutrition, as it is generally believed, is the result of a deficiency of one or more nutrients — under-nutrition and also, it is an excessive intake of nutrients — over-nutrition.

Malnutrition is a broad term commonly used as an alternative to under-nutrition, but technically, it also refers to over-nutrition — to the current epidemic of obesity and related diseases such as diabetes in both the industrialised and developing world.

Over-nutrition
Over-nutrition is a condition of excess nutrient and energy intake overtime i.e. a condition where there are more nutrients than required for normal growth. In over-nutrition, nutrients are over supplied to the body, relative to the amounts required for normal growth and development, and metabolism. It results from eating too much food and also eating too many of the wrong things, not exercising enough or taking too many vitamins or other dietary replacement. Over-nutrition is associated also with eating too much food and hence, having an excessive intake of many nutrients rather than of a single one. It also often results from the use of self-prescribed over-the-counter (OTC) vitamins and mineral supplements.

The term over-nutrition, in a nutshell, can refer to:
•Obesity: brought on by general overeating of foods high in calorie content.
•Over-supply of a specific nutrient or categories of nutrients such as mineral or vitamin poisoning due to excessive intake of dietary supplements or foods high in nutrients (such as liver) or nutritional imbalances caused by various fad diets (diets which become fashionable but are not necessarily nutrients).
Risk of over-nutrition is also increased by being more than 20 per cent overweight, consuming a diet high in fat and salt and also taking high doses of:
•Nicotinic acid (niacin) to lower elevated cholesterol levels.
•Vitamin B6 to relieve premenstrual syndrome
Vitamin A to clear up skin problems
•Iron or other trace minerals not prescribed by a doctor.

Also, when ingested in very high doses, once or habitually, preformed vitamin A can cause headache, vomiting, bone abnormalities and liver damage, vitamin D toxicity can lead to the deposit of calcium in soft tissues and irreversible kidney and cardiovascular damage.

Under-nutrition
Under-nutrition is a type of malnutrition caused by inadequate food intake or the body’s inability to make use of needed nutrients. Under-nutrition is usually thought of as a deficiency of one or more nutrients, primarily calories (that is overall food consumption) or of protein.

Under-nutrition is a consequence of consuming too few essential nutrients or using or excreting them more rapidly than they can be replaced.

People exposed to such prolonged stressors may be undernourished, even if they consume an appropriately normal diet. Prolonged physical stress causes the body to break down internal protein stores, and protein is excreted as a result.

Infants, young children and teenagers need additional nutrients, so do women who are pregnant or breast-feeding. Nutrient loss can be accelerated by diarrhea, excessive sweating, hemorrhage, or kidney failure. Nutrient intake can be restricted by age-related illness and condition, excessive dieting, severe injury, serious illness, a lengthy hospitalisation or substance abuse.

Although under-nutrition is not widespread as such in urban places, it does exist as a result of poverty, illness, neglect, poor dietary planning, or environmental hazards. In developed countries, under-nutrition is usually far less common than over-nutrition. However, under-nutrition does occur, especially in people who are very poor, such as the homeless, those who have psychiatric disorder and also, people who are very ill may be unable to eat enough because they have lost their appetite or because their body’s need for nutrients is greatly increased.

Poverty and lack of food are the primary causes of under-nutrition. There is an increased risk of under-nutrition associated with chronic diseases, especially disease of the intestinal tract, kidney and liver. Patients with chronic diseases like Cancer, AIDS and intestinal disorders may lose weight rapidly and become susceptible to undernourishment because they cannot absorb valuable vitamins, calories and iron.

People with drug or alcohol dependencies are also at increased risk of under-nutrition. These people tend to maintain inadequate diets for long periods of time and their ability to absorb nutrients is impaired by the alcohol or drugs effect on body tissues, particularly the liver, pancreas and brain.

When 4.5kg or more is lost unintentionally, it may be a sign of under-nutrition. People who are undernourished may be skinny or bloated. Their skin is pale, thick, dry and bruises easily. Rashes and changes in pigmentation are common. Hair is thin, tightly curled and pulls out easily. Joints ache and bones are soft and tender. The gums bleed. The tongue may be swollen or shriveled and cracked. Visual disturbances include night blindness and increased sensitivity to light and glare.

Other symptoms of under-nutrition include anemia, diarrhea, disorientation, goitre (enlarged thyroid gland), loss of reflexes and lack of co-ordination, muscle twitches, scaling and cracking of the lips and mouth.

Other symptoms of under-nutrition include:
. Anemia
. Diarrhea
. Disorientation
. Goitre (enlarged thyroid gland)
. Loss of reflexes and lack of co-ordination
. Muscle twitches
. Scaling and cracking of the lips and mouth

Undernourished children may be short for their age, thin, and have weakened immune systems.

The treatment of malnutrition is based on nonnalizing nutritional status which starts with a nutritional assessment. This process should be carried out by a clinical nutritionist or registered dietitian (RD) as it enables the nutritionist or Dietician to confirm the presence of malnutrition, assess the effects of the disorder, and fonnulate diets that will restore adequate nutrition.