Nutrition science

Nutrition is the relationship of food to the well being of the human body.

Its main features are :
1) the metabolism of foods we eat.
2) the nutritive value of foods,

3) the changes in nutrient and food requirements
The 2004, WHO report shows that in India only 17% deaths are on account of infectious Diseases and over 73% were attributed to cardiovascular diseases, cancer, and respiratory diseases, diabetes and other Nutritional deficiency deaths.
Today much research has shown the positive effects of consuming a good nutritional diet to decreased risks of developing chronic, degenerative diseases or conditions.


nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment.
Nutrients are the substances that enrich the body. They build and repair tissues, give heat and energy, and regulate body processes
Organic nutrients include carbohydrates, fats, proteins (or their building blocks, amino acids), and vitamins. Inorganic chemical compounds such as dietary minerals, water, and oxygen may also be considered nutrients. A nutrient is essential to an organism as if it cannot be synthesized by the organism in sufficient quantities and must be obtained from an external source. Nutrients needed in relatively large quantities are called macronutrients (Protein, fats and carbohydrates are macronutrients which contribute in our energy production) and those needed in relatively small quantities are called micronutrients.

Proteins are made of amino acids, small units necessary for growth and tissue repair. Protein is the body's most plentiful substance except for water and, possibly, fat. Animal foods such as meat, fish, poultry, milk, and eggs are rich in protein. Good plant sources of protein are beans, peas, nuts, bread, and cereals.

Protein is a polymer of long chain of amino acids. 20% of our body weight is made of protein.
 Functions of protein:
  • Formation of Enzymes
  • Secretion of Hormones
  • Formation of antibodies
  • Block building material for cells,tissues and organs
  • Provides Energy
Starches and sugars are carbohydrates, the main source of the body's energy. Carbohydrates account for about half of the calorie intake for most Americans and up to four fifths of the calories in diets of African and Asian peoples.Occasional sweets are not harmful to a healthy, active person, but excessive sugar can lead to tooth decay when eaten between meals, especially in sticky snack foods that cling to the teeth. 
Fats and Oils
Fats and oils (which are liquid fats) are a concentrated source of energy. Fats in the diet are necessary for good health. They make certain vitamins available for use in the body, they cushion vital organs, they make up part of all body cells, and they help to maintain body temperature
Minerals are neither animal nor vegetable; they are inorganic. Almost all foods contribute to a varied intake of essential minerals. Most minerals are easy to obtain in quantities required by the body. A major exception is iron for children under age 4 and adolescent girls and women in the childbearing years. 
The discovery of vitamins began early in the 20th century. It is likely that some still are undiscovered. Eating a wide variety of foods ensures getting enough vitamins whether or not they are identified. All living things need vitamins for growth and health. The body either cannot manufacture them at all or cannot normally manufacture them in sufficient amounts, and so must absorb them from food. 
In order to live, every cell in the body must be bathed in water. Water takes an active part in many chemical reactions and is needed to carry other nutrients, to regulate body temperature, and to help eliminate wastes. Water makes up about 60 percent of an adult's body weight. Requirements for water are met in many ways. Most fruits are more than 90 percent water. 
Never Skip breakfast
1. Without breakfast, all of us -irrespective of age-are likely to experience the late morning slump: tiredness, sleepiness and the urge to sit back. Our efficiency goes down further as the day progresses.
2.Moreover, skipping the first meal of the day leads to intense hunger pangs by late morning & we end up eating chips , samosas, burgers or other high-fat unhealthy foods. Breakfast-skippers are most likely to be overweight.
3. Whole grain cereals-like Atta in paranthas & puris, Dalia, suji, etc,-are an integral part of the traditional Indian breakfast. Their high fiber and protein content provides a feeling of satisfaction, which lowers the urge to snack before lunch. On the other hand, high sugar foods actually make people sleepier, not active.
Deficiency of proteins leads to:-
  1. Hair loss
  2. Loose/Dull skin
  3. Nails won’t be proper
  4. Weakness in muscles
  5. Diseases in infants viz. marasmus(0-18 months of age) and koshiorkar(1-3 yrs of age)
  6. Poor immune system
  7. Retarded brain development in children
Elevated rate of insulin leads to:-
  • Stress on kidney
  • Liver swelling
  • Arteries hardening