Human nutrition is the provision to obtain the materials necessary to support life. In general, people can survive for two to eight weeks without food, depending on stored body fat and muscle mass. Survival without water is usually limited to three or four days.

Nutritional science investigates the metabolic and physiological responses of the body to diet. With advances in the fields of molecular biology, biochemistry, genetics, the study of nutrition is increasingly concerned with metabolism and metabolic pathways: the sequences of biochemical steps through which substances in living things change from one form to another.

The human body contains chemical compounds, such as water, carbohydrates (sugar, starch, and fiber), amino acids (in proteins), fatty acids (in lipids), and nucleic acids (DNA and RNA). These compounds in turn consist of elements such as carbon, hydrogen, oxygen, nitrogen, phosphorus, calcium, iron, zinc, magnesium, manganese, and so on. All of these chemical compounds and elements occur in various forms and combinations (e.g. hormones, vitamins, phospholipids, hydroxyapatite), both in the human body in the plant and animal organisms that humans eat.

food group

The human body consists of elements and compounds ingested, digested, absorbed, and circulated through the bloodstream to feed the cells of the body. Except in the unborn fetus, the digestive system is the first system involved in obtaining nutrition. In a typical adult, about seven liters of digestive juices enter the digestive tract. These break chemical bonds in ingested molecules, and modulate their conformations and energy states.

NUTRIENTS

There are seven major classes of nutrients:

  1. Carbohydrates,
  2. Fats,
  3. Dietary fiber,
  4. Minerals,
  5. Proteins,
  6. Vitamins, 

These nutrient classes can be categorized as either:

  • macro-nutrients (needed in relatively large amounts) or
  • micro-nutrients (needed in smaller quantities)

The macro-nutrients are carbohydrates, fats, fiber, proteins, and water. The micro-nutrients are minerals and vitamins.

CARBOHYDRATES :OVERVIEW
CARBOHYDRATES : OVERVIEW

Carbohydrates are compounds which contain carbon, hydrogen and oxygen. They are chemically known as saccharides, as carbon, hydrogen and oxygen form saccharide groups……Read more

CARBOHYDRATE METABOLISM
CARBOHYDRATE METABOLISM

Have you ever thought how carbohydrate metabolism happens in our body? How carbs are used up by the body and where do the metabolism takes place in our body? Carbohydrates are ingested; enter into the stomach, and then into the.….Read more

IS CARBOHYDRATE – BAD OR GOOD
IS CARBOHYDRATE – BAD OR GOOD

Through the past decade, carbohydrates have got a lot of flak, apparently for making us gain weight. Carbs have always been considered as one of the reason of gaining weight…..Read more

FAT IN DIET HELPS BURN FAT FROM BODY
FAT IN DIET HELPS BURN FAT FROM BODY

I have seen people following a low-fat or fat-free diets. In recent years, fat has been thought of as an enemy number one .…..Read more

HEALTHY FATS AND IT’S BENEFITS
HEALTHY FATS AND IT’S BENEFITS

Fats have been always considered as a enemy when it comes for a weight loss or maintaining weight. Eat more fat. The fastest way to lower insulin levels is to substitute fat for processed carbohydrates……Read more