An Introduction to the Science of Nutrition

Food is any material consumed to supply nutrition to an organism for the proper growth and development of that organism. In simple terms, food is the living material that sustains life. Food is generally of animal, plant or fungi origin, and has necessary nutrients, like proteins, carbohydrates, vitamins, or other minerals, which are required for the growth and maintenance of an organism. In the modern world, food is not always fresh and is consumed in varying proportions and quantities, depending on our appetite, lifestyle and interest.

Undergraduate students in nutrition study sessions are asked to record the type and amount of food they consume during a particular day, along with its frequency. They are also required to analyse their level of carbohydrate intake, and determine the amount of fibre in the diet, which can be defined as the total amount of energy used in digesting food to derive the necessary starch, and also any excess carbohydrates that must be converted into stored fat. Students are also asked to record the portion sizes, as well as the types of fats or oils consumed, and calculate the calories in the daily diet, including both the saturated and unsaturated fat.

Consumption of food is normally broken down into two categories consumables and non-consumables. Consumables refer to those edible substances that are needed to nourish an organism and grow and develop normally; whereas non-consumables refer to those that can harm organisms through toxicity, excessive chemical exposure, or an accumulation of toxins. The common components of most foods that are eaten on a daily basis include protein, carbohydrate, fat, mineral content, fibre, ash, salt, sugar, flavour, and colour. These elements vary according to food type, region, culture, and quality. Food processing techniques, and methods of preservation also contribute to differences in food quality. Today, it is also possible to eat many organic, natural and healthy food products, which were once considered exotic or specialties of restaurants.