Nutrition is a critical part of health and development. Nutrition is the study of how food and drink affects our bodies with special regard to the essential nutrients necessary to support human health. It looks at the physiological and biochemical processes involved in nourishment and how substances in food provide energy or are converted into body tissues.
These nutrients, which are the source of energy for our bodies, are classed as: carbohydrates, fats, fibre, minerals, proteins, vitamins and water. Good nutrition means obtaining the right amount of nutrients from healthy foods in the right combinations. An important part of the study of nutrition is looking at diseases that can result from malnutrition and the role that food plays in the development of chronic disease.
Poor nutrition can lead to a lack of energy, digestive problems, food allergies, weight gain, depression and anxiety as well as many of today’s most prevalent chronic diseases like coronary heart disease, cancer and ADHA. Having nutritional knowledge and making informed choices about the foods you eat can help you achieve optimum health over your lifetime.
There are seven main classes of nutrients that the body needs. These are carbohydrates, proteins, fats, vitamins, minerals, fibre and water. It is important that everyone consumes these seven nutrients on a daily basis to help them build their bodies and maintain their health. Deficiencies, excesses and imbalances in diet can produce negative impacts on health, which may lead to diseases.
Carbohydrates are referred to as energy-giving foods. They provide energy in the form of calories that the body needs to be able to work, and to support other functions.
Proteins are needed in our diets for growth (especially important for children, teens and pregnant women) and to improve immune functions. They also play an important role in making essential hormones and enzymes, in tissue repair, preserving lean muscle mass, and supplying energy in times when carbohydrates are not available.
Fats and oils are concentrated sources of energy and so are important nutrients for young children who need a lot of energy-rich food. Fats can also make meals more tasty and satisfying. Fat is found in meat, chicken, milk products, butters, creams, avocado, cooking oils and fats, cheese, fish and ground nuts.
Fibre is a mixture of different carbohydrates which are not digested like other nutrients but pass through the gut nearly unchanged.
Based on the amount of the nutrients that each person needs to consume on a daily basis, these nutrients are categorised into two groups. These are macronutrients, which should be consumed in fairly large amounts, and micronutrients, which are only required in small amounts.
‘Macro’ means large; as their name suggests these are nutrients which people need to eat regularly and in a fairly large amount. They include carbohydrates, fats, proteins, fibre and water. These substances are needed for the supply of energy and growth, for metabolism and other body functions
Macronutrients provide a lot of calories but the amount of calories provided varies, depending on the food source. For example, each gram of carbohydrate or protein provides four calories, while fat provides nine calories for each gram.
Micronutrients - As their name indicates (‘micro’ means small) micronutrients are substances which people need in their diet in only small amounts. These include minerals and vitamins.
Although most foods are mixtures of nutrients, many of them contain a lot of one nutrient and a little of the other nutrients. Foods are often grouped according to the nutrient that they contain in abundance.