Nutrition is defined by the World Health Organization as the intake of food in relationship with the diet each body needs. It is the practice of consuming and utilizing foods that the organisms and cells required to stay alive.
A good nutrition is a balanced and completed diet in addition to a constant physical activity, this leads to a constant good health. On the contrary, poor nutrition can lead to diseases, lack of productivity, and the reducing of mental and physical development and immunity.
There is a huge difference between dietetics and nutrition:
- Dietetics is the understanding and the exchange of information of nutrition for people to make informed choices about food and their lives.
- Nutrition is the study of the nutrients that the food has and how the body uses them, and the relationship between diet, health and disease.
Nutrients are divided in two major categories, macronutrients are the ones that the body need in large quantities and are measured in kilocalories(kcal) and micronutrients are the opposite, the body needs them is a smaller amount.
Macronutrients give energy to the body most of the time and are classified in the following:
- Carbohydrates: molecules made of hydrogen, carbon and oxygen atoms that contain glucose and starch and take a long time to break down that don´t make blood sugar levels raise. There are 4kcal of carbohydrates per gram.
- Proteins: made of hydrogen, carbon, oxygen and nitrogen molecules that repair tissue as one of its major functions. There are 4kcal of proteins per gram.
- Fats: are made of three molecules of fatty acid (hydrogen, carbon and oxygen) combined with a molecule of alcohol glycerol. 9 kcal of fats per gram.
The ones that doesn´t give energy are:
- Fiber: consists mostly of carbohydrates but has a limited absorption by the body so the sugars and starches don´t reach the blood stream.
- Water: about 70% of our body that is not fat mass is water. The amount of water per day depends on the conditions of the person and the environment each one lives in. Normally, scientist and doctors recommended 2 liters of water per day.
Micronutrients are divided into the following:
- Minerals: are the other chemical elements that our body needs apart from carbon, hydrogen, oxygen and nitrogen. Some examples are Potassium, Sodium, Calcium, Zinc, between others.
- Vitamins: organic compounds that our body needs in small amounts. They are classified for what they do and not by their structure. The divisions are 4 fat-soluble (A, D, E, and K) and 9 water-soluble (8B vitamins and vitamin C). Water-soluble vitamins tend to be eliminated faster, so the body needs more.
World Health Organization. (2016). Nutrition. Retrieved September 11, 2016 from http://www.who.int/topics/nutrition/en/