Nutrients: the basics

Nutrients: the basics

People eat food, not nutrients; however, it is the combination and amounts of nutrients in consumed foods that determine health. To read one must know the letters of the alphabet; to do sums one must be able to count, add, subtract, multiply, and divide. To understand nutrition, one must know about nutrients. The study of nutrients, the ABC and numeric calculations of nutrition, will form a major part of the student’s nutrition journey, and should include:

●  the chemical and physical structure and character-istics of the nutrient

●  the food sources of the nutrient, including food composition, the way in which foods are grown, harvested, stored, processed and prepared, and the effects of these on nutrient composition and nutri-tional value

●  the digestion, absorption, circulatory transport, and cellular uptake of the nutrient, as well as regu-lation of all these processes

●  the metabolism of the nutrient, its functions, storage, and excretion

●  physiological needs (demands or requirements) for the nutrient in health and disease, and during special circumstances (pregnancy, lactation, sport events), as well as individual variability

interactions with other nutrients, nonnutrients (phytochemicals), antinutrients, and drugs

●  the consequences of underconsumption and over-consumption of nutrients

●  the therapeutic uses of the nutrient

●  factors influencing food and nutrition security and food safety.

There are more than 50 known nutrients (includ-ing amino acids and fatty acids) and many more chemicals in food thought to influence human func-tion and health. Nutrients do not exist in isolation, except for water and others in some phar-maceutical preparations. In foods, in the gut during digestion, fermentation and absorption, in the blood during transport, and in cells during metabolism, nutrients interact with each other. Therefore, a par-ticular nutrient should not be studied in isolation, but integrated with other nutrients and seen in the context of total body function. The study of nutrition also includes how to determine nutrient requirements to make recommendations for intakes and how nutri-tional status is monitored by measuring intakes, anthropometry, body composition, biochemical markers reflecting nutritional status, and the clinical signs of malnutrition.

This knowledge of nutrients and their functions will enable the nutritionist to advise individuals what and how much to eat. However, this knowledge is not sufficient to understand and address the global problem of malnutrition facing mankind today. This perception has resulted in the cultivation of social science disciplines to support knowledge from the biological sciences to address global malnutrition.