Macronutrients, micronutrients and phytochemicals

Hello and welcome back. In the last lecture we discussed the meaning of prebiotics and probiotics. In this lecture we will conclude our introduction by explaining what is meant by micronutrients and which micronutrients are essential for our health, what are antioxidants and other bioactive compounds often found in superfoods. Later in this course you will discover how to check the nutrient content of the food you are eating and your own nutritional needs. Where regulations permit it, the content in micronutrients of certain foods is used to back up health claims on the labeling, so it could be worthwhile to talk about their meaning before embarking further in our journey.

The nutrients substances contained in two foods are broadly classified into two categories macronutrients and micronutrients. Macronutrients are the compounds that are consumed by humans in the largest quantities and that provide the majority

of energy: they are carbohydrates such as sugar and starches, proteins and fats. Proteins are formed by chains of amino acids while in humans fats are formed by molecules of a fatty acid linked to a glycerol molecule. As we will see shortly there are some amino acids and fatty acids that humans cannot synthesize and we must obtain them through our diet. water is obviously a macronutrient - as we have to consume large quantities of it every day. All other molecules or chemical elements that we ingest are considered to be micronutrients even if we need a relatively large quantity of some of

them: calcium, sodium, potassium and a few more. we couldn’t live without enough water or without ingesting enough calories but the term essential nutrient is reserved for those substances that cannot be synthesized by our bodies but are needed for some vital process. They include two essential fatty acids nine essential amino acids 13 vitamins and 15 minerals. serious deficiencies of the essential nutrients are linked with both physical and psychological symptoms and in extreme cases can lead to death. This is why high levels of essential nutrients are often listed among the qualities of superfoods, and in some cases a single serving of a food could represent the entire daily requirement of multiple essential micronutrients.

Our food contains also a wide array of molecules that aren’t essential nutrients, nor macronutrients. As most super foods are fruits, vegetables or leaves these molecules often fall under the umbrella of phytochemicals or chemical compounds produced by plants with a specific goal. Amongst these molecules we can find antioxidants. Virtually all living beings developed mechanisms to keep oxidation in check and a significant amount of healthy molecules contained by super foods has antioxidants characteristics. However the picture is more complex than that as the antioxidant properties of these molecules might not be the reason why they could improve our health. Lastly, anti-inflammatory molecules such as omega-3 fatty acids are often found in superfoods.

Inflammation is a complex response to harmful stimuli and it cannot be summarized in a few sentences but chronic inflammatory states have been linked with age-related diseases and to the phenomenon known as inflammaging and there is the possibility, not yet completely investigated that foods containing them might help us obtain a healthy and active aging. That was it for this lecture thank you for following us and see you soon. Bye!