Food micronutrients explained – The necessary essentials
Find out what micronutrients are and why we need to consume them regularly.
MSU Extension nutrition experts regularly remind people that adding more fruits, vegetables and whole grains to our daily diet promotes better health. But science often uses complex terms to describe the beneficial ingredients in food. Here is a “lowdown” on all the micronutrients in food that our body needs. Keep in mind that food also contains micronutrients that are not technically needed but which could still benefit our health.
Food contains two major groups of nutrients/molecules: Macro (large) and micro (small). Macronutrients are molecules we need in large quantities, such as carbohydrates, fats, and proteins. Water and fiber are macronutrients, too. Micronutrients are molecules we need in small quantities (but equally as important), such as vitamins and minerals.
Words to know:
- Nutrient: a dietary component that can be used by the body to stay healthy.
- Molecule: a chemical term for a structure that is larger than an atom but smaller than a cell. Nutrient molecules maintain/build human cells and tissue, power chemical reactions, and fight disease.
What are essential nutrients?
Our body creates many nutrients on its own, but those it cannot make are called “essential.” Most micronutrients are essential and can only be supplied from our food, so we need to consume these foods, and the micronutrients they contain, regularly. In contrast, most macronutrients are not essential because they can be supplied by both food and the body. In other words, you can eat a macronutrient like a carbohydrate (e.g. from foods like pasta) for energy, but when that energy source runs out, your body can convert fat into a carbohydrate to get more energy.
Micronutrients that are necessary for human health include:
Minerals – Small molecules that usually enter the body in combination with another atom and assist in a variety of bodily processes. Examples include sodium, potassium, chloride, calcium, phosphate, sulfate, magnesium and iron.
The body does not manufacture minerals, but they are found in a variety of foods - dairy, meat, nuts, fruit, vegetables. Not all foods have the same types and amounts of minerals; and too little or too much of any mineral is not healthy. The USDA has detailed information on healthy amounts of minerals and vitamins.
Vitamins – Molecules that the body cannot manufacture but needs for growth and maintenance. Two exceptions are Vitamin D, which can be produced internally from sun exposure, and Vitamin K2, which can be produced by intestinal bacteria. Both can also be obtained from food.
Vitamins are larger molecules than minerals. They are either fat-soluble (D, E, A, and K) or water-soluble (folate/folic acid, B series, and C). They have many functions in the body - Vitamin A helps grow and maintain eyes, teeth, bones, soft tissues and skin; Vitamin C is used in the immune system and is an antioxidant.
Vitamins are most prevalent in fruits, vegetables, legumes and nuts; but some are also in meats and dairy. Similar to minerals, too little or too much is not good. Vitamin C must be consumed regularly or scurvy will occur, but large doses of Vitamin C supplements can cause diarrhea, nausea, and other problems. Dietary supplements can also interfere with medications.
Omega Fatty Acids – These are the only fats that the body needs but cannot make. The two needed by humans are Omega 3 (alpha-Linolenic) and Omega 6 (Linoleic). They are used to make cell membranes and produce many hormones, and may also be capable of reducing chronic inflammation in the body and preventing disease. They are added to some foods but occur naturally in many oils, particularly fish oils.
Essential Amino Acids – These are the amino acids that the body cannot synthesize itself. The body can make some amino acids, but not all. Amino acids build protein, which has several roles in the body, including being one of the main structural units in our body. Over half of the amino acids we need, have to be regularly consumed in food. We eat muscle (meat) to get the amino acids to build our own muscle, but we can also get essential amino acids from plant-based foods such as apples, carrots, soybeans and peanuts. Certain amino acids have also shown early signs of medicinal application – arginine may help many types of health conditions from heart failure to infertility.
Fiber – This is a macronutrient because it is needed in large amounts, but it is included here because it is an essential nutrient that the body cannot make. Without it, waste is not properly eliminated from the body. It is a very long molecule that gives plants structure, and it is prevalent in fruit, vegetables, legumes, whole grains, seeds and nuts. Most of the fiber we consume is insoluble and cannot be digested; however, this type promotes healthy digestive environments and elimination of waste. We also consume smaller amounts of soluble fiber, with emerging evidence that this type may help regulate blood sugar and lower cholesterol.
All of the above are necessary for our bodies to function properly. Since they are essential, they need to be consumed daily. Eating a diverse and well-balanced diet with proper portion sizes usually provides the necessary amounts of these essential micronutrients without the addition of supplements.
For more information on healthy diets, visit Michigan State University Extension.