Essential nutrients are nutrients that can't be manufactured by the body, but are required by the body in order for it to function properly. Each essential nutrient directly provides health benefits and it also works in conjunction with one or more of the other essential nutrients. The only way we can obtain essential nutrients is through the foods we consume and the natural supplements we take. There are 6 major classes of essential nutrients: vitamins, minerals, fats, protein, carbohydrates, and water.
Vitamins are organic chemical compounds that are divided into 2 categories: fat soluble vitamins, and water soluble vitamins. Fat soluble vitamins are transported around the body in fat and are stored in the liver and fatty tissues. The fat soluble vitamins are vitamins A, D, E, and K. Water soluble vitamins are transported around the body in water. The water soluble vitamins are vitamins B, C, and folic acid. Water soluble vitamins can't be stored by the body. Excess amounts of water soluble vitamins are passed through the urine. Since water soluble vitamins can't be stored by the body, they should be consumed everyday by eating healthy foods that contain them. Water soluble vitamins can be destroyed by cooking. To avoid this, it is recommended that foods containing them are eaten raw, stir-fried, steamed, or grilled. Since fat soluble vitamins are stored for long periods of time, they pose a greater risk of toxicity when consumed in excess. Eating a well balanced diet is the best way to get fat soluble vitamins. Taking supplements of fat soluble vitamins increases the risk of toxicity.
Minerals (dietary minerals) are chemical elements that provide nourishment for the body. Dietary minerals are essential nutrients and are divided into 2 basic groups: macro-minerals and trace minerals. Macro-minerals are those that are required in amounts of 100mg or more per day. Trace minerals are also required, but in smaller amounts of less than 100mg per day. The macro-minerals are calcium, magnesium, phosphorus, chloride, sulfur, sodium, and potassium. The micro-minerals (commonly referred to as trace minerals) are chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium and zinc.
Carbohydrates (also known as saccharides) are sugars and starches that provide energy for the body. The body needs carbohydrates in order to function properly. Although we get energy from protein and fats, carbohydrates are our greatest source of energy due to their supply of glucose. Glucose is the body's major source of energy. Carbohydrates are generally divided into two groups: simple carbohydrates and complex carbohydrates. Simple carbohydrates are those that are high in sugars and starches and go through the digestion process quickly. Simple carbohydrates include fruits, dairy, pasta, refined cereals, soda, processed candies, cookies, cakes, and other high sugar processed desserts. Although fruits are simple carbohydrates they're also generally high in fiber and other nutrients that allow them to digest much slower than the other simple carbohydrates. Processed sugar items like soda, candies, cookies, and other desserts go through the digestive system the fastest due to their high sugar content and their usual lack of fiber. Complex carbohydrates take the longest to digest due to their much lower sugar content, fiber, and often protein. Complex carbohydrates include vegetables, whole grains, legumes, nuts, and seeds.
One of the functions of the liver is to breakdown carbohydrates and turn them into glucose so the body can use the glucose as energy. This process takes some time, that is one of the reasons why complex carbohydrates are such a good source of lasting energy. On the other hand, refined simple carbohydrates are already mostly sugar so the liver doesn't have to do much work to digest them. They are quickly digested, causing spikes in insulin levels, crash of energy, and excess weight gain. Although fruit contain natural sugar, their fiber content allow them to pass through the digestive system much slower. While fruits are generally an excellent source of nutrients, complex carbohydrates are also an excellent source of energy. Refined, processed sugary sweets and desserts are generally empty calories because they offer very little or no nutritional value. They usually contain unhealthy fats and are low in protein and fiber.
- Glycemic Index (GI) is a measure of the effects of carbohydrates on blood sugar levels. During digestion, carbohydrates that break down quickly during digestion and release glucose rapidly into the bloodstream have a high glycemic index; and carbohydrates that break down more slowly, releasing glucose more gradually into the bloodstream, have a low glycemic index. So generally, foods with a high glycemic index will cause blood sugar levels to rise rapidly, and foods with a low glycemic index won't cause blood sugar levels to rise rapidly. The sudden spikes in blood sugar levels (also known as insulin levels) contribute to several health conditions such as type 2 diabetes, coronary heart disease, and obesity. Studies show that eating a diet that's high in simple sugars also increases the risk of developing cancer. Some vegetables, such as potatoes, have a high glycemic index. Eating legumes and low glycemic index vegetables will drastically lower the glycemic index of the meal. Also, eating the skins of potatoes along with the potatoes also lowers the glycemic index of the food. In some regions where rice is a staple for most meals, fiber rich vegetables, legumes, and protein is consumed along with the rice. In those regions there is generally a reduced risk of diabetes, obesity, and cancer.
The glycemic index of foods depends on several factors including the type of starch, physical entrapment of the starch molecules within the food, fat and protein content of the food, and organic acids or their salts in the meal. Several diets rely on the glycemic index of foods among other things. There's some criticism of the glycemic index program. One of those criticisms is that foods generally considered to be unhealthy can have a low glycemic index, while some healthy foods can have a high glycemic index. Some examples of low glycemic unhealthy foods are: chocolate cake, ice cream, some candy bars, and pure fructose. Some examples of high glycemic healthy foods are: potatoes, millet, watermelon, brown rice pasta, parsnips, and broadbeans.
Fats are lipids that play a vital role in helping the body to function properly. Fats are essential for maintaining healthy skin and hair, insulating body organs against shock, maintaining body temperature, and promoting healthy cell function. Fats also provide energy stores and are necessary for the transportation of fat-soluble nutrients throughout the body. Essential fatty acids are lipids that are required for health, but are not manufactured by the body. They can only be obtained through foods and natural supplements. The two essential fatty acids (EFAs) are Omega-3 fatty acids and Omega-6 fatty acids. Great food sources of essential fatty acids are oily fish such as salmon, mackerel, sardines, and tuna and plant foods such as olives, nuts, and seeds. Oily fish are great sources of Omega-3 fatty acids and nuts and seeds are great sources of Omega-6 fatty acids. Due to mercury levels that may be present in fish, it is recommended that fish not be eaten on a daily basis. The American Heart Association recommends eating oily fish at least two times (two servings) a week, but generally not more than 12 ounces of fish per week per person. A serving is about 3.5 ounces cooked.
For children and women who are pregnant or nursing, the U.S. Food and Drug Administration (FDA) recommends avoiding the consumption of fish that contains high levels of mercury such as shark, swordfish, king mackerel or tilefish. The FDA recommends to eat up to 12 ounces (two average meals) per week of a variety of fish and shellfish that are lower in mercury such as canned light tuna, salmon, pollock, and catfish. They also recommend to check local advisories about the safety of fish caught by family and friends in local lakes, rivers and coastal areas. Smaller fish such as sardines and herring have much lower levels of contaminants such as mercury.
There are two types of fiber: soluble fiber and insoluble fiber. Soluble fiber is dispersible in water, while insoluble fiber is not.
Soluble fiber has been associated with the decreased risk of cardiovascular disease.Soluble fiber is found in varyingquantities in all plant foods. Foods that are great sources of soluble fiber include beans, peas, lentils, apples, pears, berries, oranges, bananas, plums, prunes, and psyllium.
Insoluble fiber helps to prevent colon cancer. Insoluble fiber is found mostly on the skins and peels of plant foods. Foods that are great sources of insoluble fiber include green leafy vegetables, beans, peas, lentils, whole grain foods, nuts, and seeds.
Protein is an essential nutrient contained in every part of the body including the skin, muscles, hair, blood, body organs, eyes, fingernails, and bones. Protein is the second most plentiful substance in the body. The first being water. Protein is composed of small units called amino acids. Amino acids are the building blocks of protein. There are about 20 known amino acids, 8 of which are essential amino acids. The 8 essential amino acids are isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. There are two types of protein: complete protein (contains all 8 essential amino acids), and incomplete protein (is missing one or more of the 8 essential amino acids). Animal foods are complete protein foods that provide all 8 essential amino acids. Plant foods are incomplete protein foods that are usually missing one or more of the 8 essential amino acids. For those on plant based diets such as the vegetarian or vegan diet, eating a wide variety of plant foods can ensure sufficient consumption of all 8 essential amino acids. Animal food sources of protein include meat, eggs, milk, yogurt, and kefir. Protein is contained in all plant foods in varying amounts, but the best plant sources of protein are legumes, bean sprouts, nuts, and seeds.
The superfoods spirulina and chlorella are complete protein micro-algae. They contain all 8 essential amino acids and are also an excellent source of several other nutrients including chlorophyll, essential fatty acids, B vitamins, antioxidants, and several minerals. Spirulina is an especially rich source of potassium, and also contains calcium, chromium, copper, iron, magnesium, manganese, phosphorus, selenium, sodium, and zinc.