Minerals are solid, inorganic, naturally occurring substances. The body has them in small amounts, but they are also available through foods. There are two types: macrominerals and microminerals.
Macrominerals are minerals needed in larger amounts. They include calcium, magnesium, phosphorus, sodium, potassium, chloride, and sulfur. Micronutrients are needed in small amounts and include trace elements iron, manganese, selenium, copper, iodine, zinc, and fluoride.
Macrominerals
Calcium
Calcium performs many essential functions in the body. As many people are aware, calcium is needed to build and maintain strong bones and slow down bone density loss. These, however, are only part of the roles that calcium has on the body. It also helps regulate muscle contraction, nerve impulse signalling, hormone signalling, and blood coagulation (clotting). Most of our calcium is in our bones and teeth, but it can also be found in the blood plasma, the body’s soft tissues, and extracellular fluid.
We lose calcium each day through skin, nails, hair, and bodily waste. If we do not have enough calcium, calcium is taken from our bones. Since our bodies cannot produce new calcium, we must get it from food. Foods high in calcium include dairy products, broccoli, green leafy vegetables (kale, bok choy, collard greens, etc), tofu, blackstrap molasses, chickpeas, beans, sesame seeds, sunflower seeds, almonds, flax seeds, and brazil nuts.
One must keep in mind that certain foods higher in calcium, such as dairy, are not necessarily better. Dairy is an acid forming food. To compensate, calcium is drawn from the bones. This means that, despite the high amount of calcium contained in milk, very little of it is retained. The ratio of calcium and magnesium (a mineral that helps in calcium absorption) in dairy products also prevent our bodies from absorbing all of the calcium. Recent studies have shown that a diet high in dairy products and animal protein has been linked with higher rates of osteoporosis, a condition in which the bones lose density and become brittle.
Oxalic acid also interferes with the absorption of calcium, as well as other minerals such as magnesium, iron, zinc, and copper. It is an odourless, organic compound that occurs in plants, animals, and humans. Some levels of oxalate can be good, but too much can have health consequences. Foods such as spinach are considered to have higher levels of oxalic acid. This can be reduced by lightly steaming it.
When eating nuts, it is recommended to soak them to remove the enzyme-inhibitors, so that the nutrients are more easily absorbable. Enzyme inhibitors are molecules that interact with enzymes and can make them inactive or slow down their reaction time. In the case of unsoaked nuts and seeds, they can interfere with the body’s absorption of nutrients. To learn more about soaking nuts and seeds, check out Soaking Nuts, Seeds, Legumes, and Grains.
It is also important to consume calcium with vitamin D and magnesium as they both help in its absorption.
Magnesium
Magnesium plays an important role in diverse biochemical reactions in the body including protein synthesis, muscle and nerve function, blood glucose control, and blood pressure regulation. It also regulates and maintains energy production, RNA and DNA, and mineral balance. We obtain magnesium primarily through foods such as beans, nuts, whole grains, and green leafy vegetables. Phytic and oxalic acid can interfere with its absorption. One of the major causes for magnesium deficiency, however, can be attributed to food processing, which removes essential nutrients from food.
Phosphorus
Phosphorus is the most abundant mineral next to calcium and is used to form strong bones; maintain pH balance; get oxygen into tissues; create energy; filter waste in the kidneys; grow, maintain, and repair tissues and cells; produce RNA and DNA; balance and use vitamins such as vitamins B and D, as well as other minerals including iodine, magnesium, and zinc; assist in muscle contraction; facilitate nerve conduction; and produce hormones. It is absorbed in the intestines and stored in the bones. It works and interacts with calcium and vitamin D.
Foods that are high in protein are generally high in phosphorus. These include meat, poultry, fish, eggs, nuts, beans, seeds, and lentils. Foods that possess lower levels of protein but still contain phosphorus include avocados, potatoes, and garlic. Unlike many other vitamins and minerals, people generally are not at risk of getting too little phosphorus, but too much. The mineral has been added to many processed foods and drinks.
Sodium
Sodium is another mineral, and an electrolyte, that is often over-consumed, due to it being added, often in the form of salt, into most everyday meals such as soups, sauces and salads, as well as into processed foods. It is important to note that salt is not the same as sodium. Salt is sodium plus chloride.
Functions of sodium in the body include working with potassium to balance fluid within cells, and maintaining pH. It is also involved in the proper function of nerve impulses and muscle contractions.
Sodium is naturally present in most foods in small amounts. Salt can also be added to many foods, but be careful of adding too much. If you choose to add salt, try to use one, such as himalayan salt, that contains more minerals, or use a salt and herb blend.
Potassium
Potassium is an electrolyte, a substance that conducts electricity in the body, and its balance in the body depends on the amount of sodium and magnesium in the blood. It plays a variety of roles, which include helping muscles contract (including the heart), regulating fluids and mineral balance in cells, and maintaining electrolyte regulation, nerve function, and normal blood pressure.
The best source of potassium is through fruits and vegetables such as oranges, avocados, bananas, tomatoes, cucumbers, zucchini, eggplant, pumpkins, potatoes, carrots, and beans.
Chloride
Most chloride comes from salt. Chloride helps balance fluid inside and outside of the body’s cells and helps maintain proper blood volume, blood pressure, and pH of body fluids. It also helps with digestion by combining with hydrogen in the stomach to make hydrochloric acid, a key digestive enzyme. Furthermore, it works with sodium and potassium in the nervous system.
While the main source of chloride tends to be from salt, it is also found in vegetables such as seaweed, olives, rye, lettuce, tomatoes, and celery. Plants that grow in or close to water such as seaweed should be consumed carefully due to contamination from radiation and other toxins. You want to be very careful to find a clean source.
Sulfur
Sulfur is contained in some of the amino acids in the body and plays an important role in protein synthesis, collagen production, and enzyme reactions.
Since it is a part of protein, it is primarily found in protein foods. These include fish, poultry, eggs, nuts and legumes. They can also be found in onions, garlic, cabbage, Brussels sprouts, kale, lettuce, seaweed, and raspberries.
Microminerals
Iron
Iron is a component of hemoglobin, which transfers oxygen from the lungs to the tissues and helps maintain healthy cells, skin, hair and nails. Excess iron is stored in the body’s tissue, but can be lost through shedding intestinal cells, sweat, and blood loss.
Our bodies only require a small amount of iron in order to meet its nutrient needs. Only a fraction of iron contained in foods is absorbed, so we have to consume several times the needed amount.
There are two forms of iron in foods: heme and nonheme. Heme iron is absorbed more easily and is found in animal food while nonheme is found in plants. Some chemicals and minerals hinder the proper absorption of nonheme iron. These include tannins in tea, calcium, polyphenols, phytates in legumes and whole grains, and some soybean proteins. Your body will also absorb iron according to its needs. If it has enough stored, then it will absorb less.
Vitamin C, though, can help significantly increase the absorption of nonheme iron. Foods high in vitamin C and iron include broccoli and bok choy. Other good sources of iron include green leafy vegetables and sea vegetables, legumes, beans, nuts, seeds, watermelon and dried fruits (no sugar added).
Animal sources of iron may be more easily absorbable, but that changes when one considers the effects that vitamin C has. Plant-based sources of iron that contain vitamin C can prove to possess more absorbable iron.
When consuming iron, it is also helpful to keep in mind that eating smaller amounts of iron throughout the day can increase absorption.
Manganese
Manganese assists in the metabolism of protein, carbohydrates, and fat. It also plays an important role in bone structure and formation; bone metabolism; formation of connective tissues; absorption of calcium and other vital vitamins and minerals; proper functioning of the thyroid gland and sex hormones; and regulation of blood sugar levels. In addition, the mineral possesses antioxidant properties and is involved in maintaining thyroid health and in monitoring the activity of free radicals.
It naturally occurs in our bodies in very small amounts and can also be found in foods such as raspberries, pineapples, garlic, grapes, beetroot, peppermint, cloves, brown rice, coconuts, almonds, hazelnuts and green vegetables.
Selenium
Selenium plays an important role in reproduction, thyroid gland function, DNA production, and protecting the body from damage caused by free radicals and infection. It is found naturally in many foods, from seafood to brazil nuts and brown rice. The selenium content in plants is dependant on the richness of the mineral in the soil. Other food sources include whole grains, kidney beans, crimini and shiitake mushrooms, asparagus, and broccoli.
Copper
Copper is central to building strong tissue, maintaining blood volume, producing energy in cells, helping in the absorption of iron, and keeping the immune system healthy. It can also act as an antioxidant and get rid of free radicals that damage cells and DNA. Excess iron and zinc can hinder its availability and absorption.
Sources of copper in food include nuts, seeds, whole grains, legumes, mushrooms, summer squash, asparagus, and leafy greens.
Iodine
The body requires iodine for the synthesis of hormones; in particular, thyroid hormones. These are necessary for regulating key metabolic functions, including blood cell production, nerve and muscle function, and body temperature. Most of the body’s stores of iodine are located in the thyroid gland.
Foods containing iodine include iodized salt (salt with iodine added); dairy products; and seafood such as fish, seaweed and kelp. Since iodine is found in most soils, plants grown in iodine-rich soils are also a good source.
Iodine content in plants and dairy can be highly variable. Overuse of a field for agriculture can strip it of its iodine, which can affect how much the plant is able to take in.
Most of the iodine in dairy is added in. Any natural iodine comes from the plants that the livestock eat. Anything that affects the iodine content of the soil and plants also influences how much the cow is able to get, and how much is in their milk. Cattle who don’t have access to fresh grass tend to have very little natural iodine, so it is added into the milk later.
Some foods contain goitrogens, which interferes with how the body uses iodine. This is not a concern for people who consume good amounts of iodine, yet many people are not getting enough.
Zinc
Zinc performs many vital roles, including growth and cell division; immunity; wound healing; breakdown of carbohydrates; and the creation of proteins and DNA.
High-protein sources generally contain high amounts of zinc. Animal products tend to be the first choice, since dietary fibre and phytic acid in plant-based foods can inhibit the absorption of zinc. Nevertheless, non-animal based sources still offer good amounts. They include pumpkin seeds, whole grains, lentils, peas, nuts, sunflower seeds, and garbanzo beans. To help promote absorption, you can soak nuts, seeds and grains; try fermented foods such as tempeh; and consume sprouted legumes and seeds.
Fluoride
Fluoride has been added to drinking water to reduce the prevalence of tooth decay. However, this can lead to excess exposure. The mineral is found naturally in soil, food, water, and other minerals. It does help reduce tooth decay and maintain bone structure, but is only needed in small amounts. Most people get enough from eating a healthy, well-balanced diet.
Chromium
The primary role of chromium is to work with insulin to regulate blood sugar levels. It also helps in fat metabolism.
Foods that contain chromium include liver, brewer’s yeast, whole grains, nuts, broccoli, apples, oatmeal, prunes, asparagus, and mushrooms.
Molybdenum
Molybdenum is found in nature in nitrogen-fixing bacteria. It acts as a catalyst for enzymes to aid in the metabolism of fats and carbohydrates. It also contributes to the use of iron in the body and helps in waste removal.
Food sources of molybdenum include beans, lentils, peas, and leafy green vegetables, though it does depend on the soil where it is grown.
Conclusion
This is not a complete list of minerals. Other trace nutrients include nickel, silicon, vanadium, and cobalt.