Nutrition Basics: Minerals
Along with vitamins, minerals make up the micronutrients. Within the larger group of minerals, there are three smaller categories: macrominerals, micro or trace minerals, and ultratrace elements.
Like vitamins, minerals do not provide any calories. They are also a relatively small portion of a well-rounded diet. In fact, they make up only about 4% of total body weight! Despite these facts, they are extremely important for a variety of reasons.
For example, they:
•Help give your teeth and bones their hardness,
•Alter the insides of cells to make the environment suitable for life,
•Cause fluids to flow by altering something called osmotic pressure, and
•They act as cofactors for enzymes.
The macrominerals include, calcium, phosphorus, sodium, magnesium, potassium, chloride, and sulphur.
Calcium is the most abundant in the body and accounts for nearly half of that 4%. It is partially responsible for the hardness of our bones and teeth, is important in many cellular processes (including muscle contractions), blood clotting, and enzyme activation.
Phosphorus is the second most abundant and its mass totals a little more than half that of calcium. It also helps give hardness to bones and teeth, is in our cell membranes, our DNA, makes up part of ATP (the energy molecule), and aids in pH (acid-base) regulation.
The next most abundant mineral is potassium. It’s mass totals less than a third of phosphorus. Just because the amount of mineral in the body is decreasing, does not mean that it is less important, however. Potassium is essential for maintaining water, electrolyte, and pH balance, as well as being an important part of the sodium-potassium pump. This pump is the active transport that keeps the cell in electrical balance and also lets the kidneys and intestines absorb nutrients.
In decreasing order of abundance, sulphur is next. It is a component of the sulphur containing amino acids, lipoic acid, and two of the B complex vitamins.
The next two are sodium and chloride (both the constituents of table salt). Sodium is the part of that sodium-potassium pump (usually just called the sodium pump) and is important for maintaining pH, electrolyte regulation, nerve transmission, and muscle contraction.
Chloride is the most abundant anion (negatively charged ion) in the body. It also helps maintain pH, but it is also important for enzyme activation, and is a part of gastric acid, which is necessary for proper digestion.
Magnesium is the last of the macrominerals. It is an important component of bone, aids in nerve transmission, is critical in protein synthesis, and is a key enzyme cofactor.
The microminerals exist in the body in amounts less than 1/10th of the least abundant macromineral. Though they are relatively less abundant, they are still essential at least one function in the body and health deteriorates with too little or too much of each micromineral. What follows is a list of the microminerals and a few of their most important functions.
Chromium is important for maintaining blood sugar levels and insulin sensitivity.
Copper aids in using iron stores, pigment, and neurotransmitter synthesis.
Fluoride maintains teeth and bones.
Iodine is involved with making thyroid hormone (which is an important regulator of metabolism).
Iron is the central component of hemoglobin, the molecule that carries oxygen in the blood, and myoglobulin, the molecule transports oxygen in the cells.
Manganese is important for brain and nervous system function, collagen and bones, growth and glucose and fat metabolism.
Molybdenum helps to metabolize nucleic acids among other molecules.
Selenium protects against free radicals and hydrogen peroxide.
Zinc is important for sexual maturation, the senses of taste and smell, alcohol detoxification, and protein synthesis.
The ultratrace elements are those elements that are not considered essential, but some evidence exists for a possible need. The ultratrace elements include arsenic, boron, nickel, silicon, and vanadium. Their functions are not confirmed and, if necessary, they would have daily requirements of less than 1mg/day.