Minerals are present in our bones, blood, nerves, soft tissue, muscle, and teeth. Not only are they crucial for our skeletal structure, but they also help in all important physiological processes in the body. As an example, they help keep the fluid balance that is important to our mental and physical processes. Blood and tissue is maintained at the correct pH level through the influence of minerals, and they also let other nutrients move into the bloodstream. Minerals also act to regulate the passage of biochemicals into and out of our cells, and are used by the immune system to make antibodies.



Minerals are similar in some functions to vitamins, in that both act as catalysts, sparking cascades that are involved in the transmission of neural impulses through the nervous system, digestive processes, and muscular processes. Some of their surprising roles includes their involvement in the creation of hormones.

Minerals are also needed for some vitamins to be absorbed by our bodies. The B vitamins are an example of this - some of them need to be combined with phosphorus. And zinc allows vitamin A to be released from our livers.

Other vitamins actually help minerals to be absorbed - the pairing of vitamin C with iron, and calcium with vitamin D, are illustrations of this principle.

There are several factors that may mean we aren't getting the minerals we need, however. The first is the comparative difficulties in absorbing them. Minerals either become chemically associated with amino acids, or phytic acids, from cereal grains. Those minerals bound to amino acids during the digestive process are transported across the intestinal wall and into our bloodstream, where they can be transported to whee they need to. Minerals that become bound to phytic acids, on the other hand, are unable to cross the intestinal wall and become usable by our bodies.

Thus, many mineral supplements are chelated with an amino acid, so they can be absorbed. For minerals that we have available in food, it helps to eat some protein with a meal so that this amino acid association can occur. Even then, mineral absorption is a bit of a lottery. There is a lot of competition for the amino acid carriers, and many positively charged minerals such as calcium, sodium, magnesium, iron, zinc, sodium, copper, and others attach to the wall of our intestines when they find no other suitable carriers. This can be irritating to our gut, and these minerals are excreted when the intestinal cells they are attached to die a natural death.

Phytic acid has a particular affinity for iron, calcium, magnesium, and zinc. Other plant acids, such as oxalic acid found in sweet potatoes, spinach, and rhubarb, has an affinity for calcium and magnesium.

The nutritious food we eat is not the only problem in mineral absorption. All the things that increase urination, such as coffee and tea, alcohol, diuretic drugs and herbs, guarana and other sources of caffeine, increase the loss of minerals in our urine.

References:

1. Kirschmann and Kirschmann, The Nutrition Almanac

2. Nature And Health, October/November 2006.