Minerals – March 2003
Shall we continue last month's vitamins newsletter with a pocket guide to the minerals?
Minerals are placed into two categories; major and trace. The major minerals are required by the body in larger amounts, while the trace minerals in smaller amounts. They are essential to the body, however, despite the quantity differences.
Chief functions: maintains normal fluid & electrolyte balance, assists in nerve impulse transmission and muscle contraction
Chief functions: maintains normal fluid & electrolyte balance; part of hydrochloric acid found in stomach, necessary for proper digestion
Significant sources of both Na & Cl: salt, soy sauce/tamari, moderate amounts in milk, bread, and vege; large of amounts in processed foods (much more than necessary)!
(It's not hard to obtain the daily requirement of Na & Cl. Even a couple slices of bread a day should do it).
Chief functions: maintains normal fluid and electrolyte balance; facilitates many reactions; supports cell integrity; assists in nerve impulse transmission and muscle contraction
Significant sources: all wholefoods, all vegetables (some of better sources-spinach, broccoli, carrots, artichoke, squash/pumpkin, kumara), fruits (strawberries, banana, kiwifruit, grapefruit), avocado, legumes (some of the better-pinto, kidney, chickpeas), wheatgerm, seeds, nuts, fish, meat, kelp, milk & yogurt
Fresh foods, notably fruits & vegetables, are the best sources.
Calcium (Ca)- (major)
Chief functions: 99% is used in the bone & teeth; also involved in muscle contraction & relaxation, nerve functions, blood clotting, blood pressure and immune defenses
Significant sources: dairy products, small fish (with bones), tofu, vegetable greens (e.g. broccoli, silverbeet, spinach), cauliflower, almonds, brazil nuts, hazelnuts, sunflower & sesame seeds, tahini, legumes (esp. soy & green beans), kelp, blackstrap molasses, dried figs, miso, raisins
Phosphorus (P)- (major)
Chief functions: mineralisation of bones & teeth; part of every cell; important in genetic material, part of phospholipids, used in energy transfer and in buffer systems that maintain acid-base balance.
Significant sources: All animal tissues (meat, fish, poultry, eggs, dairy products), sunflower seeds, tofu
Magnesium (Mg)- (major)
Chief functions: mineralisation of bone; building of protein, enzyme action, normal muscle contraction, nerve impulse transmission, maintenance of teeth, and functioning of immune system
Significant sources: nuts, seeds, legumes, soy products, whole grains, dark green vege, seafood, chocolate (yippee!), cocoa, brewer's yeast, avocado, molasses, apricot, seafood, kelp, red chilli, parseley
It is not used by the body solely as a nutrient, but is a major mineral occurring in essential nutrients such as Vitamin B1 (Thiamin) and amino acids (methionine & cysteine).
Chief functions: part of proteins-stabilise their shape forming disulfide bridges; part of B vitamins biotin & thiamin (B1), and hormone insulin
Significant sources: protein sources, see thiamin & biotin sources (No deficiency is known to occur with sulfur).
Iron (Fe)- (trace)
Chief functions: part of protein hemoglobin, which carries oxygen from place to place in the body; part of protein myoglobin in muscles, which makes oxygen available for muscle contraction; necessary for the utilization of energy as part of cells' metabolic machinery
Significant sources: red meat, fish, poultry, shellfish (especially clams!), eggs, legumes (good examples: kidney beans, chickpeas), dried fruits (good examples: apricots, prunes, raisins), blackstrap molasses, artichokes, kelp, green beans, tomato juice, parsley, brewer's yeast, nettle tea, dandelion leaves, chickweed, raspberry leaf tea, kelp & seaweed products
*Absorption aided by vitamin C, acidic foods, and proteins.
Zinc (Zn)- (trace)
Chief functions: part of many enzymes; associated with hormone insulin; involved in making genetic material and proteins, immune reactions, transport of vitamin A, taste perception, wound healing, the making of sperm, and normal development of fetus
Significant sources: protein containing foods: meats, fish, seafood (especially oysters!) poultry, whole grains, vege (broccoli, spinach, peas), yogurt, suflower & pumpkin seeds, ginger, chilli powder, garlic, milk
*NZ soils are known to be LOW in Zinc.
Iodine (I)- (trace)
Chief functions: essential component of two thyroid hormones helping to regulate growth, development and metabolic rate
Significant sources: kelp, seafood, dairy products, iodized salt, *plants grown in iodine-rich soil and animals fed those plants
*NZ soils are known to be LOW in iodine.
Selenium (Se)- (trace)
Chief functions: antioxidant, regulates thyroid hormone
Significant sources: seafood, meat, whole grains, *vegetables (depending on soil content), nuts (esp. brazil nuts (2-3 per day gives the daily requirement)), brewer's yeast, molasses, garlic, onions, mushrroms, broccoli, tomatoes, radishes
*NZ soils are known to be LOW in selenium.
Copper (Cu)- (trace)
Chief functions: helps form hemoglobin, part of several enzymes
Significant sources: seafood, nuts, legumes, whole grains
Manganese (Mn)- (trace)
Chief functions: cofactor for several enzymes
Significant sources: nuts, whole grains, leafy vegetables (spinach, lettuce, silverbeet), corn, kelp, eggs, liver, seeds, legumes, alfalfa
Chief functions: helps form bones and teeth, confers decay resistance on teeth
Significant sources: tea, seafood, drinking water if fluoridated
Chromium (Cr)- (trace)
Chief functions: associated with insulin, needed for energy release from glucose
Significant sources: brewer's yeast, meat (esp. beef & liver), wheat, cheese, mushrooms, oysters, nuts, potatoes (skins), wheatgerm, green peppers, eggs, chicken, apples, prunes, bananas, spinach, molasses, spirulina
*Health hint: try increasing your chromium intake if you have frequent sweet cravings, and/or a high carbohydrate diet.
Molybdenum (Mo)- (trace)
Chief functions: Cofactor of several enzymes, including one that is responsible for the utilization of iron within the body
Significant sources: legumes, cereals, organ meats
Other trace minerals include boron (may play key role in brain activities), cobalt (key mineral in large vitamin B12 molecule), silicon (may play role in tissue development), vanadium (necessary for growth & bone development), and possibly nickel.
No known deficiencies occur amongst these minerals. The body requires them in minute amounts, making research difficult to determine if they are officially essential.
The contents of trace minerals in food largely depend upon the soils in which it is grown. This is a great reason to choose organically grown food. A major focus of organic methods is the health, quality and life of the soil; versus non-organic methods that do not so much focus upon soil health. Non-organic fertilizers tend to focus on three key elementsnitrogen, phosphorus and potassium; in comparison to organic fertilizers such as those of a seaweed
base full of multiple minerals, in addition to the three key elements mentioned. Research of this topic is only in beginning phases, but the debate seems obvious. Can't you feel the difference too?!
Whitney & Rolfes (2002) Understanding Nutrition.
Wadsworth/Thompson Learning, Belsmont.
Piko notes: Jo had a great idea to use walnut flour for the ground nuts in the January newsletter's muesli bar recipe. It's works well, is yummy (and heaps cheaper than buying whole nuts)!
Have you checked out Piko's webpage yet? Thanks to Mariska, Piko is keeping up with the times. She does a great job to update it with all the newsletters, recipes, and even some fun photos from time to time! www.pikowholefoods.co.nz