Most people can obtain all of their vitamins and minerals through diet alone; however, some require vitamin and mineral supplements (MVSs). MVMs with more than three vitamins/minerals may also help them meet their requirements.
Many foods contain essential vitamins and minerals, including whole grains, vegetables, fruits and legumes. Furthermore, some are fortified with additional calcium, iodine and magnesium for even more nutritional benefit.
Benefits
People taking multivitamin/mineral (MVM) supplements receive multiple essential nutrients in one pill, helping prevent vitamin and mineral deficiencies among certain groups.
An MVM that includes calcium, magnesium, phosphorus and vitamin D helps ensure strong bones. If these nutrients are deficient they can lead to scurvy, rickets and blindness; taking supplements with folic acid may prevent birth defects in offspring; and enough fluoride prevents tooth decay from occurring.
Minerals can be divided into two groups, macrominerals and microminerals. Macrominerals, such as potassium and calcium, are required in large amounts and support all major systems within the body, while microminerals like iron, zinc, chromium and selenium often play specific roles within our systems.
Food can often provide more vitamins and minerals than supplements do, due to other components within food that work together for our good. For instance, phytochemicals reduce risk for heart disease and some cancers.
Risks
High doses of certain minerals may cause toxicity. Iron can build up to toxic levels in the body and lead to gastrointestinal upset, nausea and black bowel actions (poo). High doses of vitamin C may cause diarrhea as well as interfere with certain medical tests – specifically blood sugar test results. Finally, calcium can bind with excess sodium and result in higher blood pressure.
As well, high intakes of certain trace minerals such as folic acid, selenium and zinc may lead to deficiencies if they are not balanced with other foods. Examples include high intakes of these three essential elements.
Randomised trials have demonstrated that multivitamin and mineral supplements do not prevent major cardiovascular disease (CVD) events in people without nutritional deficiency; however, observational studies indicate that MVM users actually experience lower rates of CVD than non-users.
Interactions
Major minerals, like potassium and magnesium, are quickly absorbed and excreted from the body unlike water-soluble vitamins; however, they may interact with some medications.
Example: Supplemental vitamin E in large doses may enhance the antiplatelet effects of aspirin, so it’s wise to separate these supplements by two hours. Also, taking both magnesium-containing antacids and iron supplements together may increase absorption of aluminum hydroxide from an antacid, thus decreasing effectiveness; accordingly it would be prudent to give each at least two hours to interact with one another before taking these substances together.
Multivitamin/multimineral (MVMM) supplements have been tested in several large, long-term randomized controlled trials conducted among older people. Most studies did not find an association between multivitamin/multimineral supplement use and CVD, cancer, eye disease, immune function or osteoporosis mortality rates and increased use of calcium supplements; however, in certain trials calcium supplementation may have increased cardiovascular events and deaths – this may be related to higher rates of coronary heart disease among postmenopausal women taking high doses rather than MVMs themselves.
Side Effects
Dietary supplements are one of the most widely consumed complementary medicines in Australia, but many don’t realize they can cause serious side effects if taken excessively. Like all medicines, an excessive intake may result in adverse side effects; furthermore they may interact with one another and interfere with certain prescription medicines.
Diet is still the best way to gain essential vitamins and minerals, however when taking mineral supplements it’s essential to monitor doses; overdosing can cause symptoms ranging from stomach ache, nausea and constipation to hair loss and easier bruising and bleeding.
Minerals, unlike vitamins, are inorganic substances derived from soil and water sources. Your body needs calcium and phosphorus in larger amounts for healthy development; others like chromium, copper, iron, zinc and selenium play less obvious yet vital roles such as helping prevent tooth decay, boost immunity or helping blood clot properly. Fluoride, iodine or selenium trace minerals also play important roles such as aiding thyroid hormone production while warding off goitre.
