9:04 PM
Admin Aldino Car Rent
Which Vitamins Do You Really Need?
And how much is too much?
HAVE YOU SHOPPED for vitamins lately? It wasn't long ago that only a few brands of multivitamins were available. Today, thousands of different vitamin and mineral supplement products are on the market, and the number is rising steadily each year. Most of us end up staring helplessly at pharmacy shelves, wondering which supplements we should be taking.
Here's a look at some of the most important vitamins and minerals --- and how to use them effectively. (If you take medications, talk to your doctor before using supplements.).
Vitamin E
Studies have suggested that vitamin E may boost the immune system, ward off cataracts and slow the progression of Alzheimer's disease. There's also some evidence that vitamin E may promote heart health by reducing the oxidation of LDL ("bad") cholesterol that can cause atherosclerosis, and also by acting as an anticoagulant. Several observational studies from Harvard University have found a roughly 40-per-cent reduction in heart-disease risk in those who took vitamin E Supplements of at least 100 international units (IU) a day for two years or more. However, based on an extensive review of current data, the US National Academy of Sciences, Food and Nutrition Board (FNB) recently concluded there isn't enough evidence to prove that taking large closes of antioxidans, such as vitamin E or C, will prevent or reduce the risk of chronic diseases.
Most people get an adequate 15 miligrams (equalling 33 IU of synthetic vitamin E) a day through diet alone, because E is found in fatty foods like vegetable oils, wheat germ, nuts and seeds. Vitamin E researcher Jeffrey Blumberg, a professor of nutrition at Tufts University in Boston, says studies, including his own, have shown that 100 to 400 IU of vitamin E a day is beneficial for optimal health.
How much is too much? At supplement doses above 1000 IU per day, vitamin E may cause an increased tendency to haemorrhage. Because it acts as an antocoagulant, those who have bleeding or clotting disorders should talk to their doctors before taking vitamin E supplements.
Vitamin C
While there's little evidence that vitamin C can prevent colds, several studies indicate that taking large doses each day at the onset of a cold probably lessens the symptoms and shortens its duration. You can get your recommended daily intake in one 250 mililitre glass of orange juice. Doses over 200 miligrams a daya result in limited intenstinal absorption.
How much is too much? Regularly taking more than 2000 miligrams of vitamin C daily can cause abdominal cramps, nause, and diarrhoea.
B Vitamins. Folic acid (the synthetic form of the B vitamin folate), B12 and B6 can protect our hearts, prevent birth defects and keep us mentally sharp as we age. All three have been linked to a possible lower incidence of heart disease, possibly because they help return to normal the blood levels of a substance called homocysteine. Elevated homocysteine levels are linked to an increased risk of heart disease and other vascular disorders.
Folic acid can also make the difference between delivering a healthy baby or one born with a birth defect such a spina bifida. Extra folic acid can now be found in enriched bread, flour, rice, pasta and breakfast cereal.
People who aren't as mentally sharp as they once were may have a vitamin B12 deficiency. Severe deficiencies cause fatigue, nerve damage and dementia, but depression and confusion can appear with milder deficiencies. Older people are particularly at risk because many are unable to absorb B12 from food (meat, fish, and chicken are the main sources). So health officials advise those over 50 who can't absorb B12 from food to get the vitamin either with a supplement or through foods fortified with it.
How much is too much? Doses over 1000 micrograms of folic acid might mask a B12 deficiency, which could cause nerve damage. As for B6, don't exceed 100 miligrams (the RDI for adults is 1.6 miligrams). Higher doses over time pose a risk of difficulties with balance, numbness, muscle weakness and nerve damage. As for B6, don't exceed 100 miligrams (the RDI for adults is 1.6 miligrams. Higher doses over time pose a risk of difficulties with balance, numbness, muscle weakness and nerve damage. Those over 50 who take folic acid should also take at least 100 micrograms of B12 a day.
Calcium
We need plenty of this mineral to maintain strong teeth and bones and reduce our risk of osteoporosis. To that end, the US FNB recently raised the RDI for calcium to 1000 miligrams for adults up to the age of 50, and 1200 miligrams for age 51 and older -- equivalent to three or four glasses of skim milk a day. Yet surveys show that the average woman gets only 600 miligrams of calcium per day.
How much is too much? More than 2500 miligrams of supplemental calcium per day may cause constipation and lead to kidney problems.
Vitamin D
Calcium won't do you much good unless you also get enough of this "sunshine vitamin," which enables the body to absorb calcium and phosphorus. Vitamin D is available in only a few foods (mainly milk, butter, egg yolks, and fortified breakfast cereal) and is otherwise produced under the skin upon exposure to the sun. How much is too much? Daily doses of 1000 to 2000 IU over time may cause nausea, headache, fatigue, heart, irregularities and elevated blood levels of calcium that can lead to severe kidney damage and other disorders.
Magnesium
This is another mineral vital for bone and dental health. The average multivitamin supplies 25 per cent of what you need, but it is also found the whole grain, nuts, legumes and dark leafy greens.
How much is too much? In supplemental doses over 350 miligrams, it cause diarrhoea and abdominal pain. They may also prevent the absorption of others minerals.
Posted in: 
0 comments:
Post a Comment