Vitamin Safety
Dangerous Vitamins
By Caroline Howard
About half of us take dietary supplements, mostly vitamins and minerals, according to the American Dietetic Association. But if you're eating a healthy diet and taking vitamins, you may be getting more than you bargained for. Even if you tend to skimp on the healthy stuff, with so many fortified foods and drinks available, many medical experts are concerned that you may also be at risk for vitamin overload. Here, 10 vitamins and minerals to watch.
Vitamin A (retinol)
Recommended Dietary Allowance (RDA): 3,000 International Units (IU) for men; 2,330 IU for women. Limit: 5,000 IU
This vitamin helps maintain healthy teeth, bones, skin, vision and mucous membranes. But too much can work in the opposite direction, causing reduced bone density and osteoporosis, hair loss and liver problems. Excessive amounts of vitamin A during early pregnancy (over 10,000 IU) was linked to birth defects in a Boston University School of Medicine study. Ironically, vitamin A deficiency also causes birth defects.
Foods: Red, yellow and orange fruits and vegetables.
Vitamin B6
RDA: 1.3 mg. Limit: 100 mg
Your nervous and immune systems depend on vitamin B6, also known as pyridoxine. And if you're a big meat eater, listen up: The more protein you consume, the more B6 you need to use that protein. (Sidenote: Higher doses of B6 also benefit those who abuse alcohol). Studies suggest that excessive amounts may cause damage to the nervous system, specifically to the arms and legs. It is, however, reversible when dosage drops, according to the National Institutes of Health.
Foods: Baked potato for the vegetarians, pork loin or roast beef for the omnivores.
Vitamin B9 (folic acid)
RDA: 400 mcg. Limit: 1,000 mcg
Folate occurs naturally in food; folic acid is found in vitamins and fortified food. The specific role of both, among many benefits, is to make and maintain healthy blood. Nausea, insomnia and abdominal distension are typical symptoms of overdose. Excess folic acid can also mask signs of B12 deficiency, including anemia.
Foods: Fortified breakfast cereals, blackeye peas and spinach.
Vitamin C
RDA: 90 mg for men; 75 mg for women. Limit: 2,000 mg
Can there be too much of a good thing? According to some, including Nobel Prize winner Linus Pauling, no. His eponymous institute recommends at least 400 mg of vitamin C each day in order to best to take advantage of its antioxidant and common cold-fighting properties, among others. However much you decide to take, toxicity is very rare; the body cannot store the vitamin. However, amounts greater than 2,000 mg daily are not recommended by the National Academy of Sciences because it can can lead to indigestion, diarrhea and GI discomfort. Diabetics, pregnant women and others who are testing for blood sugar levels should also be wary of ingesting high doses.
Foods: Kiwifruit, parsley and blackcurrant all have more vitamin C than oranges
Vitamin D
RDA: 400 IU. Limit: 2,000 IU
It's claimed that as little as 10 minutes of UV-B sunlight daily offers the recommended level of vitamin D. But for many of us, including black people and those with darker skin pigments, a little dietary help is in order. Unfortunately, this vitamin best known for building strong bones and fighting rickets and osteoporosis, is naturally found in few foods. So it's really all about balancing any supplements with fortified foods and drinks. Unlike water soluble vitamins like vitamin C, that simple pass through the urine, vitamin D is fat soluble and isn't removed as easily. More than 2,000 IU daily can lead to too much calcium in the blood or hypercalcemia, which can lead to kidney stones and kidney damage.
Food: Fatty fish such as salmon and tuna, plus fortified milk and energy bars.
Vitamin E
RDA: 15 IU. Limit: 400 IU
An antioxidant, vitamin E has long enjoyed a reputation for benefits to cardiovascular health, cancer and hot flashes due to low estrogen. Recently, though, it has come under suspicion and attack as having "no proven clinical benefits," according to the Annals of Internal Medicine. Separate studies have linked excessive vitamin E intake to an increased risk of all-cause mortality, congestive heart failure and increased bleeding. The Centers for Disease Control and Prevention (CDC) has reported that over 11 percent of Americans consume in excess of 400 IU.
Food sources: Vegetables oils, including wheat germ, safflower and corn oil.
Beta-Carotene
RDA: None. Limit: None (not enough studies)
Although research is still underway, beta-carotene is thought to help boost the immune system and prevent heart disease and a number of cancers, and is especially powerful against leukemia. Consuming toxic levels of beta-carotene only occurs in very rare circumstances, but can lead to increased risk for heart disease and a temporary yellowing of the skin. Research shows that people who smoke and take high levels of beta-carotene supplements may be more susceptible to lung cancer.
Foods: Spinach and carrots for the veggie lovers; for those with a sweet tooth, go for apricots or cantaloupes.
Calcium
RDA: 1,000 mg. Limit: 2,500 mg
Calcium has one of the most important job in your body. Ninety-nine percent of our body's calcium is stored in our bones and teeth to support and maintain their structure. The remainder is found in the blood, muscles and fluid between cells. While calcium is obviously important, too much can impair kidney function and decrease absorption of other minerals in the body. Excessive intake of calcium or vitamin-D (50,000 IU or higher) overtime can result in hypercalcemia (elevated levels of calcium in the blood).
Foods: Milk, yogurt and cheese are the main suppliers, but don't overlook leafy greens.
Iron
RDA: 18 mg. Limit: 45 mg
Iron is one essential mineral that must be consumed in careful moderation. An adequate amount of iron is essential for cell growth regulation and specialization. Too much, however, can be even more dangerous than an inadequate amount. Studies show that high iron levels may be a risk factor for heart disease. Iron also competes with important minerals, like copper, for absorption in the body. The scariest possibility? Too much iron can result in iron toxicity, which can progressively damage the liver, heart and endocrine glands. Without proper care, the damage done to these organs can ultimately result in premature death.
Foods: Beans, dried fruits, eggs and fortified breads.
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Recent Comments
HOLLYWOODisLA 04:46:51 PM Jul 13 2009
This is an awful article, there are plenty of nutrients the body needs that regular foods, organic or not, cannot provide (hint vitamins and minerals), if you have any questions about any of this I would ask a professional who knows about these things in and out, someone who has lived it, I know Lee Haney, 8-time Mr Olympia, he has been involved in the vitamin, mineral, and supplement world all his life, he does phone consultations from his website leehaney.com, schedule and appointment and ask away, and all this will make sense to you all, because anyone can read a book, but how many of these doctors and nutritionist actually live it.......food for thought-LA
crazyhellboy 07:31:46 AM Jun 10 2009
The key to taking supplements is that you need the freshest and most organic supplements that your body can utilize. Your body isnât going to use fish oil bought at a drug store or warehouse store that been sitting for months. For your body to use it you need to take the most natural, organic vitamins and supplements you can get. I found them at http://www.iherb.comThe fish oil is great and I love the vitamin C and Cinnamon (for my high blood sugar, Iâm diabetic) You can also get free samples and $5 off if you use the code AMA889. I have the energy of a teenager again. Iâm 39 and feeling fine.
Larrytriv 10:17:05 AM Aug 08 2008
This article is nothing more than blatant propaganda bought and paid for by the pharmaceutical industry (in this case Merck). The author, Caroline Howard, has no background that qualifies her to me a health writer, and the so-called facts she presents are nonsense. Here is a fact that is true:There has never been one documented case of any death caused by vitamin supplements when they are taken as directed. By contrast, pharmaceutical drugs kill over 100,000 Americans each year when properly prescribed, and cause serious harm to an additional 2 million more Americans annually. The only reason these atrocious statistics are allowed to continue is because of the corrupt collusion between Big Pharma and the US Food and Drug Administration (FDA), an agency which at the administrative level has long had clear and direct ties to its pharmaceutical masters, in clear violation of its charter to protect the public's health.Don't be fooled by articles such as the one above. AOL should be ashamed
LaDawki143 10:57:03 AM Jun 28 2008
GIVE ME A FREAKIN BREAK!!!!!!!!! Do you know how much easier it would be to overdose on prescription medicines?? Do the pharmaceutical companies really think people are this stupid? I hope nobody really IS stupid enough to believe this crap. Most western culture people are deficient in vitamins and minerals from their sugar/white flour diets. You'll be hard pressed to find people who are getting TOO much nutrition. Next thing you know, they'll be trying to fool people into believing that natural herbs which have been taken for thousands of years are more dangerous than new, man-made chemical medicines because pharm companies would make more money that way. This article is ridiculous.
Dr Dave 57 09:39:59 AM Jun 28 2008
let;s see now...who sponsored THIS bit of propagandaI know, I know...the big drug companies who want us to depend on their dangerous chemicals OR could it be the FDA (who does the same thing)Oh, but WE cAN TRUST THE GOVERNMENT....they are the ones who brought us Homeland Security
Azted123 06:54:24 PM Jun 25 2008
Type your own comment hereWhat a hellava thing to print and call it AOL Health. where did you get your information? No doubt the Drug Industry whose mouth has been watering over the 9 billion dollar spent on vitamins yearly. Prescription drug have killed over 160,000 people yearly and yet you bad mouth vitamins. Show me the medical research and by whom and maybe I would believe this trashy article
Azted123 06:53:44 PM Jun 25 2008
What a hellava thing to print and call it AOL Health. where did you get your information? No doubt the Drug Industry whose mouth has been watering over the 9 billion dollar spent on vitamins yearly. Prescription drug have killed over 160,000 people yearly and yet you bad mouth vitamins. Show me the medical research and by whom and maybe I would believe this trashy article
MisterKPHETT 06:35:05 PM Jun 25 2008
This screams pharmacuetical fearmongering at its finest.
Shannanamber 06:03:52 PM Jun 25 2008
People need to learn about RDA's and the DV section on your nutrition label.RDA's were developed during World War II because soldiers would come to the hospitals needing care for wounds but they were just too sick because of a lack of nutrition. They are the minimum amount of vitamins and nutrients needed so as to not develop diseases such as Rickets and Beriberi. They figured this out by doing research by depriving prisoners of certain vitamins until they developed a disease and then slowly introduced it back into their system until the disease went away.This system also recommends that your daily caloric intake consist of 60% carbs, 30% fat, and 10% protein. That is ridiculous!Do your own research and don't believe everything the government tells you.
EHill70689 05:09:59 PM Jun 25 2008
ehill70689After reading vitamin overload and checking the RDA on just two of the many I take daily, I found that I am taking ten times the RDA of vitamin A and that's probably why my hair is falling out.
