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Recommended Vitamin C,E & Mineral Supplements Dosages
Vitamin E and the Battle against Cancer or Cardiovascular Disease
(4/3/05)- According to a study that was led by researchers at McMaster University and Hamilton Health Sciences in Ontario, Canada people who took large dosages of Vitamin E for an average of 7 years did not see a reduction in the rate of cancer or cardiovascular diseases. The study was designed to determine whether people who took 400 IUs of vitamin E daily had a lower rate of heart related events or cancer, than those who did not take such large dosages.
Daily multivitamins contain much smaller amounts of vitamin E, ranging from 30 to 45 Ius. Patients in the study had diabetes or vascular disease and were at least 55 years old when the study began in 1993. There were slightly over 9,000 patients enrolled in the original study.
The first part of the study followed patients from January 1993 through January 1999. The results of that study were that taking large dosages of vitamin E did not decrease the risk of cancer or cardiovascular events. That original study was then extended through May 2003, and involved about 4,700 patients. The study concluded that in fact patients taking large dosages of vitamin E were 13% more likely to have heart failure and related hospitalizations than those in the placebo group.
Although the finding of slightly increased risk from taking the vitamin E the researchers concluded that this should not be taken as a definite conclusion. "Although this finding could be due to chance, several factors lead us to believe it may be real," they wrote.
(12/15/03)-Should you be taking a multivitamin pill? Many of us ask ourselves this question since we read and hear so much about how a single pill can help to improve your health. Most experts feel that healthy adults who eat a varied diet don't need vitamin supplements. Others argue that even healthy adults eating habits leave out certain important helpful nutrients.
We can not answer this question for you but we can at least explain to you what a multivitamin pill does contain so that you can help to judge for yourself if you should take one of these pills. A multivitamin should contain 100% of the FDA's recommended daily value (DV) for vitamins A (some form of beta-carotene), B1 (thiamin), B2 (riboflavin), B3 (niacin), B6, B12, C, D, E and folic acid. It should also have some vitamin K although people who are on blood thinners should try to avoid taking vitamin K.
The multivitamin pill should also contain minerals, so look for copper, magnesium and selenium. Since calcium is so bulky the multivitamin pill usually does not contain 100% of the DV for this mineral. There is no evidence that taking more than 100% of the recommended DV will make you any healthier. Taking more than the recommended dose for vitamin B and vitamin C, which are known as the "water soluble" vitamins won't harm you since your body will excrete whatever it does not need. Taking more than the recommended DV of vitamins A, D and K can cause harm because they build up in the body and can be toxic. Vitamins A, D and K are what are known as "fat soluble" vitamins.
There is an excellent site from the Institute of Medicine where you can check out the safe upper limits for all vitamins and minerals. It can be found at www.iom.edu. Click on Programs, then Food and Nutrition Board. To see more on these topics please see our articles:
The U.S. Pharmacopeia (USP) and
Medication Errors-Part I
"Seals of Approval"-Part
II
Please keep in mind that multivitamins can react with certain medications that you may be taking so check with your medical professional before taking any multivitamin. To prevent stomach upset and to improve absorption take the multi vitamin when you are having some food with it.
The U.S. Preventive Services Task Force, said it had examined several dozen studies on vitamins, and found that the results were "inadequate or conflicting." It concluded therefore that there isn't enough evidence to either recommend or reject the use of vitamin supplements as a way to reduce the risk of cancer and heart disease.
The anti-oxidant vitamins, which include vitamins A, C and E have been promoted for their benefit in preventing the heart-damaging effects of oxygen on arteries and the cell damage that might spur some kinds of cancer. Some researchers now believe that the anti-oxidant vitamins only work when they are in food rather than when taken as supplements in the form of pills.
A U.S. Government research team from the National Institute of Health has reported in the April 21, 1999 edition of the Journal of the American Medical Association that the daily recommended allowance of Vitamin C intake be increased from 60 milligrams to between 100 to 200 milligrams per day. The team headed by Dr. Mark Levine has determined that the increased dosage increases the body's ability to fight against cancer when taken in the form of fruits and vegetables.
Their evidence points to the fact that 5 servings a day of fruit and vegetables may help prevent cancer. So far they have not been able to determine if the benefit results from the Vitamin C itself or from the components of the food. They did however caution that 200 milligrams was the maximum that the body could absorb on a daily basis. The National Academy of Sciences Food and Nutrition Board is reviewing whether or not to increase the 60-milligram per day level that has been the accepted belief since 1980.
More than 20% of United States adults consume a vitamin or mineral supplement daily. A majority of supplement users (75%) consume multivitamins. One-third of supplement users (8% of US adults) specifically consumes vitamin C supplements daily. Vitamin C is the most commonly supplemented micronutrient in the US. The average vitamin C intake in the form of supplements is about 60 mg; however 6-10% of supplement users consume more than 100 mg of vitamin C daily. There is little evidence that these levels are harmful. Most of the vitamin C is extracted in urine. One study showed that while the body absorbed 70% of the vitamin C, the vast majority of that was not metabolized. Thus a 500 mg dose resulted in the body only using 110 mg. (See: Levine M, Conry-Catilena C, Wang Y, et al. Vitamin C pharmacokinetics in healthy volunteers: evidence for a recommended dietary allowance. Proc Natl Acad Sci 1996; 93:3704-3709).
Kidney Stones and Vitamin C
A majority of kidney stones (technical name: renal calculi) are composed of calcium oxalate. Development of kidney stones is related to a number of factors including lack of inhibitors of crystal formation in urine, changes in urinary pH, decreased urine volume and presence of bacteria. Risk factors to develop this condition include excessive intake of meat protein, oxalate and sodium, insufficient in take of fiber and fluids and higher ambient temperature and exposure to sunlight.
Epidemiological data do not support an association between intake of vitamin C supplements and kidney stones. (See: Curhan GC, Willet WC, and RIMM EB et al. A prospective study of the intake of vitamin C and B6 and the risk of kidney stones in men. Journal of Urology 1996; 155:1847-1851.)
Cardiovascular Death and Vitamin C
Data from the National Health & Nutrition Examination Survey (NHANES) Epidemiological Follow-up Study showed that deaths from cardiovascular disease was inversely related to regular use of vitamin C supplements in males. Conversely, in postmenopausal women (n=34,486) supplemental vitamin C (>1000 mg/day) was not significantly associated with a decrease risk of death due to cardiovascular disease. All-cause carrier deaths were inversely related to regular use of vitamin C supplements in males. (See: Enstrom JE, Kanim LE, Klein MA. Vitamin C intake and mortality among a sample of the United States population. Epidemiology 1992; 3:194-202.)
FOR AN INFORMATIVE AND PERSONAL ARTICLE ON PRACTICAL SUGGESTIONS WHEN SELECTING A NURSING HOME SEE OUR ARTICLE "Selecting a Nursing Home"
By Allan and Harold Rubin, MS, ABD, CRC, Guest Lecturer
updated April 3, 2005
To e-mail: hrubin12@nyc.rr.com or rubin@brainlink.com