Nov
01
2004

Not All Vitamins Prevent Cancer

By | Cancer, Nutrition, Prevention, Vitamins and supplements

Even in the recent past, vitamins were looked at as an essential weapon to prevent illness, however, a large study by the Cochrane Hepato-Biliary Group at the Centre for Clinical Intervention Research at Copenhagen University has come up with disappointing evidence.

A large evidence-based analysis was performed involving a population of 170,525 persons who were enrolled in randomized trials. They received a regimen of antioxidant supplementation that included beta-carotene, vitamin A, vitamin C, and vitamin E daily or on alternate days for 1 to 12 years, along with selenium every year for 2 to 4 years.
All trials reported the separate or combined incidence of cancer of the esophagus, colon, pancreas, stomach or the liver.
Results showed that beta-carotene alone, the most widely tested antioxidant for cancer prevention, did not have substantial cancer-fighting properties in gastrointestinal cancers. The devastating blow is the fact that beta-carotene in combination with vitamin A and vitamin C significantly increased mortality! Recent studies examining vitamin C show, that it can be an antioxidant, but it also can be a pro-oxidant (the less desirable quality). Trials involving selenium very clearly showed that it might have beneficial effects on the incidence of gastrointestinal cancers.
Following these news it would be a grave mistake to assume, that fruit and vegetables with their built-in antioxidants, micronutrients, dietary fiber and beneficial plant-chemicals have fallen off grace.

Not All Vitamins Prevent Cancer

Not All Vitamins Prevent Cancer

The truth is, that fruit and vegetables typically contain safe levels of vitamins. Most studies have reported that adequate intake of fruit and vegetables are indeed associated with a low incidence of cancer.
The study, however, clearly points out the pitfalls of vitamin supplementation.
-“The more the better” does not apply when it comes to taking vitamins.
-Antioxidants according to this study are not as beneficial for cancer prevention as was thought of in the past.
– Only vitamin C and selenium held up to the scrutiny of the evidence-based researchers with regard to having preventative effects regarding the above named gastrointestinal cancers.

Reference: The Lancet, Vol. 364, Number 9441, pg.1219-28,  October 2, 2004

Last edited December 7, 2012

Mar
01
2004

Vitamins C And E – A Weapon Against Alzheimers

By | Alzheimer’s disease, Nutrition, Vitamins and supplements

A study in a recent edition of the Archives of Neurology reports about 4740 patients from Cache County, Utah, who were 65 years or older and were followed over 5 years. At the start it was found that those who had taken vitamin C and E on a regular basis as separate supplements had a 78% lesser risk of developing Alzheimers (correct medical term: “Alzheimer’s disease”).

5 years later out of 3227 survivors who were at risk 104 more people had developed Alzheimers, but 64% of those who combined vitamin C and E as a supplement did not develop Alzheimers. Dr. Peter Zandi from the Department of Mental Health, Bloomberg School of Public Health, The Johns Hopkins University/ Baltimore, Md was the lead author of this study. He stated that this was only an observational study, but that the data was convincing enough to warrant a full-scale controlled trial to examine the value of anti-oxidant agents (such as vitamin C and E) as a preventative against Alzheimers. There were a number of built-in controls such as vitamin C alone, vitamin E alone and multiple vitamins (including vitamin C and E in smaller dosages) that were all ineffective in preventing Alzheimers. The daily dosages that were necessary for the protective effect were vitamin C 500mg to 1000 mg or more per day as well as 400 IU to 1000 IU of vitamin E per day. The U.S. recommended daily allowance was insufficient for the protective effect. These dosages typically are in the order of 22 IU of vit. E and 75 to 90 mg of vit. C. Vitamin B complex alone was also ineffective in protecting against Alzheimers.

Vitamins C And E - A Weapon Against Alzheimers

Vitamins C And E – A Weapon Against Alzheimers

Comments: There are many unanswered questions about Alzheimers, but this paper gives valuable hints in terms of the protective effect of two vitamins (vitamin C and E taken as separate supplements daily). There are other factors such as genetic ones and perhaps a dysregulation of the cholesterol brain metabolism that lead to the production of a glue-like substance, called “beta-amyloid” ,that causes memory loss in Alzheimers patients. Testosterone has recently also been noticed to be important in the prevention of Alzheimers disease. In addition to these vitamin supplements a low glycemic, low fat diet would likely be very beneficial together with a regular exercise program and calorie restriction to prevent Alzheimers disease in many patients (prevention of the metabolic disease).

More info on Alzheimer’s disease: http://nethealthbook.com/neurology-neurological-disease/alzheimers-dementia-and-delirium/

Arch Neurol – 01-JAN-2004; 61(1): 82-8

Last edited October 26, 2014