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Brain protection

“You never hear about the positives of cigarette smoking,” a friend of mine used to say. “For instance, when you smoke, non-smokers leave the room. I like that!”

He was joking, of course. But he was right about one thing: You don’t hear much about the fact that smoking – or, more specifically, nicotine – appears to offer protection from Parkinson’s disease (PD), multiple sclerosis and other central nervous system disorders.

This health paradox came into play with the results of a recent study in which researchers in the Netherlands investigated a possible relationship between high homocysteine and Parkinson’s disease.

Block that amino acid!

Researchers at the Erasmus Medical Center in Rotterdam began with this hypothesis: Elevated levels of the amino acid homocysteine may contribute to the death of neurotransmitter cells associated with Parkinson’s disease. In that case, folate and vitamins B6 and B12 (which metabolize homocysteine) may help reduce PD risk.


  • Researchers accessed data from a large, population-based study in which dietary and medical records were collected from volunteers over the age of 55
  • Researchers evaluated dietary intake of folate and vitamins B6 and B12 for more than 5,000 subjects who showed no signs of PD or dementia at the outset of the study
  • PD was assessed with frequent in-person monitoring and regular monitoring of medical records for nearly 10 years
  • 72 subjects developed PD during the study period

Initial results showed that subjects with the highest intake of vitamin B6 had a significantly lower risk of PD when compared to subjects with the lowest intake of the vitamin. But folate and B12 intake didn’t affect PD risk.

Further analysis revealed that the apparent B6 protection was mostly restricted to cigarette smokers. The Erasmus team concluded that the antioxidant activity of the vitamin might protect brain cells from free radicals created by smoking.

411 on B6

“All in all, B6 is an amazing nutrient.”

That was the reaction from HSI Panelist Allan Spreen, M.D., when I asked him about B6 last year in regard to a study that showed how B6 intake might help prevent colorectal cancer. Other studies have shown that B6 plays a role in the development of brain neurotransmitters, helps prevent heart disease, and can relieve symptoms of morning sickness and carpal tunnel syndrome.

Dr. Spreen told me that in his own practice he’s recommended the vitamin as a diuretic, “Especially in women, and most especially if there’s fluid retention associated with their monthly cycle.”

As for dosage, Dr. Spreen recommends 100 to 400 mg per day. “Rarely, if ever, do I go above that. There have been reports of B-6 ‘toxicity,’ which consists of numbness and tingling in the hands and fingers (which is also what a deficiency can do, oddly enough), but it’s hard to do. I did a literature search years ago and came up with only six cases. This ‘toxicity’ requires in the neighborhood of 2,000 mg daily for at least a monthdoses as low as 1,000 mg can do it, but they require longer periods of time.

“B-6 is definitely more effective in the company of magnesium – they work together intimately in the body. 100 mg or so of B-6 with 500 mg of magnesium is a good starting point (and ending for many).”

Talk to your doctor before adding B6 to your supplement regimen. Meanwhile, bananas and chicken breast contain ample amounts of vitamin B6, which can also be found in red meat, fish, beans, fruits and vegetables.

“Dietary Folate, Vitamin B12, and Vitamin B6 and the Risk of Parkinson Disease” Neurology, Vol. 67, No. 2, 7/25/06,