Friday, December 27, 2013

One a Day Keeps Nothing Away

Vitamin use is ubiquitous in Canada.  50% of women and 35% of men take a daily vitamin or mineral supplement.  They are so commonly used that few question their necessity.

James Lind was an 18th century Scottish physician tasked with finding a cure for scurvy, a greater threat to the Royal Navy than enemy arms.  Instead of relying on anecdotes as his colleagues did, he conducted the first known clinical trial.  Citrus fruit was so obviously effective that supply of lemon juice was made mandatory on all British ships.

It took 100 years to discover that vitamin C in citrus fruits is what cures scurvy, but Lind’s rational approach nonetheless identified the best treatment and saved lives.  

Contrast this with the approach taken by Linus Pauling and his countless followers.

Pauling was an American scientist who won the Nobel Prize in Chemistry and the Nobel Peace Prize.  Then he met Irwin Stone.

Stone convinced Pauling, just by saying so, that if he took 3000 mg of vitamin C daily, he would live a long life.  Pauling was so excited about vitamin C he increased his daily dose to 200 times the daily limit and published a book about it. Shortly after, 50 million Americans were following along.  

He eventually promoted other vitamins to prevent and treat every disease known to modern medicine, including cancer.  His pronouncements became so outrageous that he lost his scientific credibility.

The public didn’t notice and the use of vitamin supplements grew unabated.

Pauling based his treatment on anecdote, Lind based his on evidence.  

Who was right?

Vitamin C is useless in treating colds.  It may slightly reduce the duration of colds if used daily, but not the number of colds.  

As for multivitamins, there is no currently available evidence that daily use in the general population has any impact on reducing cancer, cardiovascular disease, or mortality.  

Beta-carotene, selenium, and vitamins A, C and E warrant special mention.  Not only do they have no impact in preventing disease but there is reasonable evidence that beta-carotene and vitamin E may actually increase risk of death.  

“There is no scientific basis for recommending vitamin-mineral supplements to the healthy population.”-Dr. Benjamin Caballero, MD.


4.  Offit PA. Do You Believe in Magic? The Sense and Nonsense of Alternative Medicine. New York:HarperCollins; 2013.

9.  http://www.ccjm.org/content/77/10/656

6 comments:

Anonymous said...

As for Vitamin C and colds - I rarely get a cold and I do not take vitamin supplements at all but when I feel cold symptoms coming on I take 1000 mg of Vitamin C for a couple of days and the cold symptoms disappear. I have done this for years using Redoxon which is in the form of dissolving tablets that taste like orange pop.

I have a question though regarding Vitamin D3 which I am taking once a day because I am on Arimidex which can cause bone loss and I drink lots of milk. Any thoughts on this?

Pharmadaddy said...

The comments above only apply to the general healthy population. There are many medical conditions in which vitamin supplementation is medically necessary. There are also drugs for which this is required due to nutrient depletion. The most common example is supplementation with folic acid while on methotrexate. In those individuals, as in your case, I would never recommend discontinuing the vitamins.

Anonymous said...

not about vitamins, I have flu vaccine questions. was hoping you could answer, thanks in advance for your time.
I phoned a pharmacy looking for the nasal spray vaccine for daughter age 5 that is terrified of needles. they said they have it but they will not do the dosage, it was for us to do at home. Should I be concerned about why they can not do it, will it be easy for us to do correctly at home?
also can a person receive the nasal spray or the needle vaccine when they have a minor cold with no fever?
thanks,
Tash

Pharmadaddy said...

Tash, which province are you in? I'm unsure as to why they're telling you to give it at home. Anyone with injection certification can also give FluMist. At least in Alberta. If you just have a minor cold, you should be fine. And yes, the FluMist is extremely easy to give.

Anonymous said...

We are in BC now. That is great news that its easy to do. I will pick it up and we can do it at home.
Thanks for you time, take care!

Dave said...

I'm not a great eater of fruits and vegetables, they just don't appeal to my tastes. So I know I don't eat enough of these daily.
I do take a lot of vitamins to compensate for this.
At 55 years of age I rarely get sick, perhaps once a year I get a cold that last for only a couple of days and even then the symptoms are very mild.

I've been this way, lack of illness, for 30 years. Now it might be because I have a good immune system...well of course that's why! But what keeps it so strong? Is it my mainly meat and potatoes diet? Well conventional wisdom would say no. I credit my vitamin regimen to my health...yes it's anecdotal but it works for me.