Second Hand Smoke: How To Alleviate The Dangers Of Second Hand Smoke

The move to ban smoking in public places seems to be gathering speed - it's certainly gained a lot of media coverage.

And a recent study in Helena, Montana, has revealed just how devastating the effects of passive smoking - or second-hand smoke - can be. But another study from the University of California suggests that the increase of a single vitamin may alleviate at least some of the dangers posed by second hand smoke.

Smoker roller coaster
The Helena case is fascinating.

In June 2002, shortly after a Helena ordinance went into effect banning smoking in all public buildings, doctors at St. Peter's Community Hospital noticed that the number of heart attack patients was dropping. Recognising a perfect opportunity, two of the doctors developed a study to examine the effects that the smoking ban might have on local heart attack statistics.

With funding from the National Cancer Institute and statistical analysis provided by researchers at the University of California, San Francisco, the St. Peter's doctors collected four years of heart attack statistics leading up to the smoking ban. Control of the study was not a problem because St. Peter's is the only cardiac care hospital in Helena. So among Helena's population of approximately 66,000, it was relatively simple to keep tabs on virtually every case of heart attack in the area.

The researchers found that within six months of the ban the Helena heart attack rate dropped by almost 60 percent compared with the average rate over the previous four years. But then the study took an unexpected twist.

The Helena smoking ban included bars, restaurants, and casinos. Immediately after the ban took effect, business in these establishments dropped off almost as sharply as the heart attack rate. So after several months of intense lobbying from tobacco interests and the Montana Tavern Association, the Montana State Legislature repealed the ban, and in December 2002 Helena residents began lighting up again over meals, drinks and slot machines.

And the rate of heart attacks in Helena returned to its previous level just as quickly as it had dropped.

Looking through smoke-coloured glasses
Yet, as we've often seen, studies need to be read very carefully to make sure the researchers' conclusions are justified by the details. Particularly with cigarette smoke being a popular public enemy #1. Unfortunately, the Helena study hasn't been published yet. So until we can review specific data and the way it was analysed, we'll still have some unanswered questions.

For instance, none of the several reports I read had data on the heart attack rates of non-smokers compared to smokers both before and after the Helena ordinance went into effect. And although we're told that variables such as seasonal fluctuations in the heart attack rate were taken into account, other variables are harder to nail down; such as the fact that some smokers tend to smoke more when they're out drinking and socialising than they do at home. Or that drinking and gambling themselves could lead to a greater number of cardiac events; and since business had dropped off at the bars and casinos, people may have cut down on those behaviours as well.

The non-smoking smoker
That said, the Helena study would appear to offer a stark reminder that no matter how healthy you may be, second hand smoke should not be taken lightly. Previous studies have revealed this general timeline of second hand smoke effects on the heart:

• 5 minutes: The aorta begins to stiffen
• 30 minutes: The blood begins to become 'sticky' with activated blood platelets; damage to the artery linings begins; blood vessel dilation is reduced
• 2 hours: Heart rhythm may become disturbed

By some estimates, an eight-hour shift spent working in a smoky casino or bar has the same effect on the cardiovascular system as smoking an entire pack of cigarettes. So in effect, a non-smoker who spends day after day in such an environment is essentially a smoker. It's called 'passive' smoking, but it's smoking nonetheless, and carries an equal risk of cancer, asthma, and heart attack that endangers everyday smokers.

Margin of safety
Fortunately, non-smokers exposed to second hand smoke may get some cardiovascular protection with an adequate intake of vitamin C.

Previous research suggests that lung cancer and cardiovascular problems triggered by passive smoking are associated with an increase in oxidative stress. A recent study from the University of California, Berkeley (UC), examined the effects of vitamin C and other nutrients on oxidative stress in 67 middle-aged non-smokers who were regularly exposed to second hand smoke.

Split into three groups, the subjects were given either 500 mg of vitamin C daily; a mix of vitamin C, E, and alpha-lipoic acid; or a placebo. After two months, researchers found that, compared to the placebo group, the vitamin C group showed a decrease in oxidative stress of more than 11 percent, and the nutrient mix group of almost 13 percent.

So can an 11, 12, or 13 percent reduction in oxidative stress protect you from a heart attack triggered by passive smoking? The answer to that would depend on many variables. But any margin of safety is welcome when the heart is exposed to the dangers of second-hand smoke.