Taking a specific form of a vitamin E supplement can accelerate the health benefits that occur when people quit smoking, according to new research.
US researchers found that the improvement in blood vessel function associated with the added vitamin E in the study participants could drop the future risk for cardiovascular disease by an estimated 19 per cent.
Smokers were recruited to participate in a study to quit smoking for seven days, with blood markers of inflammation and blood vessel function measured before and after the trial.
After seven days of not smoking, participants saw an increase in their vascular function by an average of 2.8 per cent. Those who quit smoking and also took the gamma-tocopherol form of vitamin E showed a 1.5 per cent additional improvement in vascular function.
While these changes in vascular function may appear to be small, previous large-scale studies suggest that every 1 per cent increase in vascular function - or improvement in the blood vessel's ability to dilate - translates into a 13 per cent drop in risk of developing heart disease later in life.
"This is a very short-term study that shows very promising effects," said Richard Bruno from The Ohio State University and senior author of the study.
"The underlying rationale is that we know it takes many years before the risk for cardiovascular disease of a former smoker matches that of a nonsmoker. We hope to develop a therapy to combine with smoking cessation that could accelerate the restoration of vascular function and reduce cardiovascular risk," Bruno said.
The supplement in the study is not the same as the average vitamin E available on most store shelves. Vitamin E occurs in eight forms based on their chemical structure, and the most well-known form belongs to a variety called tocopherols.
In this study, researchers tested the effects of the gamma-tocopherol form. The most common form of vitamin E, and the one for which humans have a dietary requirement, is alpha-tocopherol.
Though taking gamma-tocopherol is safe, Bruno noted that longer-term studies with more participants would be required to nail down specific dietary recommendations related to smoking cessation.
A total of 30 smokers in their 20s who had smoked at least half a pack per day for a year participated in the study. All participants stopped smoking, and 16 received 500 milligrammes daily of gamma-tocopherol while 14 received a placebo.
Participants who took the supplements showed greater improvements in vascular function and also had lower levels of two inflammation-related proteins in their blood than did participants who received a placebo.
Bruno said the lower levels of those two proteins in the supplemented participants' blood suggest that the gamma-tocopherol form of vitamin E restores vascular function at least in part by lowering inflammation.
