It is well known that tobacco smoke contains many highly reactive oxygen species (such as hydrogen peroxide) which cause oxidative damage to any tissue that they come into contact with. The free radicals in tobacco smoke cause significant damage to vascular tissue (arteries, veins etc) and may eventually lead to damage to the blood brain barrier. It is already known that tobacco smoke can lead to significantly decreased levels of vitamin E and vitamin C in the blood plasma of smokers due to increased anti-oxidative responses to the elevated levels of reactive oxygen species.

The researchers found that pre-treatment with the antioxidant vitamins E & C can help to reduce some of the pro-inflammatory response caused by the reactive oxygen species found in tobacco smoke. The researchers suggested that “it very likely that higher concentrations and/or a sustained supplementation of vitamin C are necessary to maintain a protective effect for a longer period of time.” – possibly around 200mg/day for smokers.

It was also demonstrated that vitamin C’s protective effect was significantly enhanced, both in efficacy and duration, when combined with vitamin E. The researchers concluded that “These antioxidant vitamins may act synergistically in preventing oxidative damage and pro-inflammatory stimulation induced by tobacco smoking exposure, thereby reducing TS toxicity at the BBB level.”