Friday, April 16, 2021

Tobacco Products’ Beneficial Antioxidant Properties


A PubMed search reveals thousands of articles on the myriad toxic chemicals present in tobacco products and smoke, but reports of health-positive tobacco attributes are rare.

In a 2000 study I co-authored with Boxin Ou of Brunswick Laboratories, we demonstrated that “manufactured tobacco products…have antioxidant capacity in moderate to high concentrations.  If these agents prove to be readily available and as easily absorbed from tobacco as nicotine, they may have demonstrable local and systemic health effects that are positive, especially for SLT users.”  The article is available here.

In our introduction, Dr. Ou and I explained why this project was important for understanding tobacco-related diseases: “The formation of reactive oxygen species (ROS) [i.e., the bad actors] alters essentially all types of biomolecules. The subsequent cellular changes induced by these reactive species are thought to play an important role in the pathogenesis of chronic diseases such as cancer and atherosclerosis.

“The consumption of fruits and vegetables is negatively correlated with mortality from cardiovascular diseases and cancer, and this protection has been attributed to the antioxidant activity in these foods. The consumption of fruits and vegetables, as well as specific foods with high antioxidant activity [i.e., anti-ROS, the good actors], results in increased plasma antioxidant capacity.

“Tobacco, consumed by 20 to 50% of the worldwide population, contains significant concentrations of polyphenols and carotenoids, which are important naturally occurring antioxidants. Cigarette smoking, the primary form of tobacco use in most societies, is correlate with low plasma antioxidant activity, a finding that may be related to the rich array of ROS that is created when tobacco is burned. Smokeless tobacco (SLT) products, in the form of chewing tobacco and moist snuff, present an alternative to tobacco combustion. SLT delivers nicotine almost as efficiently as smoking, but long-term use carries only 2% of the health risks of smoking…there is little information on the antioxidant properties of these products.”

We used a common tool called an ORAC assay to measure the antioxidant activity in tobacco products.  While we found that the highest antioxidant activity was in cigarette tobaccos, “It is known that tobacco combustion produces a chemical mix rich in ROS, and that smokers have low plasma levels of antioxidant vitamins, such as ascorbate, tocopherols and carotenoids.”

The situation is different among dippers and chewers.  They “have plasma levels of these vitamins that are similar to those of nonusers of tobacco.”  We postulated how these products’ antioxidant properties may produce positive effects: “One possible explanation for minimal cancer risk among human smokeless tobacco users and inconsistent experimental results among animal studies is that smokeless tobacco contains agents that inhibit carcinogenesis in vivo. Antioxidants present in these products remain excellent candidates for local inhibition of the effects of tobacco-specific nitrosamines [bad actors that can cause cancer] among smokeless users.”

Yes, that’s right: Tobacco products do have beneficial antioxidant properties. 



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