Though probably not the most important health issue related to smoking tobacco, nutrient depletions are cause for concern. Tobacco (Nicotiana tabacum, N. rustica), not classically considered a medicinal herb, has been smoked in many cultures and studies show that it decreases vitamin B12 and folic acid levels. [1] Vitamin B12 is important in many biochemical processes including proper nervous system function. Vitamin B12 deficiency symptoms include bleeding gums, confusion, depression, fatigue, headaches, nausea, a sore tongue and weakness.

One study conducted at the University of Alabama, Birmingham, by Chandrika Piyathilake, Ph.D., and colleagues compared vitamin B12 and folate levels in 39 smokers and 60 nonsmokers. The smokers showed lower blood levels of vitamin B12 and folic acid than the nonsmoking subjects. [2] Smokers may also become depleted in vitamins C and E and beta-carotene as well as glutathione. [3]

Cadmium, present in tobacco, decreases the bioavailability of selenium and acts antagonistically to zinc, which is a cofactor for superoxide dismutase (SOD), the body's antioxidant enzyme.¹ Antioxidant support, especially from bilberry, grape seed extract and vitamin E, is important for smokers. You can also recommend a multivitamin along with a diet rich in green, leafy vegetables and plenty of water.

References

1. Piyathilake CJ, et al.
Cigarette smoking, intracellular vitamin deficiency, and occurrence of micronuclei in epithelial cells of the buccal mucosa.
Cancer Epidemiol Biomarkers Prev 1995;4(7):751-8.

2. Piyathilake CJ, et al.
Local and systemic effects of cigarette smoking on folate and vitamin B-12.
Am J Clin Nutr 1994;60(4):559-66.

3. Preston AM.
Cigarette smoking: nutritional implications.
Prog Food Nutr Sci 1991;15(4):183-217.