Daily consumption of apple, pear and orange juice differently affects plasma lipids and antioxidant capacity of smoking and non-smoking adults

Epidemiological studies have shown an inverse correlation between a fruit and vegetable-rich diet and cardiovascular diseases; this beneficial effect of fruits and vegetables is probably due to the presence of antioxidant phytochemicals. In contrast, cigarette smoking is a high risk factor for lung and heart diseases, associated with chronic oxidative stress. In the present study, the effect of the consumption of a pear, an apple and 200 ml orange juice, during 26 days, on total plasma antioxidant capacity (TAC) and lipid profile of chronic smokers and non-smoking healthy adults was analyzed. Fruit consumption increased TAC in non-smokers, but not in smokers. In non-smokers, total cholesterol, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol increased significantly; while in smokers, total cholesterol and low-density lipoprotein-cholesterol decreased. We may conclude fruit/juice supplementation showed different effects, depending on the smoking habit: in non-smokers it increased TAC and cholesterol; in smokers it reduced cholesterol, whithout inducing a TAC increase.