Department of Nutrition, Faculty of Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
Br J Nutr. 2011 Aug;106(4):557-71. doi: 10.1017/S0007114511000353.
It has been suggested that antioxidants attenuate oxidative stress and prevent oxidative stress-related diseases. Paradoxically, randomised controlled trials (RCT) using pharmacological doses of antioxidant supplements have demonstrated harmful effects in smokers. The aim of the present study was to test the compliance, tolerability and safety of two food-based antioxidant-rich diets in smokers. One of the diets provided antioxidants at levels similar to that used in RCT using supplements which previously have generated harmful effects. The present study followed a randomised, parallel-arm dietary intervention for 8 weeks (n 102) in male smokers (age ≥ 45 years). Participants were randomised to either antioxidant-rich diet, kiwi fruit or control groups. The antioxidant-rich foods provided about 300 mmol antioxidants/week from a wide range of plant-based food items. The kiwi fruit group consumed three kiwi fruits/d. Compliance to both diets was good. Only mild, undesirable events were reported by a minority of the participants. The safety of both diets was demonstrated as no potentially harmful or pro-oxidative effects were observed. In the antioxidant-rich diet group, the mean intake of antioxidants increased from 30 mmol/d at baseline to 62 mmol/d during the intervention. In conclusion, we have demonstrated that male smokers can comply with two food-based antioxidant-rich diets. Furthermore, the present study is the first to demonstrate the tolerability and safety of dietary antioxidants at levels similar to dosages provided in RCT using supplements. Such diets may be useful in future studies investigating whether dietary antioxidants may reduce oxidative stress and related diseases.
有人认为抗氧化剂可以减轻氧化应激并预防与氧化应激相关的疾病。但具有矛盾性的是，使用药理学剂量的抗氧化补充剂进行的随机对照试验（RCT）表明，这些补充剂对吸烟者有有害影响。本研究旨在测试两种富含抗氧化剂的食物在吸烟者中的依从性、耐受性和安全性。其中一种饮食提供的抗氧化剂水平与使用以前产生有害影响的补充剂进行的 RCT 中使用的水平相似。本研究采用随机、平行臂饮食干预，对 102 名男性吸烟者（年龄≥45 岁）进行了 8 周的研究。参与者被随机分配到富含抗氧化剂的饮食、猕猴桃组或对照组。富含抗氧化剂的食物提供了约 300mmol 抗氧化剂/周，来自广泛的植物性食物。猕猴桃组每天食用三个猕猴桃。两种饮食的依从性都很好。只有少数参与者报告了轻微的不良事件。两种饮食的安全性均得到证明，因为没有观察到潜在的有害或促氧化作用。在富含抗氧化剂的饮食组中，抗氧化剂的平均摄入量从基线时的 30mmol/d 增加到干预期间的 62mmol/d。总之，我们已经证明，男性吸烟者可以遵守两种富含抗氧化剂的食物饮食。此外，本研究首次证明了在 RCT 中使用补充剂提供的剂量相似的饮食抗氧化剂的耐受性和安全性。这种饮食可能对未来研究是否可以减少氧化应激和相关疾病有用。
