Compliance, tolerability and safety of two antioxidant-rich diets: A randomised controlled trial in male smokers

TY - JOUR

T1 - Compliance, tolerability and safety of two antioxidant-rich diets

T2 - A randomised controlled trial in male smokers

AU - Karlsen, Anette

AU - Svendsen, Mette

AU - Seljeflot, Ingebjørg

AU - Sommernes, Mary Ann

AU - Sexton, Joseph

AU - Brevik, Asgeir

AU - Erlund, Iris

AU - Serafini, Mauro

AU - Bastani, Nasser

AU - Fagertun Remberg, Siv

AU - Borge, Grethe I

AU - Hauger Carlsen, Monica

AU - Kjølsrud Bøhn, Siv

AU - Myhrstad, Mari C

AU - Dragsted, Lars Ove

AU - Duttaroy, Asim K

AU - Haffner, Karin

AU - Laake, Petter

AU - Drevon, Christan A

AU - Arnesen, Harald

AU - Collins, Andrew

AU - Tonstad, Serena

AU - Blomhoff, Rune

PY - 2011

Y1 - 2011

N2 - 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.

AB - 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.

KW - Antioxidant network

KW - Dietary antioxidants

KW - Oxidative stress

KW - Plasma antioxidants

U2 - 10.1017/s0007114511000353

DO - 10.1017/s0007114511000353

M3 - Journal article

C2 - 21806852

AN - SCOPUS:80053022311

SN - 0007-1145

VL - 106

SP - 557

EP - 571

JO - British Journal of Nutrition

JF - British Journal of Nutrition

IS - 4

ER -