Antioxidant supplementation does not affect fasting plasma glucose in the Supplementation with Antioxidant Vitamins and Minerals (SU.VI.MAX) study in France: association with dietary intake and plasma concentrations.
BACKGROUND
Observational data suggest a protective effect of several antioxidants on fasting plasma glucose (FPG) and type 2 diabetes. However, randomized trials have yielded inconsistent results.


OBJECTIVE
The first objective was to assess the effect of 7.5 y of antioxidant supplementation on FPG at 7.5 y. The second objective was to examine the epidemiologic association of baseline dietary intakes or plasma antioxidants and FPG (at baseline and at 7.5 y).


METHODS
Subjects (n = 3146) from the Supplementation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) primary prevention trial in France were randomly assigned to receive a daily capsule containing 120 mg vitamin C, 30 mg vitamin E, 6 mg beta-carotene, 100 mug Se, and 20 mg Zn or a placebo.


RESULTS
After 7.5 y, no significant difference was observed between age-adjusted mean FPG in men (P = 0.78) and women (P = 0.89) in either group. Baseline beta-carotene dietary intakes and plasma concentrations were inversely associated with FPG in multivariate mixed models (P = 0.0045 and P < 0.0001, respectively). Baseline plasma vitamin C and selenium were negatively (P = 0.0455) and positively (P < 0.0001) associated, respectively, with FPG.


CONCLUSIONS
Supplementation with antioxidants at nutritional doses for 7.5 y had no effect on FPG in men or women who followed a balanced diet. An inverse association of baseline beta-carotene dietary intake and plasma concentrations with FPG was found, probably because beta-carotene is an indirect marker of fruit and vegetable intakes.
Czernichow
Sébastien
S
Nutritional Epidemiology Unit, French Institute of Health and Medical Research, CRNH Ile-de-France, Bobigny, France. sebatien.czernichow@htd.aphp.fr
Couthouis
Aline
A
Bertrais
Sandrine
S
Vergnaud
Anne-Claire
AC
Dauchet
Luc
L
Galan
Pilar
P
Hercberg
Serge
S
D000975:Antioxidants / Q000008:administration & dosage* / Q000378:metabolism; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000097:blood; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism*; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000517:prevention & control; D004032:Diet; D019587:Dietary Supplements; D004311:Double-Blind Method; D005215:Fasting / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D005602:France; D006801:Humans; D008297:Male; D008875:Middle Aged; D008903:Minerals / Q000008:administration & dosage* / Q000097:blood; D015999:Multivariate Analysis; D012643:Selenium / Q000008:administration & dosage / Q000097:blood; D014810:Vitamin E / Q000008:administration & dosage / Q000097:blood; D014815:Vitamins / Q000008:administration & dosage* / Q000097:blood; D015032:Zinc / Q000008:administration & dosage / Q000097:blood; D019207:beta Carotene / Q000008:administration & dosage / Q000097:blood
D000975:Antioxidants; D001786:Blood Glucose; D008903:Minerals; D014815:Vitamins; D019207:beta Carotene; D014810:Vitamin E; D012643:Selenium; D015032:Zinc; D001205:Ascorbic Acid