Comparison of the diet of self-declared diabetics with non-diabetic patients in the SU.VI.MAX study: did the diabetics modify their nutritional behavior?

Objective: Dietary recommendations, a pillar in the treatment of diabetes, form part of official guidelines. However, it is not known how well these recommendations are followed in the diabetic population in France. The purpose of this study was to compare the habitual diet of self-declared diabetics with non-diabetics and to evaluate whether recommendations are being followed.

Methods: The intakes of several nutrients and foods of 67 self-declared diabetic patients were compared to those of 4658 non-diabetics in the SU.VI.MAX study (a primary prevention trial evaluating the impact of antioxidant supplementation on chronic disease). All patients (aged 45 to 60 years) who had completed at least five 24-hr dietary records over the first 18 months of the SU.VI.MAX study were included. We excluded patients who had not declared a diagnosis of diabetes and those with plasma fasting glucose levels over 7 mmol/l.

Results: The diabetic patients who declared being diabetic reported lower carbohydrate intakes (185 +/- 10.4 vs 219 +/- 1.4 g/d for men [p=0.001], 137 +/- 9.6 vs 165 +/- 1.0 g/d for women [0.005]), with a 50% reduction in consumption of oligosaccharides. Lipid intakes were unchanged for men, but reduced for women (61 +/- 4.1 g/d vs 72 +/- 0.4 g/d [p=0.01] with a 20% reduction in saturated fatty acids. Protein consumption was higher in the diabetic than in the non-diabetic men, but comparable for the women. Energy intakes were only lower in the diabetic women (1458 +/- 81 vs 1665 +/- 9 Kcal/d for women [p=0.01]). Micronutrient intakes were similar to those of non-diabetics, but appeared to be inadequate, particularly for anti-oxidants. Diabetic men consumed more margarine and less alcohol than did the non-diabetics.

Conclusion: Diabetic patients who declared being diabetic did modify their nutritional behaviour, as they reduced their carbohydrate intake (both men and women), increased their protein intake (men only), and decreased their lipid and energy intakes (women only). However, carbohydrate intakes were unbalanced and there was excess protein intake. So patients who declared being diabetic are not as non-compliant in nutrition as commonly thought; they try to modify their diet, but often inappropriately. This may be explained by the fact that dietary advice stems from different sources and may be contradictory. A diabetic education program requires standardised training of health professionals and the provision of unequivocal information to the mass media and the general public.