**2.1.5 Physical activity**

26 Type 1 Diabetes – Complications, Pathogenesis, and Alternative Treatments

study design (cross-sectional), due to a substantial measurement error in the food frequency

Four cross-sectional studies reported an association between fat and/or cholesterol and nephropathy (Watts GF et al. 1988; Bouhanick B 1995; Riley MD& Dwyer T 1998; Toeller M et al. 1999 1). One study (Riley MD& Dwyer T 1998) found no significant association between energy adjusted monounsaturated fat intake or energy adjusted polyunsaturated fat intake and microalbuminuria, but reported a positive association between usual dietary saturated fat intake and microalbuminuria. Another study (Watts GF et al. 1988) found a significant positive association between total fat intake and microalbuminuria. Another study (Bouhanick B 1995) examined the relationship between fat intake and glomerular hyperfiltration (GFR > 173 ml/min/1.73m2), a marker for diabetic nephropathy, in type 1 diabetic patients. They found that excess fat intake may contribute to hyperfiltration in type 1 diabetic patients. Finally the fourth study(Toeller M et al. 1999 1) found a higher intake of cholesterol, total fat and saturated fat in Eastern Europe compared to Southern or North-Western Europe. They also found more frequent acute and chronic complications (including nephropathy) in Eastern Europe people. Since it was a cross-sectional study they could not conclude if this was due to the high intake of cholesterol, total fat and/or saturated fat. These cross-sectional studies show that there seems to be a detrimental effect of total dietary fat intake as well as saturated fat intake on type 1 diabetic nephropathy. No association between energy adjusted MUFA and energy adjusted PUFA and microalbuminuria

In a case-control study (Möllsten AV et al. 2001), no association between total fat intake and microalbuminuria was found. In a prospective study (Cárdenas C et al. 2004) a progression of nephropathy with greater saturated fatty acid (SFA) consumption and lesser polyunsaturated fatty acid consumption (PUFA) was demonstrated. Specifically with higher SFA-to-PUFA and SFA-to-MUFA ratios. Another prospective cohort study (Lee CC et al. 2010) found an association between PUFA and microalbuminuria. They found that dietary n-3 PUFAs (eicosapentaenoic acid and docosahexaenoic acid) are inversely associated with the degree but not with the incidence of albuminuria in type 1

In conclusion these prospective studies are consistent with the cross-sectional studies about the detrimental effect of saturated fat on type 1 diabetic nephropathy. The effect of total fat intake on nephropathy is still not elucidated. The cross-sectional study of Watts et al. (Watts GF et al. 1988) and the case control study of Möllsten et al. (Möllsten AV et al. 2001) were in contrast with each other. Also the effect of PUFAs on nephropathy is still doubtful, but there seems to be an inverse association between n-3 PUFAs and the degree of albuminuria.

In the EURODIAB Prospective Complications Study (Beulens et al. 2008) the association between alcohol and nephropathy was analysed cross-sectionally. They found that moderate alcohol consumers (30-70 g alcohol per week) had a lower risk of diabetic nephropathy, with an odds ratio of 0.36 (95% CI: 0.18-0.71). This association was most

questionnaires (FFQs) and due to the low response rate (61.2%) for participation.

**2.1.3 Fat/cholesterol** 

was found.

**2.1.4 Alcohol** 

diabetes (Lee CC et al. 2010).

pronounced for the consumption of wine.

There were no prospective studies on physical activity and type 1 diabetic nephropathy. One cross-sectional study (Kriska AM et al. 1991) found the lowest occurrence of diabetic nephropathy in people being 7+ hours a week physically active (sports and leisure physical activity).
