Long-Term Change in both Dietary Insulinemic and Inflammatory Potential Is Associated with Weight Gain in Adult Women and Men.

BACKGROUND

The influence of long-term dietary patterns on weight gain and the underlying potential biological mechanisms are not fully understood.

OBJECTIVE

We prospectively examined the association of changes in 2 empirical hypothesis-oriented dietary patterns (insulinemic and inflammatory) and weight gain over 24 y at 4-y intervals.

METHODS

We followed 54,397 women in the Nurses' Health Study and 33,043 men in the Health Professionals Follow-Up Study (1986-2010), and computed the empirical dietary index for hyperinsulinemia (EDIH) and empirical dietary inflammatory pattern (EDIP) scores from food frequency questionnaires administered every 4 y. Both scores are weighted sums of 18 food groups, which characterize dietary insulinemic or inflammatory potential based on plasma levels of insulin response or inflammatory biomarkers. We used multivariable-adjusted linear regression to examine 4-y changes in the dietary scores and weight change within the same period.

RESULTS

The mean baseline body mass index (BMI, in kg/m2) was 25.4. Compared with participants who made minimal dietary changes (quintile 3) over 6 4-y periods; participants who changed their diets toward lower insulinemic or inflammatory potential (quintile 1) gained significantly less weight (in kilograms per 4 y) independent of total energy intake, BMI, physical activity, and smoking status: EDIH: -0.65 (95% CI: -0.73, -0.57), EDIP: -0.29 (-0.37, -0.21) among women; and EDIH: -0.60 (-0.71, -0.49), EDIP: -0.19 (-0.27, -0.07) among men. In contrast, those who changed their diets toward higher insulinemic or inflammatory potential (quintile 5) gained significantly more weight: EDIH: 0.43 (0.36, 0.51), EDIP: 0.15 (0.07, 0.23) among women; and EDIH: 0.49 (0.38, 0.59), EDIP: 0.22 (0.11, 0.33) among men (P-trend < 0.0001 for all comparisons). Associations were stronger among individuals who were overweight or obese, younger, less physically active, and had never smoked.

CONCLUSIONS

High dietary insulinemic and inflammatory potential is associated with substantial long-term weight gain in adult men and women independent of total energy intake. Dietary patterns with low insulinemic and inflammatory potential may aid in weight gain prevention.