Prospective association between the Dietary Inflammatory Index and mortality: modulation by antioxidant supplementation in the SU.VI.MAX randomized controlled trial.
Study Goal
The researchers aimed to study the association between the Dietary Inflammatory Index (DII) and mortality, and whether antioxidant supplementation could modulate this association.
Results Summary
A proinflammatory diet was associated with increased all-cause and cancer mortality, and antioxidants appeared to counteract some of these proinflammatory effects, particularly in the placebo group where the DII was significantly linked to higher mortality.
Population
8089 participants (mean age 49.0 ± 6.3 years) from the Supplémentation en Vitamines et Minéraux Antioxydants study.
Effective Dosage
Low-dose antioxidants (specific dosage not mentioned).
Duration
1994 to 2002 (median follow-up: 12.4 years).
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
proinflammatory diet (higher Dietary Inflammatory Index score) | increase | cardiovascular + cancer mortality | participants in the Supplémentation en Vitamines et Minéraux Antioxydants study | HR for tertile 3 compared with tertile 1 = 1.53; 95% CI: 1.01, 2.32 | positively associated with | #1 |
proinflammatory diet (higher Dietary Inflammatory Index score) | increase | specific cancer mortality | participants in the Supplémentation en Vitamines et Minéraux Antioxydants study | HR for tertile 3 compared with tertile 1 = 1.83; 95% CI: 1.12, 2.99 | positively associated with | #2 |
proinflammatory diet (higher Dietary Inflammatory Index score) | increase | all-cause mortality | placebo group | HR for tertile 3 compared with tertile 1 = 2.10; 95% CI: 1.15, 3.84 | statistically significantly associated with increased | #3 |
proinflammatory diet (higher Dietary Inflammatory Index score) | no change | all-cause mortality | antioxidant-supplemented group | P-trend = 0.8 | not associated with | #4 |
low-dose antioxidant supplementation | decrease | mortality association | participants in the Supplémentation en Vitamines et Minéraux Antioxydants study | - | may counteract some of the proinflammatory effects of the diet | #5 |
BACKGROUND: Chronic inflammation is a central mechanism involved in cardiovascular diseases, cancer, diabetes, and chronic respiratory diseases, 4 leading causes of mortality. Diet is a major source of pro- and anti-inflammatory bioactive compounds. The Dietary Inflammatory Index (DII) was designed to estimate the overall inflammatory potential of the diet. OBJECTIVE: Our aim was to study the prospective association between the DII and mortality, as well as assess whether antioxidant supplementation could modulate this association. DESIGN: The Supplémentation en Vitamines et Minéraux Antioxydants study was a randomized, double-blind, placebo-controlled trial in which participants received low-dose antioxidants or a placebo from 1994 to 2002. In this observational prospective analysis, 8089 participants (mean ± SD age at baseline: 49.0 ± 6.3 y) were followed between 1994 and 2007 (median: 12.4 y). The DII was calculated from repeated 24-h dietary records; higher scores correspond to more proinflammatory diets. A total of 207 deaths occurred during follow-up, including 123 due to cancer and 41 due to cardiovascular events. Multivariate Cox proportional hazards models were computed. RESULTS: Sex-specific tertiles of the DII were positively associated with cardiovascular + cancer mortality (HR for tertile 3 compared with tertile 1 = 1.53; 95% CI: 1.01, 2.32; P-trend = 0.05) and specific cancer mortality (HR for tertile 3 compared with tertile 1 = 1.83; 95% CI: 1.12, 2.99; P-trend = 0.02). The corresponding P value was 0.07 for all-cause mortality. The DII was statistically significantly associated with increased all-cause mortality in the placebo group (HR for tertile 3 compared with tertile 1 = 2.10; 95% CI: 1.15, 3.84; P-trend = 0.02) but not in the antioxidant-supplemented group (P-trend = 0.8; P-interaction = 0.098). CONCLUSION: These results suggest that a proinflammatory diet is associated with increased all-cause and cancer mortality and antioxidants may counteract some of the proinflammatory effects of the diet. This trial was registered at clinicaltrials.gov as NCT00272428.