A US study showed that improved diet quality over 12 years was consistently associated with a decreased risk of death. The study used Cox proportional-hazards models to calculate adjusted hazard ratios for total and cause-specific mortality among 47,994 women and 25,745 men from 1998 through 2010, with changes in diet quality over the preceding 12 years (1986–1998). The pooled hazard ratios for all-cause mortality among participants who had the greatest improvement in diet quality (13 to 33% improvement), as compared with those who had a relatively stable diet quality (0 to 3% improvement), in the 12-year period were 0.91 to 0.84. A 20-percentile increase in diet scores (indicating an improved quality of diet) was significantly associated with a reduction in total mortality of 8 to 17% with the use of three diet indexes and a 7 to 15% reduction in the risk of death from cardiovascular disease with the use of the Alternate Healthy Eating Index and Alternate Mediterranean Diet. Among participants who maintained a high-quality diet over a 12-year period, the risk of death from any cause was significantly lower — by 9-14% when assessed with the 3 diet indexes — than the risk among participants with consistently low diet scores over time. The results are consistent with the findings of another study that healthier plant foods are associated with substantially lower risk of coronary heart disease. Source: http://www.nejm.org/; http://www.onlinejacc.org/
