Abstract
The Healthy Eating Index-2005 (HEI-2005) measures adherence to the 2005 Dietary Guidelines for Americans, but the association between the HEI-2005 and risk of chronic disease is not known. The Alternative Healthy Eating Index (AHEI), which is based on foods and nutrients predictive of chronic disease risk, was associated inversely with chronic disease risk previously. We updated the AHEI, including additional dietary factors involved in the development of chronic disease, and assessed the associations between the AHEI-2010 and the HEI-2005 and risk of major chronic disease prospectively among 71,495 women from the Nurses’ Health Study and 41,029 men from the Health Professionals Follow-Up Study who were free of chronic disease at baseline. During ≥24 y of follow-up, we documented 26,759 and 15,558 incident chronic diseases (cardiovascular disease, diabetes, cancer, or nontrauma death) among women and men, respectively. The RR (95% CI) of chronic disease comparing the highest with the lowest quintile was 0.84 (0.81, 0.87) for the HEI-2005 and 0.81 (0.77, 0.85) for the AHEI-2010. The AHEI-2010 and HEI-2005 were most strongly associated with coronary heart disease (CHD) and diabetes, and for both outcomes the AHEI-2010 was more strongly associated with risk than the HEI-2005 (P-difference = 0.002 and <0.001, respectively). The 2 indices were similarly associated with risk of stroke and cancer. These findings suggest that closer adherence to the 2005 Dietary Guidelines may lower risk of major chronic disease. However, the AHEI-2010, which included additional dietary information, was more strongly associated with chronic disease risk, particularly CHD and diabetes. J. Nutr. 142: 1009-1018, 2012.
Generated Summary
This research presents a prospective cohort study examining the associations between the Healthy Eating Index-2005 (HEI-2005) and the updated Alternative Healthy Eating Index (AHEI-2010) with the risk of major chronic diseases. The study included 71,495 women from the Nurses’ Health Study and 41,029 men from the Health Professionals Follow-Up Study. The participants were initially free of chronic diseases. The study used the FFQ (Food Frequency Questionnaire) to collect dietary data. The primary objective of the study was to assess how closely adhering to the 2005 Dietary Guidelines, measured through HEI-2005, related to chronic disease risk. Additionally, it aimed to evaluate the effectiveness of AHEI-2010, a dietary assessment tool based on foods and nutrients associated with chronic disease risk, and its association with major chronic diseases, including cardiovascular disease, diabetes, and cancer, over an extended follow-up period. The research also provided a comparison between the two indices in their predictive power for these diseases. The study applied the Cox proportional hazards models with adjustments for multiple confounders. This approach allowed the researchers to assess the relative risks (RRs) of chronic diseases associated with different levels of adherence to the HEI-2005 and AHEI-2010.
Key Findings & Statistics
- General Outcomes: The study documented 26,759 and 15,558 incident chronic diseases (cardiovascular disease, diabetes, cancer, or nontrauma death) among women and men, respectively, during the follow-up period.
- HEI-2005 and Chronic Disease Risk: The RR (95% CI) of chronic disease comparing the highest with the lowest quintile was 0.84 (0.81, 0.87) for the HEI-2005.
- AHEI-2010 and Chronic Disease Risk: The RR (95% CI) of chronic disease comparing the highest with the lowest quintile was 0.81 (0.77, 0.85) for the AHEI-2010.
- Correlation between Diet Scores: The correlation between HEI-2005 and AHEI-2010 scores was high (r = 0.65, P < 0.001 in women; r = 0.68, P < 0.001 in men).
- Risk of Major Chronic Disease (HEI-2005):The HEI-2005 was significantly inversely associated with risk of major chronic disease, including total CVD, CHD, stroke, diabetes, and total cancer, among both women and men (P-trend < 0.001).
- Risk of Major Chronic Disease (AHEI-2010): The AHEI-2010 was associated inversely with the risk of major chronic disease in both women and men in age-adjusted and multivariate models (P-trend < 0.001 for both).
- Pooled RR for Major Chronic Disease: For both the AHEI and AHEI-2010, the RR of major chronic disease comparing the highest with the lowest quintile was 0.81 (95% CI: 0.77, 0.85).
- Cardiovascular Disease Risk (AHEI-2010): Higher AHEI-2010 scores were inversely associated with the risk of CVD (P-trend < 0.001).
- CHD vs. Stroke (AHEI-2010): The AHEI-2010 was more strongly associated with the risk of CHD than stroke.
- Diabetes Risk (AHEI-2010): The AHEI-2010 was inversely associated with the risk of diabetes (Table 3).
- Cancer Risk (AHEI-2010): The AHEI-2010 was inversely associated with risk of total cancer in women (P-trend = 0.01) but not in men (P-trend = 0.13). However, in pooled analysis, the AHEI-2010 was inversely associated with cancer (P-trend = 0.003).
- Comparison of HEI-2005 and AHEI-2010: The AHEI-2010 was more strongly associated with the risk of major chronic disease than the HEI-2005 (P-difference in diet scores < 0.001).
- CHD and Diabetes (AHEI-2010): The AHEI-2010 was more strongly associated with risk of CHD (P-difference between diet scores = 0.002) and diabetes (P-difference between diet scores < 0.001).
- Individual Components of HEI-2005 and AHEI-2010: Components of HEI-2005 independently associated with lower risk of major chronic disease were dark-green and orange vegetables, whole fruit, and whole grains, along with a low intake of sodium. For the AHEI-2010, a higher intake of whole grains, nuts, and alcoholic beverages and a lower intake of sugar-sweetened beverages and red/processed meats were associated with lower risk of major chronic disease.
Other Important Findings
- The AHEI-2010 was more strongly associated with risk of CHD (P-difference between diet scores = 0.002) and diabetes (P-difference between diet scores < 0.001).
- The association between the AHEI-2010 and risk of CHD and diabetes was not attenuated and remained significant after adjustment for the HEI-2005.
- Conversely, the HEI-2005 was not significantly associated with risk of CHD or diabetes after adjustment for the AHEI-2010.
- For both stroke and cancer, we did not detect significance differences in association between the diet scores (P-difference in diet scores: 0.87 for stroke and 0.23 for cancer).
- Components of the HEI-2005 that were independently associated with lower risk of major chronic disease were dark-green and orange vegetables, whole fruit, and whole grains and to a lesser extent total grains, milk, vegetable oils, and a low intake of sodium.
- For the AHEI-2010, a higher intake of whole grains, nuts, and alcoholic beverages and a lower intake of sugar-sweetened beverages and red/processed meats were associated with lower risk of major chronic disease.
Limitations Noted in the Document
- The dietary quality within these cohorts of mostly white, well-educated health professionals may not be representative of the dietary quality in the United States.
- The analyses were based on the 2005 Dietary Guidelines, which were recently updated (60). The HEI-2010 has not been released, and thus we cannot assess adherence to the most recent guidelines.
- Many lifestyle factors play an important role in the development of chronic disease and may confound the association between diet quality and disease risk.
- Residual confounding remains possible despite controlling for these factors in the analysis.
- The educational and occupational homogeneity of this population minimizes variation in factors related to socioeconomic status that are associated with diet quality and could potentially confound our results.
Conclusion
The study provides important insights into the relationship between dietary patterns and chronic disease risk. The findings suggest that adhering to the 2005 Dietary Guidelines can reduce the risk of major chronic diseases, offering support for current dietary recommendations. The AHEI-2010, with its emphasis on specific food choices, showed a stronger association with risk reduction, especially for CHD and diabetes, compared to the HEI-2005. This highlights the potential benefits of refining dietary guidelines to emphasize specific food choices associated with lower chronic disease risk. The AHEI-2010’s focus on whole grains, nuts, and fish, along with reduced intake of red/processed meats and sugar-sweetened beverages, underscores the importance of food quality. The study’s results are significant because they underscore the importance of food choices in reducing chronic disease risk. The greater adherence to the 2005 guidelines may reduce the risk of major chronic diseases, including CHD, stroke, diabetes, and total cancer. The AHEI-2010, which explicitly emphasizes high intakes of whole grains, PUFA, nuts, and fish and reductions in red and processed meats, refined grains, and sugar-sweetened beverages, was also associated with lower risk of chronic diseases; in models that adjusted for both scores, the AHEI-2010 was more strongly associated with CHD and diabetes. It suggests that future revisions of Dietary Guidelines may consider special emphasis on selecting the healthiest choices within each food group, specifically high-quality grains (whole vs. refined grains) and protein sources (nuts/beans/fish vs. red/processed meats), and encouraging greater intake of PUFA and reducing intake of sugar-sweetened beverages. The conclusion reinforces the need for updated dietary guidelines that focus on specific food choices to further reduce the risk of chronic disease, especially CHD and diabetes.