改变饮食习惯并改善饮食健康
2016年6月21日，《美国医学会杂志》发表纽约蒙蒂菲奥里医学中心、塔夫茨大学弗里德曼营养科学与政策学院、华盛顿大学健康指标与评估研究所在1999～2012年间开展的全国代表性调查研究报告，发现自我报告的饮食习惯有数项改善得到确认，例如：全谷类消耗增加；而其他发现提示，基于种族、民族、教育和收入水平的差异持续存在或有所加剧。
次优饮食是造成健康不佳的主要原因之一，尤其是肥胖症、糖尿病、心血管疾病和与饮食相关癌症。在美国，据估计，饮食因素造成每年超过65万人死亡，占所有伤残校正生命年丧失的14%。了解饮食习惯的发展趋势对提供改善饮食的要务和政策信息及减少饮食相关疾病都是至关重要的。该研究对主要疾病相关性总体饮食品质和多重饮食成分趋势进行调查，使用全国代表性样本24小时膳食回顾，样本包括33932位美国成人，其年龄≥20岁，来自7个周期（1999～2012）全国健康与营养调查（NHANES）。作为综合指标，饮食评分基于美国心脏学会（AHA）2020年饮食策略影响目标构建。
该研究发现，美国饮食的许多方面都有改善，其中包括全谷类、坚果或种子消耗增加、鱼和贝类消耗略有增加、含糖或加糖饮料消耗减少。其他饮食趋势包括完整水果消耗增加，100%水果汁消耗下降。其他饮食评分成分则没有观察到明显的发展趋势，其中包括完整水果和蔬菜、加工肉类、饱和脂肪及盐分。美国成人中估计的不良饮食百分比从56%下降至46%。理想饮食百分比有所增加，但仍然处于低水平（从0.7%增加至1.5%）。
在不同种族、民族、教育和收入水平的人群中观察到了饮食品质的差异；例如，在非西班牙语裔白人成年者中，不良饮食的估计百分比显著下降（54%至43%），而在非西班牙语裔黑人或墨西哥裔美国成人中则没有观察到类似改善。没有证据显示这些差异有所减少，而有证据显示，收入水平所致差异有所加大。
对此，德克萨斯大学西南医学中心的内科专家发表同期述评：改变并改善美国的饮食习惯和饮食健康。
JAMA. 2016 Jun 21;315(23):2542-53.
Dietary Intake Among US Adults, 1999-2012.
Rehm CD, Penalvo JL, Afshin A, Mozaffarian D.
Office of Community and Population Health, Montefiore Medical Center, Bronx, New York; Tufts Friedman School of Nutrition Science and Policy, Boston, Massachusetts; Institute for Health Metrics and Evaluation, Department of Global Health, University of Washington, Seattle.
IMPORTANCE: Most studies of US dietary trends have evaluated major macronutrients or only a few dietary factors. Understanding trends in summary measures of diet quality for multiple individual foods and nutrients, and the corresponding disparities among population subgroups, is crucial to identify challenges and opportunities to improve dietary intake for all US adults.
OBJECTIVE: To characterize trends in overall diet quality and multiple dietary components related to major diseases among US adults, including by age, sex, race/ethnicity, education, and income.
DESIGN, SETTING, AND PARTICIPANTS: Repeated cross-sectional investigation using 24-hour dietary recalls in nationally representative samples including 33,932 noninstitutionalized US adults aged 20 years or older from 7 National Health and Nutrition Examination Survey (NHANES) cycles (1999-2012). The sample size per cycle ranged from 4237 to 5762.
EXPOSURES: Calendar year and population sociodemographic subgroups.
MAIN OUTCOMES AND MEASURES: Survey-weighted, energy-adjusted mean consumption and proportion meeting targets of the American Heart Association (AHA) 2020 continuous diet scores, AHA score components (primary: total fruits and vegetables, whole grains, fish and shellfish, sugar-sweetened beverages, and sodium; secondary: nuts, seeds, and legumes, processed meat, and saturated fat), and other individual food groups and nutrients.
RESULTS: Several overall dietary improvements were identified (P < .01 for trend for each). The AHA primary diet score (maximum of 50 points) improved from 19.0 to 21.2 (an improvement of 11.6%). The AHA secondary diet score (maximum of 80 points) improved from 35.1 to 38.5 (an improvement of 9.7%). Changes were attributable to increased consumption between 1999-2000 and 2011-2012 of whole grains (0.43 servings/d; 95% CI, 0.34-0.53 servings/d) and nuts or seeds (0.25 servings/d; 95% CI, 0.18-0.34 servings/d) (fish and shellfish intake also increased slightly) and to decreased consumption of sugar-sweetened beverages (0.49 servings/d; 95% CI, 0.28-0.70 servings/d). No significant trend was observed for other score components, including total fruits and vegetables, processed meat, saturated fat, or sodium. The estimated percentage of US adults with poor diets (defined as <40% adherence to the primary AHA diet score components) declined from 55.9% to 45.6%, whereas the percentage with intermediate diets (defined as 40% to 79.9% adherence to the primary AHA diet score components) increased from 43.5% to 52.9%. Other dietary trends included increased consumption of whole fruit (0.15 servings/d; 95% CI, 0.05-0.26 servings/d) and decreased consumption of 100% fruit juice (0.11 servings/d; 95% CI, 0.04-0.18 servings/d). Disparities in diet quality were observed by race/ethnicity, education, and income level; for example, the estimated percentage of non-Hispanic white adults with a poor diet significantly declined (53.9% to 42.8%), whereas similar improvements were not observed for non-Hispanic black or Mexican American adults. There was little evidence of reductions in these disparities and some evidence of worsening by income level.
CONCLUSIONS AND RELEVANCE: In nationally representative US surveys conducted between 1999 and 2012, several improvements in self-reported dietary habits were identified, with additional findings suggesting persistent or worsening disparities based on race/ethnicity, education level, and income level. These findings may inform discussions on emerging successes, areas for greater attention, and corresponding opportunities to improve the diets of individuals living in the United States.
PMID: 27327801
DOI: 10.1001/jama.2016.7491
JAMA. 2016 Jun 21;315(23):2527-9.
Changing Dietary Habits and Improving the Healthiness of Diets in the United States.
Denke MA.
University of Texas Southwestern Medical Center, Dallas.
PMID: 27327799
DOI: 10.1001/jama.2016.7636