Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
JAMA Intern Med. 2020 Apr 1;180(4):513-523. doi: 10.1001/jamainternmed.2019.6980.
It is crucial to incorporate quality and types of carbohydrate and fat when investigating the associations of low-fat and low-carbohydrate diets with mortality.
To investigate the associations of low-carbohydrate and low-fat diets with total and cause-specific mortality among US adults.
DESIGN, SETTING, AND PARTICIPANTS: This prospective cohort study used data from the US National Health and Nutrition Examination Survey from 1999 to 2014 from 37 233 adults 20 years or older with 24-hour dietary recall data. Data were analyzed from July 5 to August 27, 2019.
Overall, unhealthy, and healthy low-carbohydrate-diet and low-fat-diet scores based on the percentage of energy as total and subtypes of carbohydrate, fat, and protein.
All-cause mortality from baseline until December 31, 2015, linked to National Death Index mortality data.
A total of 37 233 US adults (mean [SD] age, 49.7 [18.3] years; 19 598 [52.6%] female) were included in the present analysis. During 297 768 person-years of follow-up, 4866 total deaths occurred. Overall low-carbohydrate-diet and low-fat-diet scores were not associated with total mortality. The multivariable-adjusted hazard ratios for total mortality per 20-percentile increase in dietary scores were 1.07 (95% CI, 1.02-1.11; P = .01 for trend) for unhealthy low-carbohydrate-diet score, 0.91 (95% CI, 0.87-0.95; P < .001 for trend) for healthy low-carbohydrate-diet score, 1.06 (95% CI, 1.01-1.12; P = .04 for trend) for unhealthy low-fat-diet score, and 0.89 (95% CI, 0.85-0.93; P < .001 for trend) for healthy low-fat-diet score. The associations remained similar in the stratification and sensitivity analyses.
In this study, overall low-carbohydrate-diet and low-fat-diet scores were not associated with total mortality. Unhealthy low-carbohydrate-diet and low-fat-diet scores were associated with higher total mortality, whereas healthy low-carbohydrate-diet and low-fat-diet scores were associated with lower total mortality. These findings suggest that the associations of low-carbohydrate and low-fat diets with mortality may depend on the quality and food sources of macronutrients.
在研究低脂和低碳水化合物饮食与死亡率的关联时，将碳水化合物和脂肪的质量和类型纳入研究至关重要。
调查美国成年人中低碳水化合物和低脂肪饮食与总死亡率和死因特异性死亡率的关联。
设计、地点和参与者：本前瞻性队列研究使用了美国国家健康和营养检查调查（1999 年至 2014 年）的数据，纳入了 37233 名年龄在 20 岁或以上、有 24 小时饮食回忆数据的成年人。数据于 2019 年 7 月 5 日至 8 月 27 日进行分析。
总体而言，不健康和健康的低碳水化合物饮食和低脂肪饮食评分，基于总能量和碳水化合物、脂肪和蛋白质的亚型的百分比。
从基线到 2015 年 12 月 31 日的全因死亡率，与国家死亡指数死亡率数据相关联。
共有 37233 名美国成年人（平均[标准差]年龄，49.7[18.3]岁；19598[52.6%]为女性）纳入本分析。在 297768 人年的随访期间，共发生 4866 例总死亡。总体而言，低碳水化合物饮食和低脂肪饮食评分与总死亡率无关。多变量调整后的每 20%饮食评分增加的总死亡率的风险比为 1.07（95%置信区间，1.02-1.11；趋势 P=0.01），不健康的低碳水化合物饮食评分，0.91（95%置信区间，0.87-0.95；趋势 P<0.001），健康的低碳水化合物饮食评分，1.06（95%置信区间，1.01-1.12；趋势 P=0.04），不健康的低脂肪饮食评分，0.89（95%置信区间，0.85-0.93；趋势 P<0.001），健康的低脂肪饮食评分。在分层和敏感性分析中，这些关联仍然相似。
在这项研究中，总体低碳水化合物饮食和低脂肪饮食评分与总死亡率无关。不健康的低碳水化合物饮食和低脂肪饮食评分与较高的总死亡率相关，而健康的低碳水化合物饮食和低脂肪饮食评分与较低的总死亡率相关。这些发现表明，低碳水化合物和低脂肪饮食与死亡率的关联可能取决于宏量营养素的质量和食物来源。
