Departments of Nutrition.
Epidemiology, Harvard TH Chan School of Public Health, Boston, MA.
Am J Clin Nutr. 2019 Sep 1;110(3):574-582. doi: 10.1093/ajcn/nqz049.
Studies have found beneficial effects of plant-based diets on weight. However, not all plant foods are necessarily beneficial.
The aim of this study was to examine associations of changes in intake of 3 variations of plant-based diet indices (overall, healthful, and unhealthful) with weight change over 4-y intervals spanning >20 y.
Data from 3 ongoing prospective observational cohort studies in the United States were used, namely the Nurses' Health Study (NHS), NHS2, and the Health Professionals Follow-up Study (HPFS), with 126,982 adult men and women. Self-reported diet data were collected every 4 y, and self-reported weight data were used to compute weight change every 4 y over >20 y of follow-up.
On average, participants gained a mean of 0.90 kg (HPFS) to 1.98 kg (NHS2) over 4-y intervals. Different types of plant-based diet indices were associated with different amounts of weight gain. After adjusting for several potential confounders, including concomitant changes in other lifestyle factors, a 1-SD increase in intake of an overall plant-based diet index was associated with 0.04 kg less weight gain over 4-y periods (95% CI: 0.05, 0.02 kg; P < 0.001). A 1-SD increase in intake of a healthful version of a plant-based diet index (emphasizing whole grains, fruits/vegetables, nuts/legumes, vegetable oils, tea/coffee) was associated with 0.68 kg less weight gain over 4-y periods (95% CI: 0.69, 0.66 kg; P < 0.001). Conversely, a 1-SD increase in an unhealthful version of a plant-based diet index (emphasizing refined grains, potato/fries, sweets, sweetened drinks/juices) was associated with 0.36 kg more weight gain (95% CI: 0.34, 0.37 kg, P < 0.001).
Plant-based diets, especially when rich in healthier plant foods, are associated with less weight gain over 4-y intervals. This supports current recommendations to increase intake of healthy plant foods, and reducing intake of less-healthy plant foods and animal foods, for improved health outcomes.
研究发现，植物性饮食对体重有有益影响。然而，并非所有植物性食物都一定有益。
本研究旨在探讨 3 种植物性饮食指数（整体、健康和不健康）摄入量变化与超过 20 年跨度的 4 年体重变化之间的关联。
使用了来自美国 3 项正在进行的前瞻性观察队列研究的数据，即护士健康研究（NHS）、NHS2 和健康专业人员随访研究（HPFS），共有 126982 名成年男女。每 4 年收集一次饮食数据，每 4 年报告一次体重数据，以计算超过 20 年随访期间的体重变化。
平均而言，参与者在 4 年的间隔内平均体重增加了 0.90 公斤（HPFS）至 1.98 公斤（NHS2）。不同类型的植物性饮食指数与不同程度的体重增加有关。在调整了其他几种潜在混杂因素后，包括其他生活方式因素的同时变化，整体植物性饮食指数摄入量每增加 1 个标准差，与 4 年内体重增加 0.04 公斤相关（95%CI：0.05，0.02 公斤；P<0.001）。植物性饮食健康版本（强调全谷物、水果/蔬菜、坚果/豆类、植物油、茶/咖啡）摄入量每增加 1 个标准差，与 4 年内体重减少 0.68 公斤相关（95%CI：0.69，0.66 公斤；P<0.001）。相反，植物性饮食不健康版本（强调精制谷物、土豆/薯条、甜食、加糖饮料/果汁）摄入量每增加 1 个标准差，与体重增加 0.36 公斤相关（95%CI：0.34，0.37 公斤，P<0.001）。
植物性饮食，尤其是富含更健康植物性食物的饮食，与 4 年内体重增加较少相关。这支持了目前增加健康植物性食物摄入、减少不太健康的植物性食物和动物性食物摄入以改善健康结果的建议。
