Department of Dental Public Health, Faculty of Dentistry, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
Center for Nutrition, Healthy Lifestyle & Disease Prevention, School of Public Health, Loma Linda University, Loma Linda, CA 92350, USA.
Nutrients. 2022 Feb 28;14(5):1017. doi: 10.3390/nu14051017.
The aim of this article is to evaluate the effect of a daily supplement of walnuts on the overall daily diet and nutrient profile of healthy adults. A randomized controlled trial with crossover design was conducted for two 6-month diet periods in southeast Californian communities. Subjects were randomized to receive a control diet or a walnut-supplemented diet, then switched. The walnut supplement represented approximately 12% of their daily energy intake. Trained nutritionists collected seven 24 h dietary recalls from each participant (a total of 14 recalls for both periods). Ninety participants were able to complete the study, including 50 females and 40 males. The average age of the participants was 54.3 years. Diets in the walnut period had significantly higher vegetable protein, total fat, total PUFA, PUFA 18:2, PUFA 22:6, and total dietary fiber (p < 0.05), while also exhibiting significantly lower PUFA 20:5. All mineral levels were higher on the walnut-supplemented diet. Calcium, phosphorus, magnesium, and zinc were, particularly, significantly higher among the walnut-supplemented group (p < 0.05). Displacement occurred in more than one-third of the entire nuts and seeds group; four-fifths of the non-alcoholic beverages and desserts groups; and the majority of the candy, sugar, and sweets group. Walnut supplementation can lead to favorable modifications in nutrient and food intake profiles that may contribute to chronic disease prevention. Nutrient and food displacement may be a mechanism to explain the favourable association between walnut intake and improved diet.
本文旨在评估每日食用核桃对健康成年人整体日常饮食和营养状况的影响。在加利福尼亚东南部社区进行了一项为期 6 个月的随机对照交叉试验。研究对象被随机分配到接受对照饮食或核桃补充饮食组，然后进行交换。核桃补充剂占他们日常能量摄入的 12%左右。经过培训的营养师从每位参与者收集了 7 份 24 小时膳食回忆（两个时期共 14 份回忆）。90 名参与者完成了研究，其中包括 50 名女性和 40 名男性。参与者的平均年龄为 54.3 岁。在核桃期，饮食中的蔬菜蛋白、总脂肪、总多不饱和脂肪酸、PUFA 18:2、PUFA 22:6 和总膳食纤维显著增加（p<0.05），而 PUFA 20:5 则显著降低。所有矿物质水平在核桃补充饮食中均升高。钙、磷、镁和锌在核桃补充组中尤其显著升高（p<0.05）。在整个坚果和种子组中，超过三分之一的食物被取代；在非酒精饮料和甜点组中，五分之四的食物被取代；而在糖果、糖和甜食组中，大部分食物被取代。核桃补充剂可导致营养和食物摄入模式的有利改变，从而有助于预防慢性疾病。营养素和食物的替代可能是解释核桃摄入与改善饮食之间有利关联的机制。
