Low-Carbohydrate Diet and Type 2 Diabetes Risk in Japanese Men and Women: The Japan Public Health Center-Based Prospective Study

ObjectiveEvidence is sparse and contradictory regarding the association between low-carbohydrate diet score and type 2 diabetes risk, and no prospective study examined the association among Asians, who consume greater amount of carbohydrate. We prospectively investigated the association of low-carbohydrate diet score with type 2 diabetes risk.MethodsParticipants were 27,799 men and 36,875 women aged 45–75 years who participated in the second survey of the Japan Public Health Center-Based Prospective Study and who had no history of diabetes. Dietary intake was ascertained by using a validated food-frequency questionnaire, and low-carbohydrate diet score was calculated from total carbohydrate, fat, and protein intake. The scores for high animal protein and fat or for high plant protein and fat were also calculated. Odds ratios of self-reported, physician-diagnosed type 2 diabetes over 5-year were estimated by using logistic regression.ResultsDuring the 5-year period, 1191 new cases of type 2 diabetes were self-reported. Low-carbohydrate diet score for high total protein and fat was significantly associated with a decreased risk of type 2 diabetes in women (P for trend DiscussionLow-carbohydrate diet was associated with decreased risk of type 2 diabetes in Japanese women and this association may be partly attributable to high intake of white rice. The association for animal-based and plant-based low-carbohydrate diet warrants further investigation.

研究目的：现有关于低碳水化合物饮食评分（low-carbohydrate diet score）与2型糖尿病（type 2 diabetes）风险之间关联的证据既稀缺又相互矛盾，且尚无前瞻性研究针对碳水化合物摄入量更高的亚洲人群探讨二者的关联。本研究前瞻性探究了低碳水化合物饮食评分与2型糖尿病风险的关联。研究方法：研究对象为参与日本公共卫生中心前瞻性研究（Japan Public Health Center-Based Prospective Study）第二次调查的27799名男性与36875名女性，年龄介于45至75岁，且无糖尿病病史。通过经过验证的食物频率问卷（food-frequency questionnaire）确定受试者的膳食摄入情况，并基于总碳水化合物、脂肪及蛋白质摄入量计算低碳水化合物饮食评分；同时也分别计算了高动物蛋白-脂肪与高植物蛋白-脂肪对应的饮食评分。采用logistic回归（logistic regression）模型估算5年随访期间自我报告的经医生确诊的2型糖尿病的比值比（odds ratios）。研究结果：在5年随访期间，共报告1191例新发2型糖尿病病例。在女性群体中，高总蛋白与脂肪摄入的低碳水化合物饮食评分与2型糖尿病风险降低显著相关（趋势检验P值）。讨论：低碳水化合物饮食与日本女性的2型糖尿病风险降低存在关联，该关联可能部分归因于白米的高摄入量。基于动物源性与植物源性的低碳水化合物饮食相关关联仍需开展进一步研究。