An abundance of vitamin C in the diet may help lower a person's risk of developing type 2 diabetes, new research suggests.
In a study of middle-aged and older men and women, those with the highest blood levels of vitamin C were significantly less likely to develop diabetes over 12 years than those with the lowest levels, researchers found.

Fruits and vegetables are the main source of vitamin C in Western diets, and blood levels of vitamin C are good markers of fruit and vegetable intake, Dr. Nita G. Forouhi, at the Institute of Metabolic Science at Addenbrooke's Hospital, Cambridge, England, and colleagues note.

The current findings "re-endorse the public health message of the beneficial effect of increasing total fruit and vegetable intake," the investigators wrote in Archives of Internal Medicine.

Forouhi's team followed 21,831 healthy men and women who were 40 to 75 years old for the development of type 2 diabetes. At study entry, all participants provided detailed health and lifestyle information, as well as blood samples, which investigators used to determine vitamin C levels.

Over the course of the study, 423 men and 312 women developed type 2 diabetes, an overall rate of 3.2 percent.

According to the investigators, the likelihood of developing diabetes was 62 percent lower in men and women with the highest circulating vitamin C levels, relative to men and women with the lowest vitamin C levels.

Factoring out other characteristics associated with diabetes risk, such as older age, gender, family history, alcohol intake, physical activity, smoking status and body weight did not significantly alter these associations.

These data offer "persuasive evidence of a beneficial effect of vitamin C and fruit and vegetable intake on diabetes risk," Forouhi and colleagues conclude.

新的研究表明，饮食中丰富的维生素 C 可能有助于降低一个人患 2 型糖尿病的风险。

在一项对中年及老年男子和妇女的研究中，研究人员发现，过去 12 年里，那些在血液中具有最高维生素 C 水平的人比那些具有最低水平的人显著地不太可能患糖尿病。

英格兰剑桥 Addenbrooke 医院代谢科学研究所的 Nita G. Forouhi 博士和他的同事们注意到，水果和蔬菜是西方饮食中维生素 C 的主要来源，而血液中维生素 C 的水平正好是水果和蔬菜摄入量的标志。

目前的调查结果“重新支持增加水果和蔬菜的总摄入量对公共健康有有益作用的信息，”在内科医学文献中的这份调查写道。

Forouhi 的团队对 21,831 个 40 至 75 岁的健康男人和女人患 2 型糖尿病的情况进行了跟踪。在进入研究的时候，所有的参与者都提供了详细的健康状况和生活方式信息，以及由调查者用来确定维生素 C 水平的血液样本。
 
在研究过程中，423 名男子和 312 名妇女患了 2 型糖尿病，总体比例为百分之 3.2。

据调查者说，具有最高循环维生素 C 水平的男性和女性，相对于具有最低维生素 C 水平的男性和女性，患糖尿病的可能性要低 62％。

理出其它与糖尿病风险相关的特征，如老年人的年龄、性别、家族病史、饮酒、体力活动、吸烟状况和体重等，都没有显着改变这些关联。

这些数据提供了“有说服力的证据，说明维生素 C 以及水果和蔬菜的摄入，对于防止糖尿病的风险来说，是有有利作用的，” Forouhi 博士和他的同事们总结说。