Although the health benefits of diets rich in fresh fruit and vegetables are well-established, worldwide evidence on the potential effects of fruit consumption on the development and progression of diabetes is rather limited. Fruit is a rich source of potassium, dietary fibre, antioxidants, and various other potentially active compounds, and contains little sodium or fat and relatively few calories. But, although higher fruit consumption has been rather consistently and convincingly related to lower risk of cardiovascular diseases, its sweetness, i.e. high sugar (fructose) content, has led to concerns about its potential harm for people with diabetes, particularly in China and many other East Asian countries, where the prevalence of diabetes is rising rapidly.

The research was conducted on 0.5 million Chinese adults from ten diverse urban and rural areas across China (The China Kadoori Biobank).

Fresh fruit consumers have a lower risk of diabetes

About 94% of participants were free of diabetes at baseline and the other 6% had either previously diagnosed diabetes or were defined as diabetes during baseline survey. In the study, the proportion of participants who reported never or rarely consuming fresh fruit was about 3 times higher in individuals with previously diagnosed diabetes than in those without diabetes.

This indicates that the problem of fruit abstinence among diabetic patients was still quite common in China at 2004-2008 when the baseline survey was conducted. During 7-year follow-up, the study documented nearly 10,000 new onset cases of diabetes and, compared with non-consumers, daily fresh fruit consumers had a 12% lower risk of developing diabetes.

High fresh fruit consumption lowers overall mortality and diabetes-related complications

More importantly, about 11,000 cases of vascular diseases and 3400 deaths were recorded among those over 30,000 participants who had pre-existing diabetes already at the beginning of the study and higher fresh fruit consumption was also associated with lower risks of diabetes complications, with each 100g/ day higher fresh fruit consumption was associated with 17% lower overall mortality, 13% lower risk of developing diabetesrelated complications affecting large blood vessels (e.g. ischemic heart disease and stroke) and 28% lower risk of developing complications affecting small blood vessels (i.e. kidney diseases, eye diseases, and neuropathy).

“Fresh Fruit consumption should be recommended for all, including people with diabetes”1!

Although the observational nature of the study does not allow a conclusion on causality, it provided strong supporting evidence for recommending a higher level of fruit consumption in people living with diabetes. However, the findings should not be interpreted as people (including diabetes patients) could eat as much fresh fruit as possible or even the more the better. People, particularly those with diabetes, should always keep an eye on the amount of total calories (carbohydrates) they consume and their body weight. In fact, in the current study population, the average fresh fruit consumption among those daily consumers (the highest category) was about 150 grams per day, roughly equivalents to a normal sized apple. Furthermore, the study focused on fresh fruit only and Chinese people usually eat whole fresh fruit raw as snack. Therefore, the potential benefit of fresh fruit on primary and secondary prevention of diabetes should not be extended to other fruit products such as fruit juice and fruit puree which may contain very high amount of added sugar (e.g. sucrose) and/or little fibre. Due to the limitation of data, the study could not answer questions such as what are the best types of fresh fruit, the best timing of fruit consumption (before or after a meal), and the main underlying mechanisms involved. Future studies on such research questions are warranted.

Based on: Du H, Li L, Bennett D, Guo Y, Turnbull I,Yang L, et al. (2017) Fresh fruit consumption in relation to incident diabetes and diabetic vascular complications:
A 7-y prospective study of 0.5 million Chinese adults. PLoS Med 14(4):e1002279. https://doi.org/10.1371/journal.pmed.1002279