While fruit juices have a healthy reputation, I don’t believe their as healthy as their image suggests. Some of the issues I have with them are detailed here. One key property of fruit juices that causes me to advise their consumption with caution is the fact that they tend to be very sugary indeed. Many fruit juices have a sugar concentration similar to sugary soft drinks. And some juices (e.g. grape juice) contain considerably more sugar than this even. Now, if I had to drink fruit juice or a sugary soft drink I’d choose the former (the fruit juice wins hands down, I reckon, in terms of it ability to deliver some nourishment to the body). What I am saying, though, is that the intensely sugar nature of fruit juices make this far from an ideal beverage for those seeking to optimise their health.
With this in mind, I was interested to read the results of a recently-published study in which the relationship between the consumption of green vegetables, whole fruit and fruit juice and risk of diabetes was assessed in more than 73,000 women over a period of 18 years [1]. The results of this study showed that:
An increase in whole fruit consumption of 3 servings per day was associated with an 18 per cent reduced risk of diabetes.
An increase in green vegetable consumption of 1 serving a day was associated with a 9 per cent reduced risk of diabetes.
An increase in fruit juice consumption of one serving a day was associated with an 18 per cent INCREASED risk of diabetes.
Epidemiological studies of this nature may show that drinking fruit juice is associated with diabetes risk, but they cannot prove that fruit juices can cause diabetes. However, the high sugar nature of fruit juices means that they may indeed have a genuine diabetes-inducing effect. It is sometimes said that the fruit sugar (fructose) found in high levels in fruit juice is relatively harmless, on account of the fact that it does not tend to raise blood sugar levels. However, as I detail here, fructose is anything but safe, and its consumption has been found to induce something known as ‘insulin resistance’, which is a precursor of diabetes. Personally, I don’t think it’s any major surprise that the drinking of fruit juice has been implicated in the development of diabetes. My advice remains the same: give them a wide berth.
References:
1. Bazzano LA, et al. Intake of Fruit, Vegetables, and Fruit Juices and Risk of Diabetes in Women. Diabetes Care [epub 4 April 2008]
