Pears Could Help You Manage Diabetes

People who have diabetes sometimes believe that they shouldn’t eat fruit because it contains too much sugar. But, while dried fruits such as raisins or dates and canned fruit in syrup can certainly send your blood sugar sky-high if you eat a lot of them, most fresh fruits have a low glycaemic load, meaning that they have little effect on blood sugar levels. More than that, fruit has several real health benefits that can help you to manage diabetes.

One way that fruit keeps us healthy is by keeping the body alkaline, counteracting the effects of acid-forming foods, as I explained in a previous post here. And of course, fruit contains plenty of fibre and is an excellent source of the mineral magnesium, both of which help to keep blood sugar in balance. Other important compounds in fruit are its polyphenols, which are the pigments that give fruit its colour. And while we usually think of berries (such as blueberries, blackberries, strawberries and raspberries) as being particularly high in polyphenols, another polyphenol-loaded fruit is the pear.

Scientists at North Dakota State University recently looked into how two varieties of pears could play a role in managing diabetes and associated hypertension (high blood pressure).¹Their results showed that pears could have multiple benefits for people with diabetes. One finding was that pear polyphenols strongly inhibit the action of the enzymes α-glucosidase and α-amylase, which are responsible for the digestion of dietary carbohydrates to glucose. This means that the carbohydrate content of pears is broken down to glucose only very slowly, so that it does not cause a spike in blood sugar levels. And when pears are eaten as part of a meal, they could also help to slow down the digestion of carbohydrates from other foods.

The varieties of pears used in this study were Bartlett and Starkrimson. You are unlikely to find the red-skinned Starkrimson pears in British supermarkets, but Bartlett is simply another name for the familiar and widely-available Williams pear. And while the skin of Starkrimson pears had the highest polyphenol content (not surprising given its bright red colour), the Bartlett/Williams variety turned out to have more of the anti-diabetic polyphenols in its flesh than the Starkrimson.

An extract from the flesh of Williams pears was also found to act in exactly the same way as ACE-inhibitor drugs (although less strongly), suggesting that these pears could have a gentle blood-pressure lowering action. Other studies have demonstrated that polyphenols in fruits really can help to lower blood pressure, as well as to improve cholesterol and blood fatprofiles, protect blood vessels from oxidative damage, improve pancreatic beta-cell function and stimulate insulin secretion.²

How to get the best from fruit

Choosing the best fruit to eat for general health and for anti-diabetes benefits is not difficult if you follow a few basic principles:

• Fruits that can be eaten freely, since they have the lowest glycaemic load (GL) values and the highest levels of polyphenols and antioxidants, include:

- Blueberries, blackberries, raspberries and strawberries
- Cherries, grapefruits, pears, melons and watermelons

• Apples, plums, peaches, apricots, oranges and kiwi fruit have intermediate GL values, so are also OK to include in a low-GL diet in moderate amounts

• The highest-GL fruits, to avoid or to eat only occasionally and in small amounts, are bananas, grapes, papayas, mangoes and pineapples

• Also steer clear of dried fruits such as raisins, sultanas, figs, dates, dried apricots and dried apple, which have high GL values

• Since beneficial polyphenols are often concentrated in the skin of fruit or just below it, wash fruit before eating but don’t peel it

• And, since you will be eating the skin, it makes sense to choose organically grown fruit whenever possible, to avoid taking in pesticide residues along with those beneficial polyphenols!

Scientific studies of this kind provide helpful information about ways in which diabetes can be treated without drugs. But there is nothing like a real-life success story to bring home the message that even advanced type 2 diabetes can be reversed using diet and lifestyle changes alone. In my next blog post I shall be telling you how a 63-year old man who was overweight, had type 2 diabetes and was in danger of having a leg amputated, got his life back and is now diabetes-free.