Do different foods affect your diabetes medication?

Monday, 30 April 2018

There are a lot of myths and rumours about certain foods and their effect on your medication or diabetes management. We take a look at three of the most commonly cited and give you our verdict.


Grapefruit contains (furanocoumarins), a natural compound that interacts with the enzyme pathway responsible for metabolising some medicines in the body (CYP3A4), resulting in more of the drug entering your bloodstream. Professor Krass, from the University of Sydney, says there is no known relationships between metformin and grapefruit. However if you are taking cholesterol-lowering statins there could be a reaction.

Verdict: To be safe, restrict drinking and eating grapefruit if you take statins until you talk to your doctor about the risk. Rest assured, sweet oranges and lemons don’t pose a risk. To learn if your particular medicine interacts with grapefruit juice, refer to the ‘Consumer Medicine Information’ leaflet or call the National Prescribing Service Medicines Line on 1300 633 424.

Bitter Melon

Bitter melon (Momordica charantia) is a fruit popular in Asia and Africa typically consumed as a vegetable in curries and stir-fries. The seeds, leaves and root have been used as a traditional diabetic remedy due to the natural compounds that behave like ‘plant insulin’. However, there is no evidence to support the use of bitter melon as a replacement for insulin injections. Research shows bitter melon can, in the short-term, lower high blood glucose levels after meals. But long-term clinical trials fail to show an improvement of HbA1c levels in adults living with type 2.

Verdict: As bitter melon mimics the action of insulin, if you also use insulin or a medication that stimulates insulin production, there is the risk of a hypo. It is also not deemed safe during pregnancy or breastfeeding as it can stimulate menstruation. If your diabetes is managed with diet alone, with no likelihood of pregnancy or breastfeeding, you may like to experiment with this unique and distinct tasting veg. Try incorporating it into your curry or stir-fry, as you would any other vegetable.


Cinnamon (Cinnamomum aromaticum, Cinnamomun cassia) is a sweet spice derived from bark and is commonly used in cooking and baking. Research has centred in on its role in potentially improving insulin sensitivity and cholesterol levels.

Although some clinical trials showed improvement in fasting blood glucose levels and lipid profiles with ½ teaspoon cinnamon daily, others trials failed to show improvement in these measures or HbA1c in people with type 1 and type 2 diabetes. Therefore, the consensus of the American Diabetes Association is that there is insufficient evidence to support the use of cinnamon for the treatment of diabetes.

This spice is considered safe to consume in amounts typically used in food, for example, half to three teaspoons. Some have warned that if used in greater amounts, it could pose a risk if you have liver disease.

Verdict: If you enjoy the taste of cinnamon, enjoy sprinkling it on your oats or bircher muesli, freshly made air-popped popcorn and your home-made baking.  But, if you are hoping this spice will be that magical ingredient to manage your diabetes, the jury is not convinced it is up to the task.

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