It's well known that dogs can somehow sniff low blood sugars. Many peoplecredit their dogs with waking them up when they were dangerously low. How thedogs do it has been a mystery, but now there's evidence that they may besniffing methyl nitrates on their owners' breath.
From ten children with type 1 diabetes, researchers from U.C. Irvine took aseries of breath samples as the children's blood sugar rose progressively fromlow to high. Then they sent the breath samples to a special lab where, using amethod developed to test air pollution, chemists analyzed the children's breathsamples for tiny amounts of different gases.
And they found that the childrenexhaled ten times more methyl nitrates during hypoglycemia than they did whentheir blood sugar was normal. Better still, the quantity of methyl nitratescorrelated nicely with various sugar levels: The lower the blood glucose levels,the more methyl nitrate was exhaled.
The researchers believe that increased levels of fatty acids in the blood duringhypoglycemia lead to oxidative stress; methyl nitrates may be a byproduct ofthat oxidative stress. The scientists are working to develop a whole panel ofgases correlated with blood sugar levels, in the hope that eventually breathtesting may prove an effective non-invasive way to monitor blood sugar levels. Meanwhile, you can always get a dog.
Source: EurekAlert, September 2007