Scientists at the University of Wisconsin-Madison have developed a simple way of testing the air we breathe out to see whether we might be in the early stages of a number of diseases.
Illnesses including cancer, diabetes and infections change our metabolism in different ways. This research, published in the journal Metabolism, shows that it’s possible to detect these biochemical changes very early on in the development of a disease, perhaps within a few hours. This could mean that in future we could start treatment very much earlier.
“With this methodology we have advanced methods for tracing metabolic pathways that are perturbed in disease,” says senior author Fariba Assadi-Porter from the Nuclear Magnetic Resonance Facility at Madison. “It’s a cheaper, faster and more sensitive method of diagnosis.”
At the moment research is still in its early stages. The scientists have been studying mice that have metabolic symptoms similar to those found in women with polycystic ovary syndrome, a condition that may take a range of tests and examinations to diagnose.
“The goal is to find a better way of diagnosing these women early on, before puberty, when the disease can be controlled by medication or exercise and diet, and to prevent these women from getting metabolic syndromes like diabetes, obesity and associated problems like heart disease,” Assadi-Porter says.
The results showed that changes in the ratio of different elements in the animals’ breath could be detected almost instantly. This is important because the pattern of these ratios in blood or breath is different for different diseases – for example cancer, diabetes, or obesity – which means that this method could be used to detect a wide range of diseases,
Our bodies use different sources to provide us with energy, depending on our condition. “Your body changes its fuel source. When we’re healthy we use the food that we eat,” says Assadi-Porter. “When we get sick, the immune system takes over the body and starts tearing apart proteins to make antibodies and use them as an energy source.”
In other words, when we’re not well our bodies use proteins to keep us running instead of sugars. And this means that our bodies use different biochemical pathways. The end result is that what we breathe out is different when we’re ill.
Making it easier to detect illness earlier could make a big difference to our health. As Diabetes UK points out, the earlier this condition is diagnosed, the better. However, half the people with Type 2 diabetes are already showing signs of complications by the time they find out they have it. Complications may begin five to six years before diagnosis, and the diabetes may have begun 10 years or more before it is finally diagnosed.
Perhaps one day we’ll be able to pick up a metabolic breathalyser along with our toothpaste, but that is still some way off. The scientists who carried out this research have set up a company to develop the technology. As well as aiding diagnosis, they feel that it could tell us very quickly how effective a treatment is.
This isn’t the first research of this kind. Last year a study published in the British Journal of Cancer talked about an ‘electronic nose’ that could tell the difference between the molecules in the breath of people with head and neck cancer and that of healthy people. In 2010 early results from another study, carried out with people with lung, breast, bowel and prostate cancers also showed promising results.
There have even been small studies looking at whether dogs can tell the difference between the breath or urine of healthy people and those with cancer. The results were mostly positive, but a lot more research needs to be carried out before man’s best friend earns a white coat and a stethoscope.