For training or weight loss New sensor records fat loss via breathing air

New sensor developed: Measure fat loss via the breathing air

Researchers from Switzerland have developed a sensor with which it is easy to measure by breath analysis when the body starts to burn fat. According to the scientists, the technique is "for everyday use, for training in a fitness center or during a diet."

Endurance sports help with weight loss

According to research, more and more obese people live in Germany. Many try to get rid of their fat stomach by avoiding certain foods or dieting. But that alone is usually not enough. In order to reduce belly fat, it is usually necessary to move regularly. Endurance sports are particularly well suited here. With a newly developed sensor, it will be easier in the future to measure by breath analysis when the body starts to burn fat.

Researchers have developed a sensor that can be used to measure fat loss via the respiratory air. The technique is suitable for sports or dieting. (Image: Company V / fotolia.com)

Fat loss easily detectable in the breath

Our body burns endurance training not only carbohydrates such as sugar, but also fats. When the body begins to burn fat can be determined today, for example, by analyzing biomarkers in the blood or urine.

Scientists at the Swiss Federal Institute of Technology (ETH) Zurich and the University Hospital Zurich (USZ) have now developed a method to detect fat loss easily and in real time in the breathing air of athletes.

"Fat loss in the body produces by-products that get into the blood," said Andreas Güntner, postdoc in the group of ETH Professor Sotiris Pratsinis, according to the "ETH News".

In pulmonary alveoli these molecules can pass into inhaled air, especially volatile among them. The most volatile of these fat loss products is acetone.

The Swiss researchers have developed a small gas sensor that measures this substance. Your sensor is much more sensitive than previous sensors: it can detect single acetone molecules in hundreds of millions of other molecules.

In addition, the sensor measures only acetone and nothing else; the other over 800 known volatile components in the air do not affect the measurement.

The experts report on their new development in the journal "Analytical Chemistry".

Function of the sensor checked by sports people

In collaboration with lung specialists at the University Hospital Zurich, the scientists tested the function of the sensor in sports volunteers. They completed one and a half hours of training on a stationary bike with two short breaks.

At regular intervals, the researchers had the subjects blow into a tube connected to the acetone sensor.

"We were able to show that the acetone emission in the air differs greatly from person to person," explained Güntner.

The former and now obsolete opinion was that sportspeople start to burn fat only after a certain period of exercise and heart rate.

In the measurements of the scientists used the fat burning in some subjects actually only towards the end of the one and a half hour training session. For other volunteers, the measurements showed that her body burns fat much earlier.

Control measurements showed that the new measurement method is in good agreement with the concentration of the biomarker beta-hydroxybutyrate in the blood of the study participants. This blood analysis is one of today's standard methods for tracking fat loss.

Chip was originally to be used for diabetes diagnosis

The sensor developed by the scientists is a chip coated with a porous film of special semiconducting nanoparticles. The particles consist of tungsten trioxide, which the researchers had mixed with individual silicon atoms.

The development of this chip started seven years ago. At that time, ETH Zurich researchers discovered that tungsten trioxide nanoparticles interact with acetone, provided that the atoms of the nanoparticles are arranged in a specific crystal structure.

The interaction reduces the electrical resistance of the nanoparticle-coated chip, which is measurable.

Originally, the idea was to use the chip to diagnose diabetes. In the respiratory air of patients with untreated type 1 diabetes, high concentrations of acetone can be detected.

However, scientists have now shown that the sensor is sensitive enough to detect the very low concentrations of acetone in the breath of athletes.

The researchers are in the process of refining the measurement technology so far that it should be possible with significantly smaller chips than those used in the study. They should fit into a handy device.

"This allows athletes and weight loss individuals to individually check when their body starts to burn fat, so as to optimize their training," said Güntner.

Technology for everyday use

Highly sensitive acetone measurements could already be made with other measuring devices - so-called mass spectrometers. However, these are large and very expensive laboratory equipment.

Researchers in the current study use this information to check their measurements. There are also portable devices for the acetone measurement in the breath. These can only be used once, however, and they only display the result after a few minutes.

"Our technology, on the other hand, has the great advantages of being cheap, handy and yet highly sensitive, as well as enabling real-time measurements," says Güntner. "It is therefore suitable for everyday use, for training in a fitness center or during a diet."

The scientists are now planning to develop their measuring method to market maturity. There is already a gauge prototype.

At the same time, scientists are working to develop gas sensors for other medically interesting molecules in the air, including those for ammonia, which can be used to check kidney function, isoprene to study cholesterol metabolism, and various aldehydes for early detection of lung cancer. (Ad)