While there's no shortage of breathalyzers capable of detecting if you’ve had one too many drinks, a prototype device developed by researchers at NTT DOCOMO Research Laboratories analyzes your breath to detect if your body is burning fat. Besides letting users know if that exercise regime is actually shedding some pounds, its creators say the portable sensor could be helpful for diabetics and those trying to lose weight manage their daily diet.
Rather than detecting exhaled fat particles, the device detects the levels of acetone on one’s breath. Although primarily produced in the blood when fat is broken down, acetone is also expelled through alveoli in the lungs and is therefore present in exhaled breath, making it a good indicator of when the body has begun to break down fat.
The device, which is 10 cm (4 in) long, weighs 125 g (4.4 oz) and is powered by two AA batteries, features a pressure sensor to detect when someone breathes into it, and two types of semiconductor-based gas sensors that are capable of detecting acetone concentrations of 0.2 to 50 parts-per-million. After detecting the exhaled breath, the device calculates the acetone concentration levels and transmits the results, either via cable or Bluetooth, to a smartphone within 10 seconds.
To test the device, the researchers enlisted 11 men and six women volunteers. All were healthy but had body mass indexes (BMIs) above the Japanese average. The volunteers were split into three groups with the first carrying on their normal routine without any calorie restrictions or exercise requirements.
The second group was required to perform 30 to 60 minutes of light exercise, such as jogging or fast walking, per day without any calorie restriction, while the third group had their daily calorie intake restricted while carrying out the same exercise routine as the second group.
Each day before breakfast for a period of 14 days, all volunteers measured their body weight, body fat percentage and breath acetone concentrations. In addition to using the prototype device to measure the acetone concentrations, a standard measuring instrument was used for comparison.
The results showed that the breath acetone concentrations remained constant for those in the first two groups who were not able to lose significant amounts of fat, while the volunteers in the third group showed a significant increase in their breath acetone concentrations and were able to lose “significant amounts of fat.”
“Because obesity increases the risk of lifestyle-related illnesses, enabling users to monitor the state of fat burning could play a pivotal role in daily diet management,” says Satoshi Hiyama, principal investigator of the study. “Current standard methods, however, are still not practically suitable for point-of-care instrumentation for diet-conscious people who wish to monitor their own fat metabolism at home or outside.”
“Considering that the effect of dieting could be estimated from changes in breath acetone concentrations, we’ve shown that our prototype is a practical and alternative checker that can be used in individual dieting programs," Hiyama added. “It is also known that when diabetes is out of control, patients have elevated levels of breath acetone. It is possible that our prototype could be used to assess how diabetic control is being managed at home.”
The team’s paper is published in the Journal of Breath Research.