Both devices that study heart disease help improve diets.
Lumen and FoodMarble They are polymers like "breathalyzers".
Both appeared CES 2019, the United States's biggest show of technology, and was held in Las Vegas from 8 to 11 January.
Devices work through smartphone applications to help their users digest food or calorie intake.
But, according to experts, these technologies have not yet been validated by the scientific community.
How many carbohydrates or fat contains?
Lumen's creator created nearly $ 2 million crowdfunding Indiegogo artifact manufacture.
The product is inhaler It breathes the carbon dioxide level.
This information allows you to control metabolism or chemical processes, amongst other things, to convert food into energy.
"(With Lumen), you do not have to have enough sugar in that chicken, or how many calories you burn in this race," said Dumen Cedar, creator of Lumen.
Instead, the BBC said, App shows What is? The user is burning: yes They are carbohydrates or fats.
Then, they suggest recipes that help fat fuel, and over time, Lumen is the best diet for each individual.
The device tested hundreds of users in the U.S. by Cedar.
However, research on product efficacy has not yet been studied by researchers in this field.
Lumen will be available for US $ 299 over the next few months, and its application will be free for the first year.
On the other hand, FoodMarble measures hydrogen levels for those who use digestive health.
The device was launched in December and the company saved 1,000 million dollars.
FoodMarble founder Lisa Ruttledge has told BBC that her breath's hydrogen level could mean a friend may have trouble digesting last meal.
"This happens in fermentation du intestines and exhale a bit of hydrogen generated in this process "he explained.
As food indicates hydrogen, the idea is that FoodMarble can induce inflammation, stomach ache and other gastrointestinal symptoms to improve the diet.
However, although physicians and nutritionists use these devices, they are more likely to question the accuracy.
"Only scientific research is limited and it proves what foods are sensitive to in hospital hospitals," said Kevin Whelan, dietary professor at King's College in London.
Because this happens Many factors may cause breathing, including the required time digest lunch, that's not always du myselfor.
Lisa Ruttledge said one of her company's goals is that FoodMarble needs to evaluate the first scientific research.
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