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The brainchild of twin sisters Merav and Michal Mor, Lumen is a handheld, breathalyzer-like device that measures carbon dioxide levels in the breath – a do-it-yourself alternative to a technique that has long been used for metabolic testing in clinical settings. From there, it can determine whether the body is burning more fat or or carbs at a given time, then advise users accordingly on nutrition, exercise, and rest via the connected app as part of an overall wellness regimen. “It can help people change their behavior,” says Daniel Tal Mor, CEO of Lumen, which raised $62 million in funding at the end of 2022.

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