Lumen has been shown to accurately reflect the gold standard in measuring metabolic fuel, and it has also been shown to reflect real-time changes in metabolism. Here’s a summary:
“A pre-market, controlled, pilot study device was conducted to assess the body’s metabolic fuel utilization under different states, when compared to the gold standard, RER method. The Lumen technology was found to highly correlate with RER (R=0.83, p=0.003)2, in addition to effectively differentiating between fasting and post-carbohydrate consumption states (p=0.001)“
In the study with a major US university, Lumen compared the estimation of changes in metabolic fuel following different diets and high carb meals known to cause metabolic changes. Lumen measurements were taken after 12 hours of fasting when participants were on a a specific high carb then low carb diet, as well as 90 minutes after consuming high carb meals.
The study found that the Lumen device effectively differentiates between different metabolic states in response to low and high carb diet as well as in response to high carb meals, meaning that Lumen does accurately track changes in your metabolism both in real-time, and over extended periods of time.