Lumen is the world’s first handheld device that lets you measure your metabolism in real time — using just your breath. With instant insights into whether you’re burning carbs or fat, Lumen helps you make smarter nutrition, fitness, and fasting decisions. Whether you're aiming to lose weight, boost energy, improve performance, or support hormone balance, Lumen acts as your personal metabolic health coach, offering tailored nutrition plans and expert coaching to reach your goals faster. Scientifically validated and built for everyday life, Lumen transforms how you understand and work with your body.