Transparent science. Every calculation explained.
Metriqon doesn't use black-box AI to guess your metabolism. Instead, we use deterministic physiological models based on decades of clinical nutrition research. Every number we calculate comes from peer-reviewed equations that have been validated across thousands of people.
The core metabolic calculations are 100% based on established scientific equations. AI plays a very specific role: it helps us explain your results in plain language. The numbers themselves are never generated by AI—they're derived from proven physiological principles.
This approach gives you two things that matter. First, accuracy: you're not guessing based on some algorithm's hidden logic. Second, transparency: we can show you exactly how your numbers were calculated and why they matter for your health.
Your Basal Metabolic Rate is the number of calories your body burns at complete rest—just to keep your heart beating, your brain thinking, and your cells functioning. It's the metabolic floor. Even if you did nothing but lie in bed, your body would burn calories at your BMR.
Metriqon uses the Mifflin-St Jeor equation, which is the gold standard in nutrition science. It's accurate, widely validated, and used by hospitals and research institutions worldwide. It accounts for your weight, height, age, and sex.
If you weigh 75 kg, are 180 cm tall, and 35 years old, your BMR tells you how many calories you'd burn doing absolutely nothing. This is the foundation for everything else we calculate—your activity level is layered on top of this baseline.
While BMR tells you what you burn at rest, your Total Daily Energy Expenditure accounts for movement. TDEE is the total number of calories you actually burn in a day—the figure that matters for weight management.
Calculating TDEE is straightforward: we multiply your BMR by an activity factor based on how much you move.
Your activity level fits into one of four categories. Sedentary means mostly sitting with little exercise (1.2x multiplier). Lightly Active means light exercise or a job that keeps you on your feet (1.375x). Moderately Active is regular workouts most days (1.55x). Very Active is intense training or a physically demanding job (1.725x).
For example, if your BMR is 1,600 calories and you're moderately active, your TDEE is around 2,480 calories. That's what you'd burn on an average day. Eat more than that, and you gain weight. Eat less, and you lose weight. It's not mysterious—it's math based on how your body actually works.
This is where things get interesting. When you lose weight, your metabolism doesn't just scale linearly. Your body becomes more efficient at lower weights—which is why "eating less and less" eventually hits a wall where weight loss stalls.
Metabolic adaptation follows an allometric principle: as your weight drops, your metabolism slows disproportionately. We model this with a 0.75 power exponent—a finding from decades of clinical research on energy metabolism.
If you started at 90 kg and you're now at 75 kg, your BMR isn't just proportionally lower. It's lower by the 0.75 power of that ratio. This explains a real biological fact: after several months of dieting, your metabolism adapts and becomes more efficient, making further weight loss harder.
Understanding this helps you set realistic expectations. It's not that you're "doing something wrong"—it's that your body is physiologically adapting to preserve itself. This is why increasing protein and preserving lean muscle becomes critical as you lose weight.
Lean mass risk is a score from 0 to 100 that tells you how likely you are to lose muscle during your weight loss. It's calculated from four factors: how aggressive your calorie deficit is, whether you're getting enough protein, your age, and how quickly you're losing weight.
The deficit ratio measures how far below maintenance you're eating. The protein deficit ratio tracks whether you're hitting your protein target. The age factor accounts for the fact that older adults are more prone to muscle loss. The rapid weight loss factor penalizes very fast weight loss, which is associated with greater lean mass loss.
These factors are weighted because they don't all matter equally. Your calorie deficit is the biggest driver of lean mass risk, followed by protein intake. Age and weight loss speed matter, but less so.
You're in a sustainable deficit with adequate protein. Lean mass should be well-preserved.
You're at some risk of muscle loss. Focus on hitting your protein target and controlled deficit.
Significant muscle loss is likely. Prioritize strength training and raise protein intake immediately.
Your risk score is meant to guide, not alarm. A high score doesn't mean you'll definitely lose muscle—it means you need to be more intentional about preserving it through strength training and adequate protein.
Protein is non-negotiable for lean mass preservation during weight loss. It's the raw material your body needs to maintain muscle, and it also keeps you feeling full longer. The science is clear: higher protein intake during a deficit protects muscle.
Our protein targets range from 1.6 to 2.2 grams per kilogram of bodyweight—a range supported by extensive research. The exact target depends on your lean mass risk score.
If you're 75 kg and your risk score is 45, your target is 120 grams of protein daily. If your risk score is 70, it jumps to 165 grams—nearly half your daily calories from protein—to maximize muscle retention in a deficit.
This isn't about eating "extra calories." Protein is one of your three macronutrients. When you increase protein, you're shifting calories from carbs or fat, not adding to your total intake.
GLP-1 receptor agonists (semaglutide, tirzepatide, and similar medications) have become widely used for weight loss. They work by suppressing appetite and improving blood sugar control. But they also come with unique metabolic challenges.
GLP-1 medications can accelerate lean mass loss if you're not careful. You lose appetite, which makes it easier to eat less—but easier to also eat too little protein. The medications also may have effects on muscle protein synthesis. This makes protein intake and strength training even more critical for users.
For GLP-1 users, we typically recommend erring toward the higher end of protein targets, and being more conservative with calorie deficits. The appetite suppression means you might naturally eat in a large deficit—but that doesn't mean you should. Your body still needs protein and resistance training to preserve muscle mass.
The clinical evidence shows that people on GLP-1 therapy can lose significant amounts of muscle if they don't prioritize strength training. This is one area where the medical literature is evolving rapidly, and working with your doctor and a registered dietitian is essential.
Metriqon provides educational metabolic intelligence based on established physiological science. It is not a medical device, and it is not intended to diagnose, treat, cure, or prevent any disease.
The calculations and recommendations provided by Metriqon are for informational and educational purposes only. They should not replace professional medical advice, particularly if you have any pre-existing health conditions, take medications, or are considering significant changes to your diet or exercise routine.
Always consult your doctor before making significant changes to your nutrition, exercise program, or medication. If you're considering GLP-1 therapy or any other medical intervention, discuss it with your healthcare provider and a registered dietitian.
For exercise programming, work with certified fitness professionals who can assess your individual capabilities and design safe, effective training.