How we calculate nutrition targets and caloric needs

We believe users deserve clarity about how our health metrics are estimated. Below is an explanation of the formulas we use, along with sources you can review.

Your recommended daily caloric intake

We estimate your baseline calorie needs using a BMR (Basal Metabolic Rate) equation, then adjust upward to estimate your TDEE (Total Daily Energy Expenditure). If you provide your body measurements, we are able to estimate your body fat using the US Navy Method. This body fat estimate allows us to calculate BMR using the Katch–McArdle equation.^{3, 4}. If you do not provide those measurements, we instead calculate BMR using the Mifflin–St Jeor equation^{5, 6}, which uses age, sex, height, and weight. After calcuating BMR, we estimate TDEE (BMR + addditional daily energy use) by applying an activity multiplier based on the activity level you select in the app.

Your final calorie recommendation is your TDEE^{1, 2} adjusted for your selected diet goal. If you selected weight loss, we apply a calorie deficit from a healthy range corresponding to your chosen speed of weight loss. Additionally, we will never recommend a daily calorie intake less than your BMR for health reasons. If you selected muscle gain, we apply a calorie surplus for bulking and lean bulking. Lean bulking generally provides better results by building muscle more slowly with a smaller surplus, but takes longer to achieve your desired body weight.

Macro split

A commonly used macro starting point in nutrition planning is 40% carbohydrates, 30% fat, and 30% protein^{7, 8}. We use this as a baseline reference because it is a familiar, balanced template that many people find practical when starting to track macros. As calorie needs increase, keeping fat too low can make the total food volume required feel impractically large. Because fat provides about 9 calories per gram (compared with about 4 calories per gram for protein or carbohydrates), we increase the percentage of fat to help users reach higher calorie targets more comfortably while keeping protein consistent⁹.

Some diet types have specific macro breakdowns that override these general recommendations. We apply these diet specific recommendations based on your choice of diet type.

• For the keto diet we assign 30% protein, 20g of carbs, and the remainder as fat¹⁰.
• For the low carb diet we assign 30% protein, 25% carbs, and 45% fat¹¹.
• For the low fat diet we assign 30% protein, 25% fat, and 45% carbs¹².

Additionally, you can always override our calorie and macro recommendations with your own values in your user profile.

Additional Information

Body fat percentage estimation

To estimate body fat percentage we use the U.S. Navy Method¹³ which requires age, sex, height, and weight, plus body circumference measurements of your neck, waist and also hips for females. This approach is widely published in military body composition guidance and provides a practical estimate without requiring specialized equipment.

Protein targets

Protein needs are commonly discussed in grams per day based on body weight. A widely used baseline reference is 0.8 g of protein per kilogram of body weight per day (about 0.36 g/lb) as a general minimum target for adults, and you may also see higher ranges such as 1.0–1.2 g/kg per day discussed in expert guidance for supporting muscle maintenance in older adults¹⁴. We use these references as context, but these Recommended Daily Allowances (RDA) are designed to prevent deficiency and therefore may not be sufficient to provide optimal health¹⁵. It is common to see recommendations such as 1 g of protein or more per pound (about 2.2g/kg) of lean mass in guidelines recommended by fitness communities¹⁶.

In order to create a consistent, repeatable target across a wide range of body types and calorie needs, we assign protein using a fixed percentage of daily calories. Our recommendation of 30% protein aligns with the suggestion of 1g/lb of lean body mass for most people.

Sources