You've heard that a calorie is a calorie. The science says it's more nuanced than that. 500 calories of protein, 500 calories of carbohydrate, and 500 calories of fat have very different effects on your body — on hormone levels, satiety, muscle retention, and metabolic rate. Macro tracking is how you move beyond just counting calories into understanding what your food is actually doing.
What Each Macro Does
A brief, practical summary of the three macronutrients:
- Protein (4 kcal/g): The building material for muscle, enzymes, and immune function. Protein has the highest thermic effect — your body burns roughly 25-30% of protein calories just digesting them. It's also the most satiating macro per calorie.
- Carbohydrates (4 kcal/g): The body's preferred fast-fuel source, especially for the brain and during intense exercise. Quality matters enormously — whole food carbs with fibre behave very differently metabolically than refined carbs.
- Fat (9 kcal/g): Essential for hormone production, fat-soluble vitamin absorption (A, D, E, K), and cell membrane integrity. Fat is calorie-dense but not the dietary villain it was once thought to be.
EatCal's AI identifies not just total calories but the macro breakdown from your food photo — protein, carbs, and fat grams — along with fibre content and key micronutrients when detectable. This happens in under three seconds with a single photo.
How to Set Macro Targets
There is no universally correct macro ratio — it depends on your goal:
- Muscle building: Prioritise protein at 1.6–2.2g per kg of body weight; fill remaining calories with carbs and fat
- Fat loss: Higher protein (to preserve muscle in a deficit), moderate fat, lower carbs — though the exact split matters less than total calories and protein
- Endurance performance: Higher carb ratios (50–60% of calories) to fuel glycogen stores
Why a Photo Beats a Food Diary
Manual food logging consistently underestimates intake by 20–40% in studies — people forget portions, skip condiments, and find the friction of manual entry discouraging. A photo is accurate to what's on the plate. EatCal's AI has been trained on thousands of food images and uses portion estimation from visual cues (plate size, stacking, thickness) to calculate realistic quantities. You eat, you snap, you track.
Snap a photo of your meal — get calories and macros in seconds.
Download on App StoreMobilApps.tech · iOS Developer: Evren Haznedaroglu