Calories not being reported correctly in Energy Summary (both web and mobile)

snowfall

This started happening aroung 3pm EST today (5/21/2025). To reproduce, go to an empty day, and add 1000g of "Broccoli, Cooked From Fresh" from the NCCDB. The total calories from protein + carbs + fat should be (23.8 * 4) + (38.8 * 4) + (4.1 * 9) = 287, but the Energy value displayed in cronometer is 350. The popup when hovering over the "Consumed" graphic indicates 58kcal from protein, 257kcal from carbs, and 34kcal from carbs. These numbers are all wrong.

snowfall

Here's what ChatGPT says about it -- I guess it's right?

Cronometer is not using the 4-4-9 rule exactly

It uses Atwater specific calorie values, which are derived from lab analysis. These values vary per food item, depending on:
• Digestibility
• Fiber type (some carbs aren’t fully digestible but still partially contribute energy)
• Food matrix complexity

Example:
• Cooked broccoli has a lot of fibrous carbohydrates, but some of that fiber is fermentable in the gut and can contribute calories (~2 cal/g).
• That might explain why Cronometer assigns 237 calories to 38.8g of net carbs — that’s ~6.1 cal/g, not 4.

2. Net Carbs in Cronometer may still include fermentable fiber

Even though it lists “Net Carbs”, it may be using non-zero energy values for some fiber types, like soluble or fermentable fiber, which contribute short-chain fatty acids after fermentation.

3. Protein may have lower usable energy in plant foods

Some proteins in plants are less digestible (e.g., from the cell walls, or anti-nutrients). So the actual usable energy might be closer to 2.4 cal/g, depending on the food. That could explain why 23.8g of protein is listed as only 58 cal instead of 95.

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🔚 Summary

Cronometer uses lab-based (Atwater specific) values rather than textbook macros × standard calorie formulas. That’s why you’ll sometimes see calorie totals that don’t add up “by the book.” This is normal in Cronometer and actually reflects more accurate food science.

If you’re just tracking macros for general goals, the 4-4-9 rule is fine. But for precise energy intake or detailed nutrition analysis, Cronometer’s method is actually more accurate.