CICO works quite well at the extremes. It's effectiveness varies, but it is directionally correct.
If someone is sitting at a 35+ BMI, then their caloric intake is so out of whack, that CICO helps ground them. Similarly, an anorexic who starves gets a clear directive for increasing weight by increasing calories.
CICO also promotes calorie general calorie comparison. It helps you understand that a milkshake has the same weight impact as an average Mediterranean lunch bowl.
Now the absolute impact on both foods will vary from person to person. But comparatively, it helps ground the unhealthiness of foods like sugar rich shakes and icecream.
The key insight from leptin is that the carbohydrates in the milkshake actually causes weight gain, not the calories. Yes, you do need to know how many calories your specific body needs to properly operate. For example, taller people require more calories than shorter people. However, obesity is a hormonal issue stemming from leptin resistance, not a caloric intake issue.
If someone is sitting at a 35+ BMI, then their caloric intake is so out of whack, that CICO helps ground them. Similarly, an anorexic who starves gets a clear directive for increasing weight by increasing calories.
CICO also promotes calorie general calorie comparison. It helps you understand that a milkshake has the same weight impact as an average Mediterranean lunch bowl.
Now the absolute impact on both foods will vary from person to person. But comparatively, it helps ground the unhealthiness of foods like sugar rich shakes and icecream.