You will lose weight if:

Weight loss fundamentally occurs when there is a negative energy balance, meaning that the amount of energy expended is greater than the amount of energy consumed. When your energy expenditure exceeds the calories you consume, your body begins to utilize stored energy for fuel, which leads to weight loss. This can occur through a combination of increased physical activity and/or reduced calorie intake, resulting in the body drawing upon its fat reserves to meet its energy needs.

In contrast, consuming less fiber or only eating when hungry does not necessarily guarantee weight loss, as these behaviors may not inherently affect overall caloric intake or energy expenditure. Additionally, if the calories consumed exceed energy expenditure, weight gain is likely to occur, not weight loss.