Weight Loss Projection Calculator

Weight loss is rarely a linear process. While the standard rule of "3,500 calories equals one pound of fat" provides a baseline, it fails to account for metabolic adaptation - the body's survival mechanism that lowers energy expenditure as mass decreases. This forecasting tool uses a dynamic model to simulate the physiological slowdown that occurs during prolonged dieting, offering a more realistic timeline than simple linear calculators.

Successful long-term weight management requires understanding the relationship between the cumulative caloric deficit and time. This calculator projects the trajectory of weight reduction, highlighting potential "plateau" periods where the deficit narrows as the body shrinks. By visualizing the timeline, users can set sustainable expectations and adjust their strategies (such as diet breaks or refeeds) to mitigate metabolic downregulation.

The projection logic iterates daily, adjusting the Basal Metabolic Rate (BMR) as weight (W) decreases. The simplified adaptive model is:

This implies that for every 1% of body weight lost, the efficiency of the deficit decreases slightly due to hormonal changes (Leptin/Ghrelin), making the last few pounds harder to lose than the first.