See how your daily calorie surplus transforms your body over 1, 5, 10, and 20 years. Uses NIH-style dynamic model with metabolic adaptation.
Your extra slice of pizza today = real kg in 10 years. This calculator uses NIH Body Weight Planner's dynamic model (not the refuted 7,700 kcal/kg rule) to show realistic long-term weight change with metabolic adaptation. Input your stats (age, weight, height, activity level) and either set a daily surplus (+/- kcal) or tap food presets (extra cookie, soda, pizza slice, fast food burger). See an animated weight trajectory chart colored by BMI zones, milestones at 1/5/10/20 years, pant size projections, exercise offsets needed (walking/running/cycling/swimming minutes to neutralize), and health risk warnings at each stage. Supports metric and imperial units.
The old "7,700 kcal = 1 kg" rule was refuted by a 2012 joint ASN/ILSI consensus. In reality, as you gain weight, your BMR rises ~20-25 kcal/kg, which shrinks the surplus over time. Weight asymptotes — plateaus after 3-5 years rather than growing linearly.
Very accurate for long-term projections. It uses the same principles as the NIH Body Weight Planner (developed by Kevin Hall), the gold-standard research tool. Real results vary due to metabolic differences, but the trajectory is scientifically sound.
US adults gain about 4.2 kg over 10 years (0.5 kg/year). Women gain roughly twice as much as men. 51% of annual gain happens during the 6-week holiday period (NEJM study).
Yes — just enter a negative surplus (deficit). However, note that metabolic adaptation makes weight loss slower than linear projections suggest. Biggest Loser contestants' metabolisms stayed 500 kcal/day lower even 6 years later.
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