The Deficit vs Delta

Understand your calorie balance. Log food your way. The Deficit brings your calorie intake, energy expenditure and progress together in a clear daily overview, using Apple Health data from the apps and devices you already use. SEE THE BIG PICTURE • Follow your calorie balance across days and custom date ranges. • See intake, macros, resting and active energy, and exercise. • Set a goal and compare your estimated progress. Days with incomplete intake can be excluded from the balance calculation. AGENTIC FOOD TRACKING — OPTIONAL, EFFORTLESS Tell the AI agent what you eat and it logs the meal for you. Dictate foods and amounts, or photograph a nutrition label and say or type “Log 200 g of this food.” The agent reads the label, calculates the portion and adds it to your diary. When you do not know the portion, it can estimate it for you to review and adjust. • Log meals by typing, dictating or taking a photo on iPhone or iPad. • Log multiple meals at different times in one request. • Dictate food and review your diary directly on Apple Watch. • Ask follow-up questions in chat or start a live voice conversation. • Add a personal coaching goal for more relevant feedback. • Review and edit portions and nutrition values. • Reuse familiar foods from your food memory. • Keep your diary and conversation in sync across iPhone, iPad and Apple Watch. • Start dictation with Shortcuts or the Action Button on supported devices. KEEP YOUR EXISTING TRACKER Prefer another food app? Turn off food tracking and continue using The Deficit as your Apple Health calorie-balance overview. YOUR CHOICES Sign in with Apple keeps your account connected across devices. Onboarding explains OpenAI processing when you use AI features. Apple Health access and optional transcript sharing remain under your control in Settings. You can turn off food tracking and delete your account in the app. AI uses credits. New accounts receive welcome credits; additional packs are available as one-time in-app purchases. Purchased credits do not expire while your account exists. At zero credit, AI pauses; your existing data and manual features remain available. Internet access is required for AI and cloud synchronization. Nutrition values and projected weight changes are estimates. Check suggested foods and portions before relying on them. The Deficit is not a medical device and does not provide medical diagnosis or treatment.

Delta tracks your weight and calorie intake and calculates your real TDEE — not a formula estimate, your actual one. 10 days free. One payment for unlimited access. No subscription. Most apps give you a TDEE based on height, weight, age, and activity level. That number is a population average applied to you. It's a starting point, not a measurement. Delta starts there too, but transitions away from it as you log real data. By day 10 your estimate is derived entirely from what you actually eat and how your weight actually moves. The longer you log, the more accurate it gets. Log your weight each morning and your calorie intake each day. Delta averages the last 10 days to filter out noise from water retention and normal fluctuation. It combines your intake with observed weight change to estimate your true maintenance calories, then smooths that estimate over 28 days to avoid overreacting to short-term variance. The result is a daily calorie target adjusted for your goal — cut, maintain, or bulk — grounded in your data rather than population averages. Key features: Daily weight and calorie logging Adaptive TDEE that transitions from formula to fully empirical as you log 28-day smoothing for a stable, actionable number Goal-based calorie targets for cut, maintain, or bulk Apple Health integration — weight and TDEE baseline written automatically Daily reminders for weigh-in and calorie logging Why Delta? Δ is the symbol for change. Your weight change and calorie balance are what actually determine your TDEE. Delta measures both and gives you a number that reflects your reality, not someone else's average.