Life-Stage Nutrition
Kittens (under 12 months)
Kittens need substantially more protein, fat, and calories per kilogram of body weight than adults — growth is energy-expensive. Look for food labeled for "growth" or "all life stages" (AAFCO's growth profile is more demanding than its adult maintenance profile, so an all-life-stages food covers a kitten's needs). Kittens are typically weaned onto solid food by 8-10 weeks and can move to an adult formula around 12 months for most breeds (some large breeds mature later).
Adults (1-7 years, varies by breed)
Once growth stops, calorie needs drop — continuing to feed a kitten-level diet is a common cause of adult weight gain. Neutering also lowers energy requirements by roughly 20-30%, which is worth remembering right around the time most cats are neutered as young adults.
Seniors (roughly 11+ years)
Older cats often need fewer calories due to reduced activity, but some very senior cats (15+) actually need more due to reduced ability to digest and absorb nutrients efficiently — weight loss in a senior cat is worth a vet visit, not just a diet change, since it can also signal illness (hyperthyroidism, kidney disease, and diabetes are all more common in older cats and can cause weight loss despite normal or increased appetite).
Pregnant & Lactating
Energy needs rise substantially — pregnant cats need roughly 1.6-2x maintenance calories by late pregnancy, and lactating queens can need 2-3x or more depending on litter size. A kitten-formula or all-life-stages food is commonly recommended through pregnancy and nursing, since its higher calorie and protein density matches the increased demand.