Table scraps, occasional extras, and a complete diet are different
A small amount of safe human food used as a treat is not the same as feeding an improvised homemade diet as the dog's primary nutrition. Treats and extras should remain a minority of daily calories so they do not dilute a complete diet.
Why common recipes fall short
Published evaluations of home-prepared dog recipes have repeatedly found deficiencies in calcium, trace minerals, vitamins, essential fatty acids, and other nutrients. Meat-heavy recipes are particularly prone to an inappropriate calcium-to-phosphorus balance.
Who should formulate the diet?
For long-term home cooking, ask your veterinarian for referral to a board-certified veterinary nutritionist. The recipe may require a specific vitamin-mineral supplement and exact ingredient weights. Substituting ingredients casually can change the nutrient profile.
Puppies need extra caution
Growth diets have narrow requirements for energy, calcium, phosphorus, and other nutrients. Nutritional imbalance during growth can cause permanent skeletal problems, especially in large-breed puppies.
Avoid toxic ingredients
Onions, garlic, grapes, raisins, xylitol, chocolate, alcohol, and other toxic foods must stay out of homemade recipes. Raw diets also carry microbial and nutritional risks that should be discussed explicitly.