Your puppy is changing in so many ways. In fact, the most rapid growth will take place in these first months of his life. His immune system is developing. Bones are growing. Muscles are getting stronger. All of this requires a nutrient-dense diet, formulated to support a medium-breed puppy's rate of development. To make sure your puppy is getting optimal nutrition to protect and maintain health and well-being, here are some key points to keep in mind.
From the time your puppy is weaned until 4 months of age, you should feed your puppy two to three meals a day, with the daily amount based on the guidelines of the food label. After 4 months of age, he should be fed twice a day on a regular schedule. Always have fresh water available.
Research shows that puppies need up to twice as much energy as adult dogs. Dramatic growth at this stage means your puppy requires an energy-rich, nutrient-dense complete and balanced diet. Puppies also require more protein than adult dogs. High-quality animal-based protein will help your puppy create new body tissue.
Not all puppies have the same nutritional needs. Medium-breed puppies actually have slightly higher metabolism rates per pound than large-breed puppies. And your puppy will reach his mature adult weight at about 12 months, sooner than larger breeds that reach adulthood as late as 24 months. Your puppy needs protein, fat, calcium, and phosphorus to support growth and development of bones, muscles, and other tissues. So giving him a food that supports his medium size is the easiest way to help make sure he's getting the right balance of nutrients for his metabolism and growth rate.
Remember, puppies have small stomachs. Make sure his food is nutrient-dense so he'll get a complete and balanced diet even though his stomach can only handle what seems like a small volume of food.
Aside from energy and protein, there are other important nutrients and ingredients vital to your puppy's diet:
These are important building blocks of nutrition. Look for them when you choose dry or canned dog food and when you select treats.
A medium-breed puppy reaches adult weight by about 12 months. You can begin feeding an adult dog food at this time, such as IAMS™ ProActive Health™ Adult MiniChunks. Your dog might not welcome the change at first, but don't worry. You can help ease the transition by gradually introducing the adult food. Try mixing 25% of the new food with 75% of his puppy food, then gradually change the proportions over the next three days until he's eating 100% adult food.

Your puppy’s nutritional needs will change as he grows into adulthood, but how do you know when your puppy is ready for adult food?
Depending on his breed size, at some point between 12 and 24 months of age, you should reexamine your puppy's nutritional needs and choose the right adult formula. His adult food could depend upon his metabolism (Does he gain weight easily?) and his activity level (Is it low, normal, or high?) These factors can help you find the ideal food for your dog.
The transition to a premium adult formula should begin when your dog approaches adult height and weight. The kind of dog you have will determine the right time to switch. When you do switch to adult formula, follow the same four-day process as you did when introducing your puppy to premium puppy food.
Small-breed dogs tend to mature physically much sooner than large-breed dogs. Follow these guidelines to help you decide when to switch formulas:
As your new puppy quickly matures into adulthood, he needs nutrition appropriate for his 'new' body. That means a high-quality, premium adult formula. Most veterinarians agree that feeding a complete and balanced premium food, such as IAMS™ ProActive Health™ Adult MiniChunks, throughout your dog's adulthood can promote a long and healthy life.