Dogs have been called man’s best friend, and most people really do love their dogs. However, well-meaning people often inadvertently do all kinds of things that shorten their beloved pet’s life.

Owning a dog is an enormous responsibility, but people frequently get caught up in new puppy love. They don’t think through the ramifications of dog-ownership and, many times, the dog is the one that pays the price.

According to Canada’s Pet Information Centre for Dogs, Cats, and Humans, the average life span of a dog in North America is over 12 years. When people take good care of their dogs, they can help them live longer, healthier, and happier lives. However, the reverse is true as well.

When people do not take proper care of their dogs, they can shorten the dog’s life span. Here are 15 ways that people unnecessarily shorten their dog’s life.

1. Improperly feeding the dog

Just like with people, a dog’s diet can dramatically influence his health. Dog owners should feed their dogs the very best food that they can afford. According to dog trainer Allison Allen, poor quality dog foods can cause skin irritations, an oily coat, runny eyes, sore ears, and overall poor health.

She recommends that people read labels to choose the best dog foods and choose foods that include “human grade” ingredients.

However, choosing dog foods that include human grade ingredients does not mean that owners should feed a dog anything and everything that the family eats. According to dog guru Cesar Millan, if one wants to give a dog a “people food” treat, the dog can be fed cheese, peanut butter, eggs, cooked chicken, or yogurt.

However, high-calorie, fatty human treats are not healthy for dogs at all. Regularly scraping leftovers into a dog’s dish can lead to obesity and digestive upsets that can dramatically shorten a dog’s life.

Cesar Millan also says that dog obesity can contribute to health problems that can severely impact his health. Hypothyroidism, heart disease, arthritis, certain cancers and diabetes are just a few of the health problems that are caused by overfeeding a dog.

Dog owners need to find ways other than food to reward dogs for good behavior, such as affection, verbal praise, and playing games. Owners should also keep an eye on the body condition of their dogs and tweak the feeding of the dog, if he begins to put on weight.

To tell if a dog is fat, owners should feel around the dog’s ribs and spine. The bones should be easily felt with just a small layer of fat padding the dog’s skeleton. However, if the owners cannot easily find the dog’s bones, the dog is overweight.

Overweight dogs will benefit from additional exercise and limiting food to two small meals per day. A veterinarian can tell dog owners how much food the dog should be consuming per day.