Identification

• Working dogs may be underweightImage by Flickr.com, courtesy of Andrey
  
  Underweight dogs have low body fat and muscle mass. Dogs that have been homeless or abandoned are often thin and undernourished. Dogs that are very athletic, like working sled dogs, and dogs with underlying medical conditions may also be underweight.
  
  

Misconceptions

• The obvious solution to treating an underweight dog may be to overfeed. Overfeeding an underweight dog can cause "refeeding syndrome," an overload of carbohydrates resulting in serious physical distress, even death.
  
  

Commercial Dog Food

• Meals for underweight dogs can be supplemented with a meat-based commercial "puppy" or "growth" formula food. Four small portions should replace the once- or twice-daily feedings. Commercial dog foods high in fats are excellent choices: Look for eggs, raw fat and fish oil to place high in the ingredient list.
  
  

Vitamin and Minerals

• Underweight dogs should be given a balanced, broad-spectrum supplement. Amino acids, especially glutamine, and omega-3 and -6 fatty-acid supplements are also beneficial.
  
  

Warning

• A dog's diet should be formulated to ensure beneficial ratios of proteins, carbohydrates, vitamins, minerals and other components. Caution should be taken when adding food items specifically for weight gain so that nutrients are not provided in harmful balances.
  
  

Expert Insight

• If you have concerns about your dog's weight, consult a veterinarian. Obesity is a epidemic in pet dogs. Most dogs weigh much more than is healthy. Underweight dogs often have underlying conditions that require veterinary treatment.