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Weight Loss In Older Dogs: When To Worry

What causes weight loss in older dogs? When should you be concerned about an old dog losing weight? Our San Diego vets answer these and other questions in this post. 

Is your old dog losing weight?

If your older dog is losing weight, it may happen gradually until you notice subtle differences in their body, or they may drop weight suddenly. No matter the pace of your senior four-legged friend's weight loss, it's important to pin down why it's occurring. 

This is because a dog's sudden weight loss may point down to an underlying health issue - and sometimes this problem can be serious. 

With any health problem, early detection is key to managing disease or illness and ensuring your older dog maintains the best quality of life possible in their golden years.

Since you see your furry companion every day, you're in a great position to notice any changes, even if they seem small or insignificant at the time. As your dog ages, it's especially important to watch for any subtle or more noticeable shifts in weight or appetite. 

In this post, we'll discuss some common causes of weight loss in dogs, when you should be concerned, how a dog could lose weight even if eating, what to feed an old dog that's losing weight, and finally, how to get your senior dog to gain weight. 

Causes of Weight Loss in Older Dogs

While some dogs gain weight as they enter their senior years (age 6-8 for larger dogs and 8-10 for smaller dogs), most start to lose weight as they get older and become very old. 

This may accompany other signs that your geriatric dog is having difficulty maintaining their body condition. 

As dogs enter very old age, they'll need more calories and easily digestible protein sources to help them maintain their muscle mass. 

That said, it's not unusual for even healthy senior dogs to gradually lose weight as they age. There may be a few causes for this kind of weight loss, including:

  • Reduced appetite 
  • Poor absorption or digestion of food 
  • Loss of muscle mass

It's also important to note that weight loss may point to a more serious medical condition. Gradual weight loss is less likely to have been caused by a serious health issue.

Weight loss in older dogs can be a symptom of several other conditions. Changes in other behaviors or bodily functions may help your vet make a diagnosis. Other potential causes of weight loss include:

  • Cancer
  • Dehydration 
  • Diabetes
  • Gallbladder or liver disease 
  • Heart disease
  • Dental issues 
  • Kidney disease 
  • Hip arthritis or lower back issues

If your dog appears to be losing weight, we recommend contacting your San Diego vet to book a full physical exam

If the weight loss has happened faster, and especially if you are seeing other symptoms, it's imperative to see your veterinarian as soon as possible to rule out potential disease or illness, even if your senior dog has been losing weight slowly or gradually.  Your veterinarian can also develop a diet plan customized to your dog's specific needs. 

When to Be Concerned

While there's no need to assume the worst, most veterinarians will tell you that if your dog has lost 10% or more of his or her normal weight that it's time to look into what could be causing the drop. 

If your dog has lost this much weight in the past few months (or within a year), it's important that your vet conduct a full physical checkup. Your vet should also examine your pup if he or she:

  • Is acting differently or out of character
  • Seems stressed or is whining, pacing or panting 
  • Is severely constipated or has a distended belly
  • Is lethargic, confused or depressed 
  • Stops eating completely 
  • Dry heaves, vomits or has diarrhea

Why is my old dog losing weight even though he is eating?

You may be confused to find that your older dog is losing weight but is still eating well. In addition to the causes listed above, reasons may vary and include:

  • Changes in diet - either the kind or type of food he or she is eating or the ingredients (for example, sometimes manufacturers change ingredients in their food and the number of calories per serving) 
  • Liver disease
  • Maldigestion disorders such as exocrine pancreatic insufficiency that disrupt the body's ability to break food down into nutrients 
  • Malabsorption disorders such as inflammatory bowel disease 
  • Diseases such as diabetes, which can cause loss of weight and muscle mass

What to Feed an Older Dog That is Losing Weight

Keep in mind that older dogs, particularly very old dogs, require a diet dense with calories so they won't need to consume as much to reach their caloric requirements. 

Animals with normally functioning kidneys will need high-quality, easily digestible protein sources. While a dog's diet should contain moderate fat content in their earlier senior years, as the dog ages into their geriatric years, adding high-quality fats to the mix can improve protein efficiency and increase the calorie content.

Plus, picky eaters may be more inclined to eat. Fiber can be used to alleviate constipation issues for aging dogs and help them feel satisfied and "full" while they consume fewer calories. That said, truly geriatric dogs will often need lower amounts of fiber, more easily digestible food and higher density in calories. 

Look for premium dog food and ask your vet how much exercise is appropriate for your dog's specific needs. 

If your old dog is losing weight and muscle mass, your vet may run blood glucose tests and a urinalysis to check whether your dog has diabetes.

Other symptoms of diabetes include excessive thirst and urination, increased appetite, cloudy eyes, and chronic or recurring urinary infections. After a diagnosis is confirmed, treatment will include a specialized diet and insulin shots. 

How can regular veterinary care help as senior dogs age?

Your understanding of your dog's current health status and new or ongoing medical conditions, along with any changes in health or behavior you may have noticed, will help inform your vet about potential causes for your pet's weight loss or other symptoms. 

Regularly visiting your veterinarian for routine exams will help establish benchmarks for their normal health and behavior, which can be helpful when they aren't feeling well or the status of their health changes as they age. 

Your vet can advise you about how often they recommend coming in for a checkup and may recommend increasing the frequency of visits as your dog ages. 

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Have you noticed significant weight changes in your dog? Contact our San Diego vets today to book a wellness exam for your senior dog. 

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Kearny Mesa Veterinary Center is accepting new patients! Our experienced vets are passionate about the health of San Diego companion animals. Get in touch today to book your pet's first appointment.

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