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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 your senior dog losing weight? Our West Chester vets address these and other questions in this post. 

Is your old dog losing weight?

If you've noticed your older dog losing weight, this may occur gradually until you notice subtle differences in their body shape. They may also drop weight suddenly. No matter the speed of your senior canine companion's weight loss, it's important to understand why it's happening. 

This is because a dog's sudden weight loss can indicate an underlying health issue that may be serious. 

Where your dog's health is concerned, early detection is critical to effectively managing illness or disease and ensuring your older dog maintains the best quality of life possible in their golden years. 

You're in a great position to notice any changes in your dog since you see them every day. Even if they seem small or insignificant at the time, they may be a clue to a larger issue. As your dog ages, it's particularly important to watch for any subtle or more noticeable shifts in weight or appetite. 

In this post, we'll discuss when to be concerned about your dog's weight loss, some common causes of weight loss, why a dog may lose weight even if he is eating, what to feed an old dog that's losing weight, and finally, how to get your senior dog to gain weight. 

When to Be Concerned

While there's no need to assume the worst if your old dog is losing weight and muscle mass, most vets will tell you that if your dog has lost 10% or more of his or her normal weight it's time to identify what may be causing the pounds to drop. 

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

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

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 begin to lose weight as they get older and become very old. 

This may overlap with other signs that your senior dog is having difficulty maintaining peak health. 

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

Also, keep in mind that it's not unusual for even healthy senior dogs to gradually lose weight as they age. There may be a few specific causes for this type of weight loss, including:

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

It's also important to point out that more serious medical conditions can cause weight loss, though gradual weight loss is less likely to be triggered by a serious health problem. 

Weight loss in older dogs may be symptomatic of several other conditions. Changes in other behaviors or bodily functions can help your vet diagnose the issue. Other potential causes of weight loss include:

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

If your dog seems to be losing weight, we recommend contacting your West Chester vet as soon as possible to schedule a full physical exam.

Even if your senior dog has been losing weight slowly or gradually, but especially if this has been happening at a faster pace or if you've noticed other symptoms, it's imperative to visit your veterinarian right away to rule out potential illness or disease, even if your senior dog has been losing weight slowly or gradually. Your veterinarian can also create a customized diet plan geared to your dog's specific needs. 

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

You may be confused if your older dog is losing weight but is still eating well. In addition to the causes listed above, reasons for this 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 the ingredients in their food and the number of calories per serving) 
  • Liver disease
  • Maldigestion disorders such as exocrine pancreatic insufficiency, which 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 Old 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. 

Other Tips to Help Your Senior Dog Gain Weight

Along with having any underlying health issues diagnosed and potentially implementing a new diet plan for your dog, there are some other actions you can take that may help your dog gain weight. These include:

1. Change Your Dog's Feeding Schedule 

While dogs and people process and metabolize food slightly differently, there are some similarities in how we do so. People who eat within a few hours before heading to bed are more likely to gain weight, for example. This is because eating right before bed encourages your body to store nutrients as fat. Working with this knowledge, you can help your dog gain weight.

When you and your vet discuss your dog's diet, you might consider asking whether you should give your dog a smaller portion of food in the morning and a more significant amount in the evening before bedtime. This will help his body store fat when sleeping versus burning it off. 

Another tactic is to feed your dog smaller meals more frequently to help him digest nutrients throughout the day. Try to wait at least 30 minutes after a meal before exercising your dog, so he won't burn off the calories right away. 

2. Give Your Dog More Exercise 

While most people associate exercise with weight loss, remember that the goal is to help your dog add muscle mass to his body. Regularly exercising your dog is the best way to help him maintain a healthy weight. Coupled with a diet high in protein and fat, this should help him gain muscle and weight. 

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 that your dog's weight has changed significantly? Contact our West Chester vets to book a wellness exam for your senior dog.

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