What Causes Fatty Lipomas in Dogs?

If you’ve ever noticed a soft, squishy lump under your dog’s skin, there’s a good chance it could be a lipoma—a benign (non-cancerous) fatty tumor. While they’re usually harmless and common in middle-aged to senior dogs, they can still be a cause for concern for pet parents. So, what exactly causes fatty lipomas in dogs?

What Is a Lipoma?

A lipoma is a slow-growing mass of fat cells, usually found just under the skin. They’re most often found on the chest, belly, thighs, or upper legs. Most lipomas are painless and don’t cause health issues unless they grow large enough to interfere with movement or are located near vital organs (in rare cases).



What Causes Lipomas?

1. Age

Lipomas are most common in dogs over 7 years old. As dogs age, their metabolism slows, and their body's ability to regulate fat distribution may decrease—making fatty tumors more likely.



2. Breed Predisposition

Some breeds are more prone to developing lipomas, including:

Labrador Retrievers

Doberman Pinschers

Cocker Spaniels

Dachshunds

Weimaraners

This suggests that genetics may play a role.



3. Obesity

Overweight dogs seem to be more likely to develop lipomas, although thin dogs can get them too. Excess body fat may make it easier for fatty deposits to form, but lipomas don’t necessarily shrink with weight loss.



4. Diet and Toxins

While not definitively proven, some holistic veterinarians believe that processed foods, poor-quality diets, and environmental toxins may contribute to the formation of lipomas. Feeding a dog fresh, whole foods without artificial preservatives or additives may help reduce toxic buildup in the body.



5. Liver Function

The liver is the body’s detoxifier. If it’s not functioning well, fat and toxins can build up, possibly contributing to lipoma formation. Supporting liver health through diet and supplements may be helpful in some cases.



Are Lipomas Dangerous?

Most lipomas are benign and don’t require treatment unless they grow large or are located in a problematic area. However, it’s important to have any lump checked by a vet to rule out more serious conditions like liposarcomas (malignant fatty tumors).



Can Lipomas Be Prevented?

There’s no guaranteed way to prevent lipomas, but these tips may help reduce the risk:

Feed a fresh, minimally processed diet with high-quality proteins and healthy fats.

Maintain a healthy weight through regular exercise and portion control.

Avoid exposure to toxins, such as chemical flea/tick treatments or synthetic food additives.

Regular vet check-ups to catch any changes early.



Final Thoughts

While lipomas can be unsettling to discover, they’re usually nothing to worry about. Still, understanding the potential causes and supporting your dog’s health through clean nutrition and a toxin-free lifestyle is always a good idea. As always, if you find a new lump on your dog, have your vet take a look just to be safe.

-Valerie San Nicolas CPCN