Pet Snakes, Pet Lizards, and Fatty Liver Disease

The term fatty liver disease is common these days for humans but also reptiles. One of the main causes of fatty liver disease is simply eating too much. While remedied by calorie reduction and exercise it can become life-threatening if left untreated for a long period.

Fatty liver disease in reptiles 

The term fatty liver disease gets thrown around more and more in the reptile industry these days. This is a term that we didn’t really use until the last five or so years. I’ve talked about the dangers of overfeeding and power-feeding snakes and lizards a lot over the course of this website. Let’s have a closer look into what many reptile collectors are referring to as “fatty liver disease” in snakes and lizards.

Excessive caloric intake without exercise 

Let’s face it. Our pet snakes and lizards kept in enclosures don’t get the exercise that they would get living in the wild. To further complicate matters, we tend to feed our animals a bit more than they should actually eat. This combination leads to chronic health problems and disease. Overfeeding your reptile could lead to the following problems.

  • Obesity 
  • Abnormal growth 
  • Reproductive problems 
  • Various intestinal diseases 
  • Heart problems 
  • Shorter lifespan 

Of course, all these problems related to obesity can lead to a shorter lifespan. In fact, it’s pretty much guaranteed. A healthy snake isn’t an obese snake. We tend to treat our pets as we do humans. The problem with this school of thought is that they’re not humans. Snakes are snakes and lizards are lizards. They’re cold-blooded and have different dietary needs than humans. 

You should also check out my article on how to think as a snake thinks. Think outside the box of what’s good for a human as opposed to an animal. This is similar to the way some people treat their pet dogs or cats. Often times, people feed dogs and cats food that they shouldn’t eat, like anything chocolate for example. Since this article is specifically about snakes and lizards, I won’t delve into dogs and cats deeper than this. 

Reptile dying from obesity 

There are many causes for pet snakes and lizards to die prematurely. We’re going to stick strictly to diet here. Sometimes we don’t know why our pet snake or lizard dies. Overfeeding is a common mistake among reptile keepers. In fact, it’s one of the most common. When a pet snake or lizard dies prematurely due to obesity, fatty liver disease is a possible culprit. There are also other diseases related to obesity in reptiles. 

Female Colombian boa constrictor
An obese Colombian boa constrictor.

There are a few ways of finding out if your pet snake or lizard died from fatty liver disease. The most certain way is to do a necropsy on the animal. I suggest taking the animal to a qualified veterinarian for this task. In order for you to be able to tell what a fatty liver is, you need to know what a healthy one looks like. This is why if you’re really curious about the cause of death, a professional is the best way to go. 

The cause of death in reptiles

The greatest point I’m making here is that the term fatty liver disease gets thrown around a lot these days and might not be the cause of death in your pet reptile. Still, if the animal suffered from chronic obesity, there’s a very good chance that fatty liver disease is the cause of death. 

Luckily, there are easy ways to avoid fatty liver disease and other obesity-related health issues. First and foremost, know the range of your animal’s caloric intake and don’t overfeed it. One can easily see when their pet snake or lizard is obese. If you see this happening, cut back on the feeding schedule or at least lessen the portions. I’ll give a few examples.

Cutting back on the calories 

First, remember that snakes and lizards kept in enclosures have less exercise than their outdoor counterparts. This is not a call to starve your animal. Instead, one can take a smart approach and trim back the fat in a healthy and productive way. 

Sure, you can take your monitor lizard or boa constrictor outside their enclosure and allow them some time outside their enclosure. That’s helpful as exercise is important for just about all living beings. Still, a lot comes down to calorie reduction. You can also check out my article, Should You Feed Your Snake As Much As It Wants? The short answer to that is no. In nature, food is more limited and it takes some effort to find and sometimes overpower it. 

Examples of caloric reduction in reptiles 

Say you have an adult corn snake that’s obviously plump. It’s to the point that you can easily see the elastic skin stretched out between the snake’s scales. First of all, the snake should only be offered a meal every seven to ten days. Secondly, if you’re feeding your corn snake a small rat, or rat pup, feed it a mouse instead. If the snake is on mice only and is obese, feed the snake a mouse hopper instead of an adult. 

Taking these measures will have your snake dropping excessive fats in a couple of weeks. It’s that easy. Do note, however, that a snake used to eating large meals might become a little temperamental when switching over to smaller meals. You created this monster, you need to follow through and stick with the program. In time your snake will adjust to its new feeding regime and become healthier for it. 

Unfortunately, it’s sometimes too late to save pet snakes and lizards with advanced health issues caused by obesity. This includes power-feeding babies or yearlings who end up with growth deformations. This is an issue that can’t really be completely solved. 

Reptiles susceptible to obesity and fatty liver disease 

Certain species of snakes and lizards are more susceptible to obesity and fatty liver disease than others. Generally speaking, herbivores are less likely to become obese compared to strict carnivores. Omnivores can go either way depending how much animal protein they’re taking in compared to vegetables. 

Obesity in the uromastyx 

Take a uromastyx for example. These lizards take mostly plant matter and little animal protein. They do, however, eat seeds and legumes (lentils and/or beans). There’s a lot of carbohydrates in legumes. In such a case, reduce (not eliminate) seed and legume intake if you notice your uromastyx is obese. 

Obesity and Savannah monitors 

Savannah monitors are highly susceptible to obesity. I’ve seen some Savannah monitors so overweight it’s unbelievable. The problem is, these lizards will eat themselves to death if you allow it. Having a stocky build in such lizards is normal but layers of excess fat, especially around the abdomen aren’t healthy. 

Savanna monitor
Savannah monitor lizards have a tendency to become obese. Be aware of how much you're feeding your lizard and avoid obesity.

Bearded dragons might struggle with obesity too 

Bearded dragons are somewhat susceptible to obesity but not to the point of the Savannah monitor. Still, it does happen. An important thing to remember with bearded dragons is as they get older they need more quality greens and less animal protein (bugs).

Remember, feeders such as wax worms are high in fat making them sweeter in taste. This is why most lizards love eating them. Keep these things in mind. Insects lower in fat (crickets, grasshopper, and roaches) are healthier for your lizards. 


A snakes appetite doesn’t vary from just species to species but also from individual to individual. Some snakes know when they’ve had enough and go on feeding fasts. Sometimes these fasts can last weeks or even months. It’s important to remember that as long as the snake is healthy and not stressed, self-imposed feeding fasts aren’t anything to worry about for the most part. Such fasts also occur during the breeding season in some snakes. I’ve seen this with corn and rat snakes

If you want your snake to trim down some, don’t stop feeding it altogether for a month or two. That’s the wrong way to go about it. You’ll also end up with a really cranky snake. Instead, feed your snake a smaller meal every seven to ten days. 

Obesity in snakes generally occurs with just about any species. The more active the snake is within its enclosure determines how many calories it’s burning. These snakes with higher metabolisms are less likely to become obese. On the other hand, snakes that stay coiled up in a corner for long periods of time burn few calories throughout the day (and night). 


It’s possible that the term fatty liver disease is being used a little too liberally these days. What is common, without a doubt, is that obesity in pet snakes and lizards is running rampant. This is simply due to overfeeding and can be resolved, especially when caught early. Don’t be in a rush for your baby snake to grow to breeding-size in a year. 

Generally speaking, most snakes breed best at three to four years. Be patient and you’ll get better results both with clutch quality, but also your snake’s longevity. If you can’t wait for your snake to reach the proper age of breeding, it’s best to buy well-established adults instead. 

Please leave your comments in the section below! 

Pet Snakes, Pet Lizards, and Fatty Liver Disease

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