Why Is My Hamster Fat All Of A Sudden? (You Must Know)

Every owner wants to give the best care and life to their Hamsters. But sometimes, your Hamster might start eating too much and become overweight. Keeping your Hamster’s weight in a healthy range is very important for its health and general well-being.

Hamsters can get fat quickly if they over eat the energy rich foods, like commercial dry hamster food or heavy treats, and don’t take enough exercise. A healthy adult hamster that is gaining weight may need its diet altered to prevent it becoming over weight.

However,the good news is that hamster obesity is often solved by correcting your pet’s diet and encouraging more exercise. You can help your Hamster lose weight and become a happy and healthy pet again.

How Heavy Should My Hamster Be?

Hamster Essentials
Hamster Essentials

The weight largely depends on the species of your Hamster, but here are some rough guidelines.

  • Syrian or Teddy Bear hamster weight – 3.5 to 7 oz (100 – 200g).
  • Chinese hamster weight – 1.5oz – 1.8oz (40 – 50g).
  • Roborovski Dwarf hamster weight – 0.7 to 0.88 oz (20 – 25g).
  • Russian Dwarf hamster – 1.5 to 2 oz (40 – 60g).

The weight should gradually increase as your Hamster gets older.

Of course, this will vary based on your Hamster, which is why it’s important to take your pet for regular checkups with the vet to ensure that they are the right weight for their age and gender.

Sometimes there are medical conditions that can cause weight loss or gain, such as a parasitic infection, so if your Hamster is too small or too big then your vet can help you to figure out what’s wrong before you change their diet.

How Do I Know If My Hamster Is Too Fat?

As we have mentioned, start worrying if your hamster crosses its ideal weight.

Be your own judge and start worrying if you notice any changes in the behavior, such as movements and energy levels.

You should weigh your Hamster weekly since it’s born or from the moment you get it. You can use kitchen scales or jewelry scales such as these, that weigh to the nearest 0.1 grams. Document weekly/monthly weight gain or loss to make any decisions.

What Causes Obesity In Hamsters?

There are a lot of reasons that can cause weight gain in Hamsters. It can be a major concern for Hamster owners if their little one is gaining weight consistently. Therefore, it is important to address this issue immediately.

Most of the owners struggle to find the cause of weight gain in their little ones. So, I decided to consult a vet and share some basic factors that trigger rapid weight gain in Hamsters. Here are a few to start with:

Feeding Your Hamsters Excessively

Sometimes new hamster owners often spoil their little pets with unhealthy food out of love or lack of food knowledge. This can have a negative impact on your Hamster’s health.

However, being a responsible hamster owner, you must take care of your Hamster’s diet and feed them with the appropriate food.

Overfeeding even healthy food can prove to be a problem for your Hamster.

In addition, new pet parents are often overwhelmed by the number of species-appropriate food available on the market.

This often leads to them failing to choose quality food for your pet could lead to undesirable results for their precious health.

Heavy Treats

Just like we humans, hamsters too crave treats. Besides this, treats are an amazing way to bond with your pet and appreciate them. However, it is important to serve these treats in moderation.

As long as you serve them treats along with their healthy diet, you are good. Giving heavy treats more often makes them lose appetite for their usual diets.

Unfortunately, bad treats seem more tempting than good ones. Assuming whatever you crave will be suitable for your Hamster is wrong.

Most commercially available Hamster treats are no good. To avoid obesity in your hamster, do not feed them stuff high in sugar and starch.

Lack Of Exercise

If your Hamster does not give enough time for its physical stimulation, it might be a bad sign.

Lack of energy spent each day can often result in obesity in Hamsters.

As with humans, not providing enough room or time to your pet for body movement and leg stretching, they tend to get fat. As well as not allowing them out of the cage leads to physical deficiencies.

In addition, if your Hamster consumes too many calories and does not burn them, the obesity kicks in, and they feel more sluggish.

Unfortunately, the lack of exercise in fat Hamsters leads to life-threatening situations, and your beloved friend ends up having a shorter lifespan.

Health Problems That Make Your Hamster Fat

Certain medical conditions often lead to obesity in Hamsters.

Particularly if you own a female Hamster, being pregnant could be the reason to weight gain.

This significant increase in weight is about 80 percent, which is divided throughout the tissues naturally.

Some other medical causes for your little friend to look more rounded are tumors or bloat.

Often in Hamsters, excessive gas gets trapped in organs which forms bloat and makes their belly sore, hardened, and swollen. Bloating is a serious emergency that needs timely vet care.

Dangers Of Having A Fat Hamster

There are several things that can become an issue as a result of being overweight. We talk about it in humans frequently, with more focus than ever being put on living a healthy lifestyle, but it is rare that we extend this to our pets.

However, a hamster that is overweight is at risk of developing some serious health conditions, some of which could end up being life-threatening.

Hamsters are far more susceptible to developing problems with the internal organs when they are overweight. This can include problems with the heart, which could be fatal.

Furthermore, your pet may become even become lazy. They will prefer to stay in a corner of their cage and not show any movements.

Finally, Hamsters who are too big may live shorter lives. This is mainly in relation to the associated health conditions and lack of correct nutrients.

We see this shorter lifespan in humans who are obese, but many people do not realize that this weight condition can drastically affect their pets as well.

How Do I Get My Hamster To Lose Weight?

On your part, there are a few things that you can do to keep a check on your Hamster’s weight.

If you have an obese Hamster, you should provide your little pet with a proper dietary regime and exercise routine. This is essential to maintain a long and healthy life.

Proper Diet

To keep your Hamster in shape, it is important to provide them with a healthy diet.

Chances are, you are feeding foods with high-fat content. To get your Hamster to lose weight, it is a given that foods high in fat and sugar need to be either reduced or taken out of the diet.

Feeders referred to as worms (i.e. mealworms, black soldier fly larvae, etc.) are actually larvae that are high in fat. Heavily reduce the feeding of larvae.

Let them turn into beetles which are half the fat and then feed them. On a side note and just as a matter of interest, beef has a higher fat content than mealworms.

Reduce fruits in the diet and increase the percentage of dark leafy greens, flowers, and gut-loaded insects.

To speed up the weight loss a little more, offer dark leafy greens daily but leave a day or so in between feeding insects and other foods.

Alternatively don’t feed at all for a couple of days in a week. Assuming your Hamster is healthy outside of being fat (or obese), do not worry if it refuses any foods other than those which have led to the condition in the first case.

Sometimes habits take a little while to change and being hungry is a good incentive.

Make An Exercise Routine

Diet and exercise go hand in hand.

You should spend some time with your Hamster daily in a safe environment and urge him to play and explore.

However, never try to push him too much in the start to avoid any stress on his body and increase it gradually.

Provide a larger cage and use toys to hide healthy treats in every corner for them. So every time with curiosity, they move around and forage for food and treats.

What Foods Make Hamsters Fat?

The main cause of obesity in Hamster is an unhealthy diet. It is common for people to feed their Hamstertoo many treats (because they are just so cute when they beg), or give them a dietl ow in the essential nutrients.

In addition, while it is okay to give your hamster the occasional treat, you want to avoid giving them more than a tablespoon in a day.

Too many sugary treats can cause rapid weight gain in Hamsters, and they can be the cause of an imbalance in the gut, making the Hamster more likely to suffer from a digestive-related disease or condition.


Hello, I am Mohini, the founder of this blog. I am a qualified Animal Nutrition. I am here to help everyone understand their pets better.

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