Why Is My Hamster Losing Weight? (You Must Know)

Sudden weight loss is a major concern among Hamster owners. The weight of our Hamsters also indicates their health. It is a very common question among Hamster owners, ‘Why Is My Hamster Losing Weight?’. Therefore, I decided to do a little research and consult my veterinarian friend to find the answer.

Some of the major causes that trigger weight loss in Hamsters are malnourishment, improper diet, oral or dental commplications and stress. If your Hamsters is losing weight continiously, it can be fatal for their life. If you have any suspicions about your Hamster’s health, take them to a vet.

A small variation (10-30 grams) in their weight over days is normal, and you should not be worried about the same. There are several reasons that lead to weight loss in Hamsters.

Hamster Essentials
Hamster Essentials

If your Hamster has lost anything above 60 grams in recent days then it can be a major concern for you. Researches show that there have been a lot of instances of high mortality rate in Hamsters after regular weight loss for a few days.

If you see any other symptoms of change in your Hamster’s behavior along with weight loss then it is advised to make a visit to the vet.

Picture Credits: Dora, The Syrian Hamster; Instagram Handle: thehamstercalledmouse

How Do You Know If Your Hamster Is Too Skinny?

In most cases, Hamsters are slim but if they have lost a lot of sudden weight or are underweight, then we can say that our Hamsters are too skinny.

You must weigh your Hamster every few days (once in a week or so). This will help you keep a note of their weight and you will know if they are losing weight suddenly.

If you do not build a habit to weigh your Hamster, it will be a little tough for you to realize if your Hamster starts to lose weight. Therefore, it is important to keep track of their weight.

It is advised to measure your Hamster’s weight every week so that you come to know if they are underweight.

Some Hamster owners do not weigh their Hamsters, so it is a little harder for them to know if their Hamster is underweight. So, it is always a good idea to track the weight of your Hamster.

If you have not weighed your Hamster before, then look out for these signs to find out if your Hamster is underweight:

  • Ribs, spine, and pelvis can be easily seen or touched.
  • Skin feels rough and pulled up.
  • Them squeaking a lot.
  • You will notice less dropping in the cage.
  • The abdominal curve might be carved in.

Sleeping a lot and not willing to move might also be a symptom that your Hamster is underweight.

If such symptoms are noticed by you, consider seeking medical advice immediately.

Causes Of Weight Loss In Hamsters

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

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

  • Overgrown teeth: Hamster’s teeth grow throughout their lifetime. Sometimes, these overgrown teeth start to hurt their gums and even food pipe. This can cause a lot of pain, and thus they stop eating their food.
  • Malnutrition: Some Hamsters are born malnourished and due to this have a robust growth or never reach their potential body weight.
  • Health complications: Some health complications such as gastrointestinal diseases can lead to poor appearance or abnormal growth in Hamsters. Also, metabolic issues, urinary tract infections, and organ failures can also lead to weight loss in Hamsters.
  • Improper diet: If your Hamster has an improper diet, then there are high chances that they will grow underweight. You must your Hamster with a perfect balance of fruits, vegetables, pellets, and treats.
  • Stress: In some cases, stress can often lead to loss of appetite and weight loss in Hamsters. Some of the common factors that lead to stress in Hamsters are improper living environment, the presence of other pets around their cage, sudden change in their diet, etc.

I found this amazing Watermelon print, OMEM Hamster Bowl, your little one will surely love this. Check it out!

OMEM Hamster Food Bowl Ceramic Prevent Being Tipped Over Small Animal Water Dish for Guinea Pig Rodent Gerbil Cavy Hedgehog Feeding Bowl (Watermelon)
  • Hamster Food Water Bowl✔ Diameter:3.14 inches; Height:1.57 inches; Weight:0.38 lbs
  • Easy to Clean✔ The ceramic bowl is easy to clean and hygienic and its weight means...

Do Hamsters Lose Weight In Winters Or Summers?

Season does not affect your Hamster’s weight. So if your Hamster is overweight, the season is probably not its cause.

Although, your Hamster might look fat in winters because they grow their fur. They do it for extra insolation and being warm during winters.

They will shed their hair again before summer, which makes them lighter and make them look a little smaller but the fur does not make a difference in their weight. 

If your Hamster is losing weight it is due to other reasons and the season has nothing to do with it.

Hamster Losing Weight And Fur

Loss of weight and fur in Hamster is often a sign of mites. Some of the symptoms you need to look out for if your Hamster is suffering from mites are as follows:

  • Hair and weight loss
  • Unwillingness to move
  • Lethargy
  • Thick skin followed by crust and yellowish skin

If you notice such symptoms, then it is recommended to see a vet as soon as possible. If it is left untreated, mites can lead to the death of your Hamster.

Shedding can also lead to hair loss in Hamsters but it does not affect their weight. So, you might need to look for symptoms of some other diseases.

You can either get a wooden made hiding spaces for your Hamsters or fleece made snuggle bed, which they can get into and feel at home. These are some of my favorites.

Hamster Losing Weight And Not Eating

A decrease in appetite is directly proportional to weight loss in Hamsters. If your Hamster stops eating, they will lose weight ultimately. They might not eat because of several reasons:

  • Dental Problems
  • Food of bad quality
  • Respiratory or urinary infection

It is recommended to visit a vet if your Hamster is not eating and losing weight. There might be some dangerous health-related problems with your Hamster.

Hamster Losing Weight But Eating

There can be various reasons due to which your Hamster might be losing weight despite eating. Some of the reasons are listed below:

  • Diabetes
  • Improper balance in their diet
  • Inability to extract nutrients.

If our Hamsters have diabetes, they will lose weight in no time. In such cases, we must consult a vet.

Some Hamsters have worms and parasites in their guts, which might suck all the nutrients which our Hamster intakes.

Also, some of the hamsters have a very weak digestive system due to which they cannot absorb nutrients properly. So, they start to eat to eat their own poop, to reabsorb the extra nutrients.

In some cases, an unbalanced diet might lead to weight loss in Hamsters. If our Hamster continue to eat only one kind of food each day then their body might not gain enough calories and fiber.

Therefore, it is important to severe your Hamster with a balanced diet.

Hamster Losing Weight And Drinking A Lot Of Water

If you ever notice your Hamster drinking a lot more water than usual days and losing weight at the same time, then it can be a sign of diabetes.

Diabetes is very common in Hamsters and due to this, they end up losing a lot of their body weight. Some of the symptoms of diabetes are as follows:

  • Wet bottom
  • Infection in their urinary tract
  • Frequent urination
  • Rapid cataract formation.

If you notice any of these signs, then there are high chances that your little one is suffering from diabetes.

You can treat diabetes in them by controlling their diet. You must make a visit to a vet. They will diagnose your Hamster and will help you further with the treatment.

Do Hamsters Lose Weight Before They Die?

Some Hamsters starts to lose weight before their death while others don’t. However, you will notice that your Hamster starts to lose some weight once they become older.

You must change the diet of your Hamsters according to their weight change. You can throw in some extra pellets and a cup of fresh veggies if your Hamster is underweight.

Despite this, if your Hamster appears to lose weight, then you must consult a vet. This can also be sign of severe digestive or dental disorder in them.

How To Help Hamster Gain Weight?

If your little one has lost weight or is underweight, it is important to do something to get back on track.

However, before trying anything, you must consult a vet regarding the same. They will guide you if your Hamster is losing weight due to some health issues.

In some cases, gastrointestinal parasites, dental problems, or even stress can cause weight loss in Hamsters.

once you consult a vet, we can try some other simple ways to help our Hamsters gain some weight. Listed below are a few tips:

  • Add some extra pellets in your Hamster’s die. If your Hamster has a history of bladder stones, then adding extra pellets can be risky for your Hamsters
  • If you want your Hamster to gain some weight, do not add too many calories into their diet at once. This might go wrong and make your Hamster suffer. Their digestive system can disbalance. Always introduce the food slowly, this will ensure gradual but healthy weight gain in your Hamster.
  • You can feed Oxbow care or Sherwood pet recovery formulae to your Hamsters twice a day. It will help in your Hamster’s weight gaining process as it contains some vital nutrients.
  • You can feed your Hamsters with some occasional treats in the form of fresh fruits like apple or banana.
  • Adding some oatmean in their diet plan is alwys an amazing optoion as it is very healthy and helps in wieght gain

You must keep in mind that your Hamsters have s very sensitive digestive system. Therefore, frequent introduction of some new food or frequent changes in their diet can cause health complications in our Hamsters.

Best Food For An Underweight Hamster?

You must feed your Hamster a perfect balance of pellets, fruits, vegetables and treats.

wPicture Credits: Mouse, The Syrian Hamster; Instagram Handle: thehamstercalledmouse

If your Hamster is underweight, then you can throw in some extra pellets or a cup of fresh veggies in their diet.

You can split up the veggies in two to four feedings of small portions rather than one large portion.

You can feed your Hamsters 1/6 cups of pellets every day. Serve only good quality pellets to your Hamsters. It would be a better choice to serve them with Vitamin C fortifies pellets only.

High-Calorie Foods For Hamsters

Have a look at the table below to find some good choice of high-calorie food mix for your Hamsters:

GrapesBell pepper

You must keep in mind that it is important to introduce a new food to your Hamster’s diet very slowly. Also, be careful with your Hamster’s food habits as high sugar food can lead to health complications such as diabetes and cancer in Hamsters.


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.

Recent Posts