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Why Is My Siamese Cat So Small?

Cats with in the same breed vary in size just like people do. Before you ask why is my Siamese cat so small, there are several variables you need to take into consideration. You might find it isn’t so small after all.

The modern Siamese cat is naturally small compared to many cats. Before you begin worrying that yours is too small, look at the factors that cause variations in size such as the size of its parents, age and diet.

Hopefully, you’ll realize your Siamese cat is not so small after all.

Why is my Siamese cat so small? Siamese kitten

Factors that affect a Siamese cat’s size

There are so many variables that can affect a Siamese cat’s size. Take these into account and you’ll probably stop thinking your cat is so small.

Breed and breeding

Siamese cats are a small breed. There are three distinct types:

  • the traditional Siamese
  • the modern Siamese
  • the classic Siamese

The traditional Siamese cat is well muscled and usually weighs between 8 and 15 pounds.

Why is my Siamese cat so small? Laying on side

The modern Siamese cat is a product of selective breeding. It has more extreme features including a long, wiry muscular body; a slim, wedge-shaped head; piercing blue eyes and oversized ears. It tends to weigh 6 to 12 pounds.

Why is my Siamese Cat so small? Modern Siamese

The classic Siamese is a combination of the traditional and modern Siamese. This cat can vary in size and weight. It can vary in weight from 6 to 15 pounds.

Some breeders produce small Siamese cats by selecting smaller breeding cats. The resulting kittens can grow into petite adults but some can still reach average sizes.

Early nutrition

If a Siamese kitten is separated from its mother too soon, it misses out on vital nutrition in the early stages of its life that can affect it’ overall size in later life. This means it might be smaller tan it should have been but doesn’t necessarily mean it is unhealthy.

If a Siamese cat was purchased from a breeder with too many cats, there’s a chance it missed out on food because if competition with other cats. It might be a little skinny but will gradually catch up to the weight it should be once you are feeding it a balanced diet.


Male Siamese cats tend to be larger than females. A healthy adult male should weigh between about 8 and 15 pounds, and a female tends to be 6 to 13 pounds. Measured at the shoulder, a male ranges from 10 to 14 inches tall whereas a female is usually 9 to 13 inches.

The above weights and heights are just averages and there will always be smaller and larger Siamese cats. It is quite possible for females to be bigger than males, even from the same litter.

Why is my Siamese cat so small?  Siamese curled up


Age plays a large role in the size of a Siamese cat. Like all breeds, they continue to grow until they reach maturity.

These are the life stages of a Siamese:

  • Phase 1: Kitten (0 – 6 months) – Dramatic growth occurs during this stage. A newborn weighs about 4 to 6 ounces. By 2 weeks, a kitten’s weight is often doubled. By 8 weeks a kitten can be anything up to 3 pounds and by 6 months it can weigh as much as 8 pounds.
  • Phase 2: Junior (6 months – 2 years) – at this age, Siamese cats are full of energy. Their activity levels mean they stop gaining weight as rapidly. Therefore, you might not see a huge difference in weight at this stage but will notice an increase in height and length until the age of 12 months. Most Siamese cats reach their full height and length by 12 months but continue to gain weight until the age of 2 years.
  • Phase 3: Adult (2 – 10 years) – at this age as long as a Siamese cat is active, it should maintain its weight as long as it is eating the correct amount of food every day.
  • Phase 4: Senior (10 – 15 years) – This is the stage where some Siamese cats lose weight and some gain it. If your senior cat loses its appetite and begins to decrease in size, a vet should examine ti to ensure it has not developed a health condition. Gaining weight occurs when senior cats become more lethargic. Swap to senior cat food which has fewer calories.
  • Phase 5: Super senior (over 15 years) – Super senior or geriatric cats tend to lose muscle and weight. Ensure your cat gets plenty of fluids and has regular health checks too.
Why is my Siamese cat so small? Siamese drinking

Diet and water

A Siamese cat needs a healthy, balanced diet with all the recommended nutrients. Good-quality prepared cat food has everything necessary for good health. Protein is a very important component of a Siamese cat’s diet and is essential to help it grow at the right rate.

Cats generally only eat when they are hungry (unless they are bored). Ensure you know your Siamese’s weight and provide the correct amount of food daily, divided into 2 to 3 meals. Underfeeding leads to weight loss and poor health as much as overfeeding leads to weight gain and the health problems that go with it.

Some Siamese cats can be quite picky eaters and have been known to stop eating if their food is not to their liking. It doesn’t take much for a Siamese to lose weight so keep an eye on how much it is consuming.

Water is very important but cats are seldom seen drinking. Clean water should be offered every day. Try a cat fountain if your Siamese shows a preference for running water.

Wet food is the easiest way to keep a cat hydrated. Dry food only diets can be a problem for cats that don’t drink a lot. It is also calorie dense which is great if you are trying to get a cat to gain weight but not so good if you are trying to get one to lose or maintain weight.

Why is my Siamese cat so small? Gliding Siamese


If your Siamese has an indoor life you may find it is heavier than it should be rather than too small. On the other hand, Siamese cats that have an outdoor life use up a lot more energy and so tend to look smaller than indoor Siamese cats.

Makes sure your indoor Siamese cat has places to scratch and flex its muscles along with areas to runs, jump and climb to keep it fit and healthy. Its environment should be as enriched as possible. A bored cat can overeat or undereat and develop stress and anxiety problems.


If you are feeding your cat the right amount for its age and still think it’s small than it should be, it could have an underlying health problem. Here are a few conditions that lead to weight loss, all of which require a vet’s diagnosis and then the relevant treatment:

  • Hyperthyroidism – This makes a cat’s metabolism go into overdrive. It will eat constantly, always seem hungry and will lose weight. Its heart rate will be elevated, it will sleep a lot less than usual and meow more than usual. Some cats also drink and urinate more.
  • Diabetes – Signs are drinking excessively, urinating more than usual, eating well yet losing weight.
  • Stress or depression – Many things can bring this on in cats. A new pet in the home, a house move, boredom, loneliness, and poor treatment are just a few causes.
  • Intestinal parasites – If an otherwise healthy cat loses weight, have a vet examine it for intestinal parasites such as worms. These can be treated with medication and your cat will then gain weight. Beware, these can be contracted from raw meat!
  • Kidney disease – This can lead to weight loss. After a full diagnosis, medication and a modified diet can really help
  • Cancer – This is something that usually affects older rather than younger cats. It is so difficult to determine if it is cancer that’s causing weight loss as other symptoms are often well concealed by cats. If your vet has ruled out other common causes of weight loss, a scan can be used to detect tumors.

Why is my Siamese cat so small? – Conclusion

Your Siamese cat might be small but still the perfect size for its build. Take into account the average sizes for the variations of this breed.

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