Thiamine Deficiency in Cats

Thiamine A Deficiency in Cats


Vitamin B1, also known as thiamine, is an essential vitamin for cats, which means it must be part of their diet in order for your cat to maintain optimal health.  The brain and other high energy organs require thiamine for proper function because it is used for carbohydrate metabolism.  If a cat does not get enough thiamine in their diet, you will first notice a lack of appetite, weight loss and GI upset.  As symptoms progress, cats will experience neurological symptoms such as neuromuscular weakness, unequal pupil sizes and decreased light response by the pupils.  Extreme cases can lead to heart problems.


Over the past 5 years, there have been several major recalls of commercial pet food due to insufficient thiamine content.  Thiamine is sensitive to heat and water soluble so it is not a very stable vitamin when exposed to high heat from food manufacturing processes.  Certain drugs like diuretics that cause increased fluid loss can deplete a cat’s thiamine.  Some cats simply have a higher demand for thiamine due to poor nutrient absorption in their intestines.  All of the factors can potentially lead to thiamine deficiencies in your cat.


The Association of American Feed Control Officials (AAFCO) recommends that adult cat food provide 5 mg of thiamine per kilogram of food – that’s over 3 times what a dog needs!  The most common sources of thiamine are liver, meat, brewers yeast, dairy and whole grains.  Because thiamine is water soluble, it is very safe and there is little concern of over dose from too much thiamine.  Excess levels will be excreted in the urine.  Providing your cat with a healthy multi-vitamin is a great way to ensure that your cat is receiving all of the vitamins they need in appropriately balanced levels.






Clinical signs, MRI features, and outcomes of two cats with thiamine deficiency secondary to diet change.


Naturally-occurring and experimental thiamin deficiency in cats receiving commercial cat food.