The Power of Thiamine: Why Vitamin B1 Matters in Your Cat’s Diet

When it comes to raising healthy, happy cats—especially kittens—Thiamine (vitamin B1) is one of the most overlooked yet crucial nutrients. Whether you're a breeder, a rescue foster, or a dedicated cat owner, understanding the role of thiamine can make a world of difference to your feline’s health and wellbeing.

What is Thiamine?

Thiamine is a water-soluble B vitamin essential for normal nerve function, carbohydrate metabolism, and brain development. Cats, unlike some species, cannot synthesise or store thiamine in large quantities, so they rely entirely on consistent dietary intake. A deficiency can arise quickly—within just 2–3 weeks—and can be life-threatening if not corrected promptly [1, 2].

Why is Thiamine So Important for Cats?

In growing kittens and breeding queens, thiamine plays a critical role in early development. A deficiency can result in:

• Irritability and failure to thrive

• Poor suckling and rooting behaviours

• Neurological symptoms such as ataxia, seizures, and head tilt

• Vestibular signs, including loss of balance and deafness

• In severe cases, sudden death

These effects are particularly concerning in breeding programmes where early nutrition is key to healthy litters.

Studies have shown that thiamine deficiency in cats leads to bilateral symmetrical lesions in the brainstem and midbrain, associated with vestibular signs and seizures [3, 4].

How Much Thiamine Do Cats Need?

• Minimum daily intake: ~0.33–0.35 mg per day for an adult cat [5]

• Therapeutic or supplemental dose: ~15 mg/kg body weight

• Dietary guideline: Add ~2 mg of thiamine per kg of food

However, thiamine has a strong odour, and excess can make food unpalatable. Striking the right balance is essential.

⚠️ Important Note:Thiamine tablets have a strong sulphur-like odour that many cats find unpleasant. While overdosing thiamine is not toxic, it can lead to food refusal, especially in fussy eaters. Always start with small amounts and ensure palatability is maintained.

Best Dietary Sources of Thiamine

🟡 Egg Yolk – Natural & Bioavailable

Egg yolks are a rich, bioavailable source of thiamine—providing approximately 18 mg per yolk along with essential fatty acids, B vitamins, and trace minerals.

• Dose guide: Add 1 yolk per 4 kg of food to meet thiamine needs.

• Many breeders report significant improvements in coat quality and kitten vitality when feeding yolk regularly.

“Now that I have my own chooks (who eat any of the cats' leftovers), I’ve started adding a yolk per kg of food. The improvement in coat texture and sheen has been remarkable.”

💊 Pharmacy-Sourced Thiamine or B-Complex Tablets

• 50 mg thiamine tablets are inexpensive (~$7 for 100) but may require a chat with the pharmacist as they could be prescription only, alternatively you can buy on iherb.com very cheaply.

• Use ¼ of a tablet per kg of food, which supplies ~12.5 mg—well above the dietary requirement, but still safe.

You can also use a B-complex vitamin, checking the label for exact thiamine content.

Tip: Introduce supplements gradually and avoid excessive doses to prevent smell-related food refusal.

Best Practice: Use a Combined Approach

Using both egg yolk and a thiamine supplement is often the most reliable strategy:

• Egg yolk provides bioavailable nutrients and a natural food source

• Thiamine tablets offer predictable dosing and dietary certainty

This ensures your cats receive both quality and quantity—covering all bases, especially during pregnancy and kitten growth phases.

Final Thoughts

Thiamine is one of the simplest, most affordable nutritional interventions you can make—and its impact is enormous. From neurological protection to kitten development, this small but mighty vitamin is a must-have in any feline feeding plan.

🐾 Healthy food = healthy brains = happy cats.

whole eggs contain 18mg thiamine or vitamin B1 per yolk.

Thiamine or vitamin B1 in its purist form sourced from iherb.com

References

1. National Research Council (2006). Nutrient Requirements of Dogs and Cats. National Academies Press.

2. Markovich, J. E., Freeman, L. M., & Heinze, C. R. (2013). Thiamine deficiency in cats fed commercial diets. Journal of the American Veterinary Medical Association, 243(5), 649–655. https://doi.org/10.2460/javma.243.5.649

3. Penderis, J., & Dennis, R. (2004). Thiamine deficiency-associated central vestibular syndrome in a cat. Journal of Feline Medicine and Surgery, 6(6), 383–388.

4. Gieger, T. L., & Hosgood, G. (1995). Thiamine deficiency in a cat: a case report and review of the literature. Journal of the American Animal Hospital Association, 31(4), 324–328.

5. Zoran, D. L. (2002). Nutritional management of the dog and cat. Journal of the American Veterinary Medical Association, 220(11), 1529–1533.