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Do Cats Need Vitamins? What Are the Benefits and Risks?

hand giving pill to a cat

Supplemental vitamins can benefit some cats, but whether you should give them to your cat will depend on certain factors. Your cat can get all the vitamins it requires from a well-balanced diet, but in some cases, it may require additional vitamins. In this article, we’ll discuss if and when vitamins are necessary and the benefits and risks of giving them to your cat to help you make an informed decision.


The 5 Reasons Cats May Need Vitamins

Ideally, your cat should get all the vitamins it needs from a healthy, well-balanced diet. However, even if you prepare delicious and nutritious meals for your cat, it may develop vitamin deficiencies due to an underlying condition. Vitamin and mineral supplements can be beneficial for specific situations.

1. Vitamin and Mineral Deficiency

If your cat has been diagnosed with a mineral or vitamin deficiency, supplementing it with vitamins is necessary. Your cat will need to be prescribed a specific vitamin supplement instead of a multivitamin, and it will need to be monitored closely and checked regularly by your veterinarian.

Cats with gastrointestinal diseases, such as irritable bowel syndrome, frequently have a vitamin B deficiency and are given vitamin B12 or cobalamin.

close up of sick-looking orange cat lying on wooden planks
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2. If You Feed Your Cat a Home-Cooked Diet

Home-cooked diets are an affordable way to feed your cat, but they are not always nutritionally balanced. If you prepare food at home for your cat, it is a good idea to supplement it with vitamins. It is best to cook recipes suitable for your cat’s age and designed or approved by your veterinarian, especially if your cat has underlying health conditions.

3. If Your Cat Eats Too Little

Some cats can be picky eaters, while some don’t have a big appetite. This could be because they are ill or just fussy about their food. If this is the case for your cat, they are most likely not receiving a balanced diet, and a multivitamin can help prevent your cat from developing any deficiencies.

cat not eating food
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4. Compromised Immune Response

Cats infected with the feline immunodeficiency virus or a similar illness can be given immune-boosting food supplements.

Many cats that test positive for FIV but show no symptoms of the disease can live happily for years after being diagnosed. These cats need to eat a well-balanced diet and take vitamin supplements to help boost their immune system. They should also be kept indoors to minimize their exposure to diseases.

5. Pregnant and Nursing

If your cat is pregnant or nursing, it can develop deficiencies that require supplementation, specifically if it falls pregnant at a young age, before 10 or 12 months. Consult your vet to determine if your cat needs a vitamin supplement and which one is best.

pregnant white cat
Image Credit: Boy77, Shutterstock


What Are the Risks of Vitamins?

Vitamins are necessary for good health but taking too much or too little can be harmful. If you are considering giving vitamins to your cat, you should always ask your vet first. Whether you choose a single or multivitamin, you must be aware that supplementing a well-balanced diet could create toxicity.

Numerous studies reveal that some supplements have poor quality control. Sometimes, the vitamin can contain more than what is stated on the label, and some brands may also contain harmful contaminants such as lead or mercury. Others may not dissolve in food or water and cannot be absorbed entirely.

Vitamins A and D are the most problematic. The body does well in storing these vitamins but doesn’t do well at eliminating them, and over-supplementing can result in health issues down the line. If your cat doesn’t receive enough vitamin D, it can lead to paralysis, skeletal defects, and other issues, but too much can cause gastrointestinal problems.

An excess of vitamin C can cause the urine to be overly acidic, which can lead to the formation of crystals and a potential life-threatening blockage.

cat taking medicine
Image Credit: Creative Cat Studio, Shutterstock

How Do I Know My Cat Has a Vitamin Deficiency?

If your cat is deficient in certain vitamins and minerals, it will have a notable effect on its coat and skin. This can often occur when a cat is fed low-quality commercial food that lacks the necessary nutrients. When a cat is deficient in essential fatty acids, its skin will become dry and scaly, the fur will mat easily, and ear infections can occur more frequently.

If a cat’s diet is deficient in Vitamin A, it may show in their skin and coat, and they will become lethargic and may suffer from night blindness.

Vitamin B1 or Thiamin is required to metabolize carbohydrates, and if a cat is deficient, it can be affected neurologically. Signs include incoordination, curling of the neck, falling, head tilting, circling, dilated pupils, and seizures. Gastrointestinal signs such as vomiting may also occur.

If you suspect your cat has a vitamin deficiency, talk to your vet so they can run some tests and adjust your cat’s diet if necessary.

Which Cat Vitamins are Available?

There are a variety of single or multivitamins available that you can give your cat, but as we mentioned before, a well-balanced diet should contain all the vitamins and minerals that a cat requires.

Older cats, like humans, may develop health problems. Senior cat vitamins may be required when an elderly cat is unable to absorb certain vitamins or nutrients for whatever reason. If you have a senior cat that appears to be losing mental acuity, you may want to consider a supplement to support cognitive dysfunction. Many studies have shown that antioxidants like vitamins E and C protect and repair brain cells. Again, it is always important to speak with your vet first for your cat’s safety.

vet gives the cat a medicine pill
Image Credit: Irina 1 Nikolaenko, Shutterstock

How Do I Know My Cat is Getting a Nutritionally Balanced Diet?

Cats can obtain the nutrients they require from various ingredients, which they can usually acquire from a well-balanced diet tailored to your cat’s lifestyle and stage. The primary nutrients that a cat will get from its diet are protein, fats, carbohydrates, vitamins and minerals, and water.

To ensure that cats get enough nutrients, only buy foods with an Association of American Feed Control Officials (AAFCO) statement on the label.

orange and white cat eating on an elevated feeder
Image Credit: Princess Anmitsu, Shutterstock

AAFCO requires that cat food for adult maintenance should contain a minimum of 26% crude protein on a dry matter basis to be considered nutritionally complete and balanced. 30% is the bare minimum for growth and reproduction. On a dry matter basis, the AAFCO minimum for fat in all cat foods is 9%.

Healthy cat food should contain the following vitamins:

  • Vitamin A, E, D and K
  • Thiamin
  • Riboflavin
  • Niacin
  • Folic Acid
  • Biotin
  • Vitamin B12
  • Pantothenic acid
  • Pyridoxine
  • Choline

Water makes up most of a cat’s body and is required for nearly every metabolic function. It is one of the most critical nutrients for cats, so ensure your cat is getting an adequate amount. Healthy cats should drink 4 to 5 ounces of water per 5 pounds of body weight, including water from their food.



Healthy cats that eat a nutritionally balanced diet will generally not require supplements, but pets with certain health conditions may benefit from taking vitamins. Before giving your cat a supplement, it is vital to determine if it needs it in the first place, as giving vitamins to a healthy cat can put them at risk for toxicity. You should always consult your vet to determine if vitamins are necessary and which are best, along with dosage recommendations.

Featured Image Credit: Creative Cat Studio, Shuterstock

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