Hypervitaminosis A in Cats: A Preventable Nutritional Welfare Problem

Hypervitaminosis A from excessive liver feeding causes painful bone disease in cats, representing an entirely preventable dietary welfare failure.

Key Facts

Cats fed exclusively or predominantly raw liver develop hypervitaminosis A from the organ very high vitamin A content.
Excessive vitamin A causes new bone formation on the spine and joints, causing progressive painful deformity.
Cervical spondylosis, fusion of cervical vertebrae, is the classic clinical presentation of this condition.
Affected cats show neck stiffness, reluctance to groom, and progressive forelimb lameness.
The condition is irreversible; bone changes persist even after diet correction, though progression stops.
Prevention requires limiting liver to no more than 5 percent of total diet by weight.
Raw feeding trends have led to a resurgence of this historically declining condition in some countries.

Welfare Considerations

Hypervitaminosis A is a welfare tragedy because it is entirely preventable through basic nutritional knowledge. Cats fed excessive liver suffer progressive painful bone disease that limits their ability to groom, move comfortably, and engage in normal behaviours for the remainder of their lives. The bone changes are permanent. The resurgence of this condition in cats fed raw meat diets reflects the spread of dietary advice that bypasses species-specific nutritional science. Veterinary nutritionists and general practitioners must communicate liver feeding limits clearly to cat owners, particularly those following raw feeding protocols that may include large quantities of organ meats.

What You Can Do

Limit liver and other organ meats to no more than 5 percent of your cat total diet.
Seek guidance from a board-certified veterinary nutritionist before implementing a raw feeding programme.
Recognise neck stiffness and reduced grooming as potential signs of nutritional bone disease.
Ensure any commercial raw diet you feed has been formulated by a veterinary nutritionist.
Advocate for nutritional education inclusion in cat welfare guidance provided by shelters and breeders.