What should my cat not eat? Foods poisonous to cats
Onions contain the substance allyl propyl disulfide, which destroys cats’ red blood cells. This causes a form of anaemia. Garlic also contains this substance, but to a lesser extent.
Theobromine is a substance in chocolate that is extremely poisonous to cats. It can cause diarrhoea, vomiting, anxiety and (in extreme cases) fits.
Grapes & raisins
Although fruit is not generally bad for cats, it is better not to give them any grapes (nor raisins). They contain a substance that is bad for cats. It is not yet known what substance is the culprit, but prevention is better than cure.
Most cats are lactose-intolerant. What this means is that lactose (milk sugar) and dairy products can cause flatulence to your cat.
Please do not give your cat raw eggs. Eggs contain avidin, an anti-vitamin that adversely affects the metabolism of fats, sugar, amino acids and energy.
Seasoned / marinated meat or fish
Avoid giving your cat meat or fish that is in any way salted, seasoned or marinated. Seasoning often contains onion or garlic, which is bad for the red blood cells of your cat, and can cause anaemia.