Poinsettias are generally over-rated in toxicity.  If ingested, poinsettias can be irritating to the mouth and stomach, and may cause mild vomiting or nausea, but are not normally fatal. 
 
Mistletoe has the potential to cause cardiovascular problems.  However, mistletoe ingestion usually only causes gastrointestinal upset. 

 Holly ingestion could cause vomiting, nausea, diarrhea, and lethargy.

Chocolate, or more precisely cacao contains a compound called theobromine which has four different adverse effects on cats:

It is a stimulant which increases the heart rate.
It is a diuretic (increases production of urine) resulting in increased loss of body fluids.
It causes stomach upset.
It acts on the nervous system.

The symptoms will very depending on the amount of chocolate the cat has eaten. The most common symptoms are:  vomiting, diarrhoea, excessive urination, nausea, seizures, irregular heartbeat. A larger dose of chocolate may well cause a coma or death. Symptoms usually start within a few hours of ingestion but can take up to 36 hours. If you think that your cat has eaten chocolate, don’t wait for the symptoms. Try to induce vomiting and contact your vet asap.

Not all chocolates are equally dangerous because different chocolates contain different levels of theobromine. As mentioned above, theobromine is found in cacao, so  the higher the percentage of cacao in the chocolate, the more poisonous the chocolate is. For example, milk chocolate contains 60mg of theobromine per oz whereas dark baking chocolate contains 450mg/oz.  As a general rule, the more cacao in the chocolate, more dangerous the chocolate is. 45-50mg of theobromine per pound of body weight is sufficient to poison a cat; and 45-50mg is just 0.1oz of dark chocolate!

Why is chocolate poisonous to cats?
Whereas humans can metabolize theobromine effectively, cats cannot. If cats are fed with chocolate the theobromine remains in their bloodstream for up to 20 hours. The lack of clearance will result in the accumulation of  theobromine, which will quickly reach toxic levels. Nor are cats the only animals which cannot metabolize theobromine. Chocolate is also toxic to horses, dogs, voles and parrots.
 

Unhealthy teeth and gums have greater impact on the body than just causing bad breath, pain and infection. As the gums have a rich blood supply, bacteria is readily transported to other organs (such as the liver, heart and kidneys)  causing damage and even organ failure. It is important to have bad breath checked out by a veterinarian as quickly as possible.

The most common causes of halitosis in cats are:

Stomatitis

Gingivitis

Tooth decay

Tooth abscess

Foreign body trapped in the mouth

Diabetes

Kidney disease

Liver disease

Cancers of the mouth

Gastrointestinal problems (obstructions, cancer, infection)

These are some possible symptoms if the problem is dental:

Unwillingness to eat

Drooling

Poor coat condition, due to reluctance to groom

Red, swollen & or bleeding gums

Tartar (calculus) deposits on the teeth

Pawing at the mouth

If the problem is non dental these symptoms may occur;

Polyuria (increased urination)

Polydipsia (increased thirst)

Weight loss

Lethargy

Diarrhea

Vomiting

Enlarged liver or kidneys

If in doubt always seek professional advice.

Your veterinarian will perform a complete physical examination of your cat, including checking the oral cavity. Diagnosis may be made upon physical examination, or your veterinarian may wish to run some further tests including;

X-ray – To check the condition of the dental roots & bones.

Diagnostic tests to determine liver & kidney function.

FeLV & or FIV tests.
Treatment depends on the underlying cause of the halitosis.

Remove calculus from the teeth & polish.

Extract any diseased teeth.

Treat or manage underlying cause such as diabetes, kidney disease etc.

If you think anything is wrong with your cat, don’t delay. See your vet.
 

An indulgent owner may be to blame, but canny cats also beg at second homes. Fat cats have a shorter life expectancy than normal cats, and just like us, may have to count their calories.

The fattest cat on record is Himmy, a tabby belonging to Thomas Vyse of Redlynch, Queensland, Australia. Himmy weighed 46 lb., 15.25 oz, and died in 1986 at 10 years of age. Fearing people will simply overfeed their cats to top the record, a fully justifiable reason, Guiness Book of Records stopped accepting applications for this record.

This is not kindness it is cruelty.