Why is it bad to give a dog chocolate?

They say it is toxic but I have always gave my dog an M&M or a cookie now and then and nothing bad has ever happened.

probly cuz its not toxic at the level of one m&m or a crumb of chocolate but is at higher levels

they say it can make your dog really sick. i give my dogs chocolate all the time [they love it] nothing has ever happened.

Chocolate can make a dog really drunk drugged hyper. I've heard that their heart can race so fast that they just wear themselves out. Now let's see if that is true...http://ask.yahoo.com/ask/20000607.html"The article explains that chocolate contains theobromine, an alkaloid that dogs can't metabolize quickly. If a dog ingests a large amount of chocolate, the theobromine can build up and reach a toxic level of concentration, leading to cardiac arrest. Different types of chocolate are more harmful than others, and the effects will vary, depending upon the size and weight of the dog. However, it is potentially lethal."Check out the link for "the rest of the story."

There's something called Theobromine in chocolate and that is what's toxic to dogs. An m&m here or there won't kill them but in my opinion, why take chances? A little bit of arsenic won't kill you but you probably wouldn't ingest it right? Here is a chart that shows how much is too much chocolate for a dog: Toxic Amounts of ChocolateWeight/Milk Choc/Unsweet. Choc/Mg Theobromine 5 lb. / 4 oz. / .5 oz. / 20010 lbs. / 8 oz. / 1.0 oz. / 40020 lbs. / 1 lb. / 2.5 oz. / 90030 lbs. / 2 lbs. / 3.25 oz. / 130040 lbs. / 2.5 lbs. / 4.5 oz. / 180050 lbs. / 3 lbs. / 5.5 oz. / 225060 lbs. / 4 lbs. / 7.0 oz. / 270070 lbs. / 5 lbs. / 8.5 oz. / 3400

Chocolate, like grapes, is not good for a dog because of toxins in it. A little amount however, will not kill or sicken your dog but, I'd still keep it out of their diet.

Dogs musn`t eat sweets,like a human they can become very fat and their heart can stop working!

Because chocolate makes dogs really sick and if a dog eats too much chocolate the dog possibly will die.

It can give the dog a disease called worms.

cathy3305 has the best answer.Theobromide is a stimulant, and can cause tachycardia (racing heart). Caffiene is one of many theobromides.

it is toxic to dogs. if you give them enough it can kill them. white chocolate is fine to give them because it is man made. it's not real chocolate.