It is common knowledge that you should not feed dogs and cats chocolate as it is poisonous to them. This is because chocolate contains a substance called theobromine. The name theobromine comes from the Greek words theo (“god”) and broma (“food”), thus meaning “food of the gods”.
Cats and dogs metabolise this chemical very slowly, so they can easily overdose on it. Theobromine poisoning causes vomiting and diarrhoea initially, then progresses to cause hyperactivity, cardiac arrhythmias (irregular heartbeats), seizures, internal bleeding, cardiac arrest, respiratory failure and eventually death. Although cats and dogs have the same metabolism rate of theobromine, there are far less cases of cats overdosing on it as they do not have sweet taste receptors and do not particularly like the taste of chocolate.
Luckily for us, the human body can metabolise theobromine much more efficiently and we are much less likely to get theobromine poisoning (although it is still possible if you eat too much of it). Although it is weaker, theobromine behaves similarly to caffeine in the human body. It stimulates the heart to beat faster, relaxes the blood vessels, reduces blood pressure and stimulates your nervous system to decrease your tiredness and give you a “buzz”.
The effects are potent enough that there is some evidence that eating dark chocolate (which has a higher theobromine content) regularly can reduce your risk of heart disease. However, this is counterbalanced by the negative health effects of sugar and fat found in chocolate. That being said, a small amount of chocolate every now and then not only has a positive effect on your heart, but is a great medicine for your exhausted mind and soul.