Top login menu

Murray Edwards College
University of Cambridge

School Winner: Why eat chocolate?

  • Home
  • Main page content

    06 Oct

    Science fact

    Elephants rarely get cancer: less than 5% of captive elephants die of cancer, compared to 20% of humans. Elephant genomes have at least 20 copies of the tumour suppressor, p53, which may explain their low cancer rates relative to humans, who have only one copy. 

    Find out more

    georgia-bohan-wirral-grammar-school-for-girls1c-georgi-bohan-photo As a nation, Great Britain is one of the highest consumers of chocolate in the world. On average a British person consumes 11kg of chocolate each year, the equivalent of three bars a week; so why do we eat so much chocolate? As well as its sweet taste and creamy texture, chocolate contains a compound called theobromine which is thought to be another cgeorgi-bohan-imageontributing factor to chocolate's popularity . Theobromine is a fairly simple organic compound with the formula C7H8N4O2, it is a bitter tasting alkaloid and comes from the cocoa plant. Theobromine has some similar effects on the body as caffeine, since the two substances have an extremely similar structure. For example, theobromine can reduce tiredness and increase alertness. It is also a cough suppressant and can help reduce the symptoms of asthma.

    Although the effects of theobromine on humans are mild, it can have more serious effects on some animals. Dogs for example are unable to break down theobromine in the same way that humans can, so it can therefore have a toxic effect.

    The darker the chocolate, the higher the concentration of theobromine. This means that a small dog could be killed by eating just 50 grams of dark chocolate. Cats can also be effected in a similar way, however they don't have the sweet  taste receptors that dogs have so are less likely to consume chocolate. Humans have three times the resistance to theobromine than dogs, meaning that a human would have to consume over 5kg of milk chocolate at once (over 100 Cadbury Dairy Milk bars) for the effects to be fatal. Humans are more likely to be effected by the fat, calorie and sugar content of chocolate as opposed to theobromine poisoning. Per 100 grams, dark chocolate has about 600 calories and 43g of fat, 25g of which is saturated fat. Sugar is also a contributing factor to tooth decay and obesity. However chocolate does have some benefits, as it can improve cardiovascular health. This is because chocolate, especially dark chocolate,  contains flavonoids which can help lower blood pressure and improve cholesterol levels. Although these benefits can be counteracted by the fat and calories which can cause weight gain. Despite the health implications of chocolate, its consumption has continued to grow in previous years and remains a popular treat amongst many. However next time you indulge into your favourite bar, spare a thought for your canine companions who are missing out on the delicious treat.

    Georgi Bohan
    "My name is Georgia and I am currently in Year 13 studying Chemistry, Maths and French A Levels at Wirral Grammar School for Girls. Next year I am hoping to study Chemistry at University."