Excitement from the Christmas buildup is starting to hit us. Lights around the city are twinkling and decorations are appearing in every house, and I’m sure you’re starting to think about what food you’ll have on Christmas day. But have you ever wondered why you hate sprouts? Or why you can’t help but reach for another Quality Street? Science and Tech Editor, Sarah Laptain, explains the science behind your favourite festive meal.
Sprouts: love or hate them?
Every year parents attempt to put sprouts on their children’s Christmas dinner plates. But the yearly protest against sprouts is actually down to your DNA! For some of us, sprouts taste terribly bitter, and this is due to having a certain gene. It’s thought that this gene developed when we were scavengers, and certain foods would be poisonous to us. So some people developed a genetic ‘superpower’ making some dangerous foods taste bitter.
Sprouts contain a chemical called sulphoraphane, which means they have extra sulphur in them. (You might have noticed this if you’ve overcooked them and smelt rotten eggs). If you have the gene then it causes a reaction with the sulphoraphane in the body and resulting in this bitter taste. If you don’t have the gene then you won’t taste it!
Craving for sugary snacks?
Our love of puddings and sugary snacks can be explained by looking back to when we didn’t eat as much. Sugars are carbohydrates that our bodies get energy from. So, when there wasn’t much food available and something sugary gave us a boost of energy needed, this was fantastic. This caused us to develop a sweet tooth.
However nowadays, when we have wider access to food this poses a problem. Our sugary cravings now pose more harm to our health. We no longer need the energy boost from them as our food is much more easily accessible. We have also created a lot of products containing refined sugar rather than natural sugars we find in fruit, for example. However, with a balanced diet, a few sugary snacks over Christmas won’t hurt!
Why do you feel sleepy after dinner?
The need for a nap after Christmas dinner is an all too familiar feeling, but what causes a ‘food coma’? Some scientists have suggested that an amino acid called tryptophan, found in some meats like turkey, plays a role in producing serotonin. This is a hormone that helps our bodies to feel calm or relaxed. You may also experience more production in melatonin, which is commonly found in milk. This is a hormone that makes us sleepy.
Another explanation is that consuming a high-calorie or high-fat meal means the body needs time to digest this, especially when the portions are bigger than what we normally eat. Blood is diverted away from other parts of the body, like muscles, to aid in digestion. So a post lunch walk to get the blood flowing might help you shake off the tiredness.