In the movie ‘The Martian’, Mark Watney was left stranded on Mars and survived for months by growing potatoes in Martian soil mixed with human waste as fertiliser. Thankfully, on the International Space Station the situation is not quite so dire, but food is critical for our survival nonetheless! Normally, at least six months worth of food for a crew of six is maintained onboard the space station. Of course, none of this is fresh, nor can it be refrigerated or frozen. The food that we eat is either irradiated, rehydrated, canned or dried goods. Our ‘kitchen’ consists of an electrical food heater and a hot water dispenser…and that’s pretty much it.
Feeding astronauts is not as straightforward as you might think. Of course, we require sufficient calories, vitamins, minerals and other nutrients to enable the human body to function normally. However, the human body undergoes a few changes in microgravity and we have to consider this in our diet. For example, too much salt can exacerbate the loss of bone density that astronauts suffer from in space and much of our food can taste a bit bland as a result. Normally, astronauts take a vitamin D supplement each day to help counter the effect of being isolated from the sun’s rays for six months. Additionally, ‘space food’ must be lightweight and have a long shelf life. Our standard Space Station menu takes all of these factors into consideration and does a pretty good job…but it is a bit repetitive and you can often tell ‘tastiness’ was not highest on the list of priorities!
Thankfully, this is not the whole story – we get ‘bonus’ food! Although this sounds like we’ve won some sort of competition – bonus food actually accounts for around 10% of our calculated calorific intake and so it is vital to our wellbeing. Astronauts are allowed to choose their own bonus food as long as it does not cost more than the standard food it replaces. When I was asked what bonus food I would like to take with me, I could have picked existing, commercial products, but it seemed like a much better idea to offer this up as a challenge to kids to get them thinking about healthy eating, nutrition and the problems associated with getting food into space. Oh – and I added one other very important criteria: tastiness!
The Great British Space Dinner competition was a huge success and engaged 2000 students from both primary and secondary schools from all over the UK. Of course, every competition requires a prize so it was decided that the winners would get to develop their menu with a celebrity chef to be used as inspiration for the actual meals that would be sent up into space as my bonus food. So, 10% of my diet was now in the hands of schoolkids…and they did not disappoint. The students had put so much thought and effort into their menus that it was hard to pick just three winners as was originally intended – so instead we ended up with five winning teams! Each menu had been carefully thought out as something fun, healthy, nutritious, tasty and with a hint of Britishness to give morale a boost and to help keep me connected with home whilst in space.
Having been on the International Space Station for over three months now, I can testify to the increased importance of the role that food plays in space. Our sense of smell is diminished in space because all the fluid shifts up to our chest and head, giving us a ‘puffy face’ look and often a feeling of nasal congestion. Our circadian rhythm can struggle with the sixteen day/night cycles we experience every 24 hours and this can also affect our appetite. We exercise for two hours every day and so require a good amount of calories but often the food portions are small and so we have to be careful to monitor that we are eating a sufficient quantity and getting a balanced diet. Most importantly, living in a confined, artificial environment with a recycled atmosphere we feel the isolation from planet Earth – suddenly that bonus food takes on a whole new role in terms of morale and psychological wellbeing.
So, to all the students who took part in the Great British Space Dinner challenge I would like to say a very special thank you from here in space for taking part and for developing such important fuel for my mission. Remember that healthy eating, exercise and a well- balanced diet is just as important for life on Earth as it is in space.