What Do Astronauts Eat? Which Essential Nutrients Make It to Outer Space?
What do astronauts eat? Is it some sort of nutritional toothpaste or protein cube? Are there traditional kitchens in space modules? How far away are we from a Star Trek-style food replicator?
While it's not yet reached the level of science fiction, space food has come a long way from where it started, not just for the sake of the crew members' taste buds, but for their health and the necessity of maintaining earthly levels of muscle and bone mass in zero gravity conditions. Our own Dr. Robert Wolfe, who developed an amino acid supplement for civilian consumer use, has contributed to this very NASA research in the sphere of muscle preservation and amino acid supplementation in space. We have the details below on what astronauts eat, why certain nutrients are so essential, and what that tells us about the health of all humankind.
What's on the Menu for NASA Astronauts?
When the U.S. space program first began, astronaut food was not so great. The same way that food packages for our soldiers have evolved into more nutritious fare (and now come in self-heating food containers), NASA space food has come a long way, and the same is true for the European Space Agency.
Astronauts who first braved the final frontier ate freeze-dried powder, concentrated food cubes, and aluminum tubes full of liquid gels. There was no real variety of flavor choice either, though one of the first evolutions of space food was to provide taste options like applesauce, butterscotch pudding, and shrimp cocktail as soon as the packaging improved enough for freeze-dried preservation.
Hot water was available on space missions by the 1960s with the Gemini and Apollo programs. This advancement enabled astronauts to rehydrate their food and enjoy easier access to hot meals. By the 1970s, the food pouches included up to 72 different flavors, and today the technology is even more advanced, allowing astronauts to better enjoy their food during long periods in zero gravity.
Taste isn't the only factor to consider, of course: priority one is to make sure astronauts are as healthy as possible. Here are a few of the factors at play when it comes to feeding men and women who aren't Earth-bound.
1. Nutrient Needs
There can be no cutting-corners in space: astronauts need 100% of their daily required nutrients and minerals from the food they eat. That means that not only do scientists and nutritionists have to figure out a way to transport and preserve the various foods we enjoy so casually on Earth, but they also have to take into account which nutrients astronauts need different levels of, like vitamin D (which we get from spending time in sunlight), sodium, and iron. Astronauts need low-iron foods because they're working with fewer red blood cells while in space, but vitamin D and sodium are needed in higher levels to support bone density. There are no sunny days on a space station, and a lack vitamin D can lead to dangerous bone loss or spaceflight osteopenia.
Food selection also takes into account storage requirements, packaging necessities, and sensory impact (smelly food on a space station, where you absolutely cannot open a window to the vacuum of space, is not good for astronaut morale).
2. Astronaut Feedback
While the mission at hand is the priority of the astronauts sent into space, the main mission of so many other minds on the ground is astronaut health, well-being, and stamina. That means that not only can astronauts provide feedback on preferences they have for the packaged meals, but they are also allowed "bonus foods" they can bring along independently, a choice that garnered a lot of public interest and attention in 2013 when Canadian astronaut Chris Hadfield crowd-sourced ideas for what foods he could bring along for a 6-month stay on the International Space Station (ISS) with fellow astronauts, American Thomas Marshburn and Russian Roman Romanenko.
The requirements for bonus foods include having a long shelf life and being appropriate for space travel: nothing that can explode, nothing too wet or messy, and, of course, nothing too smelly for the sake of international (and interstellar) cooperation.
Hadfield ended up taking along foods like dried apple pieces, chocolate, orange zest cookies, jerky, and maple syrup in a tube, all sourced from his Canadian homeland. Those were treats on top of the menu selection each astronaut gets to choose before departing: they can have the same thing every day, or plan for a 7-day meal cycle so no one food gets too dull.
3. Future Hydroponics
NASA researchers are still looking for ways to grow fresh food in space. With an 18-month mission to Mars in the works, the Advance Food System division of NASA has already chosen 10 crops that would provide the nutrition needs for those in space. Those foods are:
- Bell peppers
- Fresh herbs
- Green onions
Their hopes are to one day get rice, peanuts, beans, wheat, and potatoes growing in space too (you may have seen Matt Damon on the big screen farming potatoes in The Martian, but as of yet that is science fiction still just beyond our reach).
What Do Astronauts Eat? A Space Menu
According to NASA's own website, astronauts have choices for three meals a day: breakfast, lunch, and dinner, with the calories provided adjusted to the needs and size of each astronaut. The types of food range from fresh fruits (for the first few days before they spoil), nuts (including peanut butter), meats like seafood, chicken, and beef, desserts like brownies and candy, plus beverages like lemonade, fruit punch, orange juice, coffee, and tea. While they can't yet grow rice in space, they can be sent up with it and other foods like cereals, mushrooms, flour tortillas, bread rolls, granola bars, scrambled eggs, and mac and cheese.
Long-term storage of food in space means that a lot of the food items are rehydratable: dried until the astronauts add water generated by the station's fuel cells. Many items are thermostabilized or heat-treated to destroy any enzymes or microorganisms that might cause the food to spoil. Packaged fish, fruit, and irradiated meat can be transported into space this way, along with more complex packaged meals like casseroles. Beverages all come in powdered form until they are mixed with water at the time of consumption. Condiments like mustard, mayo, ketchup, and hot sauce (strangely enough) stay exactly the same, and can be sent to space in their commercially available packets.
1. Ham Salad Sandwich
This is actually the first meal that American astronauts had on the moon. Not unlike the chicken, egg, or tuna salad sandwiches we enjoy on Earth, Neil Armstrong and Buzz Aldrin ate these sandwiches along with "fortified fruit strips" and rehydratable drinks on the very first lunar excursion. Time magazine states that the Apollo 11 mission ate four meals in total on the moon's surface, and that their resulting waste is still left behind today in the lunar module.
2. Tubes of Applesauce
Another first here: the first food eaten in space by an American (John Glenn), and this one confirms a lot of what people assume about food during space travel: it's in a tube, thick enough so it won't float away from you in a microgravity environment. Just like squeezing out toothpaste, the first American in space squeezed applesauce out of an aluminum tube during the Mercury space mission of 1962.
3. Rehydratable Mac and Cheese
The instant macaroni and cheese you pour hot water over isn't wholly unlike the kind they eat in space. The same goes for other dishes besides this standard American comfort food, like chicken and rice, dried soups, and instant mashed potatoes. Astronauts can even eat breakfast cereals this way, which come fortified with essential nutrients and packaged with dry milk and sugar for that familiar taste of home.
4. Irradiated Lunch Meat
"Irradiated" sounds like this food just came out of Chernobyl, but in fact most of what astronauts eat is irradiated (not radioactive) to eliminate any traces of insect activity or microorganisms that might otherwise spoil or damage the food before the astronauts can partake. It happens to food on Earth too, especially seafoods and other animal products that have a high potential to spoil when preserved for a long period of time, but it's also done to fresh fruits and seasoning herbs too. It's all FDA- and NASA-approved for safety.
5. Cubed Foods (Like Bacon)
Here's another menu item in line with what the imagination expects: cubed food was part of a space diet from the very beginning, and that still remains true in some instances. In the early days, these bite-sized cubes were rather unappetizing. Let's just say that along with the hassle of squeezing tubes and dealing with the crumbs from freeze-dried foods, which might interrupt instrument functioning on the vessel, the cubes were not a crowd favorite. (To reduce crumbs, sandwiches and food cubes like cookies used to be coated in gelatin, which makes spaceflight sound less glamorous than ever.)
One of those cubed foods was bacon squares. That's right: compressed bacon that was enjoyed regularly by the Apollo 7 astronauts according to Popular Science—they were much the favorite over bacon bars, most of which returned to Earth when the mission was complete. Now the nearest approximation to bacon cubes on the International Space Station are some freeze-dried sausage patties, not unlike the kind many people keep in their home freezers.
The variety of food has since expanded to over 200 menu items, but some of them (like chicken dishes) are still cut up into bite-sized chunks: no one has time to carve a turkey in space.
6. Shrimp Cocktail and Hot Sauce
The most popular dish on the International Space Station across the nations is shrimp cocktail. With a powdered sauce infused with horseradish, for whatever reason, among the hundreds of dishes from Russia, the United States, and Japan, shrimp cocktail is the most highly preferred.
Maybe it has something to do with that spicy sauce, because another people-pleaser in space is hot sauce. Even for those star-walkers who don't like hot sauce back home, hot sauce in space not only livens up otherwise bland dishes, but some astronauts say that taste doesn't work the same way in space, and that all of the food tastes bland to them, including their usual favorites.
Likewise hot sauce also works practically to help clear the nasal passages: if you get a stuffed up head in space, there's no fresh air to be found. That "stuffiness" may be what accounts for an inability to taste most flavors and why hot sauce has become a favorite for many.
7. Liquid Spices
Without gravity's assistance, you can just pepper or salt your food in space like you would on the ground. That leads to items like liquid salt and pepper, so that the spices are actually applied directly to the food instead of floating off to get grit in the space station's sensitive machines or to end up in a fellow astronaut's nose or eyes. Salt is applied in the form of salt water, while pepper is suspended in an oil.
8. Powdered Liquids
All the drinks in space start as powders, including orange juice, apple cider, coffee, and tea. The powder is pre-loaded in a foil laminate package. So the dusty particles cannot escape, astronauts must secure the water source to a connector on the packet to add liquid. After that, they drink it from a straw (sort of like a Capri-Sun, but with way more at stake).
Not all foods work in powdered forms however. Ground control used to send people to space with freeze-dried astronaut ice cream, but it's no longer included on the International Space Station. The astronauts disliked it too much due to its crumbly, chalky texture, which felt uncomfortable against their teeth and left an unpleasant film on the tongue.
9. Tortilla Wraps
Instead of bread (another crumby entity) or lettuce (which wilts), NASA now uses tortillas to make sandwich wraps for space travel. They're partially dehydrated, and can last up to 18 months on the ISS. It was only thanks to Mexican payload specialist Rodolfo Neri Vela that tortillas were introduced to the space food system, where they are now invaluable.
The ability to last for long periods of time is essential due to the inherent delays in space travel. Fresh fruit and veggies sent to space have to be kept in a special fresh food locker that is resupplied a little more frequently by a space shuttle, but when the supply comes in they have to be eaten quickly before they spoil and rot.
10. Thermostabilized Fish
Remember the irradiated lunch meat from before? Thermostabilization is another type of heat treatment applied to food that may have destructive microorganisms. It's the same tech used on Earth before canning our seafood, be it tuna, salmon, or sardines. While fish is one of the smellier items allowed on the ISS, it's nevertheless too important a source of protein and nutrients like omega-3 fatty acids to do without.
What the NASA Diet Tells Us About Human Nutrition
It is imperative that the food sent up with our astronauts helps them keep muscle mass in space, and the same goes for bone density. The more scientists learn about what space does to the human body and how to protect astronauts from damage, the more the world learns about overall human health.
For example, studies on astronaut Scott Kelly and his twin brother reveal how leaving the bonds of Earth impacts the human body, and suggests how long we as a species can withstand the weight loss of zero gravity. Space travel biology provides data on human biology we may never have known otherwise, and here's how it can positively impact you.
- Bone strength: While working to prevent bone loss during spaceflight, scientists are discovering better ways to protect bone loss in the ill and elderly here on Earth.
- Eye function: Astronauts sometimes experience impaired vision due to spaceflight, and NASA's research into understanding and preventing this may help prevent damage to the human eye and vision for those on the ground.
- Muscle health: NASA has studied muscle inactivity to determine what level of muscle atrophy or wasting may impact astronauts. Studies like these led to the development of Amino Co.'s balanced essential amino acid (EAA) supplement to prevent muscle loss for those injured, on bed rest, or in space.
New muscle growth cannot happen without the proper balance of all nine essential amino acids. Discovering that ideal ratio was the first step, and developing the formula was the next. Now there is a supplement appropriate for people under extreme conditions to preserve the muscle they have and replace the muscle that is lost with new growth, reversing space- or age-related muscle loss. In that sense, space exploration and experimentation today is a lot like Star Trek: in many ways exploring space involves finding out what it means to be human.
The Space Between
As humans we should all be proud of the advances we've made in space travel, and just how far we've gone as a species. Likewise we here at the Amino Co. are proud to be associated with the important work Dr. Wolfe has done, and the findings he's brought back from NASA that are now accessible to anyone looking to preserve or build muscle, even under circumstances that are literally out of this world. Explore the available formulas, and help your body become space-strong.