Male astronauts headed to Mars could thrive on this vegetarian salad

News
By Samantha Mathewson
published

Mars-bound astronauts will now enjoy the "perfect" space meal thanks to new research on nutritional, sustainable and tasty options for long-duration missions.

a colorful salad in a glass bowl
This salad made up of soybeans, poppy seeds, barley, kale, peanuts, sweet potato and sunflower seeds could be the optimal meal for men on long-term space missions. (Image credit: Adapted from ACS Food Science & Technology 2023, DOI: 10.1021/acsfoodscitech.3c00396)

Mars-bound astronauts can now enjoy the "perfect" space meal thanks to new research on nutritional, sustainable and tasty options for long-duration missions. 

Researchers studied male astronauts' specialized nutritional needs to develop more appealing, nutrient-dense options. It turns out the optimal space meal is a tasty vegetarian salad, leveraging ingredients that can be grown in space and that offer micronutrients needed to compensate for the extra calories burned, according to a statement from the American Chemical Society. Their suggested vegetarian salad includes soybeans, poppy seeds, barley, kale, peanuts, sweet potato and sunflower seeds, which was found to be the optimal meal for men on long-term space missions, according to the study.

"Astronauts in space burn more calories than humans on Earth and require extra micronutrients, such as calcium, to stay healthy during extended exposure to microgravity," according to the statement. "Additionally, future long-term missions will require growing food in a sustainable, circular way within the spacecraft or space colonies." 

Related: Future Mars astronauts may chomp on Earth's tiniest flowering plant to survive

The researchers aimed to develop a space meal that not only met male astronauts' health needs, but also tasted good and used fresh ingredients (compared to bland, prepackaged meals).  

Using a method called linear programming, the researchers assessed various combinations of fresh ingredients that would meet a male astronaut's daily nutritional needs. They also factored in the sustainability of the ingredients — those that require less fertilizer, water, time and area to grow — and recyclability to avoid added waste from inedible parts of the food grown. The computer models balanced all of these variables in 10 different food combinations to identify the optimal space meal. 

RELATED STORIES:

 —  Space diet rich in veggies and fish could boost astronaut health

 — Space food: Why Mars astronauts won't have to hold the fries (video)

 — What will astronauts on deep space missions eat? 'Neurogastronomy' may have the answer.

The vegetarian salad won out on offering the most efficient balance of maximal nutrients and minimal farming inputs. However, additional supplements are needed to provide all of the micronutrients a male astronaut needs while living and working in space, according to the statement. 

Finally, four people were invited to taste-test the researchers' new salad recipe to ensure the combination of ingredients went well together. Overall, the salad was enjoyed by all, who went back for second helpings. One tester even said they "wouldn't mind eating this all week as an astronaut," according to the statement. 

Next, the researchers plan to explore optimal space recipes for female astronauts and expand the variety of ingredients included in their computational models. 

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community@space.com.

Samantha Mathewson
Samantha Mathewson
Contributing Writer

Samantha Mathewson joined Space.com as an intern in the summer of 2016. She received a B.A. in Journalism and Environmental Science at the University of New Haven, in Connecticut. Previously, her work has been published in Nature World News. When not writing or reading about science, Samantha enjoys traveling to new places and taking photos! You can follow her on Twitter @Sam_Ashley13. 

14 Comments Comment from the forums
  • Unclear Engineer
    There are a couple of odd statements in this article.

    One is that people in weightlessness burn more calories than people in Earth's gravity. That seems counter-intuitive. Especially considering the muscle atrophy demonstrated by long-term space missions. Or, is it the exercise regime prescribed for fighting muscle atrophy that is resulting in higher caloric need than when on Earth?

    The other odd thing is the admission that " additional supplements are needed to provide all of the micronutrients a male astronaut needs while living and working in space." Probably including some protein amino acids that we humans can't metabolize for ourselves. So, is there are freeze-dried steak dinner needed for those "micronutrients" to supplement the vegetarian salad?
    Reply
  • snewsom1
    Yes, astronauts need high caloric intake due to the prescribed exercise regimen that combats muscular atrophy in microgravity environment.
    The additional supplements, I'm assuming, are for the vegetarian meal.
    The study is linked here: https://pubs.acs.org/doi/10.1021/acsfoodscitech.3c00396I'm not sure how well a tasty steak dinner would digest in space.
    Reply
  • Unclear Engineer
    I'm not sure how the tasty vegetarian meal would digest in space, either. Would the "methane production" during that digestion be captured for fuel? :rolleyes:
    Reply
  • snewsom1
    Unclear Engineer said:
    I'm not sure how the tasty vegetarian meal would digest in space, either. Would the "methane production" during that digestion be captured for fuel? :rolleyes:
    Did you see the salad that they developed?
    Reply
  • Unclear Engineer
    snewsom1 said:
    Did you see the salad that they developed?
    Yes. I noted "kale", among other things. I remembered its effect when you brought up digestion issues regarding steak.

    Don't get me wrong, I like salads. But, as part of a varied diet. Living on that salad with a "protein pill" for dessert for a whole mission to Mars and back does not sound like "optimum" to me.

    I used to quickly tire of "gorp" ("good old raisins and peanuts" mixture, actually with some M&Ms mixed in) while back packing for even as little as 2 days. I found that not mixing the ingredients , so separately eating nuts, dried fruits, chocolates and jerky of various types (usually home made) allowed me to not get disgusted with what I had to eat while out in the wilds for weeks at a time.

    Similarly, when on a sailboat in Maine for a couple of weeks, I actually got tired of eating lobster.

    I would think food taste could become an out-sized issue for the psychological well being of a crew with little to do on the way to Mars besides exercising to stay fit enough to be able to walk when they get there.
    Reply
  • snewsom1
    Steak is heavier than kale. Secondly, the salad was part of the optimal diet, not the only diet. This is only the beginning. Thirdly, had it not been for your use of the eye roll after giving your original comment the benefit of the doubt, you cemented coming across as condescending and self-centered.
    Reply
  • COLGeek
    Please stick to the topic, folks. Thank you.
    Reply
  • Unclear Engineer
    The "eye roll" emoji had to do with the indelicate image of astronauts biologically producing methane in a closed cabin space - for months at at time, and how this "optimum diet" might have some "unintended consequences".

    There are a lot of considerations for feeding astronauts on long missions. Unfortunately, the links lead to a paywall, so the only info we get about this study is what is in the article, which is basically an expansion of what is in the abstract. So, it comes across to me as "overselling" the concept of vegetarian diet.

    I think it is important to note that there is also work being done to produce "lab-grown meat" and that it might be an important factor for feeding astronauts enroute and in "continuous occupancy" situations on the Moon and Mars. See https://en.wikipedia.org/wiki/Cultured_meat .

    I think that this study probably has more to it than the article provides. At least, it does indicate that there needs to be a "closed cycle" in the food production and utilization processes. So, it is important to consider what comes out of the astronauts to be recycled into more of what went in.

    Regarding your interpretation of my attitude from my remarks, what I am really reacting to is the type of hype that headline writers put on articles like this. "Male astronauts headed to Mars could thrive on this vegetarian salad" makes it sound like male astronauts are going to just love eating it every day for months. The article says "It turns out the optimal space meal is a tasty vegetarian salad," and again that it "was found to be the optimal meal." The article's emphasis is on "the" optimum meal. That is what I am being critical about.
    Reply
  • George²
    Male astronauts
    Female astronauts also eating salads.
    Reply
  • Unclear Engineer
    Yes, there was even a previous article that said that an all-female crew was optimum for a Mars mission. That was apparently based mainly on the general data about women averaging smaller than men, so taking less space and requiring less mass of support materials to maintain their smaller metabolisms. Not very useful thinking, considering that we already have chosen fighter pilots based on physical size for generations. The logical extension of the illogical premise is that NASA should only recruit midgets for astronauts to be used on long missions.
    Reply