Scientists Are Devising Clever Solutions to Feed Astronauts on Mars Space Flights
Astronaut and Expedition 64 Flight Engineer Soichi Noguchi of the Japan Aerospace Exploration Agency displays Extra Dwarf Pak Choi plants growing aboard the International Space Station. The plants were grown for the Veggie study which is exploring space agriculture as a way to sustain astronauts on future missions to the Moon or Mars.
Astronauts at the International Space Station today depend on pre-packaged, freeze-dried food, plus some fresh produce thanks to regular resupply missions. This supply chain, however, will not be available on trips further out, such as the moon or Mars. So what are astronauts on long missions going to eat?
Going by the options available now, says Christel Paille, an engineer at the European Space Agency, a lunar expedition is likely to have only dehydrated foods. “So no more fresh product, and a limited amount of already hydrated product in cans.”
For the Mars mission, the situation is a bit more complex, she says. Prepackaged food could still constitute most of their food, “but combined with [on site] production of certain food products…to get them fresh.” A Mars mission isn’t right around the corner, but scientists are currently working on solutions for how to feed those astronauts. A number of boundary-pushing efforts are now underway.
The logistics of growing plants in space, of course, are very different from Earth. There is no gravity, sunlight, or atmosphere. High levels of ionizing radiation stunt plant growth. Plus, plants take up a lot of space, something that is, ironically, at a premium up there. These and special nutritional requirements of spacefarers have given scientists some specific and challenging problems.
To study fresh food production systems, NASA runs the Vegetable Production System (Veggie) on the ISS. Deployed in 2014, Veggie has been growing salad-type plants on “plant pillows” filled with growth media, including a special clay and controlled-release fertilizer, and a passive wicking watering system. They have had some success growing leafy greens and even flowers.
"Ideally, we would like a system which has zero waste and, therefore, needs zero input, zero additional resources."
A larger farming facility run by NASA on the ISS is the Advanced Plant Habitat to study how plants grow in space. This fully-automated, closed-loop system has an environmentally controlled growth chamber and is equipped with sensors that relay real-time information about temperature, oxygen content, and moisture levels back to the ground team at Kennedy Space Center in Florida. In December 2020, the ISS crew feasted on radishes grown in the APH.
“But salad doesn’t give you any calories,” says Erik Seedhouse, a researcher at the Applied Aviation Sciences Department at Embry-Riddle Aeronautical University in Florida. “It gives you some minerals, but it doesn’t give you a lot of carbohydrates.” Seedhouse also noted in his 2020 book Life Support Systems for Humans in Space: “Integrating the growing of plants into a life support system is a fiendishly difficult enterprise.” As a case point, he referred to the ESA’s Micro-Ecological Life Support System Alternative (MELiSSA) program that has been running since 1989 to integrate growing of plants in a closed life support system such as a spacecraft.
Paille, one of the scientists running MELiSSA, says that the system aims to recycle the metabolic waste produced by crew members back into the metabolic resources required by them: “The aim is…to come [up with] a closed, sustainable system which does not [need] any logistics resupply.” MELiSSA uses microorganisms to process human excretions in order to harvest carbon dioxide and nitrate to grow plants. “Ideally, we would like a system which has zero waste and, therefore, needs zero input, zero additional resources,” Paille adds.
Microorganisms play a big role as “fuel” in food production in extreme places, including in space. Last year, researchers discovered Methylobacterium strains on the ISS, including some never-seen-before species. Kasthuri Venkateswaran of NASA’s Jet Propulsion Laboratory, one of the researchers involved in the study, says, “[The] isolation of novel microbes that help to promote the plant growth under stressful conditions is very essential… Certain bacteria can decompose complex matter into a simple nutrient [that] the plants can absorb.” These microbes, which have already adapted to space conditions—such as the absence of gravity and increased radiation—boost various plant growth processes and help withstand the harsh physical environment.
MELiSSA, says Paille, has demonstrated that it is possible to grow plants in space. “This is important information because…we didn’t know whether the space environment was affecting the biological cycle of the plant…[and of] cyanobacteria.” With the scientific and engineering aspects of a closed, self-sustaining life support system becoming clearer, she says, the next stage is to find out if it works in space. They plan to run tests recycling human urine into useful components, including those that promote plant growth.
The MELiSSA pilot plant uses rats currently, and needs to be translated for human subjects for further studies. “Demonstrating the process and well-being of a rat in terms of providing water, sufficient oxygen, and recycling sufficient carbon dioxide, in a non-stressful manner, is one thing,” Paille says, “but then, having a human in the loop [means] you also need to integrate user interfaces from the operational point of view.”
Growing food in space comes with an additional caveat that underscores its high stakes. Barbara Demmig-Adams from the Department of Ecology and Evolutionary Biology at the University of Colorado Boulder explains, “There are conditions that actually will hurt your health more than just living here on earth. And so the need for nutritious food and micronutrients is even greater for an astronaut than for [you and] me.”
Demmig-Adams, who has worked on increasing the nutritional quality of plants for long-duration spaceflight missions, also adds that there is no need to reinvent the wheel. Her work has focused on duckweed, a rather unappealingly named aquatic plant. “It is 100 percent edible, grows very fast, it’s very small, and like some other floating aquatic plants, also produces a lot of protein,” she says. “And here on Earth, studies have shown that the amount of protein you get from the same area of these floating aquatic plants is 20 times higher compared to soybeans.”
Aquatic plants also tend to grow well in microgravity: “Plants that float on water, they don’t respond to gravity, they just hug the water film… They don’t need to know what’s up and what’s down.” On top of that, she adds, “They also produce higher concentrations of really important micronutrients, antioxidants that humans need, especially under space radiation.” In fact, duckweed, when subjected to high amounts of radiation, makes nutrients called carotenoids that are crucial for fighting radiation damage. “We’ve looked at dozens and dozens of plants, and the duckweed makes more of this radiation fighter…than anything I’ve seen before.”
Despite all the scientific advances and promising leads, no one really knows what the conditions so far out in space will be and what new challenges they will bring. As Paille says, “There are known unknowns and unknown unknowns.”
One definite “known” for astronauts is that growing their food is the ideal scenario for space travel in the long term since “[taking] all your food along with you, for best part of two years, that’s a lot of space and a lot of weight,” as Seedhouse says. That said, once they land on Mars, they’d have to think about what to eat all over again. “Then you probably want to start building a greenhouse and growing food there [as well],” he adds.
And that is a whole different challenge altogether.
“Young Blood” Transfusions Are Not Ready For Primetime – Yet
A young woman donates blood.
The world of dementia research erupted into cheers when news of the first real victory in a clinical trial against Alzheimer's Disease in over a decade was revealed last October.
By connecting the circulatory systems of a young and an old mouse, the regenerative potential of the young mouse decreased, and the old mouse became healthier.
Alzheimer's treatments have been famously difficult to develop; 99 percent of the 200-plus such clinical trials since 2000 have utterly failed. Even the few slight successes have failed to produce what is called 'disease modifying' agents that really help people with the disease. This makes the success, by the midsize Spanish pharma company Grifols, worthy of special attention.
However, the specifics of the Grifols treatment, a process called plasmapheresis, are atypical for another reason - they did not give patients a small molecule or an elaborate gene therapy, but rather simply the most common component of normal human blood plasma, a protein called albumin. A large portion of the patients' normal plasma was removed, and then a sterile solution of albumin was infused back into them to keep their overall blood volume relatively constant.
So why does replacing Alzheimer's patients' plasma with albumin seem to help their brains? One theory is that the action is direct. Alzheimer's patients have low levels of serum albumin, which is needed to clear out the plaques of amyloid that slowly build up in the brain. Supplementing those patients with extra albumin boosts their ability to clear the plaques and improves brain health. However, there is also evidence suggesting that the problem may be something present in the plasma of the sick person and pulling their plasma out and replacing it with a filler, like an albumin solution, may be what creates the purported benefit.
This scientific question is the tip of an iceberg that goes far beyond Alzheimer's Disease and albumin, to a debate that has been waged on the pages of scientific journals about the secrets of using young, healthy blood to extend youth and health.
This debate started long before the Grifols data was released, in 2014 when a group of researchers at Stanford found that by connecting the circulatory systems of a young and an old mouse, the regenerative potential of the young mouse decreased, and the old mouse became healthier. There was something either present in young blood that allowed tissues to regenerate, or something present in old blood that prevented regeneration. Whatever the biological reason, the effects in the experiment were extraordinary, providing a startling boost in health in the older mouse.
After the initial findings, multiple research groups got to work trying to identify the "active factor" of regeneration (or the inhibitor of that regeneration). They soon uncovered a variety of compounds such as insulin-like growth factor 1 (IGF1), CCL11, and GDF11, but none seemed to provide all the answers researchers were hoping for, with a number of high-profile retractions based on unsound experimental practices, or inconclusive data.
Years of research later, the simplest conclusion is that the story of plasma regeneration is not simple - there isn't a switch in our blood we can flip to turn back our biological clocks. That said, these hypotheses are far from dead, and many researchers continue to explore the possibility of using the rejuvenating ability of youthful plasma to treat a variety of diseases of aging.
But the bold claims of improved vigor thanks to young blood are so far unsupported by clinical evidence.
The data remain intriguing because of the astounding results from the conjoined circulatory system experiments. The current surge in interest in studying the biology of aging is likely to produce a new crop of interesting results in the next few years. Both CCL11 and GDF11 are being researched as potential drug targets by two startups, Alkahest and Elevian, respectively.
Without clarity on a single active factor driving rejuvenation, it's tempting to try a simpler approach: taking actual blood plasma provided by young people and infusing it into elderly subjects. This is what at least one startup company, Ambrosia, is now offering in five commercial clinics across the U.S. -- for $8,000 a liter.
By using whole plasma, the idea is to sidestep our ignorance, reaping the benefits of young plasma transfusion without knowing exactly what the active factors are that make the treatment work in mice. This space has attracted both established players in the plasmapheresis field – Alkahest and Grifols have teamed up to test fractions of whole plasma in Alzheimer's and Parkinson's – but also direct-to-consumer operations like Ambrosia that just want to offer patients access to treatments without regulatory oversight.
But the bold claims of improved vigor thanks to young blood are so far unsupported by clinical evidence. We simply haven't performed trials to test whether dosing a mostly healthy person with plasma can slow down aging, at least not yet. There is some evidence that plasma replacement works in mice, yes, but those experiments are all done in very different systems than what a human receiving young plasma might experience. To date, I have not seen any plasma transfusion clinic doing young blood plasmapheresis propose a clinical trial that is anything more than a shallow advertisement for their procedures.
The efforts I have seen to perform prophylactic plasmapheresis will fail to impact societal health. Without clearly defined endpoints and proper clinical trials, we won't know whether the procedure really lowers the risk of disease or helps with conditions of aging. So even if their hypothesis is correct, the lack of strong evidence to fall back on means that the procedure will never spread beyond the fringe groups willing to take the risk. If their hypothesis is wrong, then people are paying a huge amount of money for false hope, just as they do, sadly, at the phony stem cell clinics that started popping up all through the 2000s when stem cell hype was at its peak.
Until then, prophylactic plasma transfusions will be the domain of the optimistic and the gullible.
The real progress in the field will be made slowly, using carefully defined products either directly isolated from blood or targeting a bloodborne factor, just as the serious pharma and biotech players are doing already.
The field will progress in stages, first creating and carefully testing treatments for well-defined diseases, and only then will it progress to large-scale clinical trials in relatively healthy people to look for the prevention of disease. Most of us will choose to wait for this second stage of trials before undergoing any new treatments. Until then, prophylactic plasma transfusions will be the domain of the optimistic and the gullible.
Who’s Responsible for Curbing the Teen Vaping Epidemic?
A teenage girl vaping in a park.
E-cigarettes are big business. In 2017, American consumers bought more than $250 million in vapes and juice-filled pods, and spent $1 billion in 2018. By 2023, the global market could be worth $44 billion a year.
"My nine-year-old actually knows what Juuling is. In many cases the [school] bathroom is now referred to as 'the Juuling room.'"
Investors are trying to capitalize on the phenomenal growth. In July 2018, Juul Labs, the company that owns 70 percent of the U.S. e-cigarette market share, raised $1.25 billion at a $16 billion valuation, then sold a 35 percent stake to Phillip Morris USA owner Altria Group in December. The second transaction valued the company at $38 billion. While the traditional tobacco market remains much larger, it's projected to grow at less than two percent a year, making the attractiveness of the rapidly expanding e-cigarette market obvious.
While Juul and other e-cigarette manufacturers argue that their products help adults quit smoking – and there's some research to back this narrative up – much of the growth has been driven by children and teenagers. One CDC study showed a 48 percent rise in e-cigarette use by middle schoolers and a 78 percent increase by high schoolers between 2017 and 2018, a jump from 1.5 million kids to 3.6 million. In response to the study, F.D.A. Commissioner Scott Gottlieb said, "We see clear signs that youth use of electronic cigarettes has reached an epidemic proportion."
Another study found that teenagers between 15 and 17 were 16 times more likely to use Juul than people aged 25-34. In December, Surgeon General Jerome Adams said, "My nine-year-old actually knows what Juuling is. In many cases the [school] bathroom is now referred to as 'the Juuling room.'"
And the product is seriously addictive. A single Juul pod contains as much nicotine as a pack of 20 regular cigarettes. Considering that 90 percent of smokers are addicted by 18 years old, it's clear that steps need to be taken to combat the growing epidemic.
But who should take the lead? Juul and other e-cigarette companies? The F.D.A. and other government regulators? Schools? Parents?
The Surgeon General's website has a list of earnest possible texts that parents can send to their teens to dissuade them from Juuling, like: "Hope none of your friends use e-cigarettes around you. Even breathing the cloud they exhale can expose you to nicotine and chemicals that can be dangerous to your health." While parents can attempt to police their teens, many experts believe that the primary push should come at a federal level.
The regulation battle has already begun. In September, the F.D.A. announced that Juul had 60 days to show a plan that would prevent youth from getting their hands on the product. The result was for the company to announce that it wouldn't sell flavored pods in retail stores except for tobacco, menthol, and mint; Juul also shuttered its Instagram and Facebook accounts. These regulations mirrored an F.D.A. mandate two days later that required flavored e-cigarettes to be sold in closed-off areas. "This policy will make sure the fruity flavors are no longer accessible to kids in retail sites, plan and simple," Commissioner Gottlieb said when announcing the moves. "That's where they're getting access to the e-cigs and we intend to end those sales."
"There isn't a great history of the tobacco industry acting responsibly and being able to in any way police itself."
While so far, Gottlieb – who drew concerns about conflict of interest due to his past position as a board member at e-cigarette company, Kure – has pleased anti-smoking advocates with his efforts, some observers also argue that it needs to go further. "Overall, we didn't know what to expect when a new commissioner came in, but it's been quite refreshing how much attention has been paid to the tobacco industry by the F.D.A.," Robin Koval, CEO and president of Truth Initiative, said a day after the F.D.A. announced the proposed regulations. "It's important to have a start. I certainly want to give credit for that. But we were really hoping and feel that what was announced...doesn't go far enough."
The issue is the industry's inability or unwillingness to police itself in the past. Juul, however, claims that it's now proactively working to prevent young people from taking up its product. "Juul Labs and F.D.A. share a common goal – preventing youth from initiating on nicotine," a company representative said in an email. "To paraphrase Commissioner Gottlieb, we want to be the off-ramp for adult smokers to switch from cigarettes, not an on-ramp for America's youth to initiate on nicotine. We won't be successful in our mission to serve adult smokers if we don't narrow the on-ramp... Our intent was never to have youth use Juul products. But intent is not enough, the numbers are what matter, and the numbers tell us underage use of e-cigarette products is a problem. We must solve it."
Juul argues that its products help adults quit – even offering a calculator on the website showing how much people will save – and that it didn't target youth. But studies show otherwise. Furthermore, the youth smoking prevention curriculum the company released was poorly received. "It's what Philip Morris did years ago," said Bonnie Halpern-Felsher, a professor of pediatrics at Stanford who helped author a study on the program's faults. "They aren't talking about their named product. They are talking about vapes or e-cigarettes. Youth don't consider Juuls to be vapes or e-cigarettes. [Teens] don't talk about flavors. They don't talk about marketing. They did it to look good. But if you look at what [Juul] put together, it's a pretty awful curriculum that was put together pretty quickly."
The American Lung Association gave the FDA an "F" for failing to take mint and menthol e-cigs off the market, since those flavors remain popular with teens.
Add this all up, and in the end, it's hard to see the industry being able to police itself, critics say. Neither the past examples of other tobacco companies nor the present self-imposed regulations indicate that this will succeed.
"There isn't a great history of the tobacco industry acting responsibly and being able to in any way police itself," Koval said. "That job is best left to the F.D.A., and to the states and localities in what they can regulate and legislate to protect young people."
Halpern-Felsher agreed. "I think we need independent bodies. I really don't think that a voluntary ban or a regulation on the part of the industry is a good idea, nor do I think it will work," she said. "It's pretty much the same story, of repeating itself."
Just last week, the American Association of Pediatrics issued a new policy statement calling for the F.D.A. to immediately ban the sale of e-cigarettes to anyone under age 21 and to prohibit the online sale of vaping products and solutions, among other measures. And in its annual report, the American Lung Association gave the F.D.A. an "F" for failing to take mint and menthol e-cigs off the market, since those flavors remain popular with teens.
Few, if any people involved, want more regulation from the federal government. In an ideal world, this wouldn't be necessary. But many experts agree that it is. Anything else is just blowing smoke.