Can Gravity Make Folks Sick?

Dangerous issues occur to a human physique in zero gravity. Simply have a look at what occurs to astronauts who spend time in orbit: Bones disintegrate. Muscle mass weaken. So does immunity. “Once you go up into house,” says Saïd Mekari, who research train physiology on the College of Sherbrooke, in Canada, “it’s an accelerated mannequin of growing old.” Earthbound experiments mimicking weightlessness have revealed comparable results. Within the Nineteen Seventies, Russian scientists immersed volunteers in bathtubs coated in a big sheet of waterproof material, enabling them to drift with out being moist. In a few of these research, which lasted as much as 56 days, topics developed critical coronary heart issues and struggled to regulate their posture and leg actions.

Weightlessness hurts us as a result of our our bodies are fine-tuned to gravity as we expertise it right here on Earth. It tugs at us from beginning to loss of life, and nonetheless our intestines keep firmly coiled of their stack, blood flows upward, and our backbone is able to holding up our head. Unnatural contortions can throw issues off: Folks have died from hanging the wrong way up for too lengthy. However as a common rule, the fixed push of g-force on our physique is part of life that we not often discover.

Or at the least, that’s what scientists have all the time thought. However there’s one other chance: that gravity itself is making some folks sick. A brand new, peer-reviewed idea means that the physique’s relationship with gravity can go haywire, inflicting a dysfunction that has lengthy been a troubling thriller: irritable bowel syndrome.

It is a rogue thought that’s removed from extensively accepted, although one which at the least some specialists say can’t be dismissed outright. IBS is a quite common ailment, affecting as much as an estimated 15 p.c of individuals in the USA, and the signs may be brutal. Individuals who have IBS expertise belly ache and gasoline, really feel bloated, and sometimes have diarrhea, constipation, or each. However no precise explanation for IBS has been pinned down. There’s proof behind many competing theories, resembling early-life stress, weight loss program, and even intestine infections, however none have emerged as the only rationalization. That could be a downside for sufferers—it’s troublesome to deal with a situation while you don’t know what to focus on.

Brennan Spiegel, a gastroenterologist at Cedars-Sinai Medical Middle, in Los Angeles, has a special thought: Folks with IBS are hypersensitive to gravity on account of any variety of components—stress, weight acquire, a change within the intestine microbiome, unhealthy sleep patterns, or one other conduct or harm. The thought got here to him after watching a relative confined to a nursing-home mattress develop traditional signs of IBS. “We’re upright organisms,” he instructed me. “We’re probably not imagined to be mendacity flat for that lengthy.” The speculation, printed late final 12 months in The American Journal of Gastroenterology, is simply that, a speculation. Spiegel hasn’t carried out any experiments or affected person surveys that time to a “mismatch” in our physique’s response to gravity as the reason for IBS, although the mechanics are all based mostly in agency science. However a part of what makes the speculation so alluring is that it would embody all the different standard explanations for the illness. “It’s meant to be a brand new mind-set about outdated concepts,” he mentioned.

So precisely how would somebody’s relationship with gravity get off-kilter? Think about serotonin, a chemical that carries messages from the mind to the physique. Spiegel sees serotonin as an “anti-gravity substance” due to the position it performs in so many vital bodily capabilities influenced by g-force, resembling blood movement. Serotonin could cause blood vessels to slender, slowing circulation. It could make sure muscle tissues contract or loosen up. It’s additionally essential to digestion, serving to with bowel perform, eliminating irritating meals, and regulating how a lot we eat. With out serotonin, gravity would flip our intestines right into a “flaccid sac,” Spiegel writes. As a result of 95 p.c of the physique’s serotonin is produced within the intestine, if ranges spike or plummet from components resembling stress, then the chemical’s attainable dealing with of gravity could be thrown into chaos, affecting digestion. The outcome, he theorizes, is IBS.

Different elements of our physique that reply to gravity will also be in on the issue. We’re hardwired to react negatively to conditions wherein the pull of gravity may hurt us; stroll to the sting of a cliff and your physique will let you know one thing. The amygdala in our mind is vital to concern responses, and stress of varied sorts could cause it to enter overdrive. Spiegel thinks that when stress taxes the amygdala, an individual begins overreacting to potential threats, together with from gravity. The digestive points that make up IBS are a manifestation of that overreaction. Positive sufficient, folks with IBS have been proven to have a hyperactive amygdala.

That’s hardly something near proof. The thought that this painful and extended situation could possibly be a gravity dysfunction is a serious stretch, counting on a renegade interpretation of fundamental biology. “Folks simply assume I’m loopy,” Spiegel mentioned. Lots of his fellow medical doctors should not bought on the concept. The gravity speculation is one other in a protracted parade of unconvincing theories about IBS, Emeran Mayer, a gastroenterologist at UCLA, instructed me. He’s heard all of them: “It doesn’t exist; it’s a hysterical trait of neurotic housewives; it’s irregular electrical exercise within the colon.” He added, “I don’t assume there’s every other illness that has gone by way of these peaks of attention-grabbing new theories.”

Spiegel’s thought has clear holes. If a defective response to gravity triggers IBS, says David C. Kunkel, a gastroenterologist at UC San Diego, then you definately would anticipate to see larger charges of IBS amongst populations dwelling at sea stage versus at excessive altitudes, the place g-force is barely weaker. However that doesn’t appear to be the case: A few quarter of Peruvians dwell excessive within the mountains and most Icelanders dwell at sea stage, but each nations have excessive charges of IBS. Likewise, IBS charges seem to lower with age, “which might not be anticipated if the illness was attributable to a relentless gravitational power,” Kunkel instructed me.

Spiegel is conscious that the gravity speculation has little assist within the area and no proof. However the gravity speculation has some logic behind it. The truth that the weightlessness of house journey can drastically change the physique lends credence to the concept different shifts in our relationship to gravity might do the identical, says Declan McCole, a biomedical scientist at UC Riverside.

And the intestine could also be notably delicate to gravity adjustments. McCole has discovered that weightlessness made epithelial cells—which line the intestine and cease invaders from getting into the physique—simpler to evade. So if our inner chemistry can change in a method that makes us hypersensitive to gravity, then, to McCole, it stands to purpose that such a shift might hit the intestine onerous. He’s much less certain of whether or not that hypersensitivity exists. If it does, then why haven’t we recognized any chemical substances that assist deal with gravity, as we’ve got for concern or intercourse drive or starvation? That molecule might certainly transform serotonin, however proper now there’s no proof.

The gravity speculation actually issues solely whether it is significant for folks with IBS. And that’s not assured. Tying the very actual ache of IBS to such a fantastical thought could appear nearer to mythology than medication, leaving sufferers feeling dismissed or belittled. Or they could throw up their fingers in despair and put together for a lifetime of ache: If the immovable power of gravity is the enemy, then why trouble preventing?

But when there’s some reality to it, then the speculation might additionally present a attainable beginning place for therapies. A few of Spiegel’s solutions are already frequent, resembling weight reduction and medicines that lower serotonin, however he additionally advocates for some gravity-specific therapies. “I do discuss it with my sufferers,” Spiegel mentioned. “I like to recommend sure yoga poses; I like to recommend tilt tables.” Individuals who have IBS might balk at his extra radical concepts, resembling shifting to a better altitude or farther from the equator.

The gravity speculation might by no means be something greater than a speculation. We have now a protracted option to go earlier than really understanding whether or not the human physique can develop a hypersensitivity to gravity that may make us in poor health, or whether or not a few of us are higher geared up to deal with gravity than others. However the weight of proof is sufficient to make us assume twice earlier than ignoring the concept our physique’s relationship to gravity can go awry—together with for these of us not dealing with IBS. If gravity may contribute to IBS, why not different illnesses too? After which, why can’t it even be harnessed for good? Mekari and his colleagues not too long ago discovered that mendacity at a six-degree downward angle sped up response occasions to cognition exams—pointing to a attainable hyperlink between gravity and govt functioning. Antigravity treadmills, which assist astronauts put together for weightlessness, are being studied for the therapy of cerebral palsy, Parkinson’s illness, and sports activities accidents.

All of those unknowns about gravity can really feel haunting. Life on Earth has modified quite a bit since its first varieties appeared about 4 billion years in the past, however by way of all of it, gravity has seemingly remained fixed—maybe the only factor that connects each organism that has ever lived. What if there’s nonetheless a lot we’ve got to find out about what it’s doing to us? In any case, proper now your physique is dealing with gravity, simply because it has been for each different second of your life. Maybe it might be weirder if gravity wasn’t doing something to us over time. “Each fiber in our physique is straining to handle this power,” Spiegel mentioned. You don’t must spend 56 days in a bath to determine that out.