As the cold, dark winter approaches, some of us envy animals that can hibernate. This long, deep rest is an example of how nature develops clever solutions to difficult problems. So how to survive a long, cold and dark period without much food and water?
But hibernation has closer connections to human history than you might think.
An article in a 1900 issue of the British Medical Journal “speaks of a strange hibernation-like state of human drowsiness.”lotkaThis was common among farmers in Pskov, Russia. Food was so scarce in this region during the winter months that the problem was solved by sleeping during the dark part of the year.
People would wake up once a day to eat a piece of bread and drink a glass of water. After a simple meal, they fell asleep again, and family members took turns keeping the fire alive. You will also find descriptions of prolonged, hibernation-like sleep during the long dark winter months in Inuit Greenland stories. In some parts of Greenland, it is dark from November to the end of January.
A 2020 study suggests that ancient ancestors of humans, called hominins, may have hibernated 400,000 years ago. Bones discovered in a cave in Spain indicate seasonal disruption in growth; This suggests that one of human ancestors may have used the same strategy as cave bears to survive long winters.
Animals and hibernation
Hibernation is deeper and more complex than normal sleep, including dramatic changes in metabolism. This long rest period combines several conditions linked to longevity, reduced caloric intake, low body temperature, and slowed metabolism.
Animals that hibernate generally live longer than other species of the same size. Recent studies using epigenetic clocks, which map activity in genes over time, suggest that hibernation slows aging in marmots and bats. So hibernation may hold important clues about how to slow down aging processes.
There are different types of aging: chronological and biological.
Chronological age is actually related to how many times the earth has revolved around the sun since the moment we were born.
It is not time itself that ages us, but “wear and tear”. Biological age measures wear and tear. It is a more comprehensive and personal measure of health than chronological age and is a better indicator of longevity. A 2023 study found that biological age changes and that temporary increases during surgery and stress, for example, are reversed once you recover.
Diseases such as cardiovascular disease, obesity, dementia and chronic kidney disease are caused by “wear and tear” that are linked to lifestyle and accumulate with age. This causes inflammation, changes in the composition of the intestinal microbiota, and increased oxidative stress. Oxidative stress is when you have too many free radicals (unbalanced atoms that damage cells) in your body.
New science based on epigenetic clocks and lessons learned from hibernating animals could help us treat patients with diseases caused by “wear and tear.” We can use drugs that can slow down aging.
For example, metformin is the first-line drug in the treatment of type 2 diabetes. It regulates inflammation, insulin sensitivity and slows down DNA damage caused by oxidative stress. There is growing evidence that it may help treat other “wear and tear” diseases such as cardiovascular disease, and long-term use of the drug may be associated with lower cognitive impairment.
Learning more about hibernation could benefit human medicine in treating traumatic brain injuries, severe blood loss, preserving muscle and bone mass, and providing better protection during organ transplantation.
A 2018 study found that mimicking hibernation conditions for storing kidney grafts from deceased donors improved their preservation. Musculoskeletal degeneration is often determined by genes, but these genes appear to be disabled in hibernating bears.
Animals and longevity
We can also learn from long-lived, non-hibernating animals such as the Greenland shark, naked mole rat, Icelandic clam, and Rougheye goby. These species have developed superior mechanisms that protect themselves against aging. Protection against inflammation, oxidative stress, and changes in proteins with age appear to be mechanisms that benefit all long-lived animals in general.
Genetic studies of rough-eyed rockfish, which can live for more than 200 years, suggest that a group of nutrients called flavonoids are associated with longevity. Citrus fruits, berries, onions, apples and parsley are rich in flavonoids, which have anti-inflammatory properties and protect against organ damage, for example, from chemicals or aging.
A 2023 study on rough-eyed rockfish found that a number of genes that may be associated with longevity were associated with flavonoid metabolism. So a long-lived fish may have something to teach us about what we should eat to live longer.
Lessons from nature and hibernating animals tell us that protecting cells, regulating metabolism, and genetic adaptations play key roles in longevity. Our lifestyle and eating habits are our best tools for mimicking some of these mechanisms.
Forty winks
There’s still a lot we don’t understand about hibernation, but we do know that normal sleep is also linked to longevity. For example, a study conducted in March 2023 showed that with quality sleep, you can add five years to the lifespan of men and two and a half years if you are a woman. Researchers defined quality sleep as sleeping seven to eight hours a day, not needing sleeping pills, and waking up feeling rested at least five days a week.
Animal sleep patterns vary widely, from bears and marmots that hibernate for eight months of the year to elephants that sleep for only two hours a day.
How elephants can grow so old while sleeping so little is still a mystery to scientists.
Figuring out how nature resolves these extremes could help scientists find new ways to improve human health.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Peter Stenvinkel receives funding for his lectures and scientific advisory boards from Astra Zeneca, Fresenius, Baxter, Novo Nordisk, Bayer, Invizius and Vifor