The genes that allow some people to sleep as little as four hours each night may also play a role in preventing dementia, scientists say.
A mouse study found that two genetic mutations carried by elite sleepers slow the accumulation of toxic proteins in the brain, a hallmark of memory-depriving disease.
The link between sleep and dementia has been established for many years, and studies have shown that poor sleep quality or too little eye-closing increases the risk.
Toxins are removed from the brain and other parts of the body during sleep, which keeps our mind and muscles rejuvenated the next day.
Sleep researchers at the University of California, San Francisco believe that the genes found in 5% of people allow people to do this more efficiently.
For most people, doctors recommend seven to nine hours a day, with eight considered optimal. But some people, dubbed “elite sleepers,” can reap the benefits in as little as four hours.
It has been suggested that known carriers of the genes may be former US President Donald Trump, who is known to sleep only four to five hours a night.
Elon Musk and Dwayne “The Rock” Johnson also claim to get three to six hours of sleep each night.
Former U.S. President Donald Trump (pictured at a rally in South Carolina on March 12) has previously claimed to get only four to five hours of sleep.
Billionaire Tesla founder Elon Musk, notorious for his bizarre social media ranting, sleeps only six hours a night. Musk pictured during a media tour of the Tesla Gigafactory in Nevada.
Dwayne “The Rock” Johnson, pictured at the Super Bowl in Los Angeles last month, sticks to a sleep schedule that makes most people want to nap: The actor gets only three to five hours of sleep each night.
WHAT IS ALZHEIMER?
Alzheimer’s disease is a progressive degenerative brain disease in which the accumulation of abnormal proteins leads to the death of nerve cells.
This destroys the transmitters that carry messages and causes the brain to shrink.
More than 5 million people suffer from the disease in the US, where it is the sixth leading cause of death, and more than 1 million Brits have it.
WHAT’S GOING ON?
When brain cells die, the functions they provide are lost.
This includes memory, orientation, and the ability to think and reason.
The progress of the disease is slow and gradual.
On average, patients live five to seven years after diagnosis, but some can live ten to 15 years.
EARLY SYMPTOMS:
- Loss of short term memory
- Disorientation
- Behavioral changes
- mood swings
- Difficulties with money or a phone call
RECENT SYMPTOMS:
- Severe memory loss, forgetting close family members, familiar objects or places
- Anxiety and frustration due to the inability to make sense of the world, which leads to aggressive behavior.
- Eventually lose the ability to walk
- May have problems with food
- Most will eventually need round-the-clock care.
Source: Alzheimer’s Association.
Senior author of the study, Professor Ying-Hui Fu, an expert in neuroscience, said she hopes their findings could lead to the development of new drugs to help patients with brain disorders have more restful sleep and prevent conditions like dementia.
“Many parts of your brain have to work together to get you to sleep and wake up,” she said. “When these parts of the brain are damaged, it becomes harder to fall asleep or get quality sleep.
“This work opens the door to new insights into how to delay and possibly prevent many diseases.”
Professor Fu and her team in California are studying the genetics of “elite sleepers”.
Previously, they identified five genes found in humans that play a role in elite sleep – four to six hours a night without any clear negative health effects.
In their latest experiment, they tested two of these gene mutations, named DEC2-P384R and Npsr1-Y206H.
They bred two groups of rodents with a predisposition to Alzheimer’s disease, the most common form of dementia, to carry one of these genes.
Analyzing the brains of mice three and six months later, they found that rodents with short-sleep genes had fewer abnormal proteins thought to play a role in the development of Alzheimer’s compared to controls.
Publishing their findings in the journal iScience, they said they had demonstrated that genes can slow the progression of a disease.
Dementia is one of the leading causes of death in the UK and charities estimate that roughly 900,000 people in the UK and 5 million in the US are living with the disorder, and that number is growing every year as we live longer.
Fellow senior author neuroscientist Dr. Louis Ptacek added that their study added to their previous work by questioning the “dogma” that everyone needs eight hours of sleep a night.
“There is a dogma in this field that everyone needs eight hours of sleep, but our work to date confirms that the amount of sleep people need depends on genetics,” he said.
“Think of it as analogous to height; There is no ideal amount of growth, each person is individual. We have shown that the situation is similar for sleep.”
Sleep deprivation has been linked to a number of other conditions, such as obesity, heart disease, high blood pressure, and diabetes.
However, experts debate whether this amount or quality of sleep is a key factor in health.
Prof. Fu and Dr. Ptacek say their study showing that “elite sleepers” can achieve the same restorative results in less time shows that sleep quality is critical.
So far, the researchers have identified five genes associated with “elite sleep” that run in families, but add that there are many more yet to be discovered.
While they estimate it could take a decade to develop new treatments based on their research, they stress that one of the genes they have identified could already be targeted to existing drugs.
This means that drugs can be repurposed to help prevent dementia, which is faster than developing a new drug from scratch.
A number of celebrities, politicians and entrepreneurs swear by getting only four to six hours of sleep a night, and some attribute their success to this.
Former US President Trump and his predecessor, Barack Obama, had famously short sleep cycles during their tenures, roughly four to five hours.
It is not known if any of these famous individuals have “elite sleeper” genes or if they force themselves into a short sleep cycle instead.
There is currently no cure for dementia, but a number of drugs are used to slow the progression of the disease, and are more effective the earlier it is found.
Experts are warning of a potential global dementia time bomb, and 153 million people worldwide are projected to live with the disease for decades.