One of my regrets in life is not being able to speak another language with any real fluency.
I’m embarrassed by my basic French, but not embarrassed enough to put in the hard work to improve it. So I was delighted when I came across a recent study that suggests you can learn new words in your sleep.
Researchers at the University of Bern in Switzerland played volunteers a set of words in a language they did not understand, along with a translation, while they were in a deep sleep.
Then, 36 hours later, they were asked to guess whether a certain word meant an animal, a tool, or a place. They did significantly better than a control group that wasn’t played the words – amazingly proving that despite the deep sleep, they were still aware enough to learn something new.
That’s the good news. The bad news is that in order to achieve this effect, the researchers had to use very short words uttered at exactly the right time in the volunteers’ sleep cycle, so unfortunately I’m not sure this will do the trick.
But this study confirms just how much goes on in our brains while we sleep.
And it adds to growing evidence that deep sleep plays a vital role in memory and may even protect us from Alzheimer’s.
Deep sleep is one of the four main stages of our sleep cycle. It’s also known as slow-wave sleep because that’s when millions of neurons in your brain start firing together, producing large waves that slowly travel through your brain.
In deep sleep, you are most relaxed and difficult to wake up, but there is a lot going on under the surface.
Your pituitary gland in the brain begins to release more growth hormone, vital for cell growth and repair, for example.
Deep sleep also increases the production of cytokines, a type of protein that is key to helping fight infection, which is partly why a lack of deep sleep makes you more vulnerable to colds and also reduces the effectiveness of vaccines against infections like the flu.
And deep sleep is when a network of channels in your brain, known as the glymphatic system, opens up, allowing fluid to pour through it, washing away the toxic waste accumulated during the day. Which in turn can protect us from the effects of diseases like Alzheimer’s.
This was demonstrated in a fascinating new study from the University of California (UC), Berkeley, where researchers measured the brain activity of healthy 70-year-old adults while they slept. Study participants also had their brains scanned to measure levels of amyloid, a protein linked to memory loss and dementia.
The results showed that despite having large amounts of amyloid in their brains, participants who had very deep sleep performed much better on memory tests than those who had less.
Researchers believe that deep sleep may help explain why some people, despite their brains being clogged with amyloid, continue to thrive into old age, while others develop signs of dementia.
As Matthew Walker, professor of neurology at UC Berkeley and a leading sleep expert, explained, “Think of deep sleep almost as a life raft that keeps your memory afloat, instead of the memory being dragged down by the weight of Alzheimer’s disease.”
Adults typically get about one to two hours of deep sleep per night, but this decreases with age.
So how can we boost it? Besides obvious things like cutting back on alcohol and going to bed relatively early (usually the deepest sleep happens in the first half of the night, which may lend modern credence to the old adage, every hour of sleep before midnight is worth two after), you can try cut back on junk food and instead eat a high-fiber, Mediterranean-style diet.
Numerous studies have shown that people who follow a Mediterranean diet (one that is rich in nuts, olive oil, fatty fish and vegetables) have better sleep quality, while those who eat junk food tend to struggle. This includes research recently published in the journal Obesity, which compared the effect on sleep of a healthy diet with one moderately high in ultra-processed food.
Researchers at Uppsala University in Sweden randomly assigned a group of healthy young men to one approach for one week, then switched.
Although the young men slept the same length of time on both diets, when they ate the junk food, they had shallower, less restorative deep sleep, something that will become more important as they age.
Surprisingly, listening to sound can also make a difference. A few years ago I tried a headband that measures your brain activity while you sleep. As soon as the headband detects that you’re in a deep sleep, it makes a clicking sound that’s quiet enough not to wake you up.
For reasons unknown, this clicking noise, delivered at just the right moment, helps to amplify those low slow waves you get during deep sleep.
Unfortunately, it didn’t do anything for me, but a study published last year by the University Hospital of Zurich gave more positive results.
He tested a similar device on a number of people between the ages of 60 and 80 and found that it did help some get deeper sleep (although others, like me, had minimal or no response).
The researchers are currently trying to improve its performance before launching a commercial version.
But the simplest thing you can do, especially as we approach the longest day of the year, is to wear an eye mask.
Even with thick curtains, you will be exposed to a lot of bright light in the morning and last at night, and this will almost certainly disturb your sleep.
Wearing a mask works for me.
Does your face look older than your inner arm?
There are many things I love about this time of year, but the downsides include wasps, mozzies, and worst of all, ultraviolet (UV) light.
I recently finished doing a TV series on aging and one of the most impressive things I learned is how much the sun ages our skin, with up to 80 percent of facial aging being caused by UV light damage.
To see what your face would look like if you weren’t exposed to too much UV light, check parts of your body that don’t get much sun, such as your upper arm.
Of course, prevention is better than cure: you can check the strength of the sun in your area with the UV index (just search online) — it ranges from 1 to 11, but even in the 3-5 range you can still burn.
Once the damage is done, the best-researched creams contain retinol, a compound that has been shown to reduce the appearance of wrinkles by increasing the elasticity and thickness of your skin. But retinol can cause skin irritation, so start with a low concentration (0.1 percent).
No one wants to get premature wrinkles, but developing skin cancer is even worse. Although melanoma is the most feared, other forms of skin cancer, such as basal cell carcinoma (BCC), are much more common, and in the last decade the number of BCC cases has increased by 40 percent.
My wife, Claire, is one of them: now in her early 60s, she recently had two removed from her face.
Although BCCs tend to appear later in life, the damage is usually caused at a much earlier age. A sobering study by the University of Arizona, soon to be published in the journal Cancer Epidemiology, found that getting a sunburn just once every two years, at any point in your life, nearly doubles your risk of BCC. So keep an eye on that UV index.
A few years ago I became a living exhibit at the Science Museum in London when I swallowed a small camera and the pictures were projected onto a giant screen. Visitors to the museum could see live images of the inside of my stomach.
It was fantastically interesting, especially when I was eating and we were able to watch the food arrive in my stomach and slowly digest.
At the time I thought how much better it would be if I could maneuver the camera for the best images. And now researchers at George Washington University in the US have done just that, using magnets controlled by a video game-style joystick.
I look forward to trying it.
Father’s Day is tomorrow and there’s still time to buy a card or call to tell your dad how much you love him. Unfortunately mine passed away 20 years ago but I miss him dearly. And now that I’m a father myself, I can appreciate all the things you’ve done for me. He died at age 74 from, among other things, complications of type 2 diabetes. One of my greatest regrets is that I was unable to give him the advice and support that could have kept him in good health for longer . So if your parents are still alive, cherish them.