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How good sleep is your best defence against dementia

All this week, a pair of Alzheimer’s researchers have been sharing their expertise with Mail readers and revealing how simple lifestyle tweaks can help fend off the disease.

Today, they tell you why sleep is so important, and what you can do to make sure your brain is getting enough down-time…

Wouldn’t it be incredible to look into your future and imagine never forgetting a name, losing your keys, repeating yourself or ever having to rely on loved ones to take care of you?

Imagine being able to continue doing all the things you love well into your 70s, 80s and beyond without worrying about your mind.

Dementia has become a modern plague, the number one cause of death in the UK, and a devastating condition that now blights almost every family.

Our simple lifestyle plan provides the answer. Working as a husband-and-wife team at our clinic in the U.S., we have dedicated our careers as neurologists to finding a cure for Alzheimer’s.

Sleep is key:  Good quality rest, night after night, is critical to cognitive function and quality of life as you get older and will do more to remove toxins than any other regime or drug

Our years of studies and experience with Alzheimer’s patients have now proven that the solution lies not (yet) with some kind of silver bullet pharmacological cure, but something far more simple, inexpensive, and easily within everyone’s grasp.

We have seen hundreds of patients use our simple plan of lifestyle changes to reverse what seemed to be an imminent Alzheimer’s diagnosis, and our findings have formed the basis of our life-changing new book, The Alzheimer’s Solution, which is being serialised this week in the Daily Mail.

At the heart of our message is the fact that brain health is influenced by five main lifestyle factors: nutrition, exercise, managing stress, restorative sleep and brain training.

Sleep is key. In fact, our clinical experience has shown us again and again that good quality sleep, night after night, is critical to cognitive function and quality of life as you get older. Forget your trendy juice cleanses or detox plans; seven to eight hours of good solid sleep each night will do more to remove toxins (as well as negative thoughts and memories) than any other regime or drug.

Sleep was designed especially for the brain. This is when it drifts into a different state designed to consolidate memory and thought. Short-term memories are converted to long-term, unneeded memories are eliminated, thought processes are organised and new brain connections are built.


Missing an hour or two won’t hurt me: Studies show that skipping sleep affects your memory, your brain’s processing speed and your mood. And even if it’s only an hour or so, lost sleep is detrimental in the long term.

Your brain rests when you sleep: The brain is incredibly active during sleep as it consolidates memories, organises thought processes and clears away waste products that accumulate during the day.

Snoring is common and nothing to worry about: For some people snoring can be harmless, but for others it can be an indication of sleep apnoea

Older people don’t need as much sleep: The elderly need just as much sleep as other adults (an average of seven to eight hours per night) but struggle to get adequate sleep due to changes in the brain that occur as we age.

I can make up for lost sleep at the weekend: You can lie in and pay back some of what you missed during the week, but it’s not the same as getting regular, quality sleep all week, which is the best option for cognitive and overall health. 

This is when the brain undergoes its routine repairs, and the regeneration of neurons and their supporting cells can occur. The cocktail of chemicals released during sleep calm inflammation and bolster immunity — better sleep leads to fewer colds and immune-related disorders, and even a lower risk of cancer.

If you are keen to protect your mental and physical health into old age, and dramatically reduce your risk of Alzheimer’s, you would be well advised to take steps to improve the quality of your sleep.

Studies show that poor sleep, over time, leads to brain atrophy and shrinkage. It causes the brain’s specialised waste clearance cells to turn on themselves, pruning the very cells they should be trying to preserve, destroying healthy neurons and their connections.

The ‘brain fog’ you might get after a really bad night’s sleep is the same in early Alzheimer’s. Lack of sleep impairs your ability to function during the day, slowing your focus, your processing speed and your short-term memory.

A s everyone who has tried to function properly after a sleepless night knows, lack of sleep can blunt our responses, making us more likely to drop things and struggle with intricate or even simple actions.

In the elderly, a slight drop in sleep quality can be enough to negatively affect hand-eye co-ordination, increasing the risk of both car accidents and falls.

Sleeplessness appears to inhibit the ‘frontal lobe’ area of the brain causing the sleep deprived to make poor decisions. It certainly leaves you vulnerable to cravings which can lead to over-eating and weight gain.

Being short on sleep leads to a greater desire for high-fat foods and sweets, and triggers the release of appetite-stimulating hormones (leptin and ghrelin) which contrive to make dieting impossible. There is also a direct link between poor sleep and your body’s ability to process insulin.

These combined factors explain how people who don’t sleep enough are more likely to develop type 2 diabetes, which has been repeatedly linked to dementia and cognitive decline.

Despite all its known benefits, insufficient sleep has become a major public health concern as many of us are failing to get enough proper rest. The Sleep Council estimates that a third of Britons are getting only five to six hours of sleep a night, and 7 per cent of Britons sleep less than five hours a night.


It’s not the number of hours you spend snoring, the time you slope off to bed, or how many times you hit the snooze button on your morning alarm that count — when it comes to brain health, it’s the quality of your sleep that is really important.

We strongly recommend you think of six hours of really good quality sleep as your absolute minimum.

You should think of six hours of really good quality sleep as your absolute minimum. A chronic lack of shuteye, irrespective of how you feel and function during the day, can still inflict considerable cognitive damage over time

You should think of six hours of really good quality sleep as your absolute minimum. A chronic lack of shuteye, irrespective of how you feel and function during the day, can still inflict considerable cognitive damage over time

Most people need at least seven hours per night. More isn’t necessarily better — studies show people who regularly sleep for nine hours per night usually perform just as badly as those who sleep for less than six hours.


Studies show that between 50 and 70 per cent of the elderly don’t get the restorative sleep their brains need.

One reason is that we lose our ability to absorb daylight (through the retina of the eye) as we get older. After the age of 60, as much as 40 per cent is not absorbed properly, meaning the daylight sensors in the brain become confused, impairing their ability to set the ‘circadian clock’ which tells us when to feel sleepy and when to wake up.

Certainly, sleep studies show older people tend to stay in the initial non-restorative phases of sleep for longer and spend less time in the deeper, more restorative stages.

Night after night of lost or low-quality sleep can lead to perpetual daytime drowsiness which is known to increase the risk of dementia. 

Margaret Thatcher famously claimed that she slept only four hours a night, but in her 70s she developed dementia. We don’t know if the two were connected in her case or not, and clearly, some people can manage on far less sleep than others. But be warned — chronic lack of sleep, irrespective of how you feel and function during the day, can still inflict considerable cognitive damage over time.

The best sign that you are getting enough sleep is if you wake up every morning feeling refreshed. But if you have got into the habit of skimping on sleep and using caffeine to mask your exhaustion, you could be increasing your risk of Alzheimer’s.

The best way to remedy the situation is to draw up a personalised sleep plan which takes into account your circumstances and requirements. Work through these pages in conjunction with the free magazine we gave away in Saturday’s Mail, which forms an important part of this process (if you missed it you can get a copy by calling 0808 272 0808).

First, make an honest evaluation of how you feel when you wake up in the morning. Do you feel refreshed, or do you immediately rush for a cup of coffee or tea? And do you have energy to keep you ticking along throughout the day, or do you often feel exhausted by mid-afternoon or early evening?

Now consider which of the following steps you can take to optimise your sleep and protect your brain.


Simple sleep hygiene techniques really can transform your sleep, so you should aim to try as many as possible from this list:

1. REGULATE YOUR SLEEP SCHEDULE: Go to bed at the same time each night and get up at the same time each morning (including weekends). Keeping regular hours helps your brain know when to rest and when to be alert.


Neurologists now believe Alzheimer’s develops decades before any infuriating memory lapses and episodes of forgetfulness appear.

It’s during those apparently healthy, vibrant, younger years that the brain becomes increasingly vulnerable to a number of factors.

They include what we eat, how much we exercise, our ability to manage chronic stress, the quality of our sleep and the ways in which we challenge our cognitive abilities.

It is only much later on — often when we reach our 60s or 70s — that the brain becomes unable to compensate for our less-than-healthy lifestyle choices.

That is when we notice those first tell-tale changes in thinking and memory.

In Alzheimer’s patients, cognitive symptoms emerge only after there is so much damage that the brain’s innate resilience can no longer cope. 

2. AVOID EATING LATE AT NIGHT: When your digestive system is working to digest food, you won’t sleep as deeply and you will be more likely to wake up. We stop eating three hours before bedtime (this has eased the digestive problems that kept Dean awake).

3. AVOID COFFEE AND ALCOHOL TOO CLOSE TO BEDTIME: Caffeine can stay in your body for more than eight hours so avoid after 2 pm (this change in our lives has really helped Ayesha’s sleep). One or two glasses of wine can be relaxing, but any more will disrupt sleep cycles and could cause you to wake up in the middle of the night to use the toilet. Avoid citrus juices in the evening too as these can cause heartburn and irritate the bladder.

4. EXERCISE: Try this outdoors in the morning, and avoid exercising before sleep. Getting out into the light for a brisk morning walk will help set your circadian cycles and wake you up for the day, and exercise has been shown in many studies to increase the depth of sleep.

Walking after dinner (ideally at dusk) is also a good option because it helps your brain react to the changing light and naturally prepare for sleep. But do no exercise — especially intensive aerobic exercise — less than three hours before bedtime. It can rev you up and make dropping off to sleep difficult.

5. LIGHT TRICKS: Your brain needs bright, natural light during the day, and softer light at night.

A light box can be helpful, but use it only in the morning and have gentler, more soothing lights in your bedroom at night. And make sure that you turn off all electronic devices in the bedroom.

6. IT’S VITAL TO WIND DOWN: Avoid playing games, watching films and working on your laptop or phone in bed. It should be a place to calm the brain, not rev it up. Try reading instead to allow the mind to relax. It’s best to reserve the bedroom only for sleep and sex.

7. AVOID NAPPING: For most people, even a short daytime nap will interfere with your ability to fall asleep at night.


IF you’re relying on sleeping tablets, you could be missing out on deeper sleep stages where the brain does its most important organising and cleansing. Use the tips to help rehabilitate your sleeping patterns and decrease your dependence on medication.

8. KEEP NOISE AND SOUND OUT: Sound- and light-proof your bedroom. Both can wake you up and disrupt your sleep cycles, robbing you of the deep sleep your brain requires.


Sugary foods give your body quick energy that interferes with relaxation and sleep.

High-fat foods can cause indigestion and heartburn.

Spicy foods can irritate the stomach and also cause heartburn.

Chocolate contains sugar and caffeine, both of which can negatively affect sleep.

Adapted by Louise ATKINSON from The Alzheimer’s Solution: A Revolutionary Guide To How You Can Prevent And Reverse Memory Loss by Dr Dean Sherzai and Dr Ayesha Sherzai, published by Simon & Schuster at £14.99. To order a copy for £10.49 (offer valid until October 7) visit or call 0844 571 0640. P&P free on orders over £15.


If you’re struggling with memory or attention problems, or persistent unexplained exhaustion, ask your GP to test you for sleep apnoea. This is a very common disorder caused by the soft tissue at the back of the mouth relaxing during sleep and blocking the flow of air for a few seconds multiple times throughout the night.

Although the condition is most common in the overweight, it can affect anyone with large tongues, tonsils or adenoids; a short, thick neck; or a narrow cavity in the back of the mouth — regardless of their body weight.

When oxygen supply is cut off — even temporarily — your sleep cycle is disrupted and your brain is literally starved of oxygen. This injures neurons, in the short term contributing to chronic exhaustion, headaches and difficulty concentrating.

But in the long term, the damage incurred could increase your risk of Alzheimer’s by as much as 70 per cent. When we studied the prevalence of dementia in people diagnosed with sleep apnoea we found a significantly greater increase in dementia rates. We also found that once the disorder was diagnosed and treated, subjects were less likely to develop dementia.

Sleep apnoea is twice as likely to affect men as women. Experts believe five per cent of the UK adult population (more than 2.5 million people) are unaware they have the condition.

Yes, these puddings really are healthy!

Rich berry ‘cheesecake’

Serves 6

How good sleep is your best defence against dementia

For the base:

● 100g dried apricots, finely chopped

● 85g sunflower seeds

● 125g walnuts, finely chopped

For the topping:

● 175g cashew nuts, soaked in boiling water for 1 hour or more

● 150g frozen mixed berries, defrosted

● 1 cooked beetroot

● 1-2 tbsp date syrup

● 1 tsp vanilla extract

To serve:

● 1 handful fresh berries

● 1 sprig of mint

To make the base, first soak the dried apricots and sunflower seeds in water overnight. Then whizz them with the walnuts in a food processor, until you have a crumbly texture.

Press this into a lined 20cm cake tin, then place it in the freezer while you make the topping.

For the topping, drain the cashew nuts and add them to the food processor along with the rest of the topping ingredients. Blitz on the highest power for a couple of minutes, until you have a lovely, smooth, creamy texture.

Remove the base from the freezer and pour the topping over it, spreading out evenly. Pop it back into the freezer for another couple of hours, before transferring to the fridge for a further 2 hours.

When ready to eat, top with the fresh berries and sprig of mint.

 Nut and seed cookies

Makes about 10 cookies

How good sleep is your best defence against dementia

● 50g wholemeal flour

● 50g ground almonds

● 50g sunflower seeds

● Pinch of salt

● 1 tsp vanilla extract

● 20g xylitol sweetener

● 1 egg white

● ½ tsp baking powder

● Sesame seeds, to sprinkle

Preheat the oven to 180c/fan 160c/gas 4. In a bowl, mix together all the ingredients (except the sesame seeds) to form a sticky dough. Using a dessert spoon, divide the mixture into ten cookie shapes on a lined baking tray, leaving room for them to spread. Sprinkle each with the sesame seeds, then bake for 10 minutes until golden brown. Leave to cool and firm on the tray for 10 minutes, before transferring to a wire rack.

Chocolate and olive oil cake

Makes 8-9 slices

How good sleep is your best defence against dementia

● 2 egg whites

● 85ml olive oil

● 45g cocoa powder

● 65ml boiling water

● 250g dates, soaked in hot water

● 75g ground almonds

● 25g plain flour

● ½ tsp baking powder

● 1 tsp vanilla essence

Preheat the oven to 180c/fan 160c/gas 4. Using an electric hand whisk or a freestanding mixer, whisk together the eggs and the oil for around 5 minutes, until pale and thick.

Meanwhile, make a paste with the cocoa and boiling water and set aside.

Whizz the soaked dates in a food processor to make a date puree.

Mix the rest of the ingredients, as well as the date puree and the cocoa paste, into the egg and oil mixture and combine well.

Line a 20cm cake tin and pour in the batter.

Bake in the oven for approximately 25 minutes. It will be cooked, but still quite moist inside. Slice and serve warm or cold.

Banana bread

How good sleep is your best defence against dementia

● 1 tsp baking powder

● 1 tsp cinnamon

● 185g wholemeal plain flour

● 60g chopped nuts

● 50g sunflower seeds, plus an extra sprinkling for the topping

● Pinch sea salt

● 75ml olive oil

● 2 egg whites

● 4 overripe bananas, mashed

● 50ml water

● 1 tsp vanilla extract

● 1 tbsp date syrup (optional)

● 1 normal banana, sliced in half lengthways (for the topping)

Preheat the oven to 180c/fan 160c/gas 4. In a large bowl, combine all the dry ingredients: the baking powder, cinnamon, flour, chopped nuts, seeds and salt.

In a separate bowl, mix together the olive oil, eggs, mashed bananas, water, vanilla extract and, if using, date syrup, until well combined.

Then gradually fold the wet ingredients into the dry.

Pour the mixture into a lined loaf tin.

Top with the sliced banana and a sprinkle of sunflower seeds.

Bake for 45-55 minutes, or until a skewer comes out clean.

If the top looks like it’s browning too much, but the centre isn’t cooked, cover it with foil.

Leave to cool on a wire rack before serving.