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The good news about Alzheimer’s is that whilst there is no real evidence you can bring back brain cells (neurons) there is lots you can do right now to make sure you don’t get the accelerated brain shrinkage that leads gradually from memory decline to Alzheimer’s.
Given that brain shrinkage starts, for many, in their 40’s, these prevention steps should be actioned now, not just later in life. In the reports included in this article you can find out what actions to take now, how to test for memory decline and what foods and supplements will help.
Key principles of an Alzheimer’s prevention diet
Eat essential fats and phospholipids
You can eat an egg a day, or six eggs a week – preferably free-range, organic and high in omega-3s. Boil, scramble or poach them, but avoid frying. Eat a tablespoon of seeds and nuts every day – the best seeds are flax, hemp, pumpkin, sunflower and sesame. (As for nuts go for what you like – Brazils, almonds, hazelnuts, cashews ... ) You get more goodness out of them by grinding them first. They’re delicious sprinkled on cereal, soups and salads.
Eat cold water, oily carnivorous fish – have a serving of herring, mackerel, salmon or sardines two or three times a week (limit tuna, unless identified as low in mercury, to three times a month). Used cold-pressed seed oils for salad dressings and other cold uses, such as drizzling on vegetables instead of butter.
Eat slow-release carbohydrates, and avoid refined ones
Eat whole foods – whole grains, lentils, beans, nuts, seeds, fresh fruit and vegetables – and avoid white, refined and over-processed foods. Snack on fresh fruit, preferably apples, pears and/or berries. Eat four servings a day or whole grains and/or pulses (rice, rye, oats, corn, quinoa or wholewheat, boiled or in a breads and pasta; and lentils, beans or chickpeas).
Dilute fruit juices and only eat dried fruit infrequently in small quantities, preferably soaked or with a small handful of nuts or seeds. Eat vitamin, mineral and antioxidant rich foods and enough protein.
Avoid harmful fats, refined carbohydrates, sugar and excess caffeine and alcohol.
Minimise your intake of fried or processed food and saturated fat from meat and dairy products. Minimise your consumption of deep-fried foods. Poach, steam or steam-fry food instead. Avoid sugar, reduce caffeine and drink alcohol in moderation Avoid adding sugar to dishes, and avoid foods and drinks with added sugar. Keep your sugar intake to a minimum, sweetening cereal or desserts with fruit.
Avoid or considerably reduce your consumption of caffeinated drinks. Don’t have more than one caffeinated drink a day. Drink alcoholic drinks infrequently, ideally wine or beer, if your homocysteine score is above nine. Otherwise, have no more than four alcoholic drinks a week.
If you’re wondering how to start making the necessary changes in your shopping, cooking and eating habits, and want help making delicious meals using the principles I outline, read my Optimum Nutrition Cookbook.
Sugar, like petrol, is dangerous stuff.
It’s the fuel your brain runs off – that’s why you can’t think straight when you haven’t eaten for hours. But if it is eaten in excess, it can literally burn your brain – and the evidence shows that this is exactly what happens in many people who develop Alzheimer’s.
Excessive amounts of sugar damage the brain partly because it forms toxic compounds called ‘Advanced Glycation End-products’, or AGEs and also because of the harmful effects of too much insulin, the hormone that is released when your blood sugar levels goes high. Think of glucose, or blood sugar, as high-octane fuel. The goal of good nutrition is to deliver ‘slow-releasing’ carbohydrates that gradually break down into pure glucose fuel, which seeps into the bloodstream and is then escorted into cells to help keep your energy high. Too much glucose overloads brain cells, called neurons, which are less capable of dealing with the overload than muscle cells. This is called glucose neurotoxicity.1 This is backed up by studies that show higher blood glucose levels are associated with less functioning brain tissue in critical areas of the brain.2
The hormone insulin escorts glucose into cells, either ensuring hungry cells get their due, or dumping excess glucose into storage. It’s a careful balancing act, and one that’s likely to go wrong if you keep eating sugary or reﬁned carbohydrates. The more you eat these the higher your insulin levels and the more often you’ll have peaks in your blood sugar levels, followed by troughs. And this seesawing will leave you tired and unable to concentrate, eventually experiencing ‘blank-mind’ episodes and fading memory. Gradually your body will become less and less responsive to its own insulin – and develop ‘insulin resistance’. Someone in the grip of insulin resistance will produce more insulin in an attempt to get a response, a condition known as hyperinsulinemia, and get rebound blood sugar lows (hypoglycemia). Eventually, they will become so insulin resistant their blood sugar levels don’t go down as they should. Type diabetes is the result.
The bitter truth about sugar
So, what’s all this got to do with preventing Alzheimer’s? The answer is everything. Being insulin resistant or diabetic, having hyperinsulinema or hypoglycemia, have all been shown to tremendously increase a person’s risk of developing Alzheimer’s or dementia.
There are probably many reasons why an upset in blood sugar control damages the brain, but one that stands out is the fact that occasional blood sugar peaks actually sugar-coat proteins, and damage them, creating damaged AGEs. A lifetime of sugar abuse, glycation (adverse interactions between glucose and proteins, for instance) and AGE creation lead to more and more artery and brain damage. The more the arteries become damaged, the worse the circulation to the brain and the less reliable the supply of nutrients becomes. So, ironically, eating too much sugar can lead to temporary glucose starvation to cells, as well as damage caused by excess glycation.
AGEs are not only bad for the brain – they also damage your skin, producing wrinkles and age spots. These damaged proteins produce 50 times the number of free radicals that non-glycated proteins do, and promote inﬂammation in the brain as well as the skin, joints and other organs.
So oxidants and AGEs constitute a double whammy for your brain. Researchers now believe that AGEs may be a player in Alzheimer’s disease because they have been found in the neuroﬁbrillary tangles that characterise the condition, and the formation of beta-amyloid plaque is signiﬁcantly accelerated by the presence of AGEs.
The glucose/Alzheimer’s link
There has been much research into the links between blood sugar and Alzheimer’s. For example, researchers at Columbia University in New York studied 683 people without dementia who were 65 years or older for ﬁve and a half years. During that time, twice as many of the participants with high insulin levels developed dementia when compared to those with normal insulin levels. Also, the people with high insulin levels had the greatest decline in memory.3 An Italian study of people free of dementia and diabetes showed that high insulin levels were strongly associated with poorer mental function.4
Meanwhile, a six-year Swedish study of 1 301 people aged 75 and over showed that those with diabetes were one and a half times more likely to develop dementia. The risk was even greater in diabetics who also had high blood pressure or heart disease.5 A number of other studies have also shown a strong association between diabetes and cognitive decline.6
Having diabetes increases dementia risk by 20%.7 Having a higher blood glucose (6.4 vs 5.5mmol/l) increases risk for dementia by 18 per cent. Diabetics with higher blood glucose levels (10.5 vz 8.9mmol/l) have a 40% increased risk.8
One of the best measures of your blood sugar control is something called glycated haemoglobin. You want to have a score below 5.5%. Researchers at the University of California, San Francisco, studied 1 983 postmenopausal women and found those with glycosylated haemoglobin levels of 7% or higher were four times more likely to develop mild cognitive impairment or dementia.9
‘We suggest the term “Type diabetes” to account for the underlying abnormalities associated with Alzheimer’s dementia-type of neuro-degeneration,’ says Suzanna delaMonte in the European Journal of Neuropharmacology after her review of the evidence last year.10
What you can do
Check your memory with the free on-line Cognitive Function Test at www.foodforthebrain.org, act accordingly and do this every year from the age of 50 since this will give you an accurate measure of your memory, and a yardstick against which to measure the benefits of the prevention steps discussed.
Up your fish intake
Eating one serving of oily fish a week is associated with halving the risk of Alzheimer’s11. Supplements of one kind of fish omega 3 fish oil, called DHA, has been shown to enhance memory in adults12 who don’t eat fish, and to prevent memory loss in those in the early stages of memory decline13. But it’s not just oily fish. The more fish you eat the better your memory test performance. Fish is also an excellent source of vitamins B1214, D and choline, all essential for the brain. Chia and flax seeds have the most omega 3. As well as eating these foods I’d recommend you aim to supplement about 250mg of DHA a day. If your supplement contains DPA this converts readily to DHA so add to the DHA level and aim for a total of 250mg.
The studies above used around 1 000 mg a day, which is what I’d recommend if you don’t score well on the Cognitive Function Test. This would mean adding a 1 000 mg fish oil capsule to your daily supplements, as well as eating oily fish at least three times a week.
Up your fruit and veg
Eat at least six servings of brightly coloured vegetables and berries a day. Half a plate of vegetables counts as two servings. A glass of good quality red wine counts as one. The more fruit and vegetables you eat the lower is your risk of cognitive decline15 with vegetables being particularly protective.16 The best kinds of vegetables are carrots, cauliflower, broccoli, Brussels sprouts, cabbage, spinach, mushrooms and the best fruits are berries, especially blueberries and strawberries17.
Flavonoids and polyphenols, found not only in fruit and vegetables, but also in tea, red wine and dark chocolate, are associated with preserving memory.18 The most protective effect is found eating six servings (500g) a day of fruit and vegetables.16 Supplementing both vitamin C (1g) and vitamin E combined is associated with halving the risk of Alzheimer’s disease.19
Eat a Low GL Diet
Follow a low GL diet, with slow-releasing ‘whole’ carbohydrates (such as wholegrain bread or pasta and oat cakes), keeping you blood sugar levels down, which also means you make less insulin and you preserve your memory20. Eating white bread is associated with a poorer cognitive test performance, whereas high fibre bread is associated with better performance. Eating carbohydrate foods with protein, for example brown rice with fish, or porridge oats with seeds further reduces the glycemic load (GL) of a meal. Best fruits in this respect are berries, cherries and plums while too many grapes, raisins or banana are high GL. These kind of foods are consistent with a Mediterranean diet which has also been shown to reduce risk.21
Supplement B vitamins – Check your homocysteine
Supplement vitamin B6 (20 mg), B12 (10 mcg) and folic acid (200 mcg) as a sensible precaution. But do check your homocysteine level to find out how much you need. If above 10 mcmol/l supplement high dose B6 (20 mg), folic acid (800 mcg) and B12 (500 mcg) preferably in a supplement that also provides zinc and TMG.
Having a higher intake and blood level of vitamin B12 and folic acid is associated with a quarter of the risk of developing Alzheimer’s.22 Vitamin B6, B12 and folic acid, especially in combination, lower blood levels of homocysteine, which is a key predictor of risk.23
B12 absorption can greatly worsen with age, and is inhibited by the diabetes drug metformin16, and antacid ‘proton-pump inhibitor (PPI) medication17. If you are taking these be sure your GP checks your homocysteine level.
Limit coffee – Green tea is better
While there is inconsistent evidence linking coffee with more or less risk, drinking lots of coffee both raises homocysteine levels28 and promotes the excretion of protective B vitamins29.
Green tea, on the other hand, is associated with a lower risk of cognitive impairment.31 My advice is to limit coffee to one a day and drink tea, ideally green, instead. The occasional or daily glass of red wine is also likely to lower your risk.
Keep physically, mentally and socially active
Keeping fit, learning new things, stimulating your mind, and staying in touch with friends and family all helps to reduce your risk. There may also be a benefit in exercises that require more mind-body coordination, such as t’ai chi or yoga, and exercising outdoors – we make vitamin D in the presence of sunlight. These activities also help to reduce stress, which is another prevention step in the right direction as is keeping your blood pressure down.
A list of references is available from the Natural Medicine office. Tel: 021 880 1444
He, together with his team, carried out Britain’s biggest-ever health and diet survey, the 100% Health Survey, which has now been completed by over 60 000 people. His book, The 10 Secrets of 100% Healthy People, portrays the fascinating insights provided by the survey and his 30 years study of good health and how to achieve it.
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