Eating well can slow down Alzheimer's onset
Dr Neal Barnard says diet and exercise could help fight Alzheimer's disease
FOR anyone with a friend or family member suffering from a degenerative brain disease, you know firsthand how cruel these can be.
With greater understanding and awareness of these conditions, hopefully society will treat sufferers with greater compassion as the disease progresses.
But wouldn't it be empowering and encouraging to know there is something you can do to help slow or prevent the onset of Alzheimer's? Instead of it being an almost inevitable outcome if it runs in your family.
The good news is that Dr Neal Barnard, a world authority on nutrition and neurology, has published his research on the correlations between diet and preventing Alzheimer's disease: the foods we should avoid and the good foods and nutrients we should have daily. Plus extra advice of exercise, mental stimulation and adequate sleep.
In the research, he highlights many foods that we know affect cancer, heart disease and Type 2 diabetes. I had the pleasure of interviewing Dr Barnard, who gave a comprehensive summary plus answers to pertinent questions.
The baddies – these foods need to be severely reduced and in some cases eliminated altogether:
Saturated fats – Found in meats and dairy products, appear to encourage the production of beta-amyloid plaques within the brain. The Chicago Health and Ageing Study reported in the Archives of Neurology in 2003 that people consuming the most saturated fat had more than triple the risk of developing Alzheimer's disease than those who generally avoided these.
Trans fats – Found in processed foods such as doughnuts and pastries, have been shown to increase Alzheimer's risk more than five-fold.
These 'bad fats' raise cholesterol levels and apparently increase production of the beta-amyloid protein that collects in plaques in the brain as Alzheimer's disease begins.
If you see the words 'hydrogenated' or 'partially hydrogenated' on a package, it contains trans fats.
Excess Iron – While we need iron to make the haemoglobin that carries oxygen in the bloodstream, excess iron can build up in the brain, sparking the production of damaging free radicals. Sources of excess iron include cast-iron cookware, meats and iron supplements.
Q: You recommend not taking supplements with iron, but how does this apply to pregnant women, who are advised to take extra iron and it is present in most pregnancy vitamin supplements?
Dr Barnard: For pregnant women, like everyone else, iron supplementation should be given only if it is medically needed, not simply as a matter of routine. During pregnancy, it is easy to test iron status and to give iron if needed.
Excess Copper – The body needs traces of copper to make enzymes. In excess, copper impairs cognition, even in mid-adulthood, and ends up in the plaques of Alzheimer's disease. It comes from copper pipes and nutritional supplements.
Aluminium – Aluminium's role in the brain remains controversial. However, because it has been found in the brains of Alzheimer's patients, it pays to err on the side of caution. Avoid uncoated aluminium cookware and read labels when buying baking powder, antacids and processed foods.
Q: We now know of the health benefits of eating fish but are urged to limit the amount of certain fish we eat, such as tuna, due to the excess mercury present in the meat. Is there a correlation between mercury and Alzheimer's?
Dr Barnard: Mecury is linked to serious brain damage of other types, but not specifically to Alzheimer's disease. As you have noted, many species of fish accumulate mercury.
For that reason, among others, I recommend skipping fish and getting omega-3 fatty acids from plant sources, such as green leafy vegetables. The traces of omega-3 they provide are especially healthful.
Protective Brain Foods
• Nuts and seeds are rich in vitamin E, which has been shown to help prevent Alzheimer's. Especially good sources are almonds, walnuts, pine nuts hazelnuts, pecans, pistachios, sunflower seeds, sesame seeds, and flaxseed. Just one ounce, a small handful, each day is plenty.
• Blueberries and grapes get their deep colours from anthocyanins, powerful antioxidants shown to improve learning and recall in studies at the University of Cincinnati.
• Sweet potatoes are the dietary staple of Okinawans, the longest-lived people on Earth who are also known for maintaining mental clarity into old age. Sweet potatoes are extremely rich in betacarotene, a powerful antioxidant. Other bright orange vegetables such as carrots and butternut squash also contain high levels of beta carotene.
• Green leafy vegetables provide iron in a form that is more absorbable when the body needs more and less absorbable when you already have plenty, protecting you from iron overload which can harm the brain. They are also loaded with folate, an important brain-protecting B vitamin.
• Beans, lentils and chickpeas have vitamin B6 and folate, as well as protein and calcium, with no saturated fat or trans fat.
• Vitamin B12 is essential for healthy nerves and brain cells. While many people have trouble absorbing vitamin B12 from foods, B12 in supplements is highly absorbable. Together, folate, vitamin B6, and vitamin B12 eliminate homocysteine, which can build up in the blood and damage the brain.
Q: B12 in foods: could you please advise about foods that are rich in vitamin B12, rather than taking a supplement?
Dr Barnard: Vitamin B12 is the one vitamin for which the best sources are supplements, not foods. The US Government has long recommended that all persons over age 50 take a B12 supplement, and that is good advice for everyone.
Vitamin B12 is not produced by animals or plants, it is made by bacteria. So, historically, the traces of bacteria in the soil, on plants, on our fingers, or in our mouths would have provided traces of B12 – at least that is what some scientists believe.
The bacteria in a cow's gut will produce B12 (just as the bacteria in the human gut do), and traces of B12 will end up in meat. However, it is bound to protein, and many people have trouble absorbing it. This is true for older people, as I mentioned, and also for people who have trouble producing stomach acid, who are on antacids or acid-blocking medications, who take metformin for diabetes, or who have Crohn's disease, among other conditions.
Homocysteine: a natural enemy
Homocysteine is an amino acid in the human body which needs to be eliminated and excreted efficiently. To neutralise it, the body needs B vitamins, especially vitamin B6 and B12.
If homocysteine isn't neutralised and excreted, it can cause cellular damage, especially to veins and arteries, and potential blood clots.
This can lead to heart disease, stroke and damage to the brain. High levels of homocysteine is the most accurate predictor of your potential risk of developing heart disease or a stroke.
A blood test requested by your GP can measure your homocysteine levels. I had mine done in St. Vincent's. The blood has to be kept chilled as it goes to the lab for this test, hence doing it at the hospital.
If your homocysteine levels are considered high, B vitamin rich foods will help to manage it. Your doctor can refer you to a dietician if necessary.
Get Your Heart Pumping – A 40-minute brisk walk three times per week brings oxygen to your brain and has been shown in University of Illinois studies to reverse brain shrinkage and improve memory.
Mental Exercises – Brain stimulation – from books, newspapers or online brain-training exercises – measurably strengthens the brain.
Sleep – Sleep is essential for preserving memories. The first half of the night is important for slow wave sleep, when your brain integrates facts and words learned during the day.
The second half of the night emphasises REM sleep, when emotions and physical skills are integrated.
Bar one or two quite specific instructions, this is good general dietary and lifestyle advice.
Source: Neal Barnard, MD, is one of America's most well-respected nutrition authorities. He is an Adjunct Associate Professor of Medicine at the George Washington University School of Medicine and Health Sciences, Board-Certified by the American Board of Psychiatry and Neurology, and President of the Physicians Committee for Responsible Medicine in Washington, DC.
His new work aims to put the findings of research to work to prevent risks to brain health. He is the author of 15 books and host of three PBS television specials.
- Recipes taken from Delish and Relish Cookbooks by Rozanne Stevens. For cookbooks and healthy cookery courses, log on to www.rozannestevens.com
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