03 Dec 2013
PROFESSOR HENRY BRODATY, MD, PhD
Prevention
We all become slower and more forgetful as we age, some of us more than others. When this change is accelerated and interferes with a variety of thinking or cognitive abilities and interferes with our day to day functioning, this is diagnosed as dementia, of which the most common type is Alzheimer’s disease.
Surveys of the population indicate that dementia in general and Alzheimer’s in particular, along with cancer, are the health problems that we generally fear most. Rightly so! As we are living longer the chances of developing a dementia increase dramatically – at least affecting 5% (or some estimates 8%) of people over 65 years of age, rising to 30% of people aged over 90 and 50% of those reaching 100. Glass half empty people will be despondent about these figures. Glass half-full people will say, what can I do to be like the 50% of mentally sharp centenarians?
I will focus now on the question of whether we can prevent Alzheimer’s disease. The short answer is “No”. But we can delay its onset. In general, what is good for our heart is good for our brain. Here are some key lifestyle changes we can adopt. The good news is that it is never too early and never too late to consider embracing these recommendations, based on Alzheimer’s Australia's prevention program (these steps have been recently been superceded by the 5 Simple Steps to Maximise Your Brain Health (PDF) message).1,2
- Mind your body
- Mind your mind
- Mind your diet
- Mind your habits
- Mind your health checks
- Mind your social life
- Mind your head2
1. Mind your body
Exercise is good for your heart, bones, muscles, mood and brain. It does not need to be much, a brisk walk 30 minutes a day for five days per week. More is better. Getting puffed and sweaty may be better still. There is some evidence that resistance training (e.g. weights) in addition to aerobic exercise (e.g. aquarobics, fast walking, swimming) might be even better. You should check with your doctor about precautions if you have a heart, joint or bone condition that may limit your capacity to exercise. If 30 minutes is too much, try 10 minutes and slowly build up or split the 30 minutes in 2-3 sessions during the day.
Starting is a lot easier than maintaining an exercise routine. Try to make it fun – do it with a friend, do what you enjoy (e.g. ballroom dancing is popular), make it a priority in your daily schedule.
2. Mind your mind
Keep mentally agile. Stretch your brain. Learning something new or new skills. Crosswords and Sudoku are popular and may be helpful but if you have been doing these for years the benefit is less. Commercial computer cognitive training programs such as Lumosity and Posit Science have research support and are increasingly popular. These programs require you to spend an hour a day, at least 3 days per week for at least 8 weeks to reap cognitive rewards. They are structured to improve your verbal and visual memory and speed of information processing. The programs progress you one level at a time, once you achieve a minimum of proficiency, say 85% correct. The benefits tend to wane unless you do booster sessions after the course is completed.
3. Mind your diet
There is evidence that diets that are low in saturated fats and high antioxidants may be beneficial for our brains. Several studies, but not all, have shown that the Mediterranean diet offers some protection against Alzheimer’s disease. Fish has also been reported to be beneficial. The Mayo Clinic states that the Mediterranean diet emphasises3:
- Eating primarily plant-based foods, such as fruits and vegetables, whole grains, legumes and nuts
- Replacing butter with healthy fats, such as olive oil
- Using herbs and spices instead of salt to flavour foods
- Limiting red meat to no more than a few times a month
- Eating fish and poultry at least twice a week
- Drinking red wine in moderation (optional)
The diet also recognizes the importance of being physically active, and enjoying meals with family and friends. The Mediterranean diet traditionally includes fruits, vegetables and grains. For example, residents of Greece average six or more servings a day of antioxidant-rich fruits and vegetables.
Grains in the Mediterranean region are typically whole grain and usually contain very few unhealthy trans fats, and bread is an important part of the diet. However, throughout the Mediterranean region, bread is eaten plain or dipped in olive oil — not eaten with butter or margarine, which contains saturated or trans fats. Nuts are another part of a healthy Mediterranean diet. Nuts are high in fat, but most of the fat is healthy. Because nuts are high in calories, they should not be eaten in large amounts — generally no more than a handful a day. For the best nutrition, avoid candied or honey-roasted and heavily salted nuts.
The evidence of alcohol is less clear. Some studies show that people who have low to moderate alcohol intake have a lower rate of Alzheimer’s than those who are teetotal. Others refute this. What all agree on is that heavy alcohol use is bad for your brain. Recommendations are to limit intake to 2 standard drinks per day, and even less for women. Wine, especially red wine which contains polyphenols, may offer most protection, but more is not better.
Vitamins and dietary supplements
It seems that food sources of vitamins are better than taking supplements. For example people who eat fish more than once per week have been reported to be less likely to develop Alzheimer’s disease; the evidence for taking omega 3 supplements (especially found in oily fish such as salmon) is less convincing.
An exception may be taking high doses of vitamin B12, B6 and B9 (folic acid). A group form Oxford have shown this combination in older people complaining about their memory was associated with less shrinkage of their brains on MRI scans over two years and better cognitive function.
Obesity and type 2 Diabetes
Mid-life obesity and type 2 diabetes are independent risk factors for heart disease. They are also independent risk factors for Alzheimer’s disease. We can do something to avoid both – see diet and exercise.
4. Mind your habits
No smoking! We all know smoking is bad for your heart and is a risk factor for cancer and for stroke. We now know that smoking is also a risk factor for Alzheimer’s disease. The good news for smokers, is that a study found this risk only held for current smokers. In other words, give up now.
5. Mind your health checks
High blood pressure in mid-life increases the risk for heart disease, stroke and Alzheimer’s disease. A large French study found that treating hypertension reduced the risk for all causes of dementia and Alzheimer’s disease. Ask your GP to check your blood pressure at least annually and treat if it is high. This may not require pills; diet and exercise can reduce high blood pressure. After about age 75, too vigorous treatment of blood pressure can be deleterious.
Many clinicians recommend checking your fasting blood sugar, lipids (cholesterol) and homocysteine as well as your thyroid, Vitamin D, blood count and iron levels; discuss with your doctor if these are indicated.
6. Mind your social life
People who are more socially engaged have less Alzheimer’s disease when followed up several years later. It may be that the social engagement is associated with less depression, better cognitive abilities and being more active in general. An alternative explanation is that the build-up of Alzheimer’s disease pathology over 20-30 years before symptoms become apparent may lead to decreased confidence and socialisation.
7. Mind your head
Alzheimer’s has been controversially linked to head injuries. In any case it makes sense to wear a helmet if engaging in an activity with risk of head injury such as riding a bicycle.
8. And there’s more …
People who have had depression have higher risk of Alzheimer’s. This association is not strong and it is unclear whether treatment for depression reverses this risk. Some researchers have even postulated that it is the treatment that is the risk factor but this has not been proven.
9. A word of caution
Remember, just because there is an association between a risk factor and a disease, it does not mean that everyone one who has been depressed, had a head injury or has type 2 diabetes will develop the condition. It just means there is a statistically higher risk than the rest of the population. So follow the prescription above, live healthy and don’t worry or stress.
Check our website for latest on healthy brain ageing research: www.cheba.unsw.edu.au This article was published in the Montefiore November 2013 Chanukah LIFE magazine.
Professor Henry Brodaty is Co-Director of the Centre for Healthy Brain Ageing, Director of the Dementia Collaborative Research Centre - Assessment and Better Care, Senior Psychogeriatrician, Aged Care Psychiatry, Prince of Wales Hospital. He is the Medical Advisor to Alzheimer's Australia, the Montefiore Chair of Healthy Brain Ageing and was recently appointed the President of the International Psychogeriatric Association.
