“Alzheimer’s is mainly a question of lifestyle habits”

And yet what is the likelihood of suffering from this disease, which is by far the most common type of dementia? It’s time to talk to Professor Konrad Beyreuther, a renowned researcher in the field of Alzheimer’s who spoke at the “3rd International Symposium Healthy Ageing” – organized by the Leibniz Research Alliance (LRA) Healthy Ageing and the Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP).

We are getting older and older. Only a few years ago, researchers argued that aging alone leads to a dramatic increase in the number of Alzheimer patients. And yet the opposite appears to be the case. How come?

Konrad Beyreuther: It is indeed the case that Western industrialized countries are experiencing a 25 percent drop in the number of new cases in the post-war generation compared to previous generations. There are two reasons for this.
To begin with, we have undergone a cognitive revolution. Dementia involves the loss of acquired knowledge – and nowadays, people simply possess much more knowledge. As such, they have far more nerve cell contacts and a well
connected brain is in a much better position to compensate for nerve cell loss. So people are much less likely to succumb to “Mr Alzheimer’s”. Secondly, we have experienced a cardiovascular revolution. Thanks to medical advancements, we are now able to treat heart attacks quickly, remove clots and calcareous particles via catheters, and even replace heart valves using a minimally invasive procedure. The heart is a very important organ for the functioning of the brain. We are able to run for two hours without needing to eat – but the brain only has enough sugar for us to think for five minutes. So the heart has to keep on pumping sugar to the nerve cells.
Incidentally, we are not seeing a similar decline in developing countries that experience food deficits, and where primary education is not compulsory. Poverty is the biggest risk factor for dementia. Unfortunately, this is usually forgotten.

Above all, people whose parents succumbed to Alzheimer’s worry that the same fate awaits them. Do they have anything to worry about?

No. Alzheimer’s is not a hereditary disease. We know that only 0.1 percent of people with a particular gene mutation will be unable to avoid the disease. And then there are 30 genes that play a role in seven percent of cases. We know that the gene for the cholesterol transport protein ApoE e4 is mutated in 50 percent of Alzheimer’s patients, which why they have too much cholesterol in the blood. If cholesterol levels can be reduced, preventing strokes and heart attacks, the risk associated with ApoE e4 disappears! Which leaves us with just 3.9 percent. In other words: In 96.1 percent of people, the risk of getting Alzheimer’s disease is dependent on lifestyle habits, and can be prevented. Which is really good news.

What are the main risk factors for Alzheimer’s disease?

We know of eight: diabetes is one of them, obesity, an unhealthy diet, hypertension (high blood pressure and high cholesterol) and smoking. Also depression, which means fewer synapses! So we really need to treat depression. Synapses are also destroyed under stress. (Positive stress, on the other hand, reduces the risk.) Lack of exercise and – a newly discovered risk factor – hearing loss. Insufficient new information reaches the brain of those with bad hearing. But hearing aids can compensate for this. Incidentally, age itself is not a risk factor! Of course Alzheimer’s occurs more frequently in old age. But this is because Alzheimer’s sets in unnoticed at a very early age: between the age of 20 and 40 in people with hereditary risk factors (such as ApoE e4), or otherwise over the age of 40.

What can we do to minimize our risk of developing Alzheimer’s?

Do lots of exercise combined with mental activity (count backwards), reduce obesity, and follow a balanced diet. And get sufficient sleep, seven hours minimum! It is particularly important to have a deep sleep. This is when we assess and process everything we have learnt and experienced over the day, which is then transformed into synapses. It is also when metabolic products are washed out of the brain. Via aquaporins, fine “water channels” in the cell membranes of the
blood vessels of the brain.
It is also good to stimulate autophagy – i.e. boost the organism by intermittent fasting, which leads to the degradation and exploitation of cellular components that are no longer used. It is advisable to eat little once a week or at least to leave a period of twelve hours between the last and the first meal of the day.

What do you understand by a balanced diet?

Not too much of one thing, and variation. Sufficient protein (one gram per kilogram of body weight); but carbohydrates and fats are also important. Why protein? Those who move build up their muscles, which happen to consist mainly of
protein. If you eat too little protein, the body will take it from elsewhere, killing functioning cells to obtain protein. Which is not a good thing. Eating muesli with fresh fruit, for example, is a perfect start to the day. Lots of vegetables – for fiber, we don’t eat enough vegetables! Fish and, for those who tolerate it, meat (but in moderation), soy, pulses, and low-fat cheese. But it is up to you. After all, I believe that enjoyment and quality of life are essential to successful aging. But make sure you can fasten your belt in the same hole, is what I always say. With the exception of Christmas, Easter and vacations, of course ;-).

You also advise people to consciously build up a “cognitive reserve.” How does that work?

This can be summed up in four words: Learning. Running. Loving. Laughing. Games such as chess, backgammon and concentration – I play concentration myself, and I am getting better and better at it! Lots of reading. Ball games such as soccer, tennis, badminton and golf are good because you need coordination and forethought for those.
And dancing in particular, i.e. the ideal thing is to listen to music and transform it into coordinated movement! Intensive social contacts are also extremely important. Making plans, consciously perceiving your environment. Leading an active life in all respects – that’s the best way to train your memory.

What if I think I’m already slightly “muddled”? Can these factors still help?

Definitely. This is the finding of FINGER, a Finnish prevention study involving people with first signs of cognitive impairment. They first had to lower their blood pressure, lose weight and change their diet; they were then asked to exercise for 30 minutes a day, play computer games twice a week, meet up as a group, and maintain social contacts. Follow-up observations revealed that those who took part in the program slipped into dementia seven years later that the control subjects.

What is your forecast for future generations?

I think that our great-grandchildren will no longer come across Alzheimer’s as a disease. Changes in the brain will still occur – but they will no longer be able to become manifest as dementia during their lifetime. Why is this the case? The IT age means that people will have an even higher cognitive reserve than is currently the case. And they will exercise more because they know how important the heart is for the brain. But there will still be a few people who slip into the disease through no fault of their own, following a stroke or a heart attack. So we need medication for them. But with 20,000 people currently researching Alzheimer’s, I am confident that there will soon be a breakthrough.

You say that Alzheimer’s is a result of thinking and memory formation. Does that mean, conversely, that those unable to think will not become demented?

That’s right. Animals do not get Alzheimer’s. It has not yet been investigated whether parrots get dementia. In dogs and horses, we find the typical protein deposits in the blood vessels, but not in the brain. Alzheimer’s is a human disease. But, as I said: Thinking also protects you from the disease!

Catarina Pietschmann
Translation: Teresa Gehrs