Alzheimer's - the answers lie in diet and lifestyle

Image: Lightspring /
Image: Lightspring /
Alzheimer's disease is on the rise. Some 44 million people worldwide are estimated to have the disease today, at a cost of over $600 billion. By 2050 the number is expected to treble. But could diet and lifestyle changes reduce its incidence?
The overwhelming priority should therefore be to prevent people from getting Alzheimer's and other dementias in the first place.

The UK Government has announced an increase in funding for dementia research - from the 2015 target of £66 million, to £132m in 2025. Health Secretary Jeremy Hunt has also promised to provide £500m in additional support for carers.

"This mustn't be about paying lip service to dementia", he said. "It must be about actually changing things - and the biggest thing we can do is make sure we have a proper diagnosis to people."

Diagnosing Alzheimers and other dementias is indeed important. But far more important is to save people from getting it in the first place. And this focus is lacking from current expenditures - even though it is amply documented that many diet and lifestyle factors can significantly reduce the incidence of Alzheimer's.

These changes also yield other highly worthwhile benefits - happier lives, more friends, greater fitness, and improved cardiovascular health.

As it happens I wrote an article on this very topic for The Ecologist in October 2007 (reproduced below). I had hoped that its publication might help to swing the focus of research away from expensive proprietary pharmaceuticals, and towards the kind of preventative measures that people can adopt in their own lives. As it turns out, my hopes were in vain.

But the facts remain. And so does the terrible truth that Alzheimer's disease appears to be an irreversible condition. Once acquired, it is possible to slow down its progress. But it is impossible to turn the disease back, or reverse the damage it inflicts on the brain.

Reducing Alzheimer's incidence

Since 2007 the incidence of the disease (then 700,000 in the UK), and its treatment cost (then £17 billion), have only increased. It is high time for governments - in the UK and other countries - to recognise that the answer to Alzheimers is to stop people getting it in the first place, and that this is where resources should be focussed

This means investing in healthy diets, regulating health-impairing trans fats, rebuilding the social infrastructure of day centres for elderly people, training care workers in keeping ageing minds active and involved, creating opportunities for the elderly to exercise and keep fit.

It will all cost money - but nothing like so much as inaction. And as children and other relatives of Alzheimer's victims know all too well, the cost of the disease is far more than a merely economic one.



Alzheimer's - the case for prevention

Alzheimer's and other dementias are dreadful diseases. They are also expensive. Just how expensive was revealed by the Alzheimer's Society in its Dementia UK report in February 2007.

The overwhelming priority should therefore be to prevent people from getting Alzheimer's and other dementias in the first place.

The cost to the UK is £17 billion a year, or around £25,000 a year for each of the 700,000 sufferers of late-onset dementia. The number of sufferers is projected to rise: to 940,110 by 2021, and to 1,735,087 by 2051.

In response to the looming crisis, the Society makes seven sound recommendations. But something essential is missing: prevention. There are many cost-effective, scientifically robust steps that could dramatically reduce the incidence of dementia and enable elderly people to retain their cognitive faculties, especially in the areas of diet, nutrition and lifestyle.

Applied systematically, these measures have the potential to transform the entire Alzheimer's risk landscape.

Brain-healthy oils

The brain is a fatty organ, and works best when fed the right kinds of oil and fat. It responds especially badly to the industrial trans fats found principally in hydrogenated oil. A 2003 study in the Archives of Neurology, which surveyed 815 people over 65, found that the 20% with the highest trans fat consumption were four times more likely to develop Alzheimer's than the 20% with the lowest trans fat consumption.

The same study found that the 20% with the lowest consumption of polyunsaturated vegetable oils were five times likelier to develop Alzheimer's than the 20% with the highest consumption.

Combine these effects, and someone eating a diet high in trans fat and low in polyunsaturated fat is nine times more susceptible to Alzheimer's than someone eating a low trans fat, high polyunsaturated fat diet.

A 1999 study in the journal Neurology is one of many to show the benefit of mono-unsaturated oil, especially the oleic acid in olive oil. It suggests that, as people age, their brain chemistry may need more monounsaturated fat to prevent degeneration:

"High MUFA [monounsaturated fatty acid] intake per se could suggest preservation of cognitive functions in healthy elderly people. This effect could be related to the role of fatty acids in maintaining the structural integrity of neuronal membranes."

Omega-3 oils, especially the long-chain EPA and DHA essential fatty acids, are a prerequisite of a healthy brain function and have successfully treated depression, attention deficit hyperactivity disorder (ADHD) and other mental conditions. Evidence published in the Journal of Neuroscience in 2005 shows that these oils reduce build-up of the amyloid plaque linked with Alzheimer's in mice, and may also help humans.

This supposition was supported in an October 2006 study in the Archives of Neurology. The one-year study of 204 Alzheimer's sufferers showed that the decline of very early-stage patients was significantly slowed by taking Omega-3 supplements.

"It seems that not only is DHA an important structural component of brain cells but DHA and its metabolites seem to exert a preventive effect against development of brain cell death", commented the authors.

"These positive findings now indicate that early treatment with Omega 3 can help to reduce memory decline in patients experiencing the early symptoms of Alzheimer's."

Vitamins to the rescue

The risk of dementia is strongly correlated with higher levels of homocysteine - a rogue amino acid associated with low levels of folic acid and vitamin B12 - as noted in the American Journal of Clinical Nutrition, February 2007. Treatment with B12 is protective: "Higher plasma vitamin B12 may reduce the risk of homocysteine- associated dementia or CIND (cognitive impairment without dementia)."

Vitamin D also protects against dementia, as shown in a 2006 study of 80 participants, half with mild Alzheimer's and half without. It concluded: "Vitamin D deficiency was associated with low mood and with impairment on two of four measures of cognitive performance."

Protection is also conferred by the polyphenol antioxidants in fruit and vegetables, as shown in a 2006 paper in the American Journal of Medicine, based on a study of 1,836 Japanese Americans. Those who drank juice at least thrice weekly were a quarter as likely to contract Alzheimer's as those who drank juice less than once a week:

"Fruit and vegetable juices may play an important role in delaying the onset of Alzheimer's disease, particularly among those who are at high risk of the disease."

Turmeric, the base spice of every curry, is strongly protective. It is rich in the oily chemical curcumin, which triggers our defence mechanisms against free radicals, a cause of cellular damage and a keypart of the ageing process. There's a host of evidence for curcumin's benefits, not just in Alzheimer's but in a broad range of pathologies from Crohn's disease to psoriasis.

This is supported by the low incidence of Alzheimer's in India. One 2001 study in Neurology of a rural population at Ballabgarh, India, found a 0.3 % incidence, "among the lowest ever reported" -and roughly a quarter of that of a reference US population.

Brain health = cardiovascular health

The same dietary changes that reduce the risk of Alzheimer's would also strongly benefit cardiovascular health, reducing heart disease and stroke. Mental and cardiovascular health are strongly correlated, as shown by a 21-year study of 1,500 Finns by Miia Kivipelto of the Karolinska Institute, Stockholm.

"Midlife obesity, high total cholesterol level, and high systolic blood pressure were all significant risk factors for dementia", each doubling the risk, "and they increased the risk additively", so that people with all three risk factors were 6.2 times more likely to succumb to dementia.

Friends, family and mental exercise

Another vital dementia-prevention strategy is to stay lively and mentally active. In June 2003 the New England Journal of Medicine published a study of 269 healthy adults between 75 and 85 over a 21-year period, which found that "reading, playing board games, playing musical instruments, and dancing were associated with a reduced risk of dementia" - a 75% reduced risk, for those who were most mentally active.

"It seems that remaining mentally agile makes the brain more healthy and more likely to resist illness, just as physical exercise can protect the body from disease", said lead author Dr Joe Verghese. Numerous other studies have confirmed these findings.

Loneliness is another important factor, as a study by Professor Robert Wilson, professor of neuropsychology at Rush University Medical Centre, revealed in February 2007.

His study of 823 older people in the Chicago area found that the risk of Alzheimer's "was more than doubled in lonely persons" compared with those who were not lonely. "Loneliness was associated with lower level of cognition at baseline and with more rapid cognitive decline during follow-up", his team also found.

In recent months the Alzheimer's Society has accepted the need to assess the potential benefits of low-cost preventative measures. But the vast majority of its efforts are still aimed at securing drug therapies (many of dubious efficacy and with undesirable side effects) and adequate care for sufferers.

Disproportionate medical research funding is also applied to patentable genetic technologies such as the role of inherited genetic predispositions, and the use of genetically modified cell transplants to produce Nerve Growth Factor.

The Government's response? There isn't one

But the greatest disgrace is that the growing compendium of medical knowledge about diet, nutrition, lifestyle and dementia has produced no policy response from the Government.

It is hard not to question whether it suits the Government to have the elderly population die relatively young. All the measures that would slow or prevent the onset of dementias would also extend life, especially through improved cardiovascular health, and thus increase pension, benefit, housing and other health costs.

But with the cost of Alzheimer's and other dementias projected to rise to alarming levels in the absence of preventative action, a rethink should (sooner or later) be on the way. Meanwhile, all of us can try, in our own lifestyles, to stay out of the dementia danger zone.



Oliver Tickell edits The Ecologist website.

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