thinking, remembering and reasoning-is fast becoming a major threat to human
health. In the UK alone, around 700,000 people are currently living with
dementia, and this figure is expected to double in 30 years' time.
Although many people assume that a loss of mental agility is an inevitable
part of ageing, recently, a number of factors have been identified that may
slow or even prevent the development of dementia. Here are some simple steps
you can take to help keep your mind sharp for years to come.
- Exercise. In an international review of the literature up to
December 2005, Dutch scientists from the Lifestyle and Health Research Group
in Utrecht concluded that aerobic exercise is good for the brain and the
body. Eight studies, involving 670 adults aged 55 and over, found that
aerobic activities such as running and cycling significantly increased
cardiorespiratory fitness, an improvement that coincided with better mental
function. Compared with non-exercisers and those who followed a yoga- or
strength-based programme, aerobic exercisers had improved motor function,
cognitive processing speed, memory, and auditory and visual attention
(Cochrane Database Syst Rev, 2008; 3: CD005381).
These findings support earlier results suggesting that people who regularly
engage in physical activity-even just walking-have substantially lower risks
of dementia and cognitive decline (BMJ, 2004; 329: 761; Arch Neurol, 2001;
- Keep your mind active, too. Mental stimulation can help to ward off
dementia. The ongoing Einstein Aging Study, started in 1980 in the US, has
found that elderly people with hobbies such as reading, or playing board
games or musical instruments, were sig-nificantly less likely to have
Alzheimer's or other types of dementia (N Engl J Med, 2003; 348: 2508-16).
Higher levels of education and lifelong learning also appear to have
protective effects on the brain (Neurology, 1994; 44: 2073-80; West Indian
Med J, 2002; 51: 143-7).
- Minimize exposure to heavy metals. Alumin-ium, mercury and other
heavy metals have been implicated in dementia (see WDDTY vol 18 no 2), so
avoiding these as much as possible may be beneficial. Removing dental
amalgam fillings (see The WDDTY Dental Handbook for how to have this done
safely), installing a good-quality water filter, and being careful about
which household and personal-care products you use should help to reduce
your toxic-metal exposure.
Also, consider including foods and supplements such as
Chlorella, coriander and selenium into your diet as they have natural
chelating (binding) properties. (For more information on other natural ways
to rid the body of heavy metals, see WDDTY vol 19 no 2).
- Avoid toxic pesticides. Occupa-tional studies show that those who
are regularly exposed to pesticides have a greater likelihood of develop-ing
Alzheimer's (Occup Environ Med, 2007; 64: 723-32). Using natural, non-toxic
alternatives whenever possible (see WDDTY vol 19 no 2) can contribute to
- Maintain a healthy heart. Heart-related health factors appear to
predispose people to dementia. In
a 40-year study, raised cholesterol levels in midlife (240
mg/dL or higher)-even levels considered to be only borderline high (200-239
mg/dL)-dramatically increased the risk of Alzheimer's and vascular dementia
later in life (Dement Geriatr Cogn Disord, 2009; 28: 75-80). Other research
has linked dementia with high blood pressure, obesity and insulin resistance
(Expert Rev Neurother, 2009; 9: 617-30). In particular, those in their 40s
who carry a lot of weight around their middle have a threefold higher risk
of developing dementia in their senior years (Neurology, 2008; 71: 1057-64).
These studies suggest that controlling your weight, blood pressure, blood
sugar and choles-terol can help to prevent the onset of dementia later on.
- Eat the right fats. People who consume large amounts of saturated
(animal) fats have an increased risk of cognitive decline. High intakes of
monounsaturated and polyunsat-urated (particularly omega-3) fats, on the
other hand, lead to a clear reduction of risk (Ageing Res Rev, 2009 Jul 28;
Epub ahead of print). Monounsaturated fats come from foods such as olive
oil, nuts and avocados, while polyunsat-urated fats are found in safflower
oil and seafood. In fact, just eating fish or some other type of seafood at
least once a week can reduce the risk of dementia by around 30 per cent
(BMJ, 2002; 325: 932-3). However, as many types of fish contain mercury,
limit your consumption of high-risk fish (such as shark, swordfish and tuna)
and choose smaller, less polluted types of fish and seafood [such as
anchovies, pilchards, prawns, sardines, salmon (Alaskan wild/ canned
pink/sockeye), cod and catfish].
- Increase antioxidants. Dietary antioxidants, especially vitamins C
and E, appear to lower dementia risk. Of more than 5000 adults aged 55 and
over, those who consumed lots of foods containing vitamins C and E had a
lower risk of Alzheimer's. Smokers benefited in particular,
with a risk reduction of about 40 per cent (JAMA, 2002; 287: 3223-9).
Getting enough selenium may also be important. Among more than 2000 rural
Chinese aged 65 and older, those who had the lowest lifelong selenium levels
scored the worst in cognitive tests (Am J Epidemiol, 2007; 165: 955-65).
- Supplement with other nutrients. Other nutrients can also help to
stave off cognitive decline. In elderly people with mild cognitive
impair-ment, supplementing with acetyl-l-carnitine (an amino acid) at doses
of 1500 mg/day led to significant improvement in mental
function, especially memory (Clin Ter, 1990; 132: 479-510). Supplementing
with folic acid, and vitamins B6 and B12, may also be beneficial for those
who are deficient in these nutrients (J Nutr Health Aging, 2008; 12:
- Consider herbs. Those that appear to be neuroprotective include:
v Ginkgo biloba. Although recent evidence suggests
that 120 mg of Ginkgo twice daily in people aged 75 years and over did not
reduce the incidence of dementia (JAMA, 2008; 300: 2253-62), previous
studies, including a review of the literature, have shown that the herb can
improve mental function in those with mild-to-moderate cognitive impairment
(Curr Med Res Opin, 1991; 12: 350-5; Public Health Nutr, 2000; 3: 495-9).
v Curcumin. Recent evidence-albeit in animals and so
may not apply to humans-suggests that curcumin, the main compound in the
spice turmeric, may help to prevent or even reverse cognitive decline. Rats
with experimental dementia (induced by a brain-damaging chemical) showed
improved cognitive performance after just three weeks of curcumin
supplementation in comparison to rats given a placebo and which showed no
such improvement (Eur Neuro-psychopharmacol, 2009; 19: 636-47).
v Bacopa monniera. This tradi-tional Ayurvedic herb
(also known as 'water hyssop') appears to enhance several aspects of mental
function and learning capacity. In a double-blind, placebo-controlled trial,
healthy volunteers taking 300 mg/day of B. monniera extract showed
significant improvements in their learning rates and memory compared with
those taking a placebo. Maximum effects were seen after 12 weeks
(Psychopharma-cology [Berl], 2001; 156: 481-4).
- Drink red wine. A moderate consumption of red wine is asso-ciated
with a lower incidence of Alzheimer's disease and other forms of dementia.
Findings in animals (which may not apply to humans) suggest that the
polyphenol resveratrol might be responsible for the apparent neuroprotective
effects of red wine (BMC Neurosci, 2008; 9 Suppl 2: S6).
- Keep socially connected. Having a social-support system appears to
play an important role in main-taining a healthy mind. Indeed, the evidence
apparently suggests that those who have the least social interactions also
have the highest incidence of dementia (Lancet, 2000; 355: 1315-9).
Types of dementia
- Alzheimer's disease, the most common type of dementia, is when
clumps of protein called 'amyloid plaques' and bundles of fibers
('neurofibrillary tangles') develop in brain tissue and disrupt the normal
workings of the brain.
- Vascular dementia, the second most common type, is when interruption
of the brain's blood supply, usually due to 'mini-strokes', causes
- Dementia with Lewy bodies is where abnormal clumps of proteins known
as 'Lewy bodies' develop in the nerve cells of the brain stem and cortex.
- Frontotemporal dementia, an unusual form of dementia, is when the
frontal and temporal lobes of the brain shrink. Unlike other types of
dementia, this form usually develops in people aged under 65.
Drugs linked to dementia
Several prescription drugs have been associated with memory loss, confusion
and other symptoms of dementia, including:
v statins (Pharmacotherapy, 2003; 23: 871-80)
v benzodiazepine tranquillizers (Vertex, 2001; 12: 272-5)
v antidepressants (Ann Clin Psychiatry, 2004; 16: 15-25)
v steroids (Drugs Aging, 1993; 3: 349-57)
v beta-blockers (Drugs Aging, 1999; 15: 15-28)
v anticholinergics (Arch Gerontol Geriatr, 2007; 44 Suppl 1:
v opioids (Drugs Aging, 1993; 3: 349-57)
v non-steroidal anti-inflammatory drugs (NSAIDs) (Drugs Aging,
1999; 15: 15-28).
Vol 20 07 October 2009