Dementia: a background
Some memory problems associated with ageing are more serious than others. People with substantial changes in their memory, personality, and behaviour may suffer from a form of brain disease called dementia. Alzheimer’s disease is one of many types of dementia.  Globally it is one of the most disabling and burdensome health conditions because it seriously affects a person’s ability to carry out daily activities.  In recent years, scientific studies have shown that omega-3 fatty acids from fish may be of benefit.

The Efamol Scientists
Nearly twenty years ago, scientists at the Efamol Research Institute first discovered that people with Alzheimer’s disease have lower than normal blood levels of the omega-3 fatty acid, docosahexaenoic acid (DHA)1.

Over the next two decades, these results were confirmed by other research groups2 including one that found the disease became worse as blood DHA levels progressively dropped3. Others reported low brain DHA levels in patients with Alzheimer’s disease compared to healthy people4,5.

Research that matters
Nowadays, we know that people with low DHA status are more likely to develop Alzheimer’s disease. One of the first studies to report this involved 1188 volunteers who were followed for 10 years to assess development of Alzheimer’s disease6.

Those with low DHA levels at the start of the study had a 67 percent greater risk of developing Alzheimer’s disease later on. However, blood levels of another omega-3 fatty acid called eicospaentaenoic acid (EPA) which is also found in fish, were not related to disease development indicating that DHA status was most important.

Another study showed that people with high blood DHA levels are half as likely to develop dementia. It included 899 initially healthy volunteers of about 76 years of age7and showed that people with the highest blood DHA levels had a 47 percent lower risk of developing dementia, even when taking into consideration their body mass index, diabetes, high blood pressure, smoking and other known promoting factors. 

This study also showed that eating more fish, and specifically eating more DHA, can reduce the risk of developing Alzheimer’s disease. Those who ate two or more servings of fish per week were 39 percent less likely to develop dementia, but those who ate less than that did not derive any benefit. Although oily fish contains both DHA and EPA, it was only the DHA that was responsible for preventing Alzheimer’s disease. At least eight additional studies have linked high fish and/or DHA intake to a lower incidence of dementia including Alzheimer’s disease8-16.

Studies in support of supplements
The first double-blind, placebo controlled trial to measure the effects of omega-3 supplementation included 204 patients with mild to moderate Alzheimer’s disease17. 

Patients were treated with either 1.7 g of DHA and 0.6 g of EPA or a placebo for 6 months, after which all received the fish oil treatment for another 6 months.

Brain function was measured using a variety of standardized tests and blood levels of EPA and DHA were measured before and after treatment. At six months, in a subgroup of 32 mildly effected patients treated with omega-3 fatty acids, there was a significant reduction in mental decline rate compared with the placebo group.  A similar arrest in decline rate was observed between six and twelve months in the placebo subgroup when receiving the active treatment.  Blood fatty acid levels of DHA and EPA were significantly below normal at the start of the study, but after six months of omega-3 treatment there was a 2.4 and 3.6 fold increase in DHA and EPA respectively.  After twelve months supplementation, both groups had similar blood levels of these two fatty acids.

This study showed that omega-3 supplementation delays the rate of mental decline in patients with very mild Alzheimer’s disease and stresses the importance of early supplementation as it could halt progression of the disease.

Last year, a randomized, double-blind, placebo-controlled clinical study18 included 23 patients with mild or moderate Alzheimer’s disease and 23 with age related cognitive decline (a less severe form of mental deterioration that often eventually leads to Alzheimer’s disease).  They took either 1.8 g/day of Omega-3 (1080 mg EPA + 720 mg DHA) or a placebo for 24 weeks. 

Memory and brain performance tests including those measuring disease severity and progression of illness completed at the start of the study and at weeks 6, 12, 18 and 24 showed that improvements were more apparent in people with age related cognitive decline than in those with Alzheimer’s disease.

Those results tell us that supplementation needs to be started early in life to prevent development of more severe forms of memory decline which respond less favorably.

To conclude
Currently, 24 million people worldwide have dementia and 80% of those with age related cognitive decline are diagnosed with Alzheimer’s disease within 6 years19.  Omega-3 supplementation may be a cheap and simple way of reducing the likelihood and severity of this cruel and debilitation condition.

Efalex Active 50+, the first fish oil supplement specifically designed for the over 50s, contains a unique combination of ingredients known for their beneficial role in maintaining healthy brain function and performance, including Fish oils, Phosphatidylserine (PS), Ginkgo biloba, Vitamin B12 and folic acid. Available from Boots, Holland & Barrett, independent pharmacies and health food stores and online from www.efamol.com, Efalex Active 50+ is priced from £9.49 for 30 capsules. 

 

References:
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3. Tully AM, Roche HM, Doyle R, Fallon C, Bruce I et al. Low serum cholesteryl ester-docosahexaenoic acid levels in Alzheimer’s disease: a case-control study. British Journal of Nutrition 2003;89:483-489.
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