Coffee and a healthy diet reduce the risk of Alzheimer’s

August, 2011

Recent studies show why a low-fat, low-carb diet, and caffeinated coffee, help protect against developing Alzheimer’s disease.

Dietary changes affect levels of biomarkers associated with Alzheimer's

In a study involving 20 healthy older adults (mean age 69.3) and 29 older adults who had amnestic mild cognitive impairment (mean age 67.6), half the participants were randomly assigned to a high–saturated fat/high–simple carbohydrate diet (HIGH) and half to a low–saturated fat/low–simple carbohydrate diet (LOW) for four weeks, in order to investigate the effects on biomarkers associated with Alzheimer’s.

For the healthy participants, the LOW diet decreased the level of amyloid-beta 42 in the cerebrospinal fluid, while the HIGH diet increased its level. The HIGH diet also lowered the CSF insulin concentration. For those with aMCI, the LOW diet increased the levels of amyloid-beta 42 and increased the CSF insulin concentration. For both groups, the level of apolipoprotein E in the CSF increased in the LOW diet and decreased in the HIGH diet.

For both groups, the LOW diet improved performance on delayed visual recall tests, but didn’t affect scores on other cognitive measures (bear in mind that the diet was only followed for a month).

The researchers suggest that the different results of the unhealthy diet in participants with aMCI may be due to the diet’s short duration. The fact that diet was bringing about measurable changes in CSF biomarkers so quickly, and that the HIGH diet moved healthy brains in the direction of Alzheimer’s, speaks to the potential of dietary intervention.

Why coffee helps protect against Alzheimer's disease

Support for the value of coffee in decreasing the risk of Alzheimer’s comes from a mouse study, which found that an as yet unidentified ingredient in coffee interacts with caffeine in such a way that blood levels of a growth factor called GCSF (granulocyte colony stimulating factor) increases. GCSF is a substance greatly decreased in patients with Alzheimer's disease and demonstrated to improve memory in Alzheimer's mice.

The finding points to the value of caffeinated coffee, as opposed to decaffeinated coffee or to other sources of caffeine. Moreover, only "drip" coffee was used; the researchers caution that they don’t know whether instant caffeinated coffee would provide the same GCSF response.

There are three ways that GCSF seems to improve memory performance in the Alzheimer's mice: by recruiting stem cells from bone marrow to enter the brain and remove beta-amyloid protein; by increasing the growth of new synapses; by increasing neurogenesis.

The amount of coffee needed to provide this protection, however, is estimated to be about 4 to 5 cups a day. The researchers also believe that this daily coffee intake is best begun at least by middle age (30s – 50s), although starting even in older age does seem to have some protective effect.

Weirdly (I thought), the researchers remarked that "The average American gets most of their daily antioxidants intake through coffee". Perhaps this points more to the defects in their diet than to the wonders of coffee! But the finding is consistent with other research showing an association between moderate consumption of coffee and decreased risk of Parkinson's disease, Type II diabetes and stroke.

A just-completed clinical trial has investigated GCSF treatment to prevent Alzheimer's in patients with mild cognitive impairment, and the results should be known soon.

Reference: 

[2442] Bayer-Carter, J. L., Green P. S., Montine T. J., VanFossen B., Baker L. D., Watson S. G., et al.
(2011).  Diet Intervention and Cerebrospinal Fluid Biomarkers in Amnestic Mild Cognitive Impairment.
Arch Neurol. 68(6), 743 - 752.

Cao, C., Wang, L., Lin, X., Mamcarz, M., Zhang, C., Bai, G., Nong, J., Sussman, S. & Arendash, G.  2011.Caffeine Synergizes with Another Coffee Component to Increase Plasma GCSF: Linkage to Cognitive Benefits in Alzheimer's Mice. Journal of Alzheimer's Disease, 25(2), 323-335.

Related News

A new study finds out why curcumin might help protect against dementia, and links two factors associated with Alzheimer’s and Parkinson’s diseases: DNA damage by reactive oxygen species (ROS), and excessive levels of copper and iron in parts of the brain.

Some epidemiological studies have showed that people who smoke tend to have lower incidences of Parkinson's disease and Alzheimer's disease; this has been widely attributed to nicotine. However, nicotine's harmful effects make it a poor drug candidate.

A study involving 70 older adults (60-83) has found that those with at least ten years of musical training performed the best on cognitive tests, followed by those with one to nine years of musical study, with those with no musical training trailing the field.

A study following 837 people with

Supporting earlier research, a study involving 8,534 older adults (65+; mean age 74.4) has found those who were obese in middle age had almost four times (300%) more risk of developing dementia. Those who were overweight in middle age had a 1.8 times (80%) higher risk of developing dementia.

A study in which mice were exposed to polluted air for three 5-hour sessions a week for 10 weeks, has revealed that such exposure damaged neurons in the

Adding to the growing evidence that social activity helps prevent age-related cognitive decline, a longitudinal study involving 1,138 older adults (mean age 80) has found that those who had the highest levels of social activity (top 10%) experienced only a quarter of the rate of cognitive declin

A study involved 117 older adults (mean age 78) found those at greater risk of coronary artery disease had substantially greater risk for decline in verbal fluency and the ability to ignore irrelevant information. Verbal memory was not affected.

A study involving 200 older adults (70+) experiencing a stay in hospital has found that at discharge nearly a third (31.5%) had previously unrecognized low cognitive function (scoring below 25 on the MMSE if high-school-educated, or below 18 if not).

From the Whitehall II study, data involving 5431 older participants (45-69 at baseline) has revealed a significant effect of midlife sleep changes on later cognitive function. Sleep duration was assessed at one point between 1997 and 1999, and again between 2002 and 2004.

Pages

Subscribe to Latest newsSubscribe to Latest newsSubscribe to Latest health newsSubscribe to Latest news
Error | About memory

Error

The website encountered an unexpected error. Please try again later.