Excerpt From Dennis N Crouse’s book Prevent Alzheimer’s Autism and Stroke with 7 Supplements, 7 Lifestyle Choices and a dissolved Mineral

Appendix VI

Epidemiology Supporting Aluminum’s Causal Role in Alzheimer’s Disease

Epidemiological studies comparing the level of aluminum in drinking water to the relative risk of Alzheimer’s disease support the contention that aluminum is a causal factor of Alzheimer’s disease. Using epidemiology studies to find correlations between aluminum ingestion and Alzheimer’s disease has been made difficult because there are many sources of aluminum in the human diet. Therefore it is surprising that correlations have been found between aluminum in drinking water and AD or dementia in the 7 largest epidemiology studies each involving more than 300 people with AD or dementia. The reason for this may be because aluminum in drinking water is more easily absorbed by the gastrointestinal tract than aluminum in food. It has been found that 0.3% of the aluminum in drinking water is absorbed, while only 0.1-0.2% of the aluminum in food is absorbed391.

 

Epidemiology studies are only valid if the number of people with AD and/or dementia in the study is high enough to make the data statistically significant. Therefore the 13 epidemiology studies in the following table are listed in order of number of AD and/or dementia cases evaluated in each study. Note that there are 7 studies involving 300 or more cases of AD or dementia and all 7 of these studies found a greater risk of AD or dementia due to drinking water with higher aluminum levels. There are 6 studies involving approximately 100 or less cases of AD or dementia. With such a low number of cases it is not surprising that four of these studies (e.g. studies 8, 9, 12, and 13) found no statistically significant (NSS) relationship between aluminum in drinking water and the incidence of AD, dementia, or low cognition. For more details on these four studies see the notes at the end of the table.

Notes on Studies 7, 8, 9, 12, and 13

 

· Studies 7 (1989) and 8 (1997) were both carried out by the same group at South Hampton Hospital and published with the same lead author (e.g. C. N. Martyn)80,697. The positive correlation between high aluminum levels in drinking water and AD this group reported eight years earlier in study 7 was described and not retracted in study 8. With 200 fewer AD cases in study 8, they were unsuccessful in finding any correlation between high aluminum levels in drinking water and AD697. Seventy percent of the controls in study 8 were people with dementias and neurologic disorders, other than AD. The authors of study 8 point out that aluminum could also influence the course of these diseases in the controls resulting in a systematic error in study 8. In fact, in study 7 they reported a higher relative risk (e.g. 1.1 - 1.2) of dementias, other than AD, in men 40-64 years of age exposed to aluminum levels in drinking water over 20mcg/liter80.

 

· In study 9 only 4 cases of AD had been exposed to greater than 100mcg/liter of aluminum426.

 

· In study 12 the participants only drank water with less that 100mcg/liter of aluminum701.

 

· In study 13 elevated aluminum in drinking water was only ingested for 3 years79,702.

 

Conclusion

In Chapter 1 of this book Hill’s criteria was used to show that aluminum is a causal factor for AD. Epidemiological data supports both the strength and consistency of association between aluminum and AD. These two criteria are part of Hill’s nine criteria for causality. From the results of the 7 largest epidemiology studies we can conclude, as did the World Health Organization, that “The positive relationship between aluminum in drinking-water and AD … cannot be totally dismissed”83. Based upon this epidemiological data the World Health Organization recommended a maximum of 100mcg/liter of aluminum in drinking water in 1998 and 200383

 

 

79. Flaten, T.P.; Aluminum as a risk factor in Alzheimer’s disease, with emphasis on drinking water; Brain Res. Bull.; May; 55(2):187-96 (2001)

80. Martyn, C.N., et al.; Geographic relation between Alzheimer’s disease and aluminum in drinking water; Lancet, 1:59-62 (1989)

81. Flaten, T.P.;  Geographical associations between aluminum in drinking water and death rates with dementia (including Alzheimer’s disease),Parkinson’s disease and amyotrophic lateral sclerosis in Norway; Environ. Geochem. Health; 12:152-167 (1990)

82. Neri, L.C., and Hewitt, D.; Aluminum, Alzheimer’s disease, and drinking water; Lancet 338:390, (1991)

692. Flaten, T.P.; An investigation of the chemical composition of Norwegian drinking water and its possible relationships with the epidemiology of some diseases. Dept. of Chem.; Norwegian Univ. Sci. and Tech., Trondheim, Norway (1986)

693. Vogt, T.; Water quality and health: Study of a possible relation between aluminum in drinking water and dementia. Sosiale og Okonomiske Studier no. 61. Oslo: Statistics Norway (1986)

694. Forbes, W.F., et al.;  Geochemical risk factors for mental functioning, based upon the Ontario Longitudinal Study of Aging (LSA) V. Comparison of the results, relevant to aluminum water concentrations, obtained from LSA and death certificates mentioning dementia; Can. J. Aging; 14:642-56 (1995)

695. Canadian Study of Health and Aging Group; The incidence of dementia in Canada in 1991; Neurology; July; 55(1):66-73 (2000)

696. Forbes, W.F., and Agwani, N.; Geochemical risk factors for mental functioning, based upon the Ontario Longitudinal Study of Aging (LSA) III. The effects of aluminum-containing compounds; Aging 13:488-98 (1994)

697. Martyn, C.N., et al.; Aluminum concentrations in drinking water and risk of Alzheimer’s disease; Epidemiology; 8:281-86 (1997)

698. Forster, D.P., et al.; Risk factors in clinically diagnosed presenile dementia of the Alzheimer’s type: A case-control study in northern England; J. Epidemiol. Community Health; 49:253-58 (1995)

699. Frecker, M.F.; Dementia in Newfoundland: identification of a geographical isolate?; J. Epidemiol. Community Health; 45:307-11 (1991)

700. Doll, R.; Review: Alzheimer’s disease and environmental aluminum; Age Aging; 22:138-53 (1993)

701. Wettstein, A.; et al.; Failure to find a relationship between mnestic skills of octogenarians and aluminum in drinking water; Int. Arch. Occup. Environ Health 63:97-103 (1991)

702.  Wood, D.J., et al.; Bone mass and dementia in hip fracture patients from areas with different aluminum concentrations in water supplies; Age Aging; 17:415-19 (1988)