If Alzheimer’s is a disease related to adverse inflammatory responses over time, could one of the largest and most regular antigenic burden – our foods have a significant impact on risk of development. What level of conviction would we as humans looking at a future of declining cognitive function require to moderate our food selection.
The journal Archives of Neurology in April 2010 published a paper looking at the role of a protective diet over time on the risk of Alzheimer’s development in northern Manhattan, New York.[1]
As humans we are prone to wide food selection and isolated or synergistic combination become complex. To try and resolve a methodological error risk, this group used an alternative strategy called dietary pattern analysis.[2] Instead of looking at individual nutrients or foods, pattern analysis examines the effects of overall diet.
A group of 2,148 older adults (age 65 and older) without dementia living in New York were selected. They provided information about their diets and were assessed for the development of dementia every 1.5 years for an average of four years. Several dietary patterns were identified with varying levels of seven nutrients previously shown to be associated with Alzheimer’s disease risk:
- Saturated fatty acids (-ve)[3]
- Monounsaturated fatty acids (+ve)[4]
- Omega-3 fatty acids 3
- Omega-6 fatty acids 3
- Vitamin E (+ve)[5]
- Vitamin B12 (+ve)[6]
- Folate (+ve)[7]
At entry, a physician elicited each subject’s medical and neurological histories and conducted standardised physical and neurological examinations. Each subject also underwent a structured in-person interview including an assessment of health and function and a neuropsychological battery. A global summary score on the Clinical Dementia Rating (CDR)24 was then assigned.
The group was assessed for age, education, ethnicity, BMI, smoking, calorie intake, and alcohol. Apolipoprotein e4 genotypical analysis was also taken, splitting the groups into those with or without the 1&2 e4 alleles as they are a recognised risk gene for developing Alzheimer’s.[8]
Various additional supplementary analyses was undertaken to exclude confounding factors such as benefits from small alcohol intake or additional nutrients from supplements meaning that from the original 4166 subjects the eventual number were selected.
The foods that demonstrated the greatest benefit were positively correlated with intakes of salad dressing, nuts, fish, tomatoes, poultry, cruciferous vegetables, fruits, and dark and green leafy vegetables (factor loadings ≥0.15) and food related outcomes were negatively correlated with intakes of high-fat dairy, red meat, organ meat, and butter (factor loadings ≤–0.15). This Dietary Pattern reflected a diet rich in {omega}-3 PUFA, {omega}-6 PUFA, vitamin E, and folate, but with lower Saturated Fatty Acid and vitamin B12 .
The nutrient combinations reflect the previously understood role of antioxidant protection, homocysteine metabolism, and better blood sugar control, reducing risk of insulin resistance, fatty acids for vascular circulation benefits and others.
Comment
After looking at the role of foods in reducing inflammation in this post, it was interesting to see the results of this study further supporting the conclusion; dietary patterns that reflect the nutrients required to meet multiple pathways of degeneration, including inflammation has a strongly protective influence against the development of AD.
People who showed the greatest adherence to this dietary pattern were 38% less likely to develop Alzheimer’s disease than those who had the least adherence to this pattern (relative risk 0.62, 95% confidence interval 0.43 to 0.89).
So if planning to contribute a brain related food selection, keep in mind that this study took place over a short time period of just 4 years, plus the participants were already over 65years old – so it really is never too late to start protective food selection.
References
[1] Gu, Y., Nieves, J., Stern, Y., Luchsinger, J., & Scarmeas, N. (2010). Food Combination and Alzheimer Disease Risk: A Protective Diet Archives of Neurology DOI: 10.1001/archneurol.2010.84
[2] Hu FB (2002). Dietary pattern analysis: a new direction in nutritional epidemiology. Current opinion in lipidology, 13 (1), 3-9 PMID: 11790957
[3] Kalmijn S, Launer LJ, Ott A, Witteman JC, Hofman A, & Breteler MM (1997). Dietary fat intake and the risk of incident dementia in the Rotterdam Study. Annals of neurology, 42 (5), 776-82 PMID: 9392577
[4] Solfrizzi V, Colacicco AM, D’Introno A, Capurso C, Torres F, Rizzo C, Capurso A, & Panza F (2006). Dietary intake of unsaturated fatty acids and age-related cognitive decline: a 8.5-year follow-up of the Italian Longitudinal Study on Aging. Neurobiology of aging, 27 (11), 1694-704 PMID: 16256248
[5] Masaki KH, Losonczy KG, Izmirlian G; et al. Association of vitamin E and C supplement use with cognitive function and dementia in elderly men. Neurology. 2000;54(6):1265-1272. View Full Paper
[6] Bryan J, Calvaresi E. Associations between dietary intake of folate and vitamins B-12 and B-6 and self-reported cognitive function and psychological well-being in Australian men and women in midlife. J Nutr Health Aging. 2004;8(4):226-232 View Abstract
[7] Corrada MM, Kawas C, Hallfrisch J, Muller D, Brookmeyer R. Reduced risk of Alzheimer’s disease with high folate intake: the Baltimore Longitudinal Study of Aging. Alzheimers Dement. 2005;1(1):11-18 View Abstract
[8] Martins CA, Oulhaj A, de Jager CA, Williams JH. APOE alleles predict the rate of cognitive decline in Alzheimer disease: a nonlinear model. Neurology. 2005 Dec 27;65(12):1888-93. View Abstract
