Eiser AR. Prevention of dementia: Integrative Medicine and its differing epistemology Commentary. Am J Med 2020; 133: 407-408.
Author discusses evidence for prevention of dementia that is evidence based, but not with randomized clinical trials and therefore not in clinical guidelines.
The Mediterranean diet and the MIND diet, if followed assiduously, reduce the risk of dementia by over 50 percent. (Morris MC, Tangney CC, Wang YY et al. Alzheimer's dementia 2015; 11: 1007-1014).
A Swedish study show that women who exercise vigorously in middle age have a 65 % reduction in the prevalence of dementia, and that those with a low level have an increased risk of 35 percent. Horder H, Johannson L, Guo X., et al. Midlife cardiovascular fitness and dementia: a 44 year longitudinal population study in women Neurology 2018; 90: e 1298 to 1305.
Use of a sauna in Finland 4 days a week or more was associated with a 66 % reduction in prevalence of dementia compared to those who used it 2 days a week or less. Laukkanen T, Kunutsor S, Kauhanen J, et al. Sauna bathing is inversely associated with dementia and Alzheimer's disease in middle aged Finnish men. Age Aging 2016; 46: 245-249.
In Japan there was a 50 % reduction in in individuals who drank two cups of green tea per day compared to those who did not drink green tea. Kuriyama S, Hozawa A, Ohmori K, et al. Green tea consumption andcognitive function: a cross sectional study from the Tsurugaya project Am J Clin Nutr 2006; 83: 355-61.
Women in the Nurse's Health Study who consumed blueberries or strawberries twice a week had a substantial reduction in cognitive decline (equivalent to two years younger cognitive function compared to non berry consumers, possibly due to anthocyanins in berries that cross the blood brain barrier. Devore EE, Kang JH, Breteler MM, et al. Dietary intakes of berries and flavonoids in relation to cognitive decline. Ann Neurol 2012: 72: 135-43.
The Copenhagen Heart Study, case control, showed a fifty percent risk of dementia in wine drinkers (men and women) even less than daily, whereas beer drinkers had increased risk (Andres-Lacueva C, Shukitt-Hale B, Galli RL, et al. Anthocyanins in aged blueberry- fed rats are found centrallyand may enhance memory. Nutr Neurosci 2005; 8: 111-120. and Truelsen T, Thudium D, Gronbaek M. Amount and type of alcohol and risk of dementia. the Copenhagen City Heart Study Neurology 2002; 59: 1313-1319.
Other risk factors: age, obesity, diabetes, hypertension, gut dysbiosis, impaired immune system liver, or kidney function. Central obesity is associated with twice lifetime risk,diabetes by 70 percent increase in risk. Singh-Manoux A, Dugravot A, Shipley M, et al. Obesity trajectories and risk of dementia: 28 years of followup in the Whitehall II study. Alzheimers Dement 2018; 14: 178-186. and Gudala K, Bansal D. Schifano F et al. Diabetes mellitus and risk of dementia: a meta-analysis of prospective observational studies. J Diabetes Investig 2013; 4: 640-650.
Conclusion: Reliance on industry funded randomized control trials are insufficient .