So, in this modern society we have a growing number of products being marketed to help counter age-related cognitive decline, deficits in brain circulation and cognitive health in general. But, what is it that is setting us up for memory difficulties and other cognitive issues, especially as we get older? What are those issues that set us up for Parkinson’s disease, vascular dementia, Alzheimer’s disease, Lou Gehrig’s disease and other related conditions? The fact is that some people groups do not suffer from these conditions, and perhaps we need to learn something from them. In this research update we will discuss some lifestyle issues that are relevant to brain disease prevention. Risk Factors for Alzheimer’s Disease (AD) 

Most cases of Alzheimer’s disease are prompted by one or more identifiable risk factors including obesity, high homocysteine levels, depression, high blood pressure, narrowing of the carotid arteries and among certain groups, smoking and type II diabetes. Most of these risk factors are under your control, and so everyone has an opportunity to take steps to help prevent the disease. Another identifiable risk factor for both Alzheimer’s and Parkinson’s disease is a sedentary lifestyle, the level of physical activity. Getting out and being physically active is a crucial issue in the maintenance of brain health. Being physically active, especially when combined with an optimal, plant-based eating plan, helps prevent heart disease, diabetes, high blood pressure, stroke, Parkinson’s disease and dementia. A third study that looked at data from European institutions found that there recently has been a decreased incidence of cardiovascular risk factors in Western Europe, which are strongly related to the occurrence of dementia; their data indicate that attention to optimum lifestyle is essential to guarantee cognitive health late in life and suggest that current research should focus more on primary prevention.  A fourth source discusses interesting differences between men and women and incidence of Alzheimer’s disease. There appears to be differences in lifestyle vulnerabilities between men and women with women having greater than one in six chance of developing Alzheimer’s disease compared with a one in 11 chance for men. The lifestyle issues that increase vulnerability include lack of exercise, poor diet and obesity, diabetes and hypertension, smoking and excess alcohol, and lack of cognitive reserve. This cognitive reserve issue is interesting; the degree of mental stimulation a person experiences over a lifetime is linked to the amount of cognitive reserve the brain builds up to help resist the development of Alzheimer’s disease. The larger this cognitive reserve, the better the  individual can tolerate brain changes associated with aging and disease without experiencing a loss of function. Compared to  men, women tend to have lower levels of cognitive reserve. Engaging in mentally stimulating activities, learning new information, challenging your mind with multiple experiences, and leading an active social life are all good ways to build or maintain your mental muscles and improve the ability to cope with brain changes. Other sex linked biological factors for women and risk of Alzheimer’s disease include greater longevity among women, menopausal drop in production of brain protective female hormones like estrogen, the genetic risk factor APOE4, a faster rate of decline among women with mild cognitive impairment, greater vulnerability among older women to the effects of general anesthesia, and a greater incidence of diabetes among women. And, men also have unique biological vulnerabilities to dementia. All men possess an X and Y chromosome; research has revealed that men who lose Y chromosomes from their blood cells as they age are much more likely to develop Alzheimer’s disease than men who do not. This research looked at 3200 male participants who already had Alzheimer’s disease and they were nearly 3 times more likely than healthy participants to have lost the Y chromosome from some of their blood cells. The loss of the Y chromosome was associated with seven times the risk of developing Alzheimer’s disease over eight years. 

REF: 1) Paillard T et al. ‘Protective effects of physical exercise in Alzheimer’s disease and Parkinson’s disease: a narrative review.’  Journal of Clinical Neurology, 2015 Jul. 2) William Zahler, ‘Alzheimers Disease, A Research Update’   3) Wu YT, Fratiglioni L, Matthews FE, Lobo A, et al. ‘Dementia in western Europe: epidemiological evidence and implications for policy making.’ Lancet Neurol. Published online August 20, 2015. 4) Maurizio Fava: ‘Alzheimer’s risk and gender: how do men and women differ?’, Massachusetts General Hospital, mind, mood and memory newsletter, August 2016. 

Mercury and other Toxins in Fish So, the accumulation of methyl-mercury compounds and perhaps other toxins in fish is linked to the onset of depression, a serious common mental disorder responsible for most of the 1 million suicides worldwide every year. We know that mercury in fish can cause neurological damage, such as negative effects on Alzheimer’s disease and Parkinson’s disease, memory loss, and autism as well as depression. And, it may be that the accumulation of multiple toxins and the interaction of these toxins in fish lead to multiple central nervous system deficits; our article about fish on the Wellness Warriors website indicates that farm raised fish pose many contaminants including hormones, antibiotics, chemically synthesized colorants, and vaccines. And, the presence of PCBs, dioxins, DDT and other insecticides such as the insecticide toxaphene may be an affront to the central nervous system, including the brain. It is very important that patients with Alzheimer’s disease, vascular dementia, and Parkinson’s disease do everything possible to avoid neurotoxins. Another study involving a group of well-educated corporate executives who consumed more than three or four servings per month of fish like tuna or snapper found that they experienced about a 5% drop in cognitive function, in executive function as a result. So, if a group of highly functioning healthy adults with ample cognitive reserve experienced a decline in brain function from consuming the fish, what results might a similar level of fish intake among individuals already suffering from cognitive decline have? 

 Ref: 1) A C Tsai et al. ‘Suicide mortality in relation to dietary intake of n-3 and n-6 polyunsaturated fatty acids and fish: equivocal findings from 3 large US cohort studies,’ Am J Epidemiol. 2014. 2) William Zahler: ‘ Fish, ‘‘http://www.mywellnesswarriors.com/food-nutrition/caution-foods/fish/, Online, 2015. 3) Michael Greger: ‘Is Fish “Brain Food” for Older Adults?,’ Published online, June 2016. 

Consumption of Meat: We now have quite consistent research information indicating that diet may be one of the key risk factors for the onset of Alzheimer’s disease. Looking at dietary data from 10countries and assessing disease risk, researchers found that consumption of meat increased disease risk the most, followed by eggs and high-fat dairy. Consumption of fruits, vegetables, and grains reduced the risk of Alzheimer’s disease. It is thought that increased intake of metal ions, such as copper and saturated fat in meat are probable mechanisms for this finding. 

REF: Grant WB. ‘ Using multicountry ecological and observational studies to determine dietary risk factors for Alzheimer's disease.’ J Am Coll Nutr. Published online July 25, 2016. 

Vitamin D deficiency:  Vitamin D deficiency is associated with a substantially increased risk of dementia and Alzheimer's disease in older people. This is a particular concern because of the relatively high incidence of vitamin D deficiency in America.  Adults in a recent study who were moderately deficient in vitamin D had a 53 per cent increased risk of developing dementia of any kind, and the risk increased to 125 per cent in those who were severely deficient. Vitamin D comes from three main sources -- exposure of skin to sunlight, foods such as oily fish, and supplements. Older people's skin can be less efficient at converting sunlight into Vitamin D, making them more likely to be deficient and reliant on other sources. These researchers confirm that vitamin D levels above 50 nmol/L are most strongly associated with good brain health. 

REF: Thomas J. Littlejohns et al. ‘Vitamin D and the risk of dementia and Alzheimer disease.’  Neurology, August 2014. 

Metabolic Syndrome and Dementia:  Recent research indicates that metabolic syndrome, a group of risk factors including high blood sugar and blood pressure and a large waistline, leads to dementia. Researchers followed 1,519 participants with normal cognitive abilities and monitored dementia progression and incidence rates. Those with diabetes, obesity, dyslipidemia, and other cardiovascular disease risk factors were up to four times as likely to develop dementia or experience cognitive decline when compared to those without these risk factors! 

REF: Ng TP, Feng L, Nyunt MSZ, et al. ‘Metabolic syndrome and the risk of mild cognitive impairment and progression to dementia follow-up of the Singapore Longitudinal Ageing Study Cohort,’  JAMA Neurol. Published online February 29, 2016. 

Turmeric: turmeric is a whole plant food, and anti-inflammatory food that has earned much media attention recently for its numerous positive health effects. This spice, found in Curry and yellow mustard may be instrumental in preventing Alzheimer’s and in the treatment of Alzheimer’s also. Some researchers have concluded that turmeric may be a safe treatment of the behavioral and psychological symptoms of dementia in Alzheimer’s patients. This food is just a spice. Curcumin is just one of the hundreds of phytochemicals found in turmeric and it has been used in supplement form to test its efficacy in moderating the complications of Alzheimer’s disease. These tests have failed to show any benefit. The principle here is that the whole food is almost always more effective in correcting health issues than their isolated components in supplement form. Note that those in rural India consume a lot of turmeric and have among the lowest reported prevalence of dementia and Alzheimer’s in the world! Is also important to note that until recently Indians ate meat free and egg free diets which is likely also a core issue in their low incidence of dementia. 

REF: 1) Michael Greger: ‘Can Turmeric Help with Alzheimer’s?’, Published online, April 2016. 2) HutchinsWolfbrandt A, Mistry AM: ‘Dietary turmeric potentially reduces the risk of cancer.’ Asian Pac J Cancer Prev. 2011. 

B Vitamins:  A double-blind randomized controlled trial found that homocysteine-lowering by B vitamins can slow the rate of accelerated brain atrophy in people with mild cognitive impairment. Homocysteine is an amino acid that is produced by the body, usually as a byproduct of consuming meat. As we age, our brain slowly atrophies, but the shrinking is much accelerated in patients suffering from Alzheimer’s disease. Homocysteine is considered a strong, independent risk factor for the development of dementia and Alzheimer’s disease. Having a blood level over 14 may double our risk. In the Framingham Study, they estimated that as many as 1 in 6 Alzheimer’s cases may be attributable to elevated homocysteine in the blood, now thought to play a role in brain damage and cognitive and memory decline. Our body can detoxify homocysteine, though, using three vitamins, folate, vitamin B12, and vitamin B6. 

High levels of vitamin B12 may slow brain aging as demonstrated in a study of 501 participants in Sweden. Those with higher B12 levels decreased the rate at which their brains decreased in volume, whereas those with higher homocysteine levels increased their rate of brain volume decrease. 

REF: 1) G Douaud, H Refsum, C A de Jager, R Jacoby, T E Nichols, S M Smith, A D Smith. ‘Preventing Alzheimer's disease-related gray matter atrophy by B-vitamin treatment.’ Proc Natl Acad Sci U S A. 2013 Jun. 2) Hooshmand B, Mangialasche F, Kalpouzos G, et al. ‘Association of Vitamin B12, folate, and sulfur amino acids with brain magnetic resonance imaging measures in older adults: a longitudinal population-based study.’  JAMA Psychiatry. Published online April 27, 2016.

Omega-3 fatty acids: Alzheimer’s disease and Parkinson’s disease are the two most common neurodegenerative diseases. Omega-3 fatty acids appear to be useful for preventing these diseases. Low omega-3 intake and low levels of DHA in the blood are associated with age-related cognitiv

decline and Alzheimer’s disease. Also, DHA depletion in certain areas of the brain occurs in Alzheimer’s disease. In some studies, low plasma EPA was also associated with risk of dementia or cognitive decline. More recent studies have investigated brain volume, finding that higher blood omega-3 levels are associated with larger brain volumes in older people. This implies that abundant DHA and EPA omega-3 fats could help to prevent brain shrinkage with age. 

REF: Pottala JV, Yaffe K, Robinson JG, et al.’ Higher RBC EPA + DHA corresponds with larger total brain and hippocampal volumes: WHIMS-MRI study.’ Neurology 2014. 

 

Brain Protecting Foods: Nuts and seeds are rich in vitamin E which has been shown to help Alzheimer’s disease. Blueberries in grapes get their deep colors from anthocyanins, powerful antioxidants shown to improve learning and recall. Sweet potatoes are the dietary staple of Okinawans, the longest lived people who are also known for maintaining mental clarity into old age; these potatoes are extremely rich and beta-carotene, a powerful antioxidant. Green leafy vegetables are loaded with folate, an important brain protecting the vitamin. Beans and chickpeas have vitamin B6 and folate as well as protein and calcium. 

REF: Neal Barnard: ‘Power foods for the brain,’ 2013. 

 

A group of researchers has identified 150 genes associated with healthy aging; this is called the ‘healthy age gene score,’ they found that people with a high healthy age gene score showed better cognitive and renal function over a period of 12 years. And, those developing Alzheimer's showed a lower score. This appears to be a new non-invasive diagnostic tool for the early detection of Alzheimer's disease; this might allow early prevention interventions. 

REF: Sood S, Gallagher IJ, Lunnon K, et al. ‘A novel multi-tissue RNA diagnostic of healthy ageing relates to cognitive health status.’ Genome Biol. 2015.