Diet and Dementia: Approaches to Risk-Minimisation through Nutrition and Lifestyle Management of Neurodegenerative Diseases.

My gorgeous and loving Father. Alzheimer's.

Introduction

Dementia is characterized as an irreversible progressive decline in the ability to remember, learn, understand and communicate (Coppedé et al. 2012, Ramirez-Bermudez 2012). Alzheimer’s disease is by far the most common form of dementia in the elderly, with other dementia types including vascular dementia (usually resulting from minor strokes), dementia with Lewy bodies, and dementia associated with conditions like Huntington’s and Parkinson’s disease (Philpott 2014).

Currently over 46 million people worldwide are living with dementia, with the numbers expected to double by 2030, and reach 131.5 million by 2050 (Prince et al. 2015), primarily as a result of increased life-span expectancy in developed and developing countries (Brookmeyer et al. 2007).

Despite a vast number of randomized controlled trials involving single-nutrient nutrition interventions (Alves et al. 2013, Van der Zwaluw et al. 2014, Ngandu et al. 2015), Alzheimer’s Disease International’s Review of Nutrition and Dementia Research found no clear evidence to support a protective or curative effect of the various individual nutrients focused on by current and recent research (Philpott 2014). Following, a ‘whole diet’ paradigm is beginning to dominate in nutritional epidemiology (Valls-Pedret et al. 2013). Although cost-effective and easy to implement (Saulle, Seymyonov and la Torre 2013), the shift in methodology to include non-biomedical parameters makes clinical meaningfulness and the hierarchy of supporting evidence difficult to establish and controversial within the research community.

With methodological issues and a consensus that future trials and research establish more cohesive parameters (Morris 2016), newer epidemiological approaches to “whole diet/whole person” intervention, as well as alternative assumptive frameworks and cognitive models are now questioning whether the “hierarchy of evidence”(used to create relevant dietary guidelines), giving greatest weight to randomized controlled trials, is definitively the best choice for addressing the complexity of human diet and health relationships (Hassel 2014).

Whole diet strategies (The Mediterranean Diet), the gut microbiome, epigenetics and a concert of psychosocial interventions offer alternative multi-disciplinary models to the complex study of relationships between food ingestion and neurological degeneration. These strategies accept as a central tenet that dementia may not just be a matter of a technical fix with targeted pharmaceuticals, but is instead a complex social, psychological, medical, nutritional, ethical and spiritual condition (Hughes 2011) that may defy deterministic cause/effect paradigms.

Dietary approaches to prevention.

In the early 1950’s Ancel Keys observed that the poor populations of small towns in Crete and Southern Italy were much healthier than the wealthy citizens of New York. He theorized that this was due to their simple, fresh and regional/traditional dietary choices and went on to scientifically prove the nutritional value of this ‘Mediterranean Diet’ in the famous “Seven Countries Study” (Wright 2011).

The diet is dominated by consumption of plant foods (vegetables, fruits, legumes and cereals) and olive oil, a moderate intake of fish, a low to moderate use of dairy products (mostly goat-milk derived), low consumption of meat and poultry, very little saturated fat and wine consumed in low to moderate amounts, usually with a meal (Willett et al. 1995). This “whole diet” framework encompasses beneficial levels of specific micronutrients associated with protection against cognitive decline and aging such as Vitamin E, vitamin B12, folate, choline and Vitamin C (Morris 2012, Perez et al. 2012, Meck et al. 2007, Caudill 2010).

This food combination’s cited biological basis for physical benefit lies in a decrease in oxidative stress, inflammation and vascular disease, -all recognised as valid participants in the pathophysiology of neurodegenerative disease (Féart et al. 2009, Morris 2012, Perez et al. 2012). Strict adherence to the diet may lower the risk of Alzheimer’s by as much as 50% (Liu et al. 2010), although its beneficial effects are more likely during the long prodromal phase of dementia, rather than in the years immediately preceding diagnosis.

One of the least studied but most fascinating components of the Mediterranean diet is its very nature. We know its basic food-parameters, -for example, ‘high consumption of plant foods’ (Morris 2012), but what does this mean? Do the ‘plant foods’ themselves contribute more than we suspected beyond general health parameters?

The traditional Mediterranean diet is characterized by certain food combinations that have an over-arching theme: Fresh, seasonal, local, accessible and economically affordable (Gerber & Hoffman 2015). It was a diet adjusted to the cultural, climatic and environmental characteristics of the region and its people (Naska & Trichopolou 2014), and included not only the extensively studied Virgin Olive Oil (Hoffman & Gerber 2014, Servili et al. 2014) but an extraordinary variety of wild plant and animal foods.

Wild greens for example, were a winter staple. They start growing after a good autumn rainfall and are mostly available up until early summer when more traditional cultivated vegetable crops became available (Dymiotis 2015). An enormous variety of wild plant foods were regularly harvested by women and children and are the central feature in many iconic regional dishes (Kochilas 2016). The harvesting itself requiring cardiovascular exercise and sunlight exposure. Many, if not all of these wild foods provided not only caloric nutrition, but an enormous range of pharmacological benefits. Greens in common use included: Bitter dock (Rumex obtusifolius), Arugula (Eruca sativa), Black bryony (Tamus communis), Blue Mallow (Malva silvestris), Golden thistle (Scolymus), Garden cress (Lepidium sativum L.), Grass Lily (Ornithogalum), Nettles (Urtica dioica), Purslane (Portulaca oleracea L.), Wild Fennel (Foeniculum vulgare) and Yellow salsify (Tragopogon) (Kochilas 2016).

Blue Mallow (Malva silvestris) for example is well documented as a potent periodontal disease inhibitor, which itself is related to many systemic diseases known as contributing markers to Alzheimer’s (including cardiovascular disease and diabetes) (Benso et al. 2015, Negrato et al. 2013, Rautemaa et al. 2007). Purslane (Portulaca oleracea L.) contains pancreatic lipase inhibitors, reduces triglycerides, LDL-cholesterol, vascular tension and systolic blood pressure (Lee et al. 2012, Farzei et al. 2015). Nettles (Urtica dioica) are a rich source of minerals and essential elements like Calcium, Magnesium, Iron, Manganese, Zinc, and copper (Mahlangeni, Moodley & Joannalagadda 2015).

The use of local, seasonal, minimally processed foods is not exclusive to the Mediterranean Diet, and has been observed in numerous societies to promote healthful longevity and minimise the neurological degeneration associated with aging. Buettner’s ‘Blue Zones’ exhibit this dietary pattern (Carter 2015) as did the Okinawan’s made famous in 2001 for their extraordinary longevity and freedom from disease (Willcox, Willcox & Suzuki 2001). Indeed, the human species has created a huge diversity of uninvestigated non-biomedical models for understanding diet and health. Cross-cultural engagement (Hassel 2005, 2006) could be utilised to a much greater extent in seeking out traditional food and health understandings that developed beyond the scope and a priori of biomedical science. The first American Pharmacopeia, published in 1820 listed more than 200 food-medicines coming from indigenous inhabitants (Moerman 1998). Although these food cures and medicines come from a different cognitive orientation that do not share the rigid subject/object separation of Western biomedicine, they were nonetheless developed with a rigorous empiricism (Elk 2016) that seems foolish to dismiss ‘out of hand’ as non-scientific.  The well-researched health benefits of minimally processed plant food diets utilized by so many cultures exhibiting exceptional longevity and physical/mental health are also beginning to gain traction within the mainstream medical communities, with plant-based dietary medicine being offered in Hospital residency programmes (Kamila 2016).

In addition to these concerns, we are now also presented with new research on the gut microbiome and epigenetics, and their influence on neurological processes. Although research is in its infancy, it appears that what we ingest and the resulting composition and expression of the gut microbiome has pronounced effects on both mood and behaviour (Cryan & Dinan 2012, Mayer et al. 2014). Recent research has linked microbial dysbiosis to neurological disorders like Parkinson’s and Alzheimer’s Diseases with disruptions in bacterial populations of Clostridia, Bacteriodetes and Verrucomicrobia implicated particularly for Alzheimer’s disease (Ghaisas, Maher & Kanthasamy 2016). In support of the aforementioned plant-based diet, it has been found that a diet rich in complex carbohydrates, fermented vegetables and pre-biotic containing foods decrease toxin-producing bacteria and increase beneficial bacteria in the gut microbiome (Hvistendahl 2012). With 70% of genes that code for health and longevity under epigenetic control, Dr Perlmutter of the University of Michigan, Miller School of Medicine says that when it comes to physical and mental health, Hippocrates was right: “Let food be your medicine and medicine be your food” (Perlmutter 2015).

 Prevention through nutrition is only one part of the complex human puzzle that is neurodegenerative disease, and despite the encouraging findings of many epidemiological studies in dietary intervention and the support of published Dieticians and Nutritionists (Campbell 2013, Jacobs & Tapsell 2013, Slavin 2012), the clinical meaningfulness of such findings remains controversial within medical science, with supporting evidence cited as ‘weak’ and further studies required before these approaches can be supported as recommendations (Richard et al. 2012, Valls-Pedret & Ros 2013, Canevelli et al. 2016). What is certain, is that despite “magic bullet” thinking still very much apparent in mainstream media nutrition reporting (‘Best Odds Diet to beat Dementia’, The London Sun, 2016), as each individual that develops dementia is unique, so will be the optimal ‘preventive’ diet pattern. Equally, as individuals are comprised of far more than a digestive system, a multi-disciplinary approach to dementia care and prevention is essential (Wolfs et al. 2008).

Lifestyle management, nutrition and care: Living with dementia

‘Cures may emerge; but they should do so against the fundamental background of solicitude’

                                                                                                                    (Hughes 2011)

People with dementia, and indeed any cognitive disorder are as different from each other in likes, needs, memories, culture, beliefs and world-views as any other human being. Reducing behavioural aspects of neurodegeneration to merely ‘disease symptoms’ engenders a depersonalisation that adversely affects therapeutic intervention (Barak 2014). Unfortunately, traditional nursing home structures and practises all too often contribute to this depersonalisation leading to sub-optimal or even unacceptable patient outcomes (Alfredson & Annerstedt 1994, Boekharts et al. 2009).

Recent figures estimate that 85% of patients with advanced dementia have eating difficulties, and that the six-month mortality for such patients is almost 40% (Lam & Lam 2014). Despite these sobering estimates, Australian aged-care residential facilities spend an average of only $9.07 per person, per day on ‘food costs, a figure that incorporates consumables, cutlery, crockery and supplements (Rowe 2014). Nutrition and appetite decline with age, usually accompanied by weight loss (Perez et al. 2012), and in advanced dementia feeding problems can become critical, requiring families and physicians to assess the risks and benefits of artificial (tube) nutrition and hydration.  Up to one third of nursing home residents with advanced cognitive impairment are currently fed with feeding-tubes (Sherman 2003) despite tube feeding being associated with agitation, increased use of restraints and worsening pressure ulcers (Lam & Lam 2014).

One of the key findings in the recent review of nutrition and dementia by Alzheimer’s Disease International was that the eating environment in aged care facilities had a substantial impact on appetite stimulation and food intake. Smaller, well-lit dining rooms decorated in warm, cheerful colours including side-boards and objects d'art were associated with increased food intake and reduced agitation (Philpott 2014), as was a dining area linked to a kitchen that allowed food preparation sounds and smells to cue meal times and stimulate appetite. Familiar, relaxing background music was also linked to increased calorie consumption. A substantial body of research also demonstrated that interacting with food via gardening-based interventions enhances emotional well-being, social function and improved physical health parameters (Clatworth, Hinds & Camic 2013). In short, people are happier and more likely to eat according to their needs in an environment that reflects ‘home’.

Australia’s answer to ‘Mrs Caldicot’ (Arrow Film Distributors 2002), Maggie Beer along with Brisbane-based dietician Cherie Hugo and Flinders University are currently utilising these findings in a series of ‘test case’ aged care homes in South Australia. Through the Maggie Beer-A Good Food Life for All foundation (established in April 2014), they aim to benchmark best practise in Australia and develop a framework for aged-care homes to provide flavoursome, nutritious meals that foster an enjoyment of food, from garden to plate (Rowe 2014). Internationally, Geriatrician William H. Thomas has established more than 100 ‘Green House Projects’ with similar objectives. Thomas’s facilities focus on the natural rhythms of the day and not the staff’s tasks.

“Most of them are serving life sentences, stripped of privacy, independence and choice. The fact that so many people, whose only crime is frailty, are confined in this way is powerful evidence that we live in a deeply ageist society”  (pp 3, Drevitch 2012).

 ‘Patients’ are titled ‘Elders’ and afforded the respect and courtesies that accompany the new nomenclature. Meal times are not determined by management, but by the individual’s personal sleep/wake and hunger cues (Drevitch 2012). Neither initiative will tolerate the serving of ‘eggs that bounce’! (Morgan-Jones 2014).

Conclusions

Whether promoting continued research into biomedical models of dietary prevention strategies, adopting alternative cognitive frameworks embracing non-Western approaches to diet and disease or addressing the quality and systems-based nutrition interventions of people with dementia, Dieticians and Nutritionists have a crucial role in the future directions of dementia care both in Australia and as part of the International community. As new research and initiatives continue to emerge, it is essential that nutrition professionals continue to embrace a broader definition of both ‘disease’ and ‘care’, and to continue to recognise the rich tapestry of ‘person’ beyond disease.

REFERENCES

Alfredson, B.B. & Annerstedt, L. (1994). Staff attitudes and job satisfaction in the care of demented elderly people: group living compared with long-term care institutions. Journal of Advanced Nursing, 20. 964-974

Alves, C.R.R., Merege Filho, C.A.A., Benalti, F.B., Brucki, S….Gualano,B. (2013). Creatine supplementation associated or not with strength training upon emotional and cognitive measures in older women. A randomised double-blind study. PLoSONE, 8. E76301

Barak, Y. (2014). Neurodegenerative Diseases –Laboratory and Clinical Research: Preventing Alzheimer’s Disease– Personal Responsibility: Personal Responsibility. Hauppauge, US; Nova. Retrieved from http://www.ebrary.com.ezyproxy.csu.edu.au

Benso, B., Rosalen, P.L., Alencar, S.M., Murata, R.M. (2015). Malva sylvestris Inhibits Inflammatory Response in Oral Human Cells. An In Vitro Infection Model. PLosONE, Oct 19. 2015. DOI: http://dx.doi.org/10.1371/journal.pone.0140331

Boekharts, S., Depla, M.F.I.A., De Lange, J., Pot, A.M., Eefsting, J. (2009). The effects of group living homes on older people with dementia: a comparison with traditional nursing care. International Journal of Geriatric Psychiatry, 24. 970-978

Brookmeyer, R., Johnson, E., Ziegler-Graham, K. & Arrighi, H.M. (2007). Forecasting the global burden of Alzheimer’s Disease. Alzheimer’s and Dementia, 3(3). 186-191

Canevelli, M., Lucchini, F., Quarata, F., Bruno, G. & Cesari, M. (2016). Nutrition and dementia” Evidence for preventive approaches? Nutrients, 8(3). 144. Retrieved from http://serach.proquest.com.ezproxy.csu.edu.au/docview.1802750487?accountid=10344

Campbell, T.C. (2013). Whole. Rethinking the science of nutrition: BenBella Books, Inc. Retrieved from http://www.ebrary.com.ezproxy.csu.edu.au

Carter, E.D. (2015). Making the Blue Zones: Neoliberalism and nudges in public health promotion. Social Science and Medicine, 133. 374-382. DOI: 10.1016/j.socscimed.2015.01.019

Caudill, M.A. (2010). Pre- and postnatal health: evidence of increased choline needs. Journal of the American Dietetic Association, 110(8). 1198-1206

Clatworth, J., Hinds, J. & Camic, P.M. (2013). Gardening as a mental health intervention: a review. The Mental Health Review, 18(4). 214-225. DOI: http://dx/doi.org.ezproxy.csu.edu.au/10.1108/MHRJ-02-2013-0007

Coppedé, F., Bosco, P., Fuso, A., & Traen, A.M. (2012). Nutrition and Dementia. Current Gerontology and Geriatrics Research, 2012(2012). Article ID: 9260832. DOI: 10.1155/2012/926-82

Cryan, J.F., & Dinan, T.G. (2012). Mind-altering microorganisms: the impact of the gut microbiota on brain and behaviour. Nature Reviews neuroscience, 13. P 701. DOI: 10.1038/nrh.3346

Drevitch, G. (2012). Not Your Father’s Nursing Home: A Visit to the Urban Green House. September 21, 2012. www.nextavenue.org/not-your-fathers-nursing-home-visit-urban-green-house-O/

Dymiotis, M. (2015). www.markdymiotis.com/food/wild-greens/wild-greens-2/

Elk, L.B. (2016). Native Science: Understanding and Respecting Other Ways of Thinking. Rangelands, 38(1). 3-4. DOI: 10.1016/j.rala.2015.il.003

Farzei, M.H., Roja, R., Farzei, F., Abdollahi, M. (2015). Traditional Medicinal Herbs for the Management of Diabetes and its Complications: An Evidence-Based Review. International Journal of Pharmacology, 11(7). 874-877

Féart, C., Samieri, C., Allés, B., Barberger-Gateau, P. (2012). Potential benefits of adherence to the Mediterranean diet on cognitive health. Proceedings of the Nutrition Society, 72. 140-152. DOI: 10.1017/S0029665112002959

Gerber, M. & Hoffman, R. (2015). The Mediterranean Diet: health, science and society. British Journal of Nutrition, 113. S4-S10. DOI: 10.1017/S0007114514003912

Ghaisas, S., Maher, J. & Kanthasamy, A. (2016). Gut microbiome in health and disease: Linking the microbiome-gut-brain axis and environmental factors in the pathogenesis of systemic and neurodegenerative diseases. Pharmacology and Therapeutics, 158. 52-62. DOI: 10.1016/j.pharmthera.2015.11.012

Hassel, C. (2005). The craft of cross-cultural engagement. Journal of Extension, 43(6). www.joe.org/joe/2005december/a1.php

Hassel, C.A. (2006). Woodlands Wisdom: A Nutrition Program Interfacing Indigenous and Biomedical Epistemologies. Journal of Nutrition Education and Behaviour, 38(2). 114-120. DOI: 10.1016/j.jneb.2005.11.033

Hassel, C. (2014). Reconsidering nutrition science: critical reflection with a cultural lens. Nutrition Journal, 13(42). DOI: 10.1186/1475-2891-13-42

Hughes, J.C. (2011). What do people with dementia and their carers really need? Neurodegenerative Disease Management, 1(1). 37-42. DOI: http://dx.doi.org.ezproxy.csu.edu.au/10.2217.nmt.11.3

Hoffman, R. & Gerber, M. (2014). Can rapeseed oil replace olive oil as part of a Mediterranean style diet? British Journal of Nutrition, 112(11). 1992-1895. DOI: 10.1017/S0007114514002888

Hvistendahl, M. (2012). My microbiome and me. Science, 336(6086). 1248-1250. DOI: 10.1126/science.336.6086.1248

Jacobs, D.R. & Tapsell, L.C. (2013). Food Synergy: The key to a healthy diet. The Proceedings of the Nutrition Society, 72(2). 200-206. DOI: 10.1017/S0029665112005011

Kamila, A.Y. (2016). Maine med plants seeds for doctors to focus on health impact of food. Portland Press Herald. April 14, 2016. www.pressherald.com/2016/04/13/vegetarian-kitchen-maine-med-plants-seeds-for-doctors-to-focus-on-health-impact-of-food/

Kochilas, D. (2016). www.dianekochilas.com/glossary-of-edible-wild-greens-2/

Lam, R.E. & Lam, P.J. (2014). Nutrition in dementia. Canadian Medical Association Journal, 186(17). 1319-1320

Lee, A.S., Lee, Y.J., Lee, S.M., Yoon, J.J., Kim, J.S., Kang, D.G., Lee, H.S. (2012). Portulaca oleracea ameliorates diabetic vascular inflammation and endothelial dysfunction in db/db mice. Evidence-Based Complementary and Alternative Medicine, 2012. Article ID: 741824, 9 pages. http://dx.doi.org/10.1155/2012/741824

Liu Y., Nieves, J.W., Stem, Y., Luchsingen, J.A., Scarmeas, N. (2010). Food combination and Alzheimer’s disease risk: a protective diet. Archives of Neurology, 67. 699-706

The London Sun. 2016. April 26. Best Odds Diet to Beat Dementia. [scot region]. Retrieved from http://search.proquest.com.ezproxy.csu.edu.au/docview/1784028946?accountid=10344

Mahlangeni, N.T., Moodley, R. & Jonnalagadda, S.B. (2015). The distribution of macronutrients, antinutrients and essential elements in nettles, Laportea peduncularis susp.peduncularis (River nettle) and Urtica dioica (Stinging nettle). Journal of Environmental Science and Health, 51(3). DOI: 10.1080/03601234.2015.1108806

Mayer, E.A., Knight, R., Mazmanian, S.K., Cryan, J.F., Tilisch, K. (2014). Gut Microbes and the Brain: Paradigm Shift in Neuroscience. The Journal of Neuroscience, 34(46). 15490-15496. DOI: 10.1523/JNEUROSCI.3299-14.2014

Meck, W.H., Williams, C.L., Cermak, J.M. & Blusztajn, J.K. (2007). Developmental periods of choline sensitivity provide an antogenic mechanism for regulating memory capacity and age-related dementia. Frontiers in Integrative Neuroscience, 1(7). 1198-1206

Moerman, D. (1998). Native American Ethnobotany. Portland. Timber Press

Morgan-Jones, P. (2014). Don’t give me eggs that bounce! HammondCare media. Australia.

Morris, M.C. (2012). Nutritional determinants of cognitive aging and dementia. Proceedings of the Nutrition Society, 71(1). 1-13

Morris, M.C. (2016). Nutrition and risk of dementia: overview and methodological issues. Annals of the New York Academy of Sciences, 1367. 31-37. DOI: 10.1111/nyas.13047

Mrs Caldicot’s Cabbage War (2002). Arrow Film Distributors. United Kingdom. https://en.wikipedia.org/wiki/Mrs-Caldicot%27s_Cabbage_War.

Naska, A. & Trichopolou, A. (2014). Back to the future: The Mediterranean diet paradigm. Nutrition, Metabolism and Cardiovascular Diseases, 24(3). 216-219. DOI: 10.1016/j.numecd.2013.11.007

Negrato, C.A., Tarzia, O., Jovanovič, L., Chinellato, L.E. (2013). Periodontal disease and diabetes mellitus. Journal of Applied Oral Science, 21(1). 1-12. DOI: 10.1590/1678-7757201302106

Ngandu, T., Lehtisalo, J., Solomon, A., Levalahti, E. … Laatikainen, T. (2015). A 2 year multidomain intervention of diet, exercise, cognitive training, and vascular risk monitoring versus control to prevent cognitive decline in at-risk elderly people (FINGER): A randomised controlled trial. Lancet, 385. 2255-2263

Perez, L., Heim, L., Sherzai, A., Jaceldo-Siegl, K., Sherzi, A. (2012). Nutrition and vascular dementia. Journal of Nutrition, Health and Aging, 16(4). 319-324

Perlmutter, D. (2013). Epigenetics as Fuel for Brain Health. Alternative and Complementary Therapies, 19(1). 9-12. DOI: 10.1089/act.2013.19103

Philpott, G. (2014). Nutrition and Dementia: Pooling Global Knowledge. INsite, 8(6). 14-15. www.insitemagazine.co.nz/issues/august-2014/nutrition-and-dementia-pooling-global-knowledge/#.V6fngbh96Uk. Accessed 08.08.2016

Prince, M., Wimo, A., Guerchet, M., Ali, G.C., Wu, Y., Prina, M. (2015). World Alzheimer Report, 2015. The Global Impact of Dementia: An Analysis of prevalence, Incidence, Cost and Trends. Alzheimer’s Disease International (ADI), London. https://www.alz.co.uk/research/WorldAlzheimerReport2015.pdf Accessed 08.08.2016

Ramirez-Bermudez, J. (2012). Alzheimer’s Disease: Critical Notes on the History of a Medical Concept. Archives of Medical Research, 43(8). 592-599. DOI: 10.1016/j.arcmed.2012.11.008

Rautemaa, R., Lauhio, A., Cullinan, M.P., Seymour, G.J. (2007). Oral Infections and systemic disease –an emerging problem in medicine. Clinical Microbiology and Infection, 13(11). 1041-1047. DOI: 10.1111/j.1469-0691.2007.01802.x

Rowe, M. (2014). Maggie Beer’s campaign to improve the meals in aged-care homes. The Australian, July 5, 2014. www.theaustralian.com.au/archive/executive-living/maggie-beers-campaign-to-improve-the-meals-agedcare-homes/news-story/C6d64dc761698836ecacf300ce1e6603

Saulle, R., Seymyonov, L., La Torre, G. (2013). Cost and cost-effectiveness of the Mediterranean Diet: Results of a systematic review. Nutrients, 5(11). 4566-4586. DOI: 10.3390/nu.5114566

Servili. M., Sordini, B., Esposto, S., Urbani, S. … Taticchi, A. (2014). Biological Activities of Phenolic Compounds of Extra Virgin Olive Oil. Antioxidants, 3(1). 1-23. DOI: 10.3390/antiox3010001

Sherman, F.T. (2003). Nutrition in advanced dementia. Geriatrics, 58(1). 11-12.

Slavin, J. (2012). Dietary Guidelines: Are we on the right path? Nutrition Today, 47(5). 245-251. DOI: 10.1097/NT.0b013c31826c50af

Van der Zwaluw, N.L., van de Rest, O., Tieland, M., Adam, J.J., Hiddink, G.J., van Loon, L.J.C., de Groot, L.C. (2014). The impact of protein supplementation on cognitive performance in frail elderly. European Journal of Nutrition, 53. 803-812

Willett, W.C., Sacks, F., Trichopolou, A., Drescher, G. & Al, E. (1995). Mediterranean diet pyramid: A cultural model for healthy eating. The American Journal of Clinical Nutrition, 61(6). Retrieved from http://serach.proquest.com.ezproxy.csu.edu.au/docview/231918341?accountid=10344

Wolfs, C.A.G, Kessels, A., Dirksen, C.D., Severens, J.L. & Verhey, F.R.J. (2008). Integrated multidisciplinary diagnostic approach for dementia care: randomised controlled trial. The British Journal of Psychiatry, 192(4). 300-305. DOI: 10.1192/bjp.bp.107.035204

Wright, C.M (2011). Biographical notes on Ancel Keys and Salim Yusuf: origins and significance of the Seven Countries Study and the INTERHEART Study. Journal of Clinical Lipidology, 5(6). 434-440. DOI: 10.1016/j/jcd.2011.09.003

Willcox, B., Willcox, C. & Suzuki, M. (2001). The Okinawa Way: How to improve your health and longevity dramatically. Penguin Books, London. England. ISBN: 0-718-14494-5

Valls-Pedret, C., Sala-Vila, A., Serra-Mir, M., Corella, D., de la Torre, R. … Rose, E. (2015). Mediterranean Diet and Age-Related Cognitive Decline: A Randomized Clinical Trial. JAMA Internal Medicine, 175(7). 1094-1103. DOI: 10.1001/jamainternmed.2015.1668