Nutrition and dementia

18 Nov 2019

by Kirsty Robinson, Older People’s Dietitian At Whipps Cross University Hospital, London; she is currently studying NIHR MRes part time and sits on the BDA Older People’s Specialist Group committee.

Dementia has reached epidemic proportions as the worldwide population lives longer. It is more prevalent among older adults, however it is not a normal part of ageing. In 2016 dementia accounted for 12% of all registered deaths in England and Wales, making it the leading cause of death using WHO disease groupings, ahead of ischemic heart diseases (11%) (1 - see references below). There are approximately 700,000 informal carers caring for their loved ones with dementia; this fi gure is expected to rise to 1.7 million by 2050 (2).

Current UK Government advice to reduce the risk of developing dementia (3):

  • eat a healthy diet (as depicted in the Eatwell Guide)
  • maintain a healthy weight
  • exercise regularly
  • don’t drink too much alcohol
  • stop smoking (if you smoke)
  • make sure to keep your blood pressure at a healthy level

Q. What are the risk factors for developing dementia?

Some dementia risk factors are non-modifi able for example age and genetics, however many risk factors may be modifi able through lifestyle alterations and/or pharmacological treatment. Possible nutrition related risk factors include: nutrition prior to birth (intrauterine life); low birth weight and stunting in early life are independently associated with lower cognitive ability in adulthood; longer leg length and larger skull circumference (indicating favourable early development) are associated with lower dementia prevalence; obesity in midlife may be a risk factor for developing dementia in late life but evidence is confl icting. Potential mechanisms include: insulin resistance, infl ammation and cardiovascular disease (4).

There is currently no evidence that specifi c individual nutrients such B vitamins, antioxidants or omega-3 Polyunsaturated Fatty Acids (PUFA) can reduce our risk of developing dementia (4,5).

Q. Does the Mediterranean diet reduce risk of dementia?

The most convincing evidence is that a Mediterranean style diet may be benefi cial in addition to adapting various aspects of a healthy lifestyle; including taking regular exercise, participating in lifelong learning, not smoking, and maintaining normal blood pressure and cholesterol levels (5,6). These studies appear to show associations between diet and cognition, however one of the main limitations of this type of study is that they cannot show cause and effect. They are long-term observational studies. There may be other unmeasured factors that account for the results, such as genetics, other medical conditions, exercise, or medication. They also rely on self-reported estimates of dietary intake, so there is a possibility for recall and reporting bias.

There is no single Mediterranean diet, however these diets tend to include higher intakes of vegetables, fruit, legumes, cereals, fish and monounsaturated fatty acids; lower intakes of saturated fat, dairy products and meat; and a moderate alcohol intake. Mediterranean type diets are said to broadly align with current UK healthy eating recommendations as depicted in the Eatwell Guide (3).

Q. What impact can dementia have on an individual’s nutritional status?

Malnutrition risk increases as dementia progresses (7,8,9). People who have dementia have been found to account for ten times more admissions to hospitals when compared to age-matched controls (10). This may be due to an increased risk of dehydration, dysphagia, falls, chest infections, and malnutrition which can be related to dementia progression. 

Q. What impact can nutrition and dementia have on informal carers?

Eating and drinking difficulties can be a major source of stress for people living with dementia and their carers. Addressing these challenges was identified as one of their top-ten research priorities by people with dementia and their formal/informal carers (11). Papachristou, Hickey, and Iliffe (2015) completed a qualitative study where they interviewed 20 informal care givers. This study found four main themes which were important to informal care givers. These include:

  • direct food-related information (written material, and training)
  • direct food-related informal support services (lunch clubs)
  • indirect food-related formal support services (respite care and help in the home)
  • no services required (because of confidence in managing food-related processes and no change in dementia progression and food responsibility)

Further research is required to establish the best ways to support people who have dementia, their informal/ formal care givers with regards to managing nutritional changes experienced over time. Dietitians play a vital role in education for patients and formal/informal care givers.

Q. Nutritional interventions – what evidence is there?

Several recent reviews have found no definitive evidence of either effectiveness or lack of effectiveness for any specific nutrient or non-nutrient intervention for combating under-nutrition in those who have dementia (11,12,13,14). An individualised patient-centred approach addressing people’s different needs appears to be the most beneficial (11). The reviews commented that studies that had been published tended to be small and short term. Despite the lack of high-quality evidence, the studies acknowledged that people living with dementia and their carers still need advice on nutritional interventions that might be helpful.

Murphy et al (2017) recently published “a model for understanding the provision of good nutritional care for people living with dementia in nursing homes”. The seven domain areas identified as important were: 

  • person-centred nutritional care (the overarching theme)
  • availability of food and drink
  • tools, resources and environment
  • relationship to others when eating and drinking
  • participation in activities
  • consistency of care
  • provision of information

Q. What practical advice can dietitians give if someone is losing weight without trying to or has a reduced appetite to maintain their weight and strength?

New NICE (NG97) guidance has been published in June 2018:

“1.10.6 Encourage and support people living with dementia to eat and drink, taking into account their nutritional needs.”

“1.10.7 Consider involving a speech and language therapist if there are concerns about a person’s safety when eating and drinking.”

  • Address underlying barriers to eating and drinking with the person and MDT; dysphagia, constipation, poor dentition, oral thrush, depression, infection, dexterity, social context and environment for example.
  • Food First 1,2,3 approach; increase protein, calories and nutrient density. This can include one pint of fortified milk or homemade fortified milkshake, two nourishing snacks and three fortified meals.
  • Consider trialling; finger foods, assistance with eating and drinking (promote as much independence as possible), adapted cutlery and crockery (ensure food contrasts with the plate), foods previously liked in the past, sweet foods.
  • Consider recommending a vitamin D supplement 10ug if the person isn’t already taking one.
  • Encourage the person to be active and to do activities they enjoy.
  • If food first and nourishing drink approaches do not meet the goal of care consider if a trial of prescribable nutritional supplements is indicated for a specific goal and timespan.

Q. Should people who have dementia be given clinically assisted nutrition and hydration (CANH)?

CANH is usually administration of food and fluids via a nasogastric tube or via a gastrostomy. Multiple systematic reviews of mainly observational studies have concluded that CANH in advanced dementia does not provide benefit in terms of: (4, 15, 16, 17, 18)

  • prolonging survival
  • improving quality of life
  • leading to better nourishment
  • decreasing the risk of pressure sores
  • decreasing risk of aspiration pneumonia

NICE (NG97) guidance was published in June 2018: “1.10.8 Do not routinely use enteral feeding in people living with severe dementia, unless indicated for a potentially reversible comorbidity.”

CANH is regarded in law as a medical treatment. The GMC guidance on treatment and care when reaching end of life recognises that some people see nutrition and hydration, whether oral or artificial, as basic human nurture which should almost always be provided (19).

Q. What about nutrition in later stages of dementia?

People who have advanced cancer often report anorexia, nausea and cachexia in the final stages of disease (20). People who have advanced dementia may not be able to verbally communicate that they are not hungry. However they may show signs they do not wish or are not able to eat by keeping their mouth closed, spitting food out, coughing, choking or pocketing food. This can be a difficult time for carers and relatives too.

It is thought that people with later satages of dementia are likely to experience a similar decline in appetite as people who have other palliative conditions report. During the late stage of dementia the emphasis may need to change from active treatment to palliative care with the emphasis placed on provision of food and eating for comfort and pleasure, and not necessarily nutritional adequacy.


1. ONS (Offi ce for National Statistics) (2017) Deaths registered in England and Wales (Series DR): 2016, UK: Offi ce for National Statistics.

2. Alzheimer’s Association. (2016). 2016 Alzheimer’s Disease Facts and Figures. Retrieved from custom/2016-facts-and-fi gures. pdfGoogle Scholar

3. NHS (2016) Dementia Guide: Can dementia be prevented? [online]. Available at: http:// dementia-guide/pages/dementiaprevention.aspx [Accessed 25/08/2016].

4. Prince et al (2014) Alzheimer’s International “Nutrition and Dementia - A review of available research” 2014; Page 72.

5. Scientific Advisory Committee on Nutrition (2018) SACN Statement on Diet, Cognitive impairment and Dementias publications/sacn-statement-ondiet-cognitive-impairment-anddementia

6. Hayden et al. (2017) The Mind Diet and Incident Dementia, Findings from the Women’s Health Initiative Memory Study. (Funder(s): National Institutes on Aging)

7. Haveman-Nies A, de Groot LC, Van Staveren WA. (1997) Fluid intake of elderly Europeans. The Journal of Nutrition, Health and Aging. 1997;1:151–5. 12.

8. Martin MA, Barrera Ortega S, Dominguez Rodriguez L, Couceiro Muino C, de Mateo SB, del Rio MP R. (2012) Presence of malnutrition and risk of malnutrition in institutionalized elderly with dementia according to the type and deterioration stage. Nutr Hosp. 2012;27:434–40.

9. Jesus P et al. (2012) Nutritional assessment and follow-up of residents with and without dementia in nursing homes in the Limousin region of France: a health network initiative. J Nutr Health Aging. 2012; 16:504–8

10. Natalwala A, Potluri R, Uppal H et al. (2008) Reasons for hospital admissions in dementia patients in Birmingham, UK, during 2002–2007. Dement Geriatr Cogn Disord. 2008;26:499–505

11. Abdelhamid, A., Bunn, D., Copley, M., Cowap, V., Dickinson, A., Gray, L., Hooper, L. (2016). Effectiveness of interventions to directly support food and drink intake in people with dementia: Systematic review and meta analysis. BMC Geriatrics, 16(1), 1. https://doi. org/10.1186/s12877-016-0196-3

12. Bunn DK, Abdelhamid A, Copley M, et al. (2016) Effectiveness of interventions to indirectly support food and drink intake in people with dementia: Eating and Drinking Well IN dementiA (EDWINA) systematic review. BMC Geriatrics. 2016;16:89. doi:10.1186/s12877- 016-0256-8.

13. Mole L, Kent B, Abbott R, Wood C, Hickson M. The nutritional care of people living with dementia at home: A scoping review. Health Soc Care Community. 2018;26:e485–e496.

14. Herke M, Fink A, Langer G, Wustmann T, Watzke S, Hanff A, Burckhardt M. Environmental and behavioural modifications for improving food and fluid intake in people with dementia. Cochrane Database of Systematic Reviews 2018, Issue 7. Art. No.: CD011542. DOI: 10.1002/14651858.CD011542. pub2

15. Sampson, E.L.; Candy, B.; Jones, L.(2009) Enteral tube feeding for older people with advanced dementia. Cochrane Database Syst. Rev.2009, 15, 396–404.

16. Volkert D et al. (2015) ESPEN Guidelines on Nutrition and Dementia. Clinical Nutrition 34 1052e1073

17. Brooke J et al. (2015) Enteral Nutrition in Dementia: A Systematic Review: Nutrients, 2015, 7; 2456-2468

18. Dementia: assessment, management and support for people living with dementia and their carers NICE guideline [NG97] Published date: June 2018

19. General Medical Council (2010) Treatment and care towards end of life; good practice in decision making. End of life care and clinically assisted nutrition.

20. Hui D, Dev R, Bruera E. (2015) The Last Days of Life: Symptom Burden and Impact on Nutrition and Hydration in Cancer Patients. Current opinion in supportive and palliative care. 2015;9(4):346-354. doi:10.1097/ SPC.0000000000000171.

21. Murphy JL, Holmes J, Brooks C (2017) Nutrition and dementia care: developing an evidencebased model for nutritional care in nursing homes. BMC Geriatrics 17:55, p.4

22. Papachristou, Hickey, and Iliffe (2015) Dementia informal caregiver obtaining and engaging in food-related information and support services. Dementia . Vol 16, Issue 1, pp. 108 - 118

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