Personalising nutrition for older adults

Helen R Griffiths of the University of Surrey explains why a personalised strategy for nutrition is a sustainable way to improve health in the elderly population. She describes the EU INCluSilver project, which aims to develop and validate innovative ideas in the field of personalised nutrition for the silver economy.

The UK population is getting older, with 18% of people aged 65 and over and 2.4% aged 85 and over (Table 1). This should be a cause for great celebration but the years of life in good health are not increasing at the same rate as the length of life. The older a person is, the more likely they are to suffer with chronic health conditions, such as dementia, diabetes and arthritis.

In 2017, the UK life expectancy was reported as 79.5 years for males and 83.1 years for females but healthy life expectancy is now 63.4 for males and 64.1 for females with an average of 19 years in ill health for men (red) and women (blue; see Figure 1).

Table 1 Age distribution of the UK population, 1976 to 2016 Source: Office for National Statistics

Figure 1 From health-profile-forengland/ chapter-1-life-expectancyand-healthy-life-expectancy. Source: Healthy life expectancies and life expectancies from ONS reports, with prevalence of good health derived from their surveys: General Household Survey/General Lifestyle Survey for years 2000 to 2002 up to 2008 to 2010, and the Annual Population Survey for years 2009 to 2011 up to 2012 to 2014.

The importance of diet for health outcomes with ageing

It is increasingly recognised that the rate of biological ageing is malleable and that interventions can be implemented by individuals that will reduce the rate of health decline. The most obvious of these are an Increase in exercise and improvement of diet; one of the few interventions to increase longevity is caloric restriction and evidence for this extends across species and into higher mammals^[1]. However, while lowering calorie intake has been shown to improve lifespan, this needs to be balanced against daily requirements for essential nutrients. The diet of an older person, who is not underweight, should be nutrient-rich but without excess calories.

There is substantial evidence in support of specific foods, dietary patterns and nutrients in the prevention of chronic diseases and mortality^[2]and in improving the quality of life with ageing^[3].

Public health advice about nutrition is general in nature in order to address the need to improve the health of the wider population. Several nutritional recommendations are well established and promoted through the Food Standards Agency. These include advice on consuming oily fish each week and eating at least five portions of fruit and vegetables daily. Taking this a step further, the concept of personalised nutrition capitalises on individual differences in response to various nutrients depending on their age, lifestyle activities, genotype and epigenome.

In moving towards a personalised nutrition strategy for older adults, dietary recommendations will need to be fine-tuned to an individual’s health, activity, preferences and motivations.

There is substantial evidence in support of specific foods, dietary patterns and nutrients in the prevention of chronic diseases and mortality and in improving the quality of life with ageing.

Personalising nutrition for older adults – energy needs

It is difficult to generalise about the energy requirements of older adults because of the variation in health and mobility in people over 65 years of age. Nevertheless, energy requirements are likely to be the same as for younger adults during good general health and when mobility is maintained. However, in the oldest adults and for those who have much less mobility, it is highly likely that their physical activity levels will be lower; consequently their energy requirement will also be lower. The Scientific Advisory Committee on nutrition in the UK has estimated energy requirements based on average age, height and mobility (Figure 2)^[4]. The change in energy requirement is most striking, with reduced energy needs, in people over the age of 65 years. This is most likely because the amount of muscle and types of muscle fibres change from the mid-50s and muscle has a high energy requirement; slower metabolism is related to loss of muscle.

In the UK, total daily energy intake is estimated as 9.8MJ/d for the average man aged 65-74 dropping to 9.6MJ/d for a man of more than 75 years. For women, total daily energy intake is estimated as 9.86MJ/d dropping to 9.6MJ/d respectively.

If energy intake is maintained with reducing energy expenditure, body fat accumulates around the organs of the body, with much less fat within the subcutaneous fat deposits. Deposition of visceral body fat increases the risk to diseases like type 2 diabetes and increases in prevalence with older adults. Energy intake is an important area of personalisation – too high an intake will increase the risk of metabolic disease but on the other hand, if intake is too low in older adults, malnutrition can result and predispose an older person to the development of frailty syndrome.

Figure 2 Gender and age effects on estimated average energy requirements in the UK at current mean height and BMI (22.5Kg/m2; 2)

Personalising nutrition for older adults – protein

The dietary protein intake that is required by people of different ages to meet their nitrogen balance has been discussed extensively in the published literature. The safe limit for protein intake takes into account the possibility that renal function may be compromised by high protein intake in older adults. The World Health Organisation recommends 0.75g protein per Kg body weight per day for older adults, the same as for adults under 65 years of age^[5]. An increase in protein intake, particularly of proteins rich in branched chain amino acids, can improve muscle damage in younger people but does not appear to protect against loss of skeletal muscle mass and strength (sarcopenia) in older adults. Instead, a recent pilot study has highlighted that increasing intake of the essential amino acid leucine should be investigated in greater depth^[6]. Such a personalised approach may be useful in people with sarcopenia.

Personalising nutrition for older adults – vitamins

The reference intakes for vitamins do not increase with age although for some, e.g. for niacin, there is a minor reduction in requirements between young and older adults over the age of 50. Table 2 describes vitamin requirements for UK older adult populations. The data was collated by the British Nutrition Foundation^[7]in 2016.

Vitamin D is considered a non-essential vitamin because it can be synthesised on exposure to sunlight. However, a comprehensive review of vitamin D and health^[8]concludes with a recommended intake of 10 μg daily for men and women in the UK over 50 years of age. Currently, in the UK the average intake from the diet alone is 3.3µg i.e. 1/3 of the requirement. For those taking supplements, the mean daily intakes were 5.1µg vitamin D for men and 5.2µg for women. This is approximately 50% of the recommended intake for vitamin D. Older people on lower incomes and people who are living in care homes also have lower intakes; in care homes, mean daily vitamin D intake from all sources was for men 3.9µg and for women 3.4µg.

Geography and ethnicity also play an important part in the nutritional intake patterns of otherwise healthy older adults and highlight a specific calcium requirement for health. For example, Pakistani men and women living in the UK typically consume less calcium^[9].

The capacity to make vitamin D from sunlight is also affected by skin pigmentation. However, the prevalence of vitamin D deficiency in older adults living in Europe according to ethnicity is unclear, although cases of rickets were recorded in much greater frequency in children of South Asian, Middle Eastern or sub-Saharan African background. Increasing vitamin D intake is being recognised as an important public health goal. The aforementioned evidence points to ethnicity as a factor to consider in personalised nutrition.

Table 2 British Nutrition Foundation Population Reference Intakes (PRIs) for micronutrients in older adults

​In the near future, a risk calculation based on genotype for such long-term conditions is likely to emerge that would encourage a personalised nutrition approach to reduce disease risk.

Personalising nutrition in the future

People with long term conditions, such as high blood pressure, high cholesterol and type 2 diabetes, which increase in prevalence in older adults, have dietary requirements for foods that are lower in fat, salt and refined sugars. There are certain genotypes that increase risk for these metabolic diseases. In the near future, a risk calculation based on genotype for such long-term conditions is likely to emerge that would encourage a personalised nutrition approach to reduce disease risk. One of the first European studies that used genomic information to advise individuals on their personal risk profile and to develop an appropriate nutritional programme has now concluded. The study identified that personalised nutrition advice resulted in participants selecting a much healthier diet, irrespective of whether the genomic information was used. This suggests that personalised nutrition could be a sustainable way to improve health^[10].

Other factors to consider in personalising nutrition in older adults

An important consideration in foods for adults with poor oral health and dental problems is to minimise meals that require chewing while maintaining fibrous and protein content. Protein enriched foods have been successfully used in the hospital setting but cost, taste and scepticism from consumers have not helped with wider uptake.

Nutritional health may be affected by drug treatments that affect appetite, absorption and metabolism. Conversely, some foods also affect drug metabolism, most notably grapefruit that impairs the activity of cytochrome p450 metabolising enzymes and so increases blood concentrations of drugs. These factors are addressed in drug safety notes that accompany medicines.

The aforementioned data assumes that absorption of nutrients is also unaffected although if an individual has physiological changes with ageing, e.g. in gastric acid secretion, the absorption of B vitamins may be impaired hence intake requirements may be higher. In this case, the state of an individual’s health will impact on their personal dietary requirements. The clinical practitioner will assess whether this is the case on a personalised basis if an individual presents with symptoms of B vitamin deficiency. In this case, the motivation to increase a specific nutrient would be health-related via a pharmacist rather than lifestyle choice dependent.

Personalised strategies to improve nutrition in older adults

Overall, the success of adopting personalised nutrition in an older adult population will be the result of integrating different approaches to improve dietary intake of nutrients. These should take into account any personal monitoring devices that an individual has for existing health conditions e.g. for blood sugar and blood pressure, wearables that monitor activity and mobile apps that offer coaching. Together these could help to integrate lifestyle and medical variables to improve the perceived importance of diet and compliance with healthy nutrition.

Research has shown that nutritional strategies would be more likely to be adopted if they include a range of technologies that enable users to monitor their status. This could include wearable devices that monitor lifestyle and energy needs, self-diagnostic devices that report on nutritional requirements and app technology that includes motivational tools and encourages people to stick with the nutritional programme. Each of these technological possibilities for the silver economy is founded on the principle of understanding the requirements and benefits of particular nutrients for older adults. Food choices change with age and are influenced by many factors including changing taste, budget as well as lifestyle. Superimposed on food choice factors are nutritional requirements; these also change with age.

In moving towards a personalised nutrition strategy, dietary recommendations should be fine-tuned to an individual’s health, activity, preferences and motivations.

Food choices change with age and are influenced by many factors including changing taste, budget as well as lifestyle.

Introducing InCluSilver

In March 2017, the InCluSilver Innovation Support project was established after a successful funding award from the European Union^[11]. Bringing together nine partners across Europe over three years, it aims to help create products, services and systems that improve the health and quality of life for older adults through innovation in personalised nutrition. INCluSilver aims to fund excellent innovations from SMEs through the award of vouchers. The two final call deadlines are 15th September 2018 and 15th February 2019. Competitive bids are reviewed by a panel of experts with funding awarded to the most innovative. SMEs are encouraged to work with users of the innovative products, services and health care systems both nationally and internationally.

Innovation requirements for engaging with INCluSilver

In order to help innovators to create products, services and systems that improve the quality of life for older people through innovation in personalised nutrition, we have developed the following project guide. Successful InCluSilver projects will address the following challenges and gaps:

• Use knowledge of silver consumer behaviour to support the uptake of personalised nutrition by older adults

• Develop services and systems that define individual nutritional needs based on lifestyle, genotype, activity and health status

• Design and implement systems that enable monitoring of nutritional health status in older adults

• Develop new foods that meet the nutritional, taste and mastication requirements for healthy older adults in health and those with chronic conditions associated with older age

• Develop meal packaging and preparation approaches that can be physically managed by older adults

• The adaptation and development of personal monitoring devices for reporting on the effect of meals on health indices

• Design and implementation of mobile apps that offer coaching on diet based on user-friendly but highly detailed data.

Helen R Griffiths

Professor of Biomedical Sciences, Departments of Nutritional and Biochemical Sciences, Faculty of Health & Medical Sciences, University of Surrey

Emailh.r.griffiths@surrey.ac.uk

Web inclusilver.eu surrey.ac.uk

Please visit the INCluSilver website or contact the author directly to find out more.

References

1. Anton S, Leeuwenburgh C. Fasting or caloric restriction for healthy aging. Experimental gerontology. 2013;48:1003-5.

2. Kiefte-de Jong, J.C.; Mathers, J.C.; Franco, O.H. Nutrition and healthy ageing: The key ingredients. Proc. Nutr. Soc. 2014, 73, 249–259.

3. Jankovic, N.; Geelen, A.; Streppel, M.T.; de Groot, L.C.; Orfanos, P.; van den Hooven, E.H.; Pikhart, H.; Boffetta, P.; Trichopoulou, A.; Bobak, M.; et al. Adherence to a healthy diet according to the World Health Organization guidelines and all-cause mortality in elderly adults from Europe and the United States. Am. J. Epidemiol. 2014, 180, 978–988.

4. Scientific Advisory Committee on Nutrition Dietary Reference Values for Energy 2011

5. WHO/FAO. Report of a Joint Expert Consultation. Protein requirements of adults, including older people, and women during pregnancy and lactation. Geneva (Switzerland): WHO Press; 2007 (UNU report 05123054).

6. Ispoglou, T., H. White, T. Preston, S. McElhone, J. McKenna and K. Hind (2015). "Double-blind, placebo-controlled pilot trial of L-Leucine-enriched amino-acid mixtures on body composition and physical performance in men and women aged 65–75 years." European Journal of Clinical Nutrition 70: 182.

7. https://www.nutrition.org.uk/attachments/article/234/Nutrition%20Requirements_Revised%20Oct%202016.pdf

8. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/537616/SACN_Vitamin_D_and_Health_report.pdf

9. http://onlinelibrary.wiley.com/doi/10.1046/j.1365-277X.2003.00461.x/epdf

10. https://clinicaltrials.gov/show/NCT01530139

11. https://www.inclusilver.eu/about-inclusilver/