February 9, 2019
This blog is by Dr Sze-Yen Tan, Senior Lecturer in Nutrition and Accredited Practicing Dietitian, Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University. His research focuses on the effects of nuts and taste on body weight and metabolic health.
Older adults are at risk for malnutrition
According to the United Nations, 1 in 8 adults in the world was aged over 60 years in 2015. This number is projected to reach 1 in 5 adults by 2050. Older adults have increased requirements for some nutrients but a large proportion of them do not meet these increased requirements. Suboptimal intake may lead to malnutrition if not corrected. A recent review reported that 26.5% of community-dwelling and 49.0% of older adults living in a rehabilitation and sub-acute care setting are at risk for malnutrition. Preventative measures are therefore needed urgently.
The drivers of energy and nutrient intake
Energy and nutrient intake can be enhanced by increasing the nutrient density and portion size of foods, and the frequency of eating. Increasing food portion sizes at main meals may not be viable for older adults who experience loss of appetite. However, food fortification and supplementing meals with nutritious snacks have been shown to improve overall oral nutritional intake of older adults.
Nuts are nutritious
Nuts are naturally high in energy (29 kJ/gram) and they are packed with nutrients such as unsaturated fats, protein, vitamin E, calcium, copper, iron, magnesium and zinc. These nutrients are not only essential in meeting the increased requirements in older adults, but are also beneficial in the prevention and management of health conditions such as heart disease, diabetes and mental health, which are commonly seen in this population.
Despite the seemingly-promising characteristics of nuts, there are some potential barriers too. From research, we know that the nutrients in nuts are not readily available as they are encapsulated within cell walls. Studies have also shown that nut consumption promotes fullness, an effect that may work against efforts to increase older adults’ food intake. Finally, nuts are hard and present as a major challenge to individuals with dentition issues.
What can we do?
While evidence does not appear to favour the use of nuts in improving the nutritional intake of older adults, some modifications may overcome the challenges above. We propose 3 simple strategies that make nuts suitable for older adults:
- Transform the forms of nuts. Processing nuts into a butter form maximises the release of nutrients from nuts for absorption. This will overcome the dentition issues that may be faced by some older adults.
- Introduce variety. Various types and forms (if no dentition concerns) of nuts could be used in older adults. Nut variety may overcome the feeling of fullness stimulated by repeated consumption of a similar food (also known as sensory-specific-satiety). This is especially important when older adults are already experiencing poor appetite. Furthermore, various nuts have different nutrient profiles. Mixing the types of nuts will increase the range of nutrients consumed by older adults.
- Eat nuts between main meals. In addition to the strategies above, nuts should be consumed as snacks to avoid interfering with food intake at main meals. Increasing eating frequency has also been shown to increase total energy and nutrient intake. We propose the use of ‘nut milkshake’ (blending nut butter with dairy- or non-dairy milk) to further increase the nutrient-density. Unlike main meals, beverages can be consumed throughout the day and they affect appetite minimally.
Footnote: A conceptual framework of using nuts to mitigate malnutrition in older adults was presented at the 42nd Annual Scientific Meeting of the Nutrition Society of Australia in Canberra. This framework will guide future research investigating the effectiveness of nuts supplementation on the nutritional status and wellbeing of older adults.
The full version of this review is available as: Tan, S.-Y.; Tey, S.L.; Brown, R. Can Nuts Mitigate Malnutrition in Older Adults? A Conceptual Framework. Nutrients 2018, 10, 1448.
To read the full manuscript click here.
Image credits to Vegan Liftz