Lucy Jones, MRES BSC Hons RD MBDA
Every year, countries all over the world are seeing their populations living longer, with a greater proportion of them living as older adults. In fact, average life expectancy has doubled over the past 200 years, increasing two years every decade1. Unfortunately, while many people are living longer, many of those years are spent managing chronic illness and disability so we now need a strong focus on ways to increase ‘healthy’ life expectancy2. Nutrition and diet are well evidenced in their ability to not only alter life expectancy but also quality of life; with good diets helping people to stay well and active, for longer2.
Aging brings changes in body composition with loss of strength and muscle mass, loss of bone mass, impairments in our digestive functions, as well as changes to dental health. Risk of chronic diseases like heart disease, stroke, dementia and osteoporosis all increase. Changes in skin mean that less vitamin D is produced, leaving people vulnerable to bone loss and placed at further risk due to vitamin D deficiency2.
Diet plays a critical role in health at every life stage and as we age, what we eat not only affects the length of life, but also the risk of developing chronic diseases like dementia or heart disease in addition to mood, energy levels and body composition. A good diet helps the body recover quickly from injury or illness and helps to preserve muscles and bones. Hydration is crucial too; healthy hydration levels reduce the risk of cancer, kidney stones and heart disease while dehydration doubles the risk of death from a stroke3.
Immune systems can become impaired as we age and poor diets can make this worse. Low protein, energy deficient diets and micronutrient deficiencies (for example zinc, copper, iron, selenium, vitamins C, A, E, D, B6, B12) impair immune function and may increase the risk and severity of infections4. However, evidence shows that long chain omega-3 fatty acid supplementation and antioxidants may help to reduce acute inflammation4.
One in four people over the age of 85 are visually impaired and 50 percent of visual impairments in older people are due to treatable conditions such as cataracts, refractive error and diabetic retinopathy2. Nutrients from the AREDS2 study (lutein, zeaxanthin, vitamin C, vitamin E, zinc, copper, and omega 3s eicosapentaenoic acid [EPA], and docosahexaenoic acid [DHA]) set forth by the National Institutes of Health remain the most proven nutritional therapy for reducing the rate of advanced age-related macular degeneration (AMD)5, and may also help reduce the risk of cataracts5. This makes dietary advice to eat a colourful diet full of fruits and vegetables in addition to one portion of oily fish per week essential for long-term eye health.
While there are clear benefits to helping older adults improve their nutrient intakes, there is a nutritional conflict as we age whereby our requirement for nutrients increase because of poorer absorption within our digestive systems but our calorie needs decrease because of changing metabolisms and lower activity levels. This means we need to eat less energy but more nutrients, which is a difficult balance to achieve.
In addition to helping people alter their food choices to maximize healthy fats, protein, fiber, vitamins and minerals by enhancing diet quality, we should also look at supplements. Supplements can play a positive role in helping those with poor appetites or restricted diets due to poor oral health, chronic disease or difficulty prepping or cooking food to meet their nutritional needs and maintain their health.