Experts discuss food's role in the health of the elderly. Sylvia Thompson reports
Adapting diets to reduce the incidence of Alzheimer's disease and osteoporosis and to improve the general health of older people was the theme of a recent two-day conference on Research on Nutrition and Ageing at the European Commission, Brussels, Belgium.
Researchers from Britain, Denmark, France, Germany, Greece, Ireland and Italy gave reports of ongoing studies investigating how certain fatty acids in the diet could have a preventative role in the treatment of Alzheimer's disease.
The importance of vitamin D in the prevention of osteoporosis and whether vitamin D food fortification/supple-mentation programmes should be developed for older people also gained attention.
The potential health benefits of functional foods (such as probiotics) developed specifically for older people were also discussed.
Older people currently make up 20 per cent of the population in Europe and this is expected to rise to 25 per cent by 2020. Those living to 80 years and over are expected to increase in number the most. It is estimated that the number of people over 80 years of age in Europe will grow from 21.4 million in 2000 to 35 million in 2025.
These demographic changes were the impetus for the Brussels conference as well as belief that the nutritional needs of older people have received little attention to date compared with other population groups such as children.
Dr Tobias Hartmann of the Centre for Molecular Biology, Heidelberg, Germany is the co-ordinator and principal investigator of the multi-centre study into the role of fatty acids in the prevention of Alzheimer's disease.
Researchers have found that certain dietary fats increase the production of toxins which are believed to cause Alzheimer's disease.
Some studies have also shown that when cholesterol levels are lowered, the levels of these molecular toxins also decrease.
Drug companies are repeating such studies to see if by taking statins (cholesterol- lowering drugs), patients can also reduce their risk of developing Alzheimer's disease.
Meanwhile, experimental results from the Centre for Molecular Biology in Heidelberg and its research partners indicate that a diet can be designed to delay the development of Alzheimer's disease.
Current research focuses on how long a diet needs to be changed for significant effects and what specific foods would have to be included in such a diet.
Generally speaking, the belief is that the diet would have to be low in cholesterol, low in saturated fatty acids and high in polyunsaturated fatty acids.
The importance of vitamin D (gained from exposure to sun and dietary sources) for bone health is well established as vitamin D is a crucial component in the body's absorption of calcium into the bones.
Therefore, vitamin D deficiency is a risk factor in hip fracture, the number of which, due to osteoporosis, is expected to increase from 414,000 to 972,000 in Europe by 2050.
Vitamin D deficiency is known to be very common in older people.
Rikke Andersen from the Department of Nutrition, Danish Institute of Food and Veterinary Research, Söborg, Denmark discussed whether the fortification of food (particularly breads) with vitamin D would increase the amount of this vitamin in our bodies and whether such a fortification programme would be accepted by European consumers.
The conclusions to date of the survey, which was carried out in five European countries including Ireland, are that vitamin D fortification and/or supplementation are effective and reasonably cheap ways of slowing down the onset of degenerative diseases such as osteoporosis. But, the levels to achieve optimal effects without toxicity have yet to be worked out.
The third project which was discussed was a study that found that bacteria present in the gut of older people is significantly different from that in younger age groups.
Some researchers suggest that the decrease of bifidobacteria in particular could be linked to the development of age-related diseases associated with the colon.
This has led to research into whether new types of functional food such as probiotics should be developed specifically for the older population.
At the Brussels conference, Dr Joe Doré, Unit of Ecology and Physiology of the Digestive System, from the National Research Institute of Agronomics, discussed the possibilities of the food industry developing a functional food which would enhance the composition of healthy bacteria in the gut of older people.
All the above research projects are funded by the EU research framework programmes. For more information on each project, see also: www.lipidiet.org; www.optiford.org; www.crownalife.be