STRASBOURG, FRANCE ? SEPTEMBER 2007:  Elderly residents at the Pavilion Schutzenberger in Strasbourg, France. The ageing of societies of developed countries, particularly Europe, mainly results from falling fertility rates and increasing life expectancy. European countries and Japan will face the highest ageing trends in the developed world between now and 2050. In that time, the 60+ age group in Europe will rise to account for 37% of the population, and even higher in Japan, compared to North America where it will account for 27% of the population. In Europe, the 80+ age group will account for 10% of the population. As older people are more prone to disease and illness, there will be an increased burden on society to provide for and support the senior citizens. The population of disabled elderly in the richest countries is also growing rapidly. The number of very old people will suffer functional disability due to arthritis, stroke, diabetes, coronary artery disease, cancer, or cognitive impairment is expected to increase at least 300 percent by 2050 in the post-industrial Western nations. Adequate nutrition and a well balanced diet is of vital importance in old age to prevent and control the common hazards of aging: under nutrition, obesity, diabetes, cardiovascular diseases and osteoporosis. The ageing of Western societies over coming decades will require comprehensive reforms of pensions, social benefits and systems of healthcare and long-term care.  (Photo by Patrick Landmann/Getty Images)