Energy And Nutrient Requirements
Energy requirements continue to fall with advancing age. This is due to a decrease in lean body tissue (muscle), leading to a fall in basic metabolic rate (BMR). Older people also tend to be less active. It is important that older people continue to enjoy their food and that they keep active (e.g. walking, gardening, dancing, climbing stairs) in order to maintain a good appetite, maintain mobility and prevent obesity.
For older people the ability to digest, absorb, metabolise and excrete nutrients, changes with age (e.g. vitamin B12 absorption is decreased because the intrinsic factor needed for its absorption is thought to decrease with age). There are, however, specific recommendations for vitamin D. Vitamin D is necessary for calcium absorption and is mainly obtained from the action of sunlight on the skin. People who are housebound or live in institutions may be at risk of deficiency. It is recommended that everyone over the age of 65 takes a supplement of vitamin D, and dietary sources such as oily fish and margarine (which is fortified with vitamin D - link to margarines and spreads) should be eaten regularly.
It is also important that older people eat enough foods to cover their energy requirements and that the food they eat are nutrient dense, i.e. a small portion of the food contains a lot of nutrients. Many older people have to modify their diets to help control illnesses such as diabetes and heart disease, but if an older person is in good health, it is recommended that they follow the general dietary guidelines for the population.