Nutrition for the middle to later years of life

Good food choices and exercise between 50 and 70 years can help you defy ageing. For good health over 50, it is important to make sure that you eat nutrient-dense foods and that you remain physically active.

As people age, they tend to eat less, and therefore take in fewer calories and smaller amounts of important nutrients. In addition, it becomes more difficult for the body to digest and absorb certain vital nutrients. For example, in older people the amounts of calcium, vitamin B12, and folate in the diet often fall well below the recommended daily intakes.

Changing calorie needs with age

Your body changes as you get older and these changes affect your nutritional needs. There is a reduction in muscle, an increase in body fat, and your total body water decreases by up to 20 per cent. You need fewer calories than you did when you were younger since your basal metabolic rate (BMR; see Are you a healthy weight for your height?) decreases as muscle mass declines with age.

The good news is that moderate exercise helps preserve muscle mass and can thereby slow the rate at which this process occurs. Regular exercise has other benefits too - it keeps your bones strong, enhances mobility and flexibility, and increases your sense of well-being (see The importance of keeping fit).

The ageing digestive system

Digestion and absorption of food appear to be well preserved as people age. However, some of the digestive processes are affected. Saliva production decreases, which may affect how food is broken down in the stomach to prepare for digestion and absorption in the intestine.

The stomach reduces its secretion of acid and pepsin, which may lead to decreased absorption of vitamins B12, folate, and D and the mineral calcium. The smooth muscles in the intestine become less efficient, resulting in slower movement of food through the intestine and often constipation.

As you age, there is also a decline in the skin's production of vitamin D, which is necessary for the body to use calcium, making it more difficult for the body to meet its calcium needs. Calcium is especially important for women during and after the menopause. For all of these reasons, older adults should eat nutrient-dense foods and may also need to take supplements.

Health problems with age

Chronic disorders, such as arthritis, diabetes, cardiovascular disease, and osteoporosis, are more likely to develop after the age of 50.

The risk of other serious disorders such as cancer, heart attack, and stroke is also increased. You can reduce the risk or minimize the effects of many disorders by avoiding or eating certain foods (see Food as medicine).

In addition, if you have been prescribed any medications, they may affect your appetite or even prevent, or in some cases enhance, absorption of certain nutrients, vitamins, or minerals from the stomach or intestine (see The importance of keeping fit).

Drinking alcohol with age

Recent studies have suggested that moderate drinking (up to three to four units a day for men and up to two to three units daily for women) may have health benefits for older adults. These include improving mood, mixing socially, maintaining mental faculties, enhancing bone-mineral density, and improving cardiovascular health. For people with little interest in food, a small sherry before meals can stimulate appetite. However, many older people drink more than this, often due to depression or loneliness.

Too much alcohol can drain the body of water-soluble vitamins and decrease the absorption of other vitamins and minerals. It can also displace more nutritious foods. If you do consume alcohol, stay within the guidelines, remembering that home-poured measures are often larger than those on which the guidelines are based.

Lisa Hark, PhD RD & Dr Darwin Deen

Posted 14.02.2011

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