The relationship between nutrition and health is complex. Not only does poor nutrition contribute to poor health, but poor health may place an individual at nutritional risk. For example, poor health may result in higher medication and health related costs, leaving less money for food, and functional limitations may create barriers to accessing sufficient good quality food. This section will focus on the ways in which poor nutrition contributes to poor health, but keep in mind that the relationship between nutrition and health is complex.
One consequence of poor nutrition is unintended weight loss, which is an important predictor of the loss of bone, muscle and fat. Weight loss increases the risk of hip fracture, functional decline and early institutionalization. Low BMI is associated with increased mortality.
While in hospital, malnourished patients have more complications and longer hospital stays.
Deprivation of vitamins A, C, D and zinc, selenium and copper can interfere with immune function and increase susceptibility to infection. As a result, poorly nourished people are less resistant to infection and take longer to heal.
Chronic deprivation of adequate nutrients from fruits and vegetables increases the risk of cancer and cardiovascular disease.
The impacts of poor nutrition are not only physical. Dealing with food insecurity can be a source of significant worry and anxiety, and a lack of food can lead to feelings of anger and embarrassment.
Given the diverse effects of nutrition on health discussed above, it is not surprising that nutrition is important in the development and course of many illnesses and chronic conditions. The interaction between malnutrition and osteoporosis is discussed here as one example.
The underlying abnormality in osteoporosis is a decrease in bone mass and a microarchitectural deterioration of bone tissue. There is considerable evidence to suggest that nutrition is important in this disease process. Most patients with proximal femur fractures are undernourished and have decreased bone mineral densities. Undernutrition results in weight loss and decreased muscle mass, which may influence age-related changes in bone mineral density. In addition to weight loss, chronic protein malnutrition (as indicated by low blood albumin) may also be important as a predictor for bone loss.
3. Minister of Public Works and Government Services Canada. Nutrition and healthy aging: Workshop on health aging. 2002. Available at: http://www.phac-aspc.gc.ca/seniors-aines/pubs/workshop_healthyaging/nutrition/nutrition1_e.htm. Accessed: August 2005.