Factors Affecting Nutrition: Religious Practices, Lifestyle, Economics, Medication and Therapy, and Health
Religious practice also affects diet. Some Roman Catholics avoid meat on certain days, and some Protestant faith prohibit meat, tea, coffee, or alcohol. Both Orthodox Judaism and Islam prohibit pork. Orthodox Jews observe kosher customs, eating certain foods only if they are inspected by a rabbi and prepared according to dietary laws. The nurse must plan care with consideration of such religious dietary practices.
Certain lifestyles are linked to food-related behaviors. People who are always in a hurry probably buy convenience grocery items or eat restaurant meals. People who spend many hours at home may take time to prepare more meals "from scratch". Individual differences also influence lifestyle patterns (e.g., cooking skills, concern about health). Some people work at different times, such as evening or night shifts. They might need to adapt their eating habits to this and also make changes in their medication schedules if they are related to food intake.
Muscular activity affects metabolic rate more than any other factor; the more strenuous the activity, the greater the stimulation of the metabolism. Mental activity, which requires only about 4 Kcal per hour, provides very little metabolic stimulation.
What, how much, and how often a person eats are frequently affected by socioeconomic status. For example, people with limited income, including some elders, may not be able to afford meat and fresh vegetables. In contrast, people with higher incomes may purchase more proteins and fats and fewer complex carbohydrates. Not all persons have the financial resources for extensive food preparation and storage facilities. The nurse should not assume that clients have their own stove, refrigerator, or freezer. In some low-income areas, food costs at small local grocery stores can be significantly higher than at large chain stores farther away.
Medication and Therapy
The effects of drugs on nutrition vary considerably. They may alter appetite, disturb taste perception, or interfere with nutrient-absorption or excretion. Nurses need to be aware of the nutritional effects of specific drugs when evaluating a client for nutritional problems. The nursing history interview should include questions about the medications the client is taking. Conversely, nutrients can affect drug utilization. Some nutrients can decrease drug absorption; others enhance absorption. For example, the calcium in milk hinders absorption of the antibiotic tetracycline but enhances the absorption of the antibiotic erythromycin. Elders are particularly risk for drug-food interactions due to the number of medications they may take, age-related physiologic changes affecting medication actions (e.g., decrease in lean-to-fat ratio, decrease in renal or hepatic functions) and disease-restricted diets.
Therapies (e.g., chemotherapy and radiation) prescribed for certain diseases may also adversely affect eating patterns and nutrition. Normal cells of the bone marrow and the gastrointestinal mucosa are naturally very active and particularly susceptible to antineoplastic agents. Oral ulcers, intestinal bleeding, or diarrhea resulting from the toxicity of antineoplastic agents used in chemotherapy can seriously diminish a person's nutritional status.
The effects of radiotherapy depend on the area that is treated. For example, radiotherapy of the head and neck may cause decreased salivation, taste distortions, and swallowing difficulties, radiotherapy of the abdomen and pelvis may cause malabsorption, nausea, vomiting and diarrhea. Many clients feel profound fatigue and anorexia (loss of appetite).
An individual's health status greatly affects eating habits and nutritional status. The lack of teeth, ill-fitting dentures, or a sore mouth makes chewing food difficult. Difficulty swallowing (dysphagia) due to painfully inflamed throat or a stricture of the esophagus can prevent a person from obtaining adequate nourishment. Disease processes and surgery of the gastrointestinal tract can affect digestion, absorption, metabolism, and excretion of essential nutrients. Gastrointestinal and other diseases also create nausea, vomiting, and diarrhea, all of which can adversely affect a person's appetite an nutritional status. Gallstones, which can block the flow of bile, are a common cause of impaired lipid digestion. Metabolic processes can be impaired by disease of the liver. Diseases of the pancreas can affect glucose metabolism or fat digestion.
Between 30 million and 50 million Americans have lactose intolerance, a shortage of the enzyme lactase which is needed to break down the sugar in milk. Certain populations are more widely affected: As many as 80% of African Americans, 80%-100% of American Indians, and 90%-100% of Asian Americans are lactose intolerant.