Effective treatment of tuberculosis (TB) is available in South Africa but cure rates remain unacceptably low. Nutrition and dietary habits play an important role in the prevention and treatment of TB.
Nutritional factors that increase TB risk
Nutritional deficiencies are generally associated with an increased risk for contracting TB and has an effect on the severity of the disease.
The poorer the diet, the more likely it is that a person will develop complications associated with this disease. In addition, the nutritional status of people (whether they get all the nutrients their bodies need) and utilisation of nutrients (how their bodies use these nutrients) are also adversely affected after they have been infected.
What's more is that malnutrition could diminish the effectiveness of the drug regimens, which must be taken by TB patients. A weakened immune system - caused by malnutrition - can be quickly and easily corrected by just giving your body the nutrients it needs. Thus, nutritional intervention in combination with appropriate pharmaceutical therapy, as is the case in HIV-infected patients, could improve the outcome in malnourished TB patients.
Nutritional response to infection
Once infected with TB, the body starts using more and more energy trying to fight the infection, and in addition, the infection often causes a loss of appetite in the patient, resulting in the patient losing weight.
An increase in protein breakdown leads to muscle wasting in these patients. The breakdown of protein and other reserves due to fever may also worsen under nutrition and further impair resistance against the infection.
The increased energy expenditure and tissue breakdown associated with infection are thought to increase the requirements of micronutrients such as vitamin A, E, B6, C, D and folate. It is also known that a decrease in trace elements such as iron, zinc and selenium occur during the infection.
Nutritional treatment of TB
The risk and morbidity of infections are influenced by the nutritional status of the individual. Likewise, the nutritional status and the intake and utilisation of foodstuffs are profoundly altered during the body's response to infection. Factors that affect food intake, such as food availability, appetite, eating patterns, medication side effects, traditional food taboos, lifestyles (smoking, alcohol, physical activity, caffeine intake, use of social drugs), psychological factors (stress and depression), stigma, and economic factors are also very important to consider.
The South African National Department of Health produced the “South African National Guidelines on Nutrition for People Living with HIV, Aids, TB and other Chronic Debilitating Conditions” in 2007. Here are their recommendations for people living with TB:
Nutritional needs in tuberculosis
- Energy: Energy needs of TB patients are increased because of the disease itself. In the case of Aids, energy requirements increase by 20 to 30% to maintain body weight.
- Protein: Protein is important to prevent the wasting of body stores (for example muscle tissues).
- Micronutrients: A good multivitamin and mineral supplement, providing 50 to 150% of the recommended daily allowance, is advisable since it will be most unlikely that a person with TB will be able to meet the increased requirements for vitamins and minerals with diet alone (due to a poor appetite).
Nutritional needs of children with TB
The rapid growth periods of infancy and childhood can only be maintained if a child's nutrient intake is optimal. Because of the link between malnutrition and TB, all children presenting with malnutrition or with failure to gain enough weight must be evaluated for possible TB.
Children with TB need a lot of energy and nutrients since the child has increased requirements as a result of both growth and TB. The fact that children have limited stomach capacity and appetites makes it particularly challenging to meet the nutrient requirements. It is therefore necessary to modify and plan the diet carefully to ensure adequate intake of food.
Here are some recommendations on how to monitor weight gain and detect malnutrition in children:
- There is no documented evidence that any specific food on its own can alter the course of the disease or can for that matter be effective in the treatment of malnutrition. TB and HIV/Aids patients are encouraged to eat healthily.
- Pulmonary disease often adversely affects nutritional intake due to poor appetite, making patients at risk for malnutrition. Six smaller meals per day are indicated instead of three.
- The meals should be appetising in appearance and taste and provide enough energy and protein.
- Commercially-available high energy and protein drinks (balanced in terms of micro- and macronutrients) may be used effectively to meet the increased requirements.
- Household ingredients such as sugar, vegetable oil, peanut butter, eggs and non-fat dry milk powder can be used in porridge, soups, gravies, casseroles or milk based-drinks to increase the protein and energy content without adding to the bulk of the meal.
- At least 500ml to 750ml of milk or yoghurt should be consumed daily to ensure adequate intakes of vitamin D and calcium.
- At least five to six portions of fruit and vegetables should be eaten per day. Pure fruit juice can be used to decrease the bulk of the diet. Approximately half a glass of fruit juice is equal to one portion of fruit.
- The best dietary sources of vitamin B6 (pyridoxine) are yeast, wheat germ, pork, liver, whole grain cereals, legumes, potatoes, bananas, and oatmeal.
- Alcohol should be avoided.
- Adequate fluid intake is important due to increased losses (at least 10 to 12 glasses per day).
- A good multivitamin and mineral supplement.
- Safe food handling and personal hygiene is very important. The following precautions for preventing or minimising food or waterborne diseases are recommended in “The South African National Guidelines on Nutrition for People Living with HIV, Aids, TB and other Chronic Debilitating Conditions”.
Read more about food safety principles for people with a compromised immune system.
For further personalised and more detailed information, please contact NICUS or a dietician registered with the Health Professions Council of South Africa
NICUS (Nutrition Information Centre University of Stellenbosch
Department of Human Nutrition
P.O. Box 19063, Tygerberg, 7505, Tel: 021-933 1408, Fax: 021-933 1405, email: firstname.lastname@example.org, www.sun.ac.za/nicus/