Tuberculosis and malnutrition are linked in a complex relationship. The
infection may cause undernutrition through increased metabolic demands
and decreased intake, and nutritional deficiencies may worsen the
disease, or delay recovery by depressing important immune functions. At
present, there are no evidence-based nutritional guidance for adults and
children being treated for tuberculosis.
To assess the effects of oral nutritional supplements (food,
protein/energy supplements or micronutrients) on tuberculosis treatment
outcomes and recovery in people on antituberculous drug therapy for
We searched the Cochrane Infectious Disease Group Specialized Register,
CENTRAL (The Cochrane Library), MEDLINE, EMBASE, LILACS, mRCT, and the
Indian Journal of Tuberculosis to July 2011, and checked the reference
lists of all included studies.
Randomized controlled trials comparing any oral nutritional supplement
given for at least four weeks with no nutritional intervention, placebo,
or dietary advice only for people being treated for active tuberculosis.
Data collection and analysis:
Two authors independently selected trials, extracted data, and assessed
the risk of bias. Results are presented as risk ratios (RR) for
dichotomous variables, and mean differences (MD) for continuous
variables, with 95% confidence intervals (CI). Where appropriate, data
from trials with similar interventions and outcomes have been pooled.
The quality of evidence was assessed using the GRADE methods.
Twenty-three trials, with 6842 participants, were included.
Five trials assessed the provision of free food, or high energy
supplements, although none were shown to provide a total daily
kilocalorie intake above the current daily recommended intake for the
The available trials were too small to reliably prove or exclude
clinically important benefits on mortality, cure, or treatment
completion. One small trial from India did find a statistically
significant benefit on treatment completion, and clearance of the
bacteria from the sputum, but these findings have not been confirmed in
larger trials elsewhere (VERY LOW quality evidence).
The provision of free food or high-energy nutritional products probably
does produce a modest increase in weight gain during treatment for
active tuberculosis (MODERATE quality evidence). Two small studies
provide some evidence that physical function and quality of life may
also be improved but the trials were too small to have much confidence
in the result (LOW quality evidence). These effects were not seen in the
one trial which included only human immunodeficiency virus
Five trials assessed multi-micronutrient supplementation in doses up to
ten times the dietary reference intake, and 12 trials assessed single or
dual micronutrient supplementation.
There is insufficient evidence to judge whether multi-micronutrients
have a beneficial effect on mortality in HIV- negative patients with
tuberculosis (VERY LOW quality evidence), but the available studies show
that multi-micronutrients probably have little or no effect on mortality
in HIV-positive patients with tuberculosis (MODERATE quality evidence).
No studies have assessed the effects of multi-micronutrients on cure, or
Multi-micronutrient supplements may have little or no effect on the
proportion of tuberculosis patients remaining sputum positive during the
first eight weeks (LOW quality evidence), and probably have no effect on
weight gain during treatment (MODERATE quality evidence). No studies
have assessed quality of life.
Plasma levels of vitamin A appear to increase following initiation of
tuberculosis treatment regardless of supplementation. In contrast,
plasma levels of zinc, vitamin D and E, and selenium may be improved by
supplementation during the early stages of tuberculosis treatment, but a
consistent benefit on tuberculosis treatment outcomes or nutritional
recovery has not been demonstrated.
There is insufficient research to know whether routinely providing free
food or energy supplements results in better tuberculosis treatment
outcomes, or improved quality of life. Further trials, particularly from
food insecure settings, should have adequate sample sizes to identify,
or exclude, clinically important benefits.
Although blood levels of some vitamins may be low in patients starting
treatment for active tuberculosis, there is currently no reliable
evidence that routinely supplementing at or above recommended daily
amounts has clinical benefits.
Plain language summary
Researchers in The Cochrane Collaboration conducted a review of the
effects of nutritional supplements for people being treated for
tuberculosis. After searching for relevant studies, they identified 23
relevant articles. Their findings are summarized below.
What is tuberculosis and how might nutritional supplements work?
Tuberculosis is a bacterial infection which most commonly affects the
lungs. Most people who get infected never develop symptoms as their
immune system manages to control the bacteria. Active tuberculosis
occurs when the infection is no longer contained by the immune system,
and typical symptoms are cough, chest pain, fever, night sweats, weight
loss, and sometimes coughing up blood. Treatment is with a combination
of antibiotic drugs, which must be taken for at least six months.
People with tuberculosis are often malnourished, and malnourished people
are at higher risk of developing tuberculosis as their immune system is
weakened. Nutritional supplements could help people recover from the
illness by strengthening their immune system, and by improving weight
gain, and muscle strength, allowing the patient to return to an active
Good nutrition requires a daily intake of macronutrients (carbohydrate,
protein, and fat), and micronutrients (essential vitamins and minerals).
What the research says: Effect of providing nutritional supplements to
people being treated for tuberculosis
We currently don't know if providing free food to tuberculosis
patients, as hot meals or ration parcels, reduces death or improves
cure. Providing free food probably does improve weight gain during
treatment, and may improve quality of life but further research is
We don't know if vitamins reduce death in HIV-negative people but they
probably don't work in HIV-positive people with tuberculosis. No
studies have assessed whether vitamins improve tuberculosis cure.
Vitamins probably don't improve weight gain, and no studies have
assessed their effect on quality of life.
Sinclair, D.; Abba, K.; Grobler, L.; Sudarsanam, T. D. Nutritional supplements for people being treated for active tuberculosis. Cochrane Database of Systematic Reviews (2011) Issue 11, Art. No. CD006086. [DOI: 10.1002/14651858.CD006086.pub3]
Nutritional supplements for people being treated for active tuberculosis.