This Cochrane review aimed to summarise the evidence from systematic reviews of supplementary feeding for food insecure, vulnerable and malnourished populations, including children under five years of age, school-aged children, pregnant and lactating women, people with HIV or tuberculosis (or both), and older populations.
This overview included eight systematic reviews (with last search dates between May 2006 and February 2016). Seven were Cochrane Reviews evaluating interventions in pregnant women; children (aged from birth to five years) from LMIC; disadvantaged infants and young children (aged three months to five years); children with moderate acute malnutrition (MAM); disadvantaged school children; adults and children who were HIV positive or with active tuberculosis (with or without HIV). One was a non-Cochrane systematic review in older people with Alzheimer's disease. These reviews included 95 trials relevant to this overview, with the majority (74%) of participants from LMIC.
The review found that for pregnancy, energy and protein supplements that were balanced (i.e. providing adequate amounts of energy and nutrients, in this case protein) may decrease the rate of stillbirth (death or loss of a baby before or during delivery), improve infant birth weight and reduce the risk of infants born small-for-gestational age (infants that are smaller than expected). High-protein supplements (containing protein in higher amounts) were associated with risk and harm (increased risk of small-for-gestational age babies).
We found that the effects of supplementary feeding on growth in children were varied. In children under five years of age from low- and middle-income countries, supplementary feeding had a small impact on child growth. We observed some benefits in terms of weight and height gains, especially in younger children (those younger than two years of age) and in those who were poorer or less well-nourished (or both). Some benefit could be seen in children with moderate acute malnutrition in terms of weight gain, other growth factors and recovery rate. School meals seemed to lead to a number of small benefits in school children (including improvements in weight, height, intelligence tests, and maths and spelling performance).
Supplementary feeding in adults who were HIV positive increased the daily intake of energy and protein and led to an early improvement in weight gain or body mass index (measure of whether someone is overweight or underweight), or both, but did not seem to lead to long-term benefits (although few studies reported long-term effects). In adults with tuberculosis (serious infectious lung disease), we observed small benefits in terms of weight gain during active tuberculosis.
Considering the current evidence base included, supplementary food effects are modest at best, with inconsistent and limited mortality evidence. The trials reflected in the reviews mostly reported on short-term outcomes and across the whole of the supplementation trial literature it appears important outcomes, such as quality of life and cost of programmes, are not systematically reported or summarised.