Nutritious supplemental foods for pregnant women from food-insecure settings
This is a summary of the following paper: Mihaela A, Ciulei AM, Nandita P et al (2023) Nutritious supplemental foods for pregnant women from food insecure settings: Types, nutritional composition, and relationships to health outcomes. Current Developments in Nutrition, 7, 6. https://www.sciencedirect.com/science/article/pii/S2475299123247678
Pregnancy is characterised by an increased demand for energy and nutrient intake, with poor nutrition during this period being a contributor to adverse maternal and infant health outcomes. There is growing evidence that the provision of nutritious supplemental foods to undernourished pregnant women can improve birth outcomes. However, comparing and synthesising the evidence base is challenging due to differences in intervention design and products and the use of ambiguous terminology. This study aimed to define balanced energy-protein (BEP) supplements and lipid-based nutrient supplements (LNS) and to review the evidence supporting each by a narrative review of systematic reviews and meta-analyses (SRMAs).
BEP supplements differ from LNS because they provide 25% of energy from protein, while LNS provides less than 50% of energy from fat (including essential fatty acids). There are three formations of LNS – small-,1 medium-,2 and large-3 quantity LNS. The energy provided by medium- and large-quantity LNS overlaps with some BEP supplements, but the proportion of fat and protein differentiates the two.
This study identified five SRMAs (20 trials) that evaluated the effect of BEP compared with no BEP/control. BEP supplements ranged in calories (118 to 1,017 kilocalories), protein (3 to 50 grams), fat (6 to 57 grams), and micronutrient content. Overall, BEP improved birth weight and reduced the risk of stillbirth and small for gestational age. A total of three SRMAs (five trials) evaluated the effect of LNS compared with iron folic acid (IFA) or multiple micronutrients (MMNs). The LNS interventions comprised small- and large-quantity LNS that ranged in calories (118 to 746 kilocalories), protein (3 to 21 grams), fat (10 to 53 grams), and micronutrient content. When compared with IFA, LNS increased pregnancy duration, birth weight, and birth length and reduced the risk of small for gestational age and infant stunting. However, no beneficial effect of LNS was identified when compared with MMN.
Despite heterogeneity in the nutritional composition of BEP supplements, which complicates interpretation of results, the evidence suggests that these products may improve birth outcomes in nutritionally at-risk populations. Further research is needed to clarify the most appropriate BEP supplement composition required and which pregnant women would benefit most from interventions. The evidence for LNS compared with IFA is promising but limited. There is a need for more homogenous evidence to clarify whether there is a benefit in providing LNS over MMNs.
1 Small-quantity LNS provides 20 grams of food per day, including 3 grams (9%) of protein and 10 grams (73%) of fat and is meant to complement food in the diet.
2 Medium-quantity LNS, also known as ready-to-use supplementary food, has traditionally been used to treat moderate wasting and provides between 45 and 90 grams per day of supplementary food, of which 6 grams (10%) is protein and 16 grams (58%) is fat.
3 Large-quantity LNS, which is also referred to as ready-to-use therapeutic food, has been used to treat severe wasting in children and provides between 180 and 280 grams per day of supplementary food, of which 15 grams (16%) is protein and 28 grams (67%) is fat.