Are you Maintaining a Healthy Omega-3 Status?
Have you ever taken a bath where the tub slowly drained? When it does, you have to keep dribbling in water. Otherwise, you are in a puddle not a bath. Of course, too much water too fast isn’t good because the tub soon overflows. Nutrition is similar to taking a bath. We constantly need to add water (nutrients). We don’t want to bathe in a puddle (or be deficient). We don’t want to overfill (excess). The goal is to keep optimal levels of nutrients in our bodies.
The Estimated Average Requirement (EAR) is a calculation based on a sampling of people (bath tubs). The EAR is an estimate of the average flow rate needed to keep the average tub at a constant level of fullness. The Recommended Dietary Allowance (RDA) is the flow rate estimated to keep 97.5% of baths at a constant level of fullness. This may work for public health but it can make for an extremely uncomfortable bath. Why? Because bathing is an individual experience which requires one to monitor water depth and adjust flow rate based on leakage.
In nutrition, we need more focus on monitoring bath water depth (status) and less on measuring faucet flow rate (intake). This can be done more easily in hospital settings. When children with severe acute malnutrition (SAM) are hospitalized, blood samples can be taken to monitor nutrition status.
In a prospective study in Uganda, Babierekere-Irisio and colleagures measured whole blood fatty acids in children. As children with SAM were administered ready-to-use therapeutic foods (RUTF) providing 3-10% of total energy as n-6 fatty acids in hospital, their blood n-6 :n-3 PUFA ratio increased from 7.9 to ~12. The n-6:n-3 ratio was higher than that in healthy children (8.9). Omega-3 long chain PUFA concentrations decreased while being fed RUT, especially in children from families who regularly consumed fish at home. The authors concluded that RUTF formulations should include more n-3 long chain fatty acids.
Measuring blood fatty acid concentrations gives a clearer picture of nutrition status (depth of water in the tub). Balancing n-6 and n-3 fatty acids in RUTFs is important. The n-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), can be obtained from fatty seafood, fortified foods, and dietary supplements.
The recommendation is to maintain EPA+DHA concentrations in red blood cell membranes above 8%.
Babirekere-Iriso E, Mortensen CG, Mupere E, Rytter MJH, Namusoke H, Michaelsen KF, Briend A, Stark KD, Friis H, Lauritzen L. Changes in whole-blood PUFA and their predictors during recovery from severe acute malnutrition. 2016 Br J Nutr doi: 10.1017/S0007114516000817
World Health Organization (2007) Joint Statement on the Community-Based Management of Severe Acute Malnutrition. Geneva: WHO
Brenna JT, Akomo P, Bahwere P, Berkley JA, Calder PC, Jones KD, Liu L, Manary M, Trehan I, Briend A. Balancing omega-6 and omega-3 fatty acids in ready-to-use therapeutic foods (RUTF). 2015 BMC Med doi: 10.1186/s12916-015-0352-1
Harris WS, von Shcacky C. The omega-3 index: a new risk factor for death from coronary heart disease? 2004 Prev Med doi: 10.1016/j.ypmed.2004.02.030
Gebauer SK, Psota TL, Harris WS, Kris-Etherton PM. n-3 fatty acid dietary recommendations and food sources to achieve essentiality and cardiovascular benefits. 2006 Am J Clin Nutr 83:S1526-1535