Table 3.

Research gaps in the field of lipids and fatty acids in the preterm infant

Optimal targets	What are the postnatal target levels, circulating and within membranes/tissues, for specific long-chain polyunsaturated fatty acids and the balance among these fatty acids to support optimal health?
Context specificity	What are the competing risks across dosing strategies, timing of administration and end-organ responses? As potent regulators of inflammation, the ideal n-6:n-3 balance may depend on the physiological goals, such as supporting development and immune reactivity during periods of vulnerability to acute events, such as sepsis versus assisting in the termination of the inflammatory response during periods of chronic, unmitigated inflammation.
Formulation	What are the oil sources and fatty acid composition of a parenteral lipid emulsion that achieve the desirable effect in total lipid and fatty acid delivery? What is the impact of the other factors in lipid emulsions that have their own distinct metabolic responses such as phytosterol content, vitamin E and phospholipid species and concentration?
Systems biology integration	What is the impact of lipid and fatty acid delivery beyond changes in fatty acid levels? How does it impact lipogenesis in other lipid classes, protein use, glucose production and cellular energy? How does it regulate the production of proinflammatory and anti-inflammatory mediators, host immune cell responsiveness, adipokines and other endocrine axes?