What is the difference in plant based versus fish based DHA?

Fish-based DHA utilizes the natural food chain for concentration. This is much more efficient and economical than the concentration processing applied to plant-based DHA, so we are able to produce a single piece softgel that is smaller than prenatals with plant-based DHA. While contaminants may be present in the fish that are sources of DHA, our enhanced purification process ensures that these are reduced to levels at or below detection limits.