Consumption of lettuce with seaweed extract biostimulant application improved iron homeostasis in a randomized interventional trial of healthy individuals

Minerals have key roles in the body's metabolism and homeostasis. Biostimulants application to vegetables, such as seaweed extracts derived from Ecklonia maxima (SwE), is a useful agronomic approach to improve crop yield and quality by a naturally functionalizing process. We hypothesized that SwE biostimulants would impact the minerals profile of the lettuce and the consumption of lettuce with SwE application would affect blood minerals concentration in the health population. This in turn would impact metabolic pathways essential for human homeostasis. A group 48 healthy adults, of both sexes, was allocated in a double-blinded manner into groups that consumed 100 g a day of control lettuce, lettuce with SwE application or an iron tablet (30 mg) for four weeks. Blood samples were collected at baseline (T0) and at the end of the trial (T2) and compared for differences in serum mineral concentrations, iron, lipid and glucose homeostasis. In lettuce, SwE biostimulant enhanced iron concentration by about 63%. The consumption of lettuce with SwE application increased serum iron by about 38%, transferrin saturation by about 47%, and reduced total cholesterol by about 19% and Low-density lipoprotein by about 22%. Supplementation of iron in tablets has similar effects to lettuce with SwE application but with side effects (diarrhea or constipation). The study offers an innovative perspective by assessing lettuce with SwE application as a natural alternative to iron supplements that are commonly associated with gastrointestinal side effects. The results are of interest in the context of dietary iron deficiency especially among populations that avoid meat-based diets. This research could have broad implications for enhancing the nutritional value of plant-based foods to support dietary health by promoting intersection of sustainable agriculture and human nutrition.Clinical trial registration number: NCT06656871.