Abstract
Maintaining health during ageing has become a major public health initiative as the proportion of the world’s population aged over 65 years has increased markedly. Macroalgae have been incorporated in the diet for generations, especially in East Asia. Nutritional changes to include macroalgae may provide possibilities for interventions to prevent or reverse the hallmarks of ageing. Their potential to assist in healthy ageing relies on their complex composition including carbohydrates, proteins, minerals, vitamins, fibre and secondary metabolites such as phlorotannins, oxylipins and terpenoids. However, most studies are in animal models with few studies examining the responses in humans to long-term intake. Likely mechanisms of action include reversal of chronic inflammation and gut dysbiosis as part of the changes during ageing. There is now a wide range of foods that incorporate macroalgae, including bread, noodles, yogurt, gluten-free products, and meat and seafood products. Key future priorities with macroalgae include increasing the range of species available for human consumption, defining the health benefits in humans and domestic animals, improving accessibility and decreasing the risk of toxicity from pollutants. Further, health may be improved by indirect effects including wastewater remediation, production of bioenergy and biofertilisers, and decreasing methane production by ruminants. These uses also increase knowledge of macroalgal biology, especially the use ofmolecular engineering techniques to increase sustainable macroalgal biomass production.