Health effects of seafood by-products
Products such as cod liver oil, fish proteins, and seaweed extracts are considered to have many health benefits, and have been marketed as such for years. But there has been little research on how these products are changed by storage, formulation, digestion and absorption by the body's cells. The EU-funded 'Bioactive compounds from seafood byproducts' (BIOSEAFOOD) project aimed to study the changes in such compounds in the period between harvesting and ingestion. Researchers focused on any losses in bioactivity, as well as the potential for positive or negative effects after digestion. Three groups of compounds were investigated: omega-3 oils in cod liver oil, fish hydrolysate (protein paste) and polyphenols in seaweed extract. All three groups were shown to be extremely stable in the production and storage phases. Cod liver oil, however, was changed during digestion. Hydrolysate and seaweed extracts showed good antioxidant properties, and all three caused changes in protein expression after digestion, thereby demonstrating bioactivity. Other significant findings were that seaweed extract stimulates the immune system, and that protein hydrolysates displayed anti-tumour effects. These results have shed light on how seafood products change within the digestive system. They confirm that the compounds have bioactivity, and also demonstrate new health benefits for the first time.
