Consuming grass finished lamb improves blood plasma ω-3 fatty acid response among healthy consumers

BACKGROUND AND PURPOSE: Dietary intakes of omega-3 polyunsaturated fatty acids (ω-3 PUFA) are below what is recommended. Meat from grass finished ruminants contains higher levels of ω-3 PUFAs, particularly, alpha-linolenic acid (C18:3 ω-3). The impact of consuming grass finished lamb meat rich in ω-3 PUFA on blood fatty acid (FA) response in humans is not well established. This study investigated the impact of consuming grass finished lamb on total blood plasma and blood plasma phospholipids (PL) FA and on cardiovascular risk factors, including heart rate, blood pressure (BP), HDL, LDL, total cholesterol, and TAG, in humans. METHODS: A single blinded, randomised controlled trial was conducted. Two portions of lamb chops and one portion of lamb mince from lambs finished on a grass or concentrate diet were consumed per week by 34 healthy participants for four consecutive weeks. Blood samples were taken at baseline and post-intervention. Approximately ~ 328 mg/100 g of total ω-3 PUFA was present in grass finished lamb portions per week. RESULTS: Greater levels of ω-3 PUFA, namely C18:3 ω-3, eicosapentaenoic acid (C20:5 ω-3) and docosapentaenoic acid (C22:5 ω-3), were detected in total blood plasma from participants who consumed grass finished lamb (P < 0.05), while consuming concentrate finished lamb higher levels of linoleic acid (C18:2 ω-6) in plasma PL (P < 0.01). There were no differences of consuming grass or concentrate finished lamb on cardiovascular risk factors. CONCLUSION: This study demonstrates that ω-3 PUFA from lamb meat finished on grass is reflected in blood ω-3 PUFA response. Grass finished lamb is a useful matrix for increasing intake of ω-3 PUFA into the human body alongside little required change to customary dietary habits. CLINICALTRIALS: gov ID: NCT06607354. Retrospectively registered 24/09/2024.