This chapter explores the critical role of omega-3 polyunsaturated fatty acids (PUFA), focusing on α-linolenic acid from linseed oil. It begins by explaining the types of omega-3 fatty acids (FA), including α-linolenic acid (ALA), stearidonic acid (SDA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), detailing their distinct health benefits. The following sections provide an in-depth analysis of the digestion, absorption, and metabolism of omega-3 FA, elucidating how they are processed within the body. Special emphasis is placed on the extensive health benefits of linseed oil across various body systems. In terms of cardiovascular health, omega-3 FAs improve serum lipid profiles and regulate signal transduction pathways. For brain health, their potential in reducing the risk of stroke and Alzheimer’s disease is highlighted. The chapter also discusses omega-3 FA’s anti-inflammatory properties and their role in immune system modulation, as well as oxidative stress reduction. Furthermore, there are discussions about hepatoprotective effects against nonalcoholic fatty liver disease with antidiabetic benefits through serum triglyceride regulation. This chapter also addresses metabolic syndrome improvement along with contributions to skin, hair, and digestive health. This holistic review highlights the significant benefits of including linseed oil in dietary regimens to improve overall health.