Algae are composed of both microalgae and macroalgae and are being explored as a sustainable food source and bioresource with great potential in health, nutraceutical, and pharmaceutical areas. The functional food components of algae contain bioactive compounds with several secondary metabolites. Algae can have polysaccharides, polyphenols, pigments, alkaloids, terpenoids, and sterols, which can potentially assist with several disorders. Bioactivities can possess antioxidants, anti-inflammatory, antimicrobial, antiviral, anticancer, immunomodulatory, and neuroprotective activity, which can be exploited. These bioactivities can be directly explored as natural metabolites for drug discovery and will have advantages over synthetic drugs, which will only target one mechanism. Most algal metabolites/plant-based compounds actively work against several targets and can have fewer side effects, which allows for useful therapeutic alternatives that are safe and natural. As technology advances in biological systems, omics tools, and green extraction advances, bioactive compounds have been and can now be identified, isolated, and produced at bulk levels in both the laboratory and industrial settings. Algae can also be utilized in developing algae-based formulations and in creating nutraceuticals, which can act as an adjunctive therapeutic panacea to ease chronic diseases such as diabetes, cardiovascular, cancer, and neurodegenerative diseases. This chapter will discuss contemporary discoveries and developments in the molecular pathways influenced by algal-derived metabolites, especially on their potential role to reduce oxidative stress and thus inflammation, apoptosis, and immune response. In conclusion, we will address issues related to standardization, scaling, and regulatory acceptance. In addition, we will stress the significance that integrated research can make to apply research from the laboratory to clinically approved therapies. Algae are a potential area of development for disease management and promoting human health because of their ability to connect natural bioresources to the needs of the modern pharmaceutical market.