Evidence Level
Hemp seed oil is a plant-based supplement characterized by its unique fatty acid profile, including a favorable 3:1 omega-6 to omega-3 ratio and gamma-linolenic acid (GLA) content. A study by Callaway et al. (2005) demonstrated that dietary hemp seed oil alleviates symptoms of atopic dermatitis, such as dryness and itchiness, compared to olive oil control. The mechanism involves GLA conversion to dihomo-γ-linolenic acid (DGLA), which competes with arachidonic acid in cyclooxygenase/loxygenase pathways.
Schwab et al. (2006) highlighted the benefits of hemp seed oil supplementation, showing favorable changes in plasma fatty acid profiles and cholesterol ratios. Deferne & Pate (1996) established the comprehensive fatty acid composition of hemp seed oil, underscoring its optimal omega-6:omega-3 ratio and GLA content.
Recent studies have expanded on hemp seed oil's applications. Farì et al. (2023) found that a supplement combining hemp seed oil with terpenes significantly improved pain and joint function in knee osteoarthritis patients compared to hemp seed oil alone. Additionally, Rezapour-Firouzi et al. (2013) demonstrated that a hot-nature diet combined with hemp seed and evening primrose oils improved clinical scores and immunological markers in multiple sclerosis patients.
While the evidence base for hemp seed oil is smaller than for other oils like fish or flaxseed, its unique combination of balanced omega ratios, GLA, and bioactive compounds positions it as a distinctive plant oil warranting further investigation across various health conditions.