7-MEGA^TM is a food product made from purified Alaska pollack fish oil containing palmitoleic acid (16:1), commonly referred to as omega-7. We sought to quantitatively evaluate whether this substance inhibits skin aging. A total of 101 middle-aged females were randomly allocated to the intervention (N = 50) or placebo group (N = 51). Each participant was advised to take either 500 mg of 7-MEGA^TM or a placebo twice daily for 12 weeks. The primary outcomes were the degree of improvement in wrinkles and the degree of moisture filling after consumption for 12 weeks compared to baseline. The secondary outcomes were improvement in skin wrinkles; moisture changes at 4 and 8 weeks from baseline; changes in transdermal water loss, skin elasticity, the melanin index, the erythema index, and the Global Photo Damage Score. We found a significant improvement in skin wrinkles and elasticity at 12 weeks in the 7-MEGA^TM-consuming group compared to that in the placebo group; skin moisture, elasticity, and the melanin index were also improved. No supplement-related adverse reactions were observed and 7-MEGA^TM was identified as safe. 7-MEGA^TM was effective for human skin function in terms of wrinkles, moisture, elasticity, and melanin production and may be useful as a skin nutritional supplement.