Apple concentrate consists primarily of vitamin C. Vitamin C is known to be a powerful antioxidant (85). Studies have suggested that it can increase endothelial nitric oxide by protecting it from oxidation and increase synthesis, another function that Vitamin C has suggested includes reducing blood pressure (86), however the only proven function of vitamin C is the prevention of scurvy (87).
85 – Kalt, W., Forney, C. F., Martin, A., & Prior, R. L. (1999). Antioxidant capacity, vitamin C, phenolics, and anthocyanins after fresh storage of small fruits.Journal of Agricultural and Food Chemistry, 47(11), 4638-4644.
86 – Huang, A., Vita, J. A., Venema, R. C., & Keaney, J. F. (2000). Ascorbic acid enhances endothelial nitric-oxide synthase activity by increasing intracellular tetrahydrobiopterin. Journal of biological chemistry, 275(23), 17399-17406.
87 – Padayatty, S. J., Katz, A., Wang, Y., Eck, P., Kwon, O., Lee, J. H., … & Levine, M. (2003). Vitamin C as an antioxidant: evaluation of its role in disease prevention. Journal of the American College of Nutrition, 22(1), 18-35.