Twelve weeks of supplementation in middle-aged people with subjective memory complaints was also associated with significant increases in plasma brain-derived neurotrophic factor (BDNF)—an important neurotrophic factor participating in memory and learning, compared to placebo.
Additionally, the vitamin E, astaxanthin and grape juice extract supplement led to significant decreases in plasma malondialdehyde (MDA), a reactive carbonyl compound and a marker of oxidative stress.
“[G]iven the promising improvements in episodic memory identified in this study, it is postulated that the nutraceutical may have protective effects in this brain region,” wrote researchers from Clinical Research Australia, Murdoch University (Australia) and Utah-based Pharmanex Research. “However, this requires confirmation in future trials.”
Study details
The researchers recruited 100 people between the ages of 40 and 70 to participate in their double-blind, randomized, placebo-controlled study. The participants were equally divided into two groups: One group received a daily supplement containing 12 mg of vitamin E (d-alpha tocopherol), 9 mg of astaxanthin and 250 mg of grape juice extract, and the other group received a placebo.
The results showed that the antioxidant-rich supplement led to larger improvements in episodic memory, compared to placebo, but no improvements were recorded for working memory or verbal learning.
Additionally, based on data from the Everyday Memory Questionnaire, a secondary outcome measure of cognitive performance, participants in the active supplement group reported a 42% improvement in memory over the course of the study, compared to an 18% increase in the placebo group.
For BDNF, the researchers reported that levels increased by 46% over 12 weeks in the active supplement group, compared to 24% in the placebo group.
“The increases in plasma BDNF from the nutraceutical intervention also suggest its neuroprotective effects may be via its ability to increase this important neurotrophin,” the researchers wrote in Nutrients. “BDNF is essential for neuronal survival and growth, and the signaling cascades initiated by BDNF and its receptors are critical regulators of synaptic plasticity.”
For MDA, the data indicated a non-significant 12.5% decrease in the active supplement group, compared to a “near-significant” 26.5% increase for placebo.
The researchers said the “promising findings from this study” should be validated and expanded in future studies conducted with larger sample groups and using “more comprehensive cognitive assessments and assessing additional mechanisms of action.”
The study was funded by NSE Products Inc. (Nu Skin).
Source: Nutrients
2024, 16(11), 1770; doi: 10.3390/nu16111770
“An Examination into the Effects of a Nutraceutical Supplement on Cognition, Stress, Eye Health, and Skin Satisfaction in Adults with Self-Reported Cognitive Complaints: A Randomized, Double-Blind, Placebo-Controlled Trial”
Authors: A.L. Lopresti et al.