Astaxanthin formula supports memory: study

A NuSkin study done on a mixed formula containing astaxanthin found a positive change in a measure of memory in a cohort of people suffering from self-reported cognitive difficulties. 

The new research was published in the journal Nutrients. It was the work of a team of researchers associated with a contract research organization, a university in Australia and Pharmanex Research, a division of NuSkin Enterprises. 

The researchers were investigating ways to help people suffering age-related cognitive decline, which they characterized as subjective memory complaints (SMCs).  They viewed SMCs as a marker of sorts for more profound issues down the road. 

“Older people with SMC are twice as likely to develop dementia compared to individuals without SMC. Approximately 2.3% and 6.6% of older people with SMC will progress to dementia and mild cognitive impairment (MCI) per year, respectively,” they wrote. 

By lessening the prevalence of SMCs, therefore, the researchers could assess the benefit of their formula in lessening the likelihood of developing those later, more profound issues, without the complications of dealing with an already diseased study population.  

Mixed suite of antioxidant ingredients 

For their intervention, the researchers used a formula that included 250 mg of grape juice extract, 12 mg of vitamin E and 9 mg of astaxanthin. All these ingredients have demonstrated antioxidant activity. High levels of oxidative stress have been associated with memory problems, the authors wrote. 

For the study population, researchers recruited 100 men and women who were about 59 years old who ranged from slender to mildly obese, and who were reporting mild memory difficulties. All of the subjects were living independently. The researchers excluded smokers and people who had a wide range of underlying conditions, including diagnosed cognitive disorders or dementia. The identically sized placebo and experimental groups both ended up with about four women to every man. 

For outcomes, the researchers measured the subjects’ performance on a range of standardized memory tests that measured changes in episodic memory, working memory and verbal learning and memory. They also measured as secondary outcomes a range of biomarkers associated with cognitive decline including plasma brain-derived neurotrophic factor (BDNF), malondialdehyde (MDA), Tumor Necrosis Factor-alpha (TNF-α), and Interleukin-6 (IL-6). In addition, other cognitive tests other objective measures of cognitive performance comprising accuracy of attention, speed of information processing, and visuospatial learning, all of which were included in the secondary analysis. 

The researchers asked the subjects to take the study formula, offered in 2 softgels, or an identical placebo once a day with meals for 12 weeks. The subjects were evaluated via the cognitive tests at baseline and again at 12 weeks, with blood being drawn at the same time. In between, the subjects self-reported the completion of questionnaires at 4 weeks and 8 weeks. 

Results present mixed bag 

The results presented a mixed bag, with only one of the three primary measures showing statistically significant improvement over placebo. 

“The results from this 12-week study provide some support for the cognitive-enhancing effects of a nutraceutical containing astaxanthin, vitamin E, and grape juice extract in adults with self-reported memory complaints. This was demonstrated by improvements in one primary outcome measure (episodic memory) but not working memory or verbal learning,” the authors wrote. 

For a possible mode of action for this effect, the researchers pointed to some of the measures of possible memory-related biomarkers. 

“Cognitive benefits may be achieved via the nutraceutical increasing BDNF (a neurotrophin) and reducing MDA (oxidative stress marker) concentrations,” they wrote. 

Importance of preserving episodic memory 

The authors noted that the change observed in episodic memory is promising, as changes in this form of memory are strongly correlated with the early stages of dementia. 

“Episodic memory is a cognitive process involving the retention, recall, and encoding of information about experiences and events concerning a specific time and place. During aging, episodic memory declines and has been suggested to be the most age-sensitive memory system. A worsening in episodic memory is one of the earliest and most common symptoms of mild cognitive impairment, and in people with Alzheimer’s disease, severe deficits are present in this cognitive process,” they wrote.