In the news: Omega-3 May Improve Cognition in Elderly; Supplemental Carotenoids in Pregnancy

Can Omega-3s Benefit Cognition in Elderly?

According to the results of a meta-analysis(1) conducted by university researchers in China, supplemental omega-3s improve cognition in those with mild cognitive impairment (MCI) – often an early sign of Alzheimer’s disease.

Although there are previous meta-analyses looking at the relationship between the omega-3s and cognition, most of them did not focus on MCI. The current meta-analysis included 12 randomized trials with 1,224 participants 60 years or older with MCI.

The studies were conducted in China, the UK, Spain, Italy, Malaysia, and Iran, and all the studies had an intervention with DHA alone or combined with EPA, and placebo.

In trials examining DHA alone, the dose ranged from 800 to 2,000 mg daily, while the dose of total EPA plus DHA in trials testing both fatty acids varied from 300-1,800 mg daily. The interventions lasted from 2 to 24 months. The trials assessed global cognitive function, memory, and symptoms of depression as outcome measures.

The researchers report that supplementation with omega-3 fatty acids versus placebo benefited global cognition, a measure of overall cognitive function [Standardized Mean Difference= 0.51, p= 0.01]. No significant differences were observed between the intervention group and placebo on language fluency, executive functions, and depression.

The authors note the omega-3 fatty acid supple-mentation may also reduce the level of blood amyloid-beta and related biomarkers as well as some inflammatory factors (e.g., Il-6 and -10). However only two of the twelve studies measured these biomarkers, so no conclusions can be drawn.

Supplemental Carotenoids in Pregnancy

Evidence suggests that carotenoids play a functional and protective role in infant visual and cognitive development. In the third trimester of pregnancy, mothers transfer their store of nutrients via the placenta to support the baby’s central nervous system development, potentially putting mothers at risk of systemic and ocular carotenoid depletion.

Including the carotenoids lutein (L) and zeaxanthin (Z) in prenatal micronutrient supplement formulations has been promoted to enhance infant visual and neural development and to maintain maternal health. However, these claims are not yet supported by a compelling prospective trial.

Researchers at the Moran Eye Institute, University of Utah set out to investigate the effects of supplemental L and Z on maternal and infant ocular health. They hypothesized that supplementation with L and Z would improve carotenoid status in mother and infant, and that infants with the highest systemic and ocular carotenoid status would have a more mature foveal structure at birth. The first report from this trial(2) is now published. It suggests that prenatal L and Z may have health benefits for women and their babies.

Forty-seven first trimester pregnant subjects were randomly allocated to receive standard-of-care prenatal vitamins plus a 10 mg L and 2 mg Z softgel (Carotenoid Group) or standard-of-care prenatal vitamins with a placebo (Controls) for 6 to 8 months.

A significant increase was seen in maternal serum L+Z concentrations, serum total carotenoid concentrations, and skin carotenoid status (p < 0.001, for all) in the Carotenoid Group v the Controls at all time points.

Similarly, infants whose mothers received carotenoids had a 5-fold increase in cord blood L+Z concentrations, over a 3-fold increase in cord blood total carotenoids, and a 38% increase in skin carotenoids compared to the Control Group (p < 0.0001, for all). Also, there was a strong positive correlation between postpartum maternal and infants’ systemic carotenoid status (p < 0.0001). Ocular effects of this intervention in the mothers and their children will be addressed in a forthcoming report.

References

1. L Yang, et al. N-3 polyunsaturated fatty acids in elders with mild cognitive impairment: A systemic review and meta-analysis. J Alz Dis . Online ahead of print Feb 9, 2023.
2. E.K. Addo, et al. Systemic effects of prenatal carotenoid supplementation in the mother and her child: The Lutein and Zeaxanthin in Pregnancy (L-ZIP) Randomized Trial – Report Number 1, J Nutr. S0022-3166(23)72117-2.