Omega-3s and Vitamin D Improve Circulation

DHA and EPA preserve memory. Doctors had thought DHA was the primary omega-3 fatty acid to improve circulation in the brain. This study also supports a role for EPA. In the study, 38 people with borderline high blood pressure, aged 40 to 85, took a placebo or 1,600 mg of DHA plus 400 mg of EPA per day.

After 20 weeks, compared to placebo, women in the omega-3 group saw a 26 percent increase in brain blood-flow response under low-oxygen conditions. In men, the link between brain nerve-signaling activity and increased brain blood-flow became stronger, as levels of EPA in red blood cells increased.

Discussing the findings, doctors said these preliminary observations suggest the omega-3s DHA and EPA may enhance blood flow in the brain in response to low-oxygen situations and cognitive stimulation. (Reference: Nutrients; 2018, Vol. 10, No. 10, 1413)

Vitamin D improves circulatory fitness. Earlier vitamin D studies measuring heart and lung fitness have been inconsistent. In this large, nationally representative sample, doctors measured vitamin D levels in 1,995 people, aged 20 to 49, and compared to their heart and lung fitness.  Researchers used a test of maximum oxygen consumption capacity as the gauge of cardiorespiratory (CR) fitness.

Overall, those with the highest levels of vitamin D had 4.3 times the CR (cardiorespiratory) fitness as those with the lowest levels. Doctors then adjusted for age, gender, race, body-mass index scores, smoking, high blood pressure, and diabetes, and still found a 2.9-times increase in maximum oxygen consumption compared to those with the lowest vitamin D levels. 

As levels of vitamin D increased, oxygen consumption capacity also increased.