NMU 111 – Study Explains How Vitamin D Improves Cardio Fitness and Helps Prevent High Blood Pressure and Stroke

Nutrition / Natural Medicine Update No 111 (November 1, 2018)

with Dr. James Meschino

Topic: Study Explains How Vitamin D Improves Cardio Fitness and Helps Prevent High Blood Pressure and Stroke

Source: International Journal of Nanomedicine (January 2018)

The research I’m citing today was published in the International Journal of Nanomedicine in January 2018. The study helps explain the relationship we have seen in previous studies between higher blood vitamin D levels and lower risk of developing high blood pressure, as well as improved heart function and a higher level of cardiorespiratory fitness in those with higher blood vitamin D levels. As well, a 2017 study published in the Journal of Clinical Diagnostic Research reviewed the studies showing that lower vitamin D levels increase the risk of stroke and that providing stroke patients with vitamin D in the first number of days after a stroke (to help them attain more optimal blood levels) was shown to result in better functional outcomes in three months, with fewer deaths and disabilities. To date, two vitamin D intervention studies have been undertaken with stroke patients, and both have shown impressive outcomes.

So, how does vitamin D help guard against high blood pressure and stroke and improve cardiorespiratory fitness? In the 2018 study researchers were able to show that vitamin D increases the release of nitric oxide from the cells that line the inner blood vessel wall. This is one of the ways vitamin D is postulated to help improve cardiovascular health. It’s known that nitric oxide is required to dilate (or open-up) blood vessels to allow more blood to circulate. In turn, this reduces the resistance to blood flow, which helps to keep diastolic blood pressure from rising. The decreased resistance to blood flow also means the heart muscle does not have to pump as hard to push the blood through the system, and this helps to prevent a rise in systolic blood pressure. Increased dilation of arteries also brings more oxygen and nutrients to the exercising muscle, which likely explains the superior cardiorespiratory fitness found in people with higher blood vitamin D levels, after all other factors are controlled for. Blood vitamin D levels at or above 32.4 ng/ml (81 nmol/L) have been shown to be associated with a lower risk of developing high blood pressure. These findings were discovered upon data analysis of the large National Health and Nutrition Exam Surveys, and showed that after controlling for other critical factors, including age, sex, race, smoking, alcohol intake, BMI (overweight) , physical inactivity, diabetes, total cholesterol: HDL ratio, C-reactive protein and kidney function (glomerular filtration rate) and others, that simply having higher blood vitamin D levels was associated with better cardiovascular fitness performance and reduced risk of developing high blood pressure.

The 2018 study in the International Journal of Nanomedicine suggests that at least some of these results are made possible via the action of vitamin D on stimulating the release of more nitric oxide from the cells that line the blood vessels. In turn, this opens the blood vessel up, allowing more blood to flow and lowering resistance to blood flow that otherwise causes blood pressure to rise. So, if you haven’t done it yet, see your doctor and get your blood vitamin D level evaluated. The goal is to achieve a blood vitamin D level at or above 30 ng/ml or 80 nmol/L.  Of course, you need to guard against vitamin D toxicity, so you don’t want your vitamin D level to be higher than 100 ng/ml or 250 nmol/L. It does appear, however, that having an optimal vitamin D blood level is one more way to support and enhance your cardiovascular health.

I have included the featured research paper in the text below as well as links to other studies showing the relationship of vitamin D to cardiorespiratory fitness and lower risk of developing high blood pressure and stroke.

References:

1. Khan A, Dawoud H, Malinski T. Nanomedical studies of the restoration of nitric oxide/peroxynitrite balance in the dysfunctional endothelium by 1,25-dihydroxy vitamin D3- clinical implications for cardiovascular disease. International Journal of Nanomedicine. 2018. Vol 13: https://www.dovepress.com/nanomedical-studies-of-the-restoration-of-nitric-oxideperoxynitrite-ba-peer-reviewed-article-IJN

2. https://www.medicalnewstoday.com/articles/320802.php

3. Vitamin D and Stroke: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5376887/

4. Vitamin D and Higher Cardiorespiratory Fitness: http://journals.sagepub.com/doi/10.1177/2047487318807279

5. Vitamin D and Prehypertension Risk: https://www.healio.com/endocrinology/news/online/%7B765aa8d6-1144-4dba-b1fc-3b92a1e186f4%7D/prehypertension-linked-to-low-vitamin-d?utm_source=TrendMD&utm_medium=cpc&utm_campaign=Healio__TrendMD_1

Eat Smart, Live Well, Look Great,

Dr. Meschino