Surprising findings elevate vitamin D’s importance; Many women don’t realize their heart risk 02/27/2018
Today, we’ve got news— good and bad — about heart-health.
We’ll start with the good news, which involves the effects of vitamin D3 on the specialized tissue that enfolds and lines our blood vessels.
Before we describe the good news about vitamin D3, let’s explore the critical roles that this relatively obscure tissue plays in cardiovascular health.
The endothelium: Little-known, but critically important
You’ve probably heard that the skin is the biggest organ in the human body.
That’s a myth, whether you measure people's organs by weight or surface area.
Our lungs cover much more surface area — about the size of a tennis court — and our muscles make up a far larger proportion of body weight.
And few folks are familiar with what some consider one of the largest “organs” in your body — the endothelium.
The endothelium is the wrapper that encloses all 60,000 miles of your vascular system, from the major coronary arteries to tiny capillaries at the tips of your toes.
Aside from that structural role, the endothelium serves as the interface between your circulatory system and the rest of your body — and regulates or influences key aspects of cardiovascular health:
- Vascular tone.
- Proper blood clotting.
- Blood flow and blood pressure.
- Blood vessel flexibility and resistance to plaque buildup.
- Passage of water and electrolytes in and out of the bloodstream.
Over time, the endothelium begins to degrade, due to inflammation, stress, poor sleep, infections, and oxidative (free radical) damage caused by unhealthful diets, lifestyles, and environments.
The endothelium can also be harmed by vitamin deficiencies — especially by shortages of vitamins D and vitamin B12.
One of the endothelium’s key roles is to regulate the secretion of nitric oxide, which in turn regulates vascular tone, inflammation, and clotting.
When the endothelium is damaged, nitric oxide secretion drops, which promotes hardening of the arteries (atherosclerosis) and high blood pressure.
And lack of nitric oxide in the vascular system when it's needed promotes diabetes, stroke, and certain autoimmune diseases, including rheumatoid arthritis and Parkinson’s disease.
Until recently, it hasn’t been clear whether nutritional or lifestyle changes could kick-start or accelerate endothelial healing.
But previous research suggested that vitamin D3 — as well as foodborne antioxidants — can help protect cardiovascular health.
Vitamin D3 — the form preferred by the body — is produced by sun exposure, and otherwise abounds only in fatty fish and supplements. (The body can benefit from the vitamin D2 found in mushrooms and some other plant foods, but gets more benefit from D3.)
Cardiologist Erin Michos, M.D., is Associate Director of Preventive Cardiology at Johns Hopkins Medicine, where she specializes in women’s heart health and vitamin D for heart health.
As Dr. Michos says, “A growing number of studies point to vitamin D deficiency as a risk factor for heart attacks, congestive heart failure, peripheral arterial disease (PAD), strokes, and the conditions associated with cardiovascular disease, such as high blood pressure and diabetes.”
Now, promising findings from a new study suggest that raising vitamin D3 in the blood to optimal levels — via sunshine or diet — may help keep your arteries young at heart.
The good news: Vitamin D3 may help heal or prevent cardiovascular problems
Ohio University scientists employed groundbreaking new methods to study the effects of vitgamin D3 on endothelial cells.
And the results strongly suggest that optimal levels of vitamin D3 can enhance endothelial health and performance throughout your vascular system (Khan A et al. 2018).
The Ohio team found that that vitamin D3 can significantly reverse endothelial damage caused by high blood pressure, diabetes, hardening of the arteries and other disease states.
They used nanosensors — microscopic sensors about 1,000 times smaller than a single human hair — to examine how vitamin D3 impacts individual endothelial cells.
The nanosensors revealed that vitamin D3 facilitates release of nitric oxide, which, as we said, plays crucial roles in the regulation of blood flow and prevention of clots.
Somewhat surprisingly, they also saw that vitamin D3 acts as a powerful antioxidant that significantly reduces oxidative (free radical) stress in blood vessels — a key promoter of damaging arterial inflammation.
And, encouragingly, direct treatment of blood vessels with vitamin D3 significantly restored the kind of damage caused by high blood pressure, atherosclerosis, and diabetes — effects that should reduce the risk of heart attacks, stroke, and other adverse cardiovascular events.
As study co-author Dr. Tadeusz Malinski said, “… many patients who have a heart attack will have a deficiency of D3. It doesn’t mean that the deficiency caused the heart attack, but it increased the risk of heart attack.”
He also made this critical point: “There are not many, if any, known systems which can be used to restore cardiovascular endothelial cells which are already damaged, and vitamin D3 can do it. This is a very inexpensive solution to repair the cardiovascular system. We don’t have to develop a new drug. We already have it.”
We should note that in cell studies, statin drugs exert similar benefical effects on endothelial function, but they come with side effects, and without (except anti-inflammatory effects) the broad health benefits of vitamin D3 (Heeba G et al. 2009).
Johns Hopkins cardiologist Erin Michos expressed both hope and appropriate caution: “Now that we have identified this risk factor for heart disease, the question is, if you’re deficient and I give you vitamin D back, can I actually prevent a heart attack?”
As she noted, that question can only be answered definitively by the conduct of large clinical trials, which are quite costly.
The new Ohio University findings should help gain funding for the needed trials, because they show that vitamin D restores healthy endothelial functioning — and they reveal much about how the hormone-like nutrient performs that feat.
Although this study only examined the effects of vitamin D3 on isolated endothelial tissue, its results raise hopes that the “sunshine-and-seafood” vitamin can become a powerful cardiovascular ally, both for prevention and treatment.
Here’s how Ohio University characterized the study’s encouraging implications:
“The authors suggest that vitamin D3 may be of clinical importance in the restoration of dysfunctional cardiac endothelium ... [and] ... several clinical studies indicate that vitamin D3 at doses higher than those currently used for the treatment of bone diseases, may be highly beneficial for the dysfunctional cardiovascular system.”
The bad news: Women's heart risks run higher in some cases — and they underestimate overall risks
Two new studies — a poll comissioned by CVS Pharmacy, and a population study by Yale researchers — delivered negative news about women and heart health.
Study #1: CVS Poll
The results of a new poll show that most American women don’t know their risk for heart disease and stroke.
The new online poll — which questioned more than 1,000 women and was commissioned by CVS Pharmacy — found that more than half (60%) of the respondents didn’t know their blood sugar levels, cholesterol numbers, or body mass index.
Leaving these risk factors unchecked sharply limits a woman’s ability to take an active role in preventing cardiovascular disease.
More than 90% of the respondents knew that heart-related disease poses a serious threat to overall health, and about 35% said they had a heart-related condition, including high cholesterol, high blood pressure or history of stroke.
Nonetheless, even though heart disease is the #1 killer of women in America, only 18% of the women polled consider heart disease their greatest health threat.
That misperception of risk probably flows from most women’s very understandable — and more visceral — concerns about breast and ovarian cancer.
According to the American Heart Association, one of the key contributing factors to the high rate of heart disease in women over 65 is their greater likelihood of having one or more risk factors in the years leading up to developing cardiovascular disease.
Study #2: Yale study of large British population
A newly published Yale study compared the physical characteristics of nearly 500,000 British adults aged 40-69 to their heart-health records .
The results revealed that women with a large waist circumference and a high waist-to-hip ratio were at greater risk than men possessing similar body proportions.
As lead author Sanne Peters, Ph.D., wrote “Our findings support the notion that having proportionally more fat around the abdomen (apple shape) appears to be more hazardous [for women in particular] than more visceral fat, which is generally stored around the hips (pear shape).”
Recently, researchers at the Yale School of Medicine reported that women tend to suffer more after a heart attack due to worse health prior to the event.
They found that — compared with similar-aged men who’d suffered a heart attack — women had worse physical and mental health and greater physical limitations prior to suffering a heart attack (Peters SAE et al. 2018).
And. compared with men, women were more likely to have other conditions associated with heart disease, including diabetes, obesity, history of stroke, heart failure and kidney failure.
Alongside the “traditional” risk factors for heart disease, research has revealed some women-specific risk factors:
- Higher blood pressure during menopause
- Relatively high testosterone levels before menopause
- Depression and stress, which are more common among women
- Autoimmune diseases, which are more common in women than in men
The message seems quite clear.
Women need to get tested so they know their cardiovascular numbers — so they can pursue proven lifestyle and medical paths to better ones!
- American Heart Association. Heart Attack Risk Factors: Women vs. Men. Sept. 16, 2013. Web. 12 Mar. 2017. Accessed at https://www.goredforwomen.org/about-heart-disease/heart_disease_research-subcategory/heart-attack-risk-factors-women-vs-men/
- American Heart Association. Know your numbers? Accessed at https://www.goredforwomen.org/fight-heart-disease-women-go-red-women-official-site/know-your-risk/know-your-numbers/
- Beal J, Ossorio A. Endothelial Health and Maintenance. CSSVI Alliance. Accessed at http://www.ccsvi.org/index.php/helping-myself/endothelial-health
- Heeba G, Hassan MK, Khalifa M, Malinski T. Adverse balance of nitric oxide/peroxynitrite in the dysfunctional endothelium can be reversed by statins. J Cardiovasc Pharmacol. 2007 Oct;50(4):391-8.
- Heeba G, Moselhy ME, Hassan M, Khalifa M, Gryglewski R, Malinski T. Anti-atherogenic effect of statins: role of nitric oxide, peroxynitrite and haem oxygenase-1. Br J Pharmacol. 2009 Apr;156(8):1256-66. doi: 10.1111/j.1476-5381.2009.00125.x. Epub 2009 Feb 18.
- Khan A, Dawoud H, Malinski T. Nanomedical studies of the restoration of nitric oxide/peroxynitrite balance in dysfunctional endothelium by 1,25-dihydroxy vitamin D (3) - clinical implications for cardiovascular diseases. Int J Nanomedicine. 2018 Jan 19;13:455-466.
- Melamed ML, Michos ED, Post W, Astor B. 25(OH) Vitamin D Levels and the Risk of Mortality in the General Population. Archives of Internal Medicine 2008:168;1629-37.
- Michos ED, Blumenthal RS. How accurate are 3 risk prediction models in US women? Circulation 2012,;125(14):1723-6. PMID: 22399534
- Michos ED, Carson KA, Schneider ALC, Lutsey PL, Xing L, Sharrett AR, Alonso A. Coker LH, Gross M, Post W, Mosley TH, Gottesman RF. Vitamin D and Subclinical Cerebrovascular Disease: The Atherosclerosis Risk in Communities Brain Magnetic Resonance Imaging Study. JAMA Neurol. 2014; 71(7):863-71.PMID: 24861877
- Michos ED, Nasir K, Braunstein JB, Rumberger JA, Budoff MJ, Post WS, Blumenthal RS. Framingham Risk Equation Underestimates Subclinical Atherosclerosis Risk in Asymptomatic Women. Atherosclerosis 2006; 184:201-6. PMID:15907856
- Michos ED, Reis JP, Post WS, Lutsey PL, Gottesman RF, Mosley TH, Sharret AR, Melamed ML. 25(OH)D deficiency is associated with fatal stroke among whites but not blacks: The NHANES-III linked mortality files. Nutrition 2012 Apr;28(4):367-71. PMID:22261577
- Michos ED, Streeten EA, Ryan KA, Rampersaud E, Peyser PA, Bielak LF, Shuldiner AR, Mitchell BD, Post W. Serum 25-hydroxyvitamin D levels are not associated with subclinical vascular disease or C-reactive protein in the Old Order Amish. Calcific Tissue International 2009 Mar;84(3):195-202, PMID:19148561.
- Michos ED. Vitamin D and the Heart. Johns Hopkins Medicine, The John Hopkins University, 13 May 2016. Accessed here.
- Mosca L et al. American Heart Association Evidence-Based Guidelines for Cardiovascular Disease Prevention in Women: 2007 Update. Expert Panel/Writing Group. Circulation;115(11):1481-501, PMID:17309915.
- Peters SAE, Bots SH, Woodward M. Sex Differences in the Association Between Measures of General and Central Adiposity and the Risk of Myocardial Infarction: Results From the UK Biobank. JAMA. 2018;7:e008507. Originally published February 28, 2018. https://doi.org/10.1161/JAHA.117.008507
- Rajendran P, Rengarajan T, Thangavel J, et al. The Vascular Endothelium and Human Diseases. International Journal of Biological Sciences. 2013;9(10):1057-1069. doi:10.7150/ijbs.7502.
- Schneider ALC, Lutsey PL, Alonso A, Gottesman RF, Sharrett AR, Carson KA, Gross M, Post WS, Knopman DS, Mosley TH, Michos ED. Vitamin D and Cognitive Function and Dementia Risk in a Biracial Cohort: the ARIC Brain Ancillary Study. Eur J Neurol. 2014;21(9):1211-8, e69-70. PMID: 24846449