Do you feel overwhelmed? By the deluge of information, the capricious nature of COVID-19, the uncertainty about our future?

Of course you do!

It’s completely normal. Some of you may feel okay. Maybe you enjoy working from home, maybe you’re financially stable, and you don’t have children to look after.

However you’re feeling….It’s okay. Our reactions to this situation will all be different because we’re in different situations.

In the midst of chaos, there are some things you can do to stay healthy and sane. Taking small actions each day to keep yourself healthy go a long way towards your health. 

These tips are backed up by science, and don’t require medical intervention. 

Much about the COVID-19 virus is unknown. But we also know quite a lot. Using this knowledge to inform our everyday behavior is important. I’m not going to bore you telling  you about hand washing or social distancing. 

For the next few weeks or even months, I'll send you simple health tips to keep you healthy and happy, whether your at home or slowly transitioning to work. This first post focuses on Vitamin D and its surprising role in the regulation of blood pressure.

Vitamin D is more than just a vitamin. Categorized as a steroid hormone along with estrogen, testosterone and cholesterol, it’s much more powerful than you might think. Steroid hormones are hydrophobic, meaning that they can enter cells without a receptor and can directly influence gene expression (1). 

The role of Vitamin D plays an important role in the regulation of calcium and also in the regulation of gene expression. Vitamin D regulates the levels of calcium and phosphorus and the mineralization of bone. We can get some vitamin D2 from the diet in egg yokes and fish oil and some plants. A form of vitamin called D3 is generated in our skin when sunlight hits. Both D2 and D3 must be further metabolized by the liver and kidneys to the active form 1,25-dihydroxycholecalciferol. What’s interesting in light of the current epidemic, is it’s role in the regulation of the Renin-Angiotensin System (2). 

Fasten your seatbelts, for a nerd safari through the Renin Angiotensin System. Try to get through the technical details, it will help your understanding of Vitamin D. 

The Renin Angiotensin system regulates the body’s blood pressure through a cascade of events. The kidneys secrete renin in response to one of three signals: decreased stretch on the afferent arteriole walls (sensing low blood pressure), decreased sodium concentration in the blood, or sympathetic stimulation (fight or flight response). 

Renin converts angiotensinogen to angiotensin I which is biologically active, then an enzyme called angiotensin converting enzyme (ACE) converts angiotensin I to angiotensin II. High levels of angiotensin II causes water and sodium reabsorption in the kidneys (via aldosterone) and vasoconstriction.  Vasoconstriction in the small arteries in your body causes your blood pressure to increase. Angiotensin II raises your blood pressure. It’s also associated with inflammation and other negative outcomes, especially with COVID-19 through increased vascular permeability allowing fluid accumulation, neutrophil accumulation ultimately leading to lung injury (3)

The ACE2 receptor has gained recognition lately.  ACE2 is an enzyme that is embedded in the membrane of cells all over the body, especially in the lungs, heart and kidneys. It’s the entry point for the SARS-2 virus into the cell where it can replicate and infect our cells. The spike protein of the coronavirus binds to the active site on the ACE2 Receptor. 

The ACE2 is a good guy in terms of other outcomes. The ACE2 can convert Angiotensin II into Angiotensin 1,7 which causes vasodilation and lowers blood pressure. Ace2 reduces the inflammation caused by Angiotensin II.  Low levels of ACE2 on our lung cells are correlated with more severe symptoms from COVID-19 (3).

So interestingly, the same enzyme that lets the virus into our cells helps to promote better outcomes in terms of inflammation and blood pressure. 

Vitamin plays an important role in keeping  balance in the Renin-Angiotensin  system. Vitamin D impacts this pathway by blocking renin at the start of the pathway. Studies show that oral supplementation of vitamin D led to a decrease in the blood pressure in individuals with diabetes mellitus. A number of epidemiological studies have also shown an inverse relationship between blood pressure and plasma Vitamin D levels (1)

We all want our RAS to be in balance, and Vitamin D helps to maintain this balance by downregulating the expression of renin. If you remember from above, Renin sits at the top of the pathway that produces Angiotensin II. 

Other studies are noting the relationship between obesity, lower plasma Vitamin D levels and worse COVID-19 outcomes (2). While these studies don’t establish causation, there is interesting correlation between lower vitamin D levels and more severe COVID-19 outcomes.