COVID-19 and Pregnancy: Does Vitamin D Help?

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Coronavirus disease 2019 (COVID-19) is a highly contagious respiratory disease that is believed to have originated from Wuhan, China. I am sure you’ve heard of it by now as it is currently ravaging several parts of the world and was recently declared a global pandemic.

Cases of COVID-19 in pregnant women have not been quantitatively documented but there are a number of case by case scenarios currently in public record. Most cases are in China and the United States. There is no evidence that pregnancy increases the risk of severe COVID-19 or even reduces it for that matter. Even so, doctors do recommend that pregnant women take the necessary precautions that everyone else is taking to prevent getting infected. In fact pregnant women should take more precautions as the natural progression of the disease in pregnancy is unknown.

One precaution that has proven successful in the past is getting optimal levels of Vitamin D. Vitamin D is an essential fat soluble vitamin that has been touted as the father of all vitamins. There are only three ways our bodies can receive vitamin D: dietary sources; supplements and fortification; and from UV radiation. Vitamin D naturally occurs in few foods including fatty fish, egg yolk, cheese and beef liver. Foods commonly fortified with vitamin D in the United States are milk and breakfast cereals. Finally, vitamin D can be produced endogenously in the skin, a process that is dependent on UV radiation.

To get adequate vitamin D from this process, you need to sunbathe at least twice a week for 5 to 30 minutes. This process is also dependent on the amount of melanin in one’s skin. Application of sunscreen interferes with synthesis of vitamin D in the skin but most people don’t apply sunscreen, apply insufficient amounts or fail to reapply so this is less of a problem. Furthermore, sun exposure indoors doesn’t count as glass blocks UV rays.

Vitamin D is essential for vital processes in the human body including bone formation and immune function. According to a paper published in 2011 in the journal Vitamins and Hormones, vitamin D activates the immune system. What’s more, a systematic review of meta-analyses showed that vitamin D supplementation decreased the risk of upper respiratory tract viral infections. The meta-analyses have come into focus recently what with the global pandemic that is COVID-19. The evidence states that vitamin D reduces recovery time and severity of symptoms in both pandemic and seasonal flu. The benefits were seen in all patients of all ages and patients with pre-existing conditions.

The best indicator for adequate vitamin D levels in your body is serum concentration of inactive vitamin D, known as 25-hydroxy vitamin D. The reference range is 2 to 50ng/ml with the optimal level being 20ng/ml. The recommended daily intake for pregnant women and lactating mothers is 15 micrograms or 600IU (international units). This is the same recommended daily intake for all adults.

With most countries on lock down or restricting movement, measuring your vitamin D levels may not be possible. In this case, you may want to err on the side of caution by increasing your vitamin D levels. You can do so in 3 ways:

1. Sunbathe

Sunbathe twice a week, perhaps on your balcony for 15 minutes or so, without applying sunscreen. This is a controversial way of getting vitamin D given that UV exposure is a known carcinogen. The risk of skin cancer is associated with duration of exposure. Hence, weigh your options carefully. A little bit of sun exposure once in a while, in the early mornings or late evenings when the sun is not blazing hot may be acceptable. If you don’t want to take any chances, there are safer ways.

2. Eat vitamin D rich foods

Increase your daily intake from food. During this pandemic, make a conscious effort to eat foods rich in vitamin D such as fatty fish and fortified foods like milk and cereals.

3. Take vitamin D supplements

Taking supplements is ideal because you will know exactly how much vitamin D you’re taking as this information is available on the label. It is also a good option for those who want to avoid sun exposure and those on special diets that don’t include meat and dairy products. However, before buying a bottle, be sure to confirm that your antenatal multivitamins don’t already contain vitamin D as too much of it is dangerous. Stick to the recommended daily intake of 600IU.

While there is no evidence that vitamin D will reduce your chances of getting COVID as little is known about the disease, boosting your levels, especially while pregnant, will keep your immune system strong.

Marlene Okoth
Dr. Marlene Okoth is a medical doctor practicing in Nairobi, Kenya. She is also a trained science writer who is passionate about providing clear, concise, lucid and accurate medical information geared towards helping people better their lives. She is particularly keen on impacting the lives of women and children through health education.

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