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Why you probably can’t get Vitamin D from the sun in the winter, and what you can do about it!

Why you probably can’t get Vitamin D from the sun in the winter, and what you can do about it!

(Blog post headlines are very limited in the information they can give. So, therefore, I urge you to read until the end).

So many of us are deficient in Vitamin D, often due to the lack of strong enough sunlight in the wintertime. But did you know, even those in more southern climates are also at risk for Vitamin D deficiency? This is because people are inside much of their daylight hours and do not soak in enough sunshine regularly to have enough of it in their bodies.

First of all, what is Vitamin D, why do we need it, and how do we get it?

Vitamin D was discovered when doctors and researchers were trying to figure out a treatment for rickets, which is a skeletal disorder especially in children that is characterized by delayed growth, pain in spine, pelvic, and leg bones, muscle weakness, and soft and brittle bones. This disorder was detailed by Francis Glisson in 1650, and even known as far back as in antiquity. By 1824, cod liver oil was prescribed by doctors for the treatment of rickets.

It wasn’t until 1906 that it was thought that there were certain essential dietary constituents needed in the prevention of rickets, as well as other conditions, like scurvy. Often it was thought to be that fresh air and sunshine could prevent rickets, but it wasn’t until 1921 that Hess and Unger noticed that seasonal changes in sunlight impacted the incidence of rickets, as well as a team at Vienna University in 1922 observed in their work with children that sunshine, as well as whole milk and cod liver oil, could cure rickets.

Eventually, the essential component needed to cure rickets was called “Vitamin D.” Vitamin D is necessary to properly absorb calcium to prevent rickets, as well as osteoporosis. Low levels of Vitamin D has been associated with higher risk of contracting breast cancer, colon cancer, prostate cancer, heart disease, depression, weight gain, and others.

Vitamin D can be found in a few different types of foods, however, it can be a challenge to get all nutritional needs from food sources alone. One of the best ways to get Vitamin D is from the sun’s UVB rays. These days, researchers are realizing that Vitamin D in behaves more like a hormone than an actual vitamin, and is created in the body when the skin is exposed to sunlight. Again, it's entirely possible for people who consume animal products and who live in sunny locales to not get enough Vitamin D if people are indoors most of the time.

The amount of Vitamin D we can produce in our skin is reliant upon the amount of time spent in the sun, the time of year, where you are located, the altitude, the color of your skin, how much of your bare skin is exposed, and how old you are. In addition, wearing sunscreen and standing behind glass blocks UVB rays from being absorbed by your skin. Although it is common to want to shower after you come in from being outside, it is actually possible to wash off the precursors to Vitamin D.

Why you probably can't “get Vitamin D from the sun” in the winter?

In order to be able to synthesize Vitamin D in your skin, you must be able to get rays that have at least a 3 on the UV Index. We have to remember that we don't merely "get Vitamin D" from the sun, and that it is a reaction and hormone that is produced on and within the skin. If you live in the United States, it takes until April through the end of August where the UV Index is 3 or over for the entire country (except for Alaska). However, those in the central or southern US states will have a much longer UV window, and thus can utilize the sun’s rays for Vitamin D synthesis for a longer amount of time during the year. To see the specific US maps illustrating the UV Index of each month, please go to the US EPA website here.

A very quick and easy tip from the US Environmental Protection Agency is “The Shadow Rule”:

An easy way to tell how much UV exposure you are getting is to look for your shadow:

  • If your shadow is taller than you are (in the early morning and late afternoon), your UV exposure is likely to be lower.

  • If your shadow is shorter than you are (around midday), you are being exposed to higher levels of UV radiation.

My recommendations for managing your Vitamin D levels is to get a blood test taken every year or every other year to check your status. This way, you and your health care provider can work together in appropriate supplementation. I recommend taking Vitamin D3 supplementation if there is a deficiency or you are prone to a Vitamin D deficiency. Vitamin D3 is more readily absorbed by the body than Vitamin D2. The amount of supplementation will vary based on the deficiency you might have. Check when the UV Index is above 3 in your area and get sunlight everyday or every other day by exposing bare skin, without sunscreen, for half the time it takes you to burn. When you have completed your time in the sunlight, cover up with clothing, move into the shade, and put on a natural sunscreen containing zinc oxide, such as Badger brand (Also: Badger Sunscreen with insect repellent and Babo Botanicals Continuous Spray Natural Sunscreen).

As with any of my recommendations, discuss these with medical professional.

Note: This article contains Amazon affiliate links (sunscreen products). If you purchase the products in the link, I will earn a very small commission. I share these products because I have used them before and believe that they my be of benefit to you. I am not an employee or contracted by any of the companies related to the products, nor are these my own personal products for sale. The primary reason for this article is to provide readers with helpful information and not to come up with content solely to sell products.


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