Vitamin D is known as “The Sunshine Vitamin” for good reason: over 80% of our Vitamin D supply comes from exposure to the sun.   The remainder is found in a few foods, like fatty fish, and in dairy products or juices that are “fortified with Vitamin D.”

Vitamin D is important to good health for many reasons, so it’s easy to see why we’re focused on making sure we get “enough.”   It’s critical for building strong bones, maintaining a healthy heart, and helping to prevent high cholesterol, obesity, diabetes, high blood pressure and gum disease.   Vitamin D is also required to balance calcium and phosphorus in the body, maintain a healthy immune system, and lower the risk of some cancers.

Since so much of our Vitamin D production comes from the sun, it’s deceptively easy to meet your daily requirements – “just 15 minutes a day of being in the sun can create sufficient Vitamin D,” says Dr. Jeffrey Dover, clinical associate professor of dermatology at Yale University School of Medicine.   Just 6 days of casual exposure can make up for 49 days of no exposure – the Vitamin D is stored in fatty tissue and then released as needed.

Vitamin D deficiencies are common among the elderly, and in northern regions of the U.S. and Canada, where days are shorter, and temperatures colder.   However, for people over 65, even in sunny Florida, deficiency rates can reach 40%, as aging kidneys may have trouble converting dietary Vitamin D to a useful form.   And, in very warm climates, people may tend to stay indoors where it’s cool, reducing their time in the sunlight.

Effective Vitamin D production from the sun occurs when UV-B rays hit the skin, and create a reaction that allows the cells to manufacture Vitamin D.   The recommended 15 minutes daily can create as much as 10,000 international units of the vitamin – more than enough to meet the average person’s Vitamin D needs.   Since it’s not something you can “feel,” however, many people overestimate the amount of sun they need to meet their daily needs.   It seems hard to believe that a casual walk on a sunny day for 15-20 minutes could be doing much for Vitamin D needs, so there is a common tendency to overdo the sun exposure.

The risks of overexposure to the sun are well known, ranging from premature aging of the skin to skin discoloration, and even greater risks of skin cancer.   UV rays damage skin fibers, and reduce the elasticity of the skin, over time, causing sagging, loss of texture and tone, increased wrinkles, and slower resilience and healing.     While these outcomes may take many years to become visible, the damage begins at an early age – estimates are that 80% of lifetime sun exposure happens before age 18 — so it’s important to help children develop good sun protection habits early.

Protecting Your Skin From Sun Damage

While sun sensitivity is generally greater for those with fair or freckled skin and light-colored hair and eyes,  risks from overexposure are a concern for everyone.  These simple steps can help protect you from long-term sun damage

  • Avoid the mid-day sun when UV rays are strongest
  • Use SPF 30+ for UVB protection – include zinc oxide to protect from UVA rays
  • Wear sunglasses with UV protection
  • Wear a wide-brimmed hat to protect your face and neck
  • Choose clothing and cosmetic products with sunscreen protection as well
  • Avoid extended exposure, or actual sunburn – use shade, or cover-ups to protect skin

The good news is that there is no solid scientific evidence that indicates using sunscreen prevents Vitamin D production.   So, you can enjoy the sun, build up your Vitamin D stores, and protect your skin all at the same time!


Vitamin D: Uses, Side Effects, Interactions, and Warnings. Retrieved February 27, 2017, from Web MD website:

Time In The Sun: How Much is Needed for Vitamin D? Retrieved February 27, 2017, from U.S. News & World Report: Health website:

Cosmetic Procedures: Sun Exposure and Skin Cancer. Retrieved February 27, 2017, from Web MD website:

Does Sunscreen Block My Body from Getting Vitamin D? Archived: March 20, 2014. Retrieved February 27, 2017, from Web MD Answers website: