Ask the doctor: Sunscreen and Vitamin D

Q: I heard that Sunscreen causes Vitamin D deficiency.  Is this true?  How do I protect myself?

 

A: The short answer is Yes.

It is true that wearing sunscreen may inhibit the manufacture of Vitamin D.  Studies have demonstrated that when ultraviolet rays are blocked with sunscreen, the amount of Vitamin D that we make is restricted.

sunbathing 300x199 Ask the doctor: Sunscreen and Vitamin D PhotoThe real issue is, how much interference of Vitamin D production with sunscreen occurs and can this reduction actually lead to a deficiency of this important nutrient?

 

Evidence

  • A study performed by the Department of Dermatology in Jefferson Medical College, Philadelphia in 1988 demonstrated that chronic sunscreen usage did decrease circulating levels of vitamin D (as seen in the users, unlike the controls) by as much as ten times
  • However, this study worked with a small amount of subjects.  Results from more contemporary randomized research suggest that the amount decreased is insignificant and that while there is proven interference in production, there is not enough of a decline to actually cause a vitamin deficiency.
  • The National Institute of Health claims that very little sunlight is needed to manufacture sufficient amounts of Vitamin D and suggests that a mere half an hour of unprotected exposure to sunshine twice a week is all that is needed.
  • The chairman of dermatology at Henry Ford Hospital in Detroit, Dr. Henry Lim explains that some sunshine makes direct contact with the skin even when using sunscreen because most people don’t apply the ointment on properly to glean its full therapeutic effect.

 

While there is some reduction in the synthesis of Vitamin D, there is not enough of a risk to suffer from a deficiency.  There is more of a risk to your health in terms of burns, skin irritations and skin cancer so applying sunscreen is very important.

 

Action steps

1) Eat foods rich in Vitamin D. Especially during the summer months, consider adding the following to your diet:

  • Milk
  • Orange juice
  • Yogurt
  • Fatty fish (Salmon, tuna, mackerel)
  • Egg yolks
  • Cheese

 

2) Take a Vitamin D Supplement. Follow RDA guidelines and take a supplement if you’re concerned you don’t get enough Vitamin D.

Children under one have an RDA or 400 IU. Below age 70, take 600 IU. Above 70 years old, take 800 IU.

 

Role of Vitamin D

  • Promotes bone growth
  • Prevents weakened, think, brittle bones
  • Stimulates calcium absorption in the gut
  • Enhances body immunity
  • Decreases risk of cancer

 

So, use your sunscreen, have a healthy diet, take an additional supplement and enjoy the sunshine while you can. See you out there!