Vitamin D: The sunshine vitamin
Vitamin D is produced by the body and absorbed from our diet. To be produced by the body, your skin needs to be exposed to sunlight for roughly 10-20 minutes at a time. The exposure should be without sunscreen and is best if it occurs near midday. The darker your skin, the more sunlight you need to stimulate your body’s natural Vitamin D production.
I know what you’re saying. “But Dr. Simmons, you always tell me to wear sunscreen.” Yes, I recommend sunscreen every day, especially on the face, ears, and arms (the most common places I see skin cancer). However, I know most people don’t cover their entire body with sunscreen. Plus, in today’s world, most people (including me) spend most of their time indoors. If you make an effort to get outside 3-4 days per week, I guarantee you will trigger your body to make natural vitamin D, even with sunscreen and clothes on. Set a goal to go for a walk, bike ride, work in the yard, or swim. Anything that gets you off the couch and outside can help you. Not just with Vitamin D, but many aspects of your health.
Vitamin D from diet
Vitamin D can be found in the foods we commonly consume. These include fish, eggs, and fortified foods (such as cereal, juice, milk, and oatmeal). In Texas, I find that most of my patients eat fish a few times per week, if at all. Many of my patients avoid fish altogether, either because they don’t like it or because someone else in the family doesn’t (especially children). As a result, fish is skipped from our regular home meal rotations. The bottom line: Unless you go out of your way to make sure you are getting enough fish in your diet, chances are you are not getting enough to meet your needs (Spoiler alert: Fish is the main way we consume Omega 3 Fatty Acids). On the other hand, eggs, milk, and cereal are more common in our diets. Focus on eating a variety of foods to round out your diet.
An important note: the Vitamin D you get from your diet is slightly different than the Vitamin D you make from the sun. The body uses each in different ways. Getting both is important to your overall health.
Vitamin D’s multifaceted role in health
Vitamin D often comes up when I am counseling a patient about bone health. However, Vitamin D has been discussed as improving cardiovascular health, muscle repair, mood, immune function, and even cancer detection and cancer destruction. I reviewed over 20 articles, and here are my conclusions.
Vitamin D and Bone Health
There is no doubt that taking vitamin D can improve your bone health. However, the benefits for bones only occur when you take vitamin D with calcium. Vitamin D alone does not affect bone quality, and studies showed no change in falls or fractures from falls in people who took Vitamin D without adding calcium. However, if people took both, there was a 16-33% reduction in fractures from falls. The current guidelines for bone health include taking 500 mg of calcium twice daily and 800 IU of vitamin D3 daily to reduce the risk of fractures. I also ask my clients to buy Vitamin D3 with K2 to help shuttle the calcium absorbed into the bone and away from the heart.
Vitamin D and your immune system
Most people know about Vitamin D and bone health. However, the reason I recommend most of my patients take Vitamin D3 as a supplement is the benefit to the immune system. It is clear that people who take Vitamin D supplementation have fewer infections. This single benefit made Vitamin D a very popular supplement during COVID. However, it has always been important, and people who take Vitamin D have fewer infections and fewer autoimmune disorders.
These two reasons alone are the main reasons I recommend taking Vitamin D, but let’s look at some of the other reasons often discussed.
Vitamin D and heart health.
There is no definitive evidence that Vitamin D supplementation reduces major adverse cardiovascular events. The VITAL trial showed no reduction in heart attacks, stroke, or cardiovascular death, with no benefit even among those who started with a low Vitamin D level. A meta-analysis of 21 studies confirmed no reduction in heart attacks, stroke, death from heart-related issues, or all-cause mortality. This was true regardless of sex or age.
Vitamin D and cancer prevention
Vitamin D supplementation does not reduce overall cancer incidence. The VITAL trial (2,000 IU/day, n = 25,871, median 5.3 years) found no significant reduction in invasive cancer of any type.
However, there is a consistent signal for reduced cancer mortality, particularly with daily dosing. A meta-analysis of 26 RCTs found a 12% reduction in total cancer mortality. This means that anyone with any form of cancer can benefit from Vitamin D.
Vitamin D and mood
There is a benefit to taking Vitamin D and improving our mood. I am guessing most of you know this, since being out in the sun makes us feel better. If you need a prescription for a beach vacation, I am happy to write it.
Summary
Vitamin D has been studied more than most other vitamins. It has proven beneficial for both men and women, as well as children and adults. Basically, everyone can benefit from taking Vitamin D. So, what should you do to make sure you have enough D to keep your mood, bones, and immune system healthy? I recommend that all my adult patients take 1,000 IU of Vitamin D3 with K2, in addition to eating foods fortified with Vitamin D and getting 15-20 minutes of sunlight three times per week.