We have known for some time that adequate blood levels of vitamin D are related to better bone health, but more recent research has revealed that elevated blood levels of vitamin D may also be related to:
- decreased risk of various cancers, such as that of the colon, breast, and prostate,
- lesser incidence of certain chronic diseases, including cardiovascular disease, multiple sclerosis, type 1 diabetes mellitus, and rheumatoid arthritis,
- lower blood pressure,
- stronger immune system, and
- overall heart health
If you’re anything like me, this information has prompted in you an entire flood of questions. Well wonder no longer. A few common questions are answered below:
How can vitamin D do all that?
Vitamin D travels in our body via our blood system and acts on any cell that has a vitamin D receptor. Almost every one of our cells contains vitamin D receptors, which means vitamin D can act on organs and tissues throughout our entire body. Once inside our cells, vitamin D interacts with our genes, influencing genetic expression and, thus, our health.
What foods contain vitamin D?
While vitamin D is not plentiful in a wide variety of foods, many types of fish are good sources of vitamin D including salmon, mackerel, and sardines. In addition, some foods now come in varieties that are fortified with vitamin D including orange juice, bread, and cereal (look on the nutrition label or in the ingredient list to check whether a food is fortified or not). Of course, the easiest and most potent source of vitamin D isn’t a food at all – it is the sun!
How is the sun a source of vitamin D?
Our skin is able to synthesize vitamin D in response to sun (UVB) exposure. Isn’t that amazing?! Experts currently believe that it takes only a quarter of an hour or less of unprotected sun exposure for an individual to synthesize an adequate level of vitamin D. And for all of you out there that live far from the equator and don’t get to experience the sun’s rays year-round, rest peacefully knowing that our fat cells store any extra vitamin D we may take in or synthesize to be used, quite literally, for a rainy (or perhaps snowy) day.
Finally, know that:
- The research on Vitamin D is still a growing field and that the above-mentioned relationships between vitamin D and health outcomes are not yet accepted with 100% certainty.
- While vitamin D deficiency can cause rickets in children and osteomalacia in adults, Vitamin D can be toxic to our body if present in the body at too high of levels, so taking prescription-level doses of vitamin D is not recommended unless you’re advised to do so by your doctor.
As with most things in life, moderation is key to reaping the potential benefits of this intriguing vitamin. And, should you have questions concerning vitamin D, your friendly, local Registered Dietitian is always a great place to start!
Do you know of any tasty ways to incorporate salmon, mackerel, or sardines into your diet? We would love to hear about them below!
An Intern behind the Plate,