The Dynamic Duo of Calcium and Vitamin D

November 17, 2021
Posted by Malcolm Lamb

Winter is coming!

Okay, no need to panic. There’s lots of good things about winter! Christmas, skiing, sipping hot chocolate while bundled up on the couch. We’ve got plenty to look forward to over the next few months.

However, there is one thing about winter which isn’t so great, which is that colder weather often means people don’t get nearly as much vitamin D as they need.

Vitamin D is called the “sunshine vitamin” because it is produced by your body in response to contact with sunlight. In winter, cold weather means thicker layers and more time inside.

So what’s the big deal? Is vitamin D really that important? The answer is yes, for many reasons. This article will focus on the interaction between vitamin D and calcium and how not getting enough can have more effects than you might think.

Calcium

Calcium is the most abundant mineral in the body, making up as much as 2% of your body weight. Most of this calcium is concentrated in the bones. The rest (only about 2%) is found in the blood, extracellular fluid, and various tissues.

When you are not getting enough calcium, your body draws on the calcium in your bones in order to maintain calcium homeostasis. This process weakens the bones and can lead to osteoporosis in the long term if not managed properly.

Though most widely known for its role in bone health (Got milk?), calcium is actually an important factor in important processes such as blood vessel contraction and dilation, muscle function, blood clotting, nerve transmission, and hormonal secretion.

Vitamin D

Studies have shown that up to half of Americans aren’t getting enough vitamin D, and this number can be even higher in non-white people because of how the pigment in their skin reduces the skin’s ability to produce vitamin D from sunlight.

Low vitamin D can lead to many unfavorable health outcomes, one of these being a loss in bone density. But why is this? Why does not getting enough vitamin D have such a profound effect on the health of our bones?

How Vitamin D and Calcium Work Together

For the calcium you consume to actually have an effect, it must be absorbed into your system. This process is enabled by vitamin D. In fact, some studies suggest that without adequate vitamin D, as little as 10-15% of dietary calcium actually ends up being absorbed by the gut.

If you’re putting in effort to make sure that your calcium intake is healthy but you aren’t paying attention to your vitamin D, then your benefits are going to be lessened.

Remember that when we’re not absorbing enough calcium, our body begins to draw on the calcium stores in our bones to compensate. This not only weakens existing bone but inhibits the formation of strong, new bone.

One study performed on elderly patients, adding vitamin D to the patients’ diets reduced the incidence of hip and other fractures by 20-39%. On another occasion, researchers observed that calcium and vitamin D taken together led to a 29% reduction in relative risk of hip fractures.

Natural Sources of Vitamin D and Calcium

Calcium

Milk
Cheese
Yogurt
Fortified Orange Juice
Fortified Soymilk
Salmon
Sardines

Vitamin D

Vitamin D-fortified Milk
Egg yolks
Cod Liver Oil
Wild Caught Salmon
Farmed Salmon (significantly less vitamin D than Wild Caught Salmon)
Tuna
Trout

Wrapping Up

So there you have it!

The connection between vitamin D and calcium is a powerful one. It shows that our health isn’t just about picking and choosing. We need to take a big-picture approach if we really want to feel our best.