An estimated 42% of Americans are vitamin D deficient, according to the NHANES data from the Second Nutrition Report!

Because the sun is the primary (and best) source of vitamin D, a good portion of the country has trouble getting enough sun exposure for our bodies to produce the amount of vitamin D it needs.  Residents of northern states that experience cloudy springs and autumns, and then cold, snowy winters often have difficulty getting their necessary vitamin D fix.

Before we go on, let’s clear one thing up — vitamin D isn’t actually a vitamin. It’s a fat-soluble hormone that our bodies are able to make on their own but if we can’t make enough we may need to turn to supplements to meet daily requirements.

Vitamin D Deficiency Symptoms

Vitamin D deficiency often goes unnoticed because the symptoms can be quite subtle and can be explained in other ways, such as insufficient sleep, stress, or overexertion. However, it is easily diagnosed with a blood test.

What Does Vitamin D Do for Our Bodies?

Supports Bone Health

Vitamin D is crucial for our bodies in many ways — the biggest of which may be bone health. Vitamin D is necessary for the body to absorb calcium, which is what helps keep bones strong and healthy. Without enough vitamin D, the body may not be able to absorb the calcium it needs from the foods we eat to maintain healthy bone structure. Over time, this pattern can lead to brittle bones.

Supports Muscle Health

In addition to supporting strong bones, vitamin D supports muscle health. Researchers have been studying this for the better part of the past couple decades. 

Even back in 2010, the idea that the “sunshine vitamin” could affect skeletal muscle was well established, with the medical research community citing recent findings in their own papers: “Vitamin D status is positively associated with physical performance and inversely associated with risk of falling. Vitamin D supplementation has been shown to improve tests of muscle performance, reduce falls, and possibly impact on muscle fiber composition and morphology in vitamin D deficient older adults.”

Supports Immune Health

Vitamin D helps support our immune system. While the medical community largely agrees with this assertion, the exact way in which it supports immunity requires additional research. What we do know is that vitamin D deficiency has been linked to multiple ailments — meaning that many patients experiencing specific diseases also had a vitamin D deficiency. 

It’s important to note that vitamin D deficiency does not cause disease. The implication in the data says that sufficient serum levels of vitamin D support the body’s natural ability to fight off diseases. Therefore, if a person’s levels are low, they may not be able to fight off particular infections or diseases. Coupled with poor nutrition, lack of quality sleep, and high stress (i.e. most Americans), a vitamin D deficiency can cause a host of problems.

Supports the Nervous System

The final major role vitamin D plays in the body involves the central nervous system — it helps carry messages from the brain to the rest of the body. In a 2019 review, researchers set out to clarify how exactly this might work (or not work).

Researchers concluded that “the studies reviewed show that [vitamin D] contributes to cerebral activity in both embryonic and adult brain, helping the connectivity of neural circuits responsible for locomotor, emotional and reward-dependent behavior.” However, they also noted that more research is necessary to understand the effects of vitamin D supplementation in brain disorders.

Sources of Vitamin D

Vitamin D is not particularly potent from food sources (nor is it present in many foods at all). Examples include: 

• Cow’s milk

• Almond milk

• Oat milk 

• Any other milk substitutes that specifically say they’re fortified with vitamin D

Other dietary sources of vitamin D include:

• Fatty fish (mackerel, salmon, tuna)

• Beef liver

• Egg yolks

Supplements are a reliable source of vitamin D, especially for those who live in cold climates. In fact, for a significant portion of America, taking a vitamin D supplement is the only way to keep levels where they need to be for optimum health.

Vitamin D for Optimal Health

Vitamin D is critical for many different functions in the body. Deficiencies are so problematic that it’s now considered to be a public health crisis. Getting serum levels checked is very simple and is often combined with regular bloodwork.

A lot of the symptoms of vitamin D deficiency can also be feeling overwhelmed in general. Here are 6 ways to reduce overwhelm and relax