The Vital Importance of Vitamin D + How to Choose the Best Supplements for Your Health

If vitamin D were a person, we’d probably classify it as a superhero! 🦸

Vitamin D does so much for your body that it’s kind of hard to keep track!

It’s most commonly known as the sunshine vitamin because you naturally produce it when your skin is exposed to the sun! 😎

But did you know that vitamin D is more than just a vitamin? When it’s in its active form, it’s actually a hormone! 

And we know that hormones are the regulators of the body, helping you maintain balance in all areas of your health. Many hormones are made from cholesterol and in fact, vitamin D needs cholesterol (in the skin) to work. 

I told you vitamin D is a superhero, didn’t I? πŸ˜‰

There’s a whole bunch more to learn, so let’s dive in!

What does Vitamin D do for your body? 

A better question would be, “What doesn’t vitamin D do for the body?”

For starters, vitamin D is needed to help you absorb calcium and phosphorus from the food you eat, ensuring you have strong, healthy bones. 🦴

It also helps ensure you have plenty of calcium available at a moment's notice, most of which is stored in your bones and teeth.  

But that’s not all!

Vitamin D also:

  • helps your body make red blood cells, which are the basis for your immune system
  • regulates and controls inflammation in the body, which directly affects our lung health
  • helps build strong and flexible muscles
  • helps regulate kidney function
  • helps cellular function, reproduction, and differentiation (what kind of cells are made) 
  • improves gene “expression,” which is responsible for making all the other hormones in your body and preventing the growth of cancer and the development of immune-crippling diseases
  • helps regulate the production of adrenaline, norepinephrine (the alertness hormone), and dopamine in the brain
  • helps control infections 
  • keeps you happy and in a good mood and may prevent depression (people with low levels of vitamin D have a higher incidence of depression)
  • helps control your weight (low vitamin D levels interfere with leptin effectiveness, which tells you when you feel full)
  • may help prevent the development of Alzheimer’s by helping the brain get rid of beta-amyloid, the protein believed to cause the disease

Nearly every cell in your body has receptor sites for vitamin D! Whoa! 

The news is clear: We can’t live a full and healthy life without vitamin D. 

How much Vitamin D do you need per day? 

Vitamin D is measured in international units (IU) and micrograms (mcg). 

Recommendations vary, so check with your doctor if you’re concerned or confused about how much you need. 

According to Healthline, the factors that affect how much vitamin D you need daily are:

  • age
  • ethnicity
  • latitude (your location)
  • season
  • sun exposure
  • clothing

The numbers below are general guidelines from The Mayo Clinic as a baseline: 

For children ages 0-1, 400 IU is recommended. 

For adults ages 1-70, 600 IU is recommended. 

For adults ages 70+, 800 IU is recommended. 

You can also reference this awesome chart from Integris Health:

What foods contain Vitamin D? 

Well, truth be told, very few foods contain vitamin D. We’re meant to get it from exposure to the sun. However, nature has a built-in backup plan just in case our sun exposure is less than optimal. 

Here are a few of the best options if your vitamin D needs a little boost:

  • Salmon
  • Other fatty fish such as sardines, herring, and mackerel
  • Cod liver oil
  • Sun-exposed crimini mushrooms
  • Sun-exposed portobello mushrooms
  • Egg yolks
  • Beef liver

Many foods are fortified with synthetic vitamin D which isn’t as great as it sounds. It’s always best to get it from natural sources such as the sunshine or the above-mentioned foods if at all possible. 

How does the sun produce Vitamin D? 

Sheryl Crow said it best when she told us to “soak up the sun!” β˜€οΈ (Bonus points if you know this song!) 

Vitamin D is formed when a steroid called 7-dehydrocholesterol in your skin is broken down by the sun’s UVB (ultraviolet) light. So cool! But this process requires plenty of available cholesterol to work. (Statin drugs can interfere with this process by dropping cholesterol too low.)

This means one thing: You gotta get outside as much as you can. Sitting in a sunny living room or chillin’ in your warm car won’t help because windows block this UVB light. πŸ€”

Cholecalciferol, along with vitamin D-rich foods are converted into vitamin D3 in the liver, producing the inactive form of vitamin D known as 25-hydroxy vitamin D. This is the vitamin D you see on your blood test. But this isn’t the end of the road!

It’s time for your kidneys to step in and make the final conversion of vitamin D into… Wait for it… a hormone! 

Yes, vitamin D in its active form is actually a hormone – and that’s what makes it so miraculous in the body!

Can you have too much Vitamin D in your body? 

In short, yes.

If you can develop a deficiency, you can also have too much vitamin D. 

Most of the time, excess levels of vitamin D come from taking too much in supplement form, not from excess sun exposure. When you have too much vitamin D, it can disrupt the way your body manages calcium leading to a condition called hypercalcemia, which is a build-up of calcium in the blood. 

Hypercalcemia can cause nausea, vomiting, and frequent urination. 🀒 You can also feel bone pain and develop kidney problems, such as calcium or kidney stones. 

So be sure to have your vitamin D tested before taking it! πŸ€“

What are the signs of Vitamin D deficiency? 

Because vitamin D is such a crucial vitamin for optimizing your overall health, knowing the signs of a potential deficiency is key. 

But truth be told, serious deficiency is not very common. People who work indoors or wear clothing that covers most of the skin most of the time, or those who regularly use sunblock (yes, this will prevent vitamin D from reaching the skin), are dark-skinned, obese, aged, or consciously avoid the sun, are at the greatest risk of vitamin D deficiency.

In fact, research shows that vitamin D deficiency has been linked to over 200 diseases! Say what?!

Here are a few symptoms that *might indicate a possible vitamin D deficiency:

😴 Fatigue

πŸ˜‘ Not sleeping well/poor sleep

😣 Bone pain/achiness

πŸ₯Ή Depression or feelings of sadness

πŸ’‡ Hair loss

πŸ’ͺ Muscle weakness

😞 Loss of appetite

😷 Poor immunity/getting sick often

🀍 Pale skin

The only way you’ll know for sure is to do a quick blood test to find out. Your primary care doctor or a functional medicine practitioner can help you determine what your optimal levels should be and make recommendations to help you get there.

How do you choose the right Vitamin D supplement? 

Let’s start with the basics.

There are two (2) types of vitamin D supplements. 

The first is vitamin D2 (ergocalciferol) which is made by plants and is not produced in the human body. 

The second and more well-known is vitamin D3 (cholecalciferol) which is the type made by your skin when exposed to sunlight. This is also the type we get from our food. 

Now, let’s talk about the elephant in the room. 

The supplement industry is not well-regulated. In fact, it’s hardly regulated at all. That means you could very easily be duped into taking something that isn’t great quality or even worse, won’t do you any good. β˜ΉοΈ

This is why you need to become a bit of a detective and use your skills of deduction when choosing any kind of supplement. πŸ•΅πŸΎ‍♀️

Steps for choosing safe and effective supplements:

πŸ” Watch out for bold claims

If a supplement sounds too good to be true, it probably is! Claims that it will cure everything and make you superhuman are definite red flags. 🦸

πŸ§ͺ Read the ingredients

Many supplements contain additives or other unhealthy compounds, neatly disguised as “Other Ingredients” that may block the very nutrients you’re trying to absorb! So be sure to read the label thoroughly. Look for those that are “free from” GMOs, artificial coloring, artificial flavors, wheat, or gluten to name a few.

πŸ’Š Check the recommended dosage

Many over-the-counter supplements are – well, less than potent. The recommended dosage on the bottle is typically quite low meaning you may not get what you need. It’s important to know what the right dose is for your body and then adjust your pill count accordingly. 

πŸ“… Check the expiration date

Supplements always have an expiration date and can lose potency over time. Many online retailers will sell expired supplements to try and get rid of them quickly. Better to purchase them from a local healthcare practitioner who has sufficient training in functional medicine and knows how to work with your condition.

πŸ’Έ Consider the cost

They say, you get what you pay for, and when it comes to your supplements, this is absolutely true. Cheap doesn’t mean better when it comes to your health. The big box stores are looking at profits, not your health. So not to beat a dead horse, but it’s always better to work with someone who knows what’s going on with you and can make the best recommendations possible. 

Vitamin D is a superhero!

You probably already knew it, but vitamin D is essential for maintaining optimal health. It’s integral for your immune system, hormone synthesis, skin health, and so much more. Even your thyroid needs vitamin D to function well.

Your body deserves all the love, attention, and care it can in order to perform well for you. πŸ’—



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“Vitamin D: food, functions, how much do you need & more” | eufic — food facts for healthy choices | Last updated January 11, 2021:

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