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The Importance of Vitamin D

Updated: May 29, 2022

Vitamin D is essential for bone health, but recent research shows a connection between a deficiency of vitamin D and cognitive decline. Vitamin D may also be important for preventing infections, reducing inflammation, and reducing cancer cell growth.

Our body can manufacture vitamin D when we are exposed to sunlight, but many of us may not be getting enough sun to do so. Many of us may need vitamin D supplements to stay healthy.

Vitamin D for Bone Health

Vitamin D is essential for our bone health. It helps us absorb calcium through our intestines to our blood where it then goes to build strong bones.

Even if you have a good level of calcium in your body, if you do not have enough vitamin D, the calcium will not go to build your bones!

When we have low levels of vitamin D, there will be less calcium in our blood. When this happens, our parathyroid glands (4 glands on the thyroid gland) jump into action and produce a hormone to make sure there will be enough calcium in our blood. It does this by taking the calcium from our bones!

For good bone health and to prevent osteoporosis, make sure you are getting enough vitamin D!

Vitamin D Protects Our Brain

Research shows that Low levels of vitamin D may increase cognitive decline:

Low levels of vitamin D were associated with substantial cognitive decline in the elderly population studied over a 6-year period, which raises important new possibilities for treatment and prevention.

A large research study showed that a deficiency in vitamin D can increase the chance of dementia by 50% !

The study found that people with low levels of vitamin D had a 53 percent increased risk of developing dementia and those who were severely deficient had a 125 percent increased risk compared to participants with normal levels of vitamin D.

It saddens me to think about the billions of dollars that go into yearly funding of research for a “cure” for Alzheimer’s Disease and almost no funds go to research prevention. How many people could have prevented having dementia had they checked their vitamin D levels?

Remember that a lack of vitamin D causes the parathyroid glands to take calcium out of our bones which is called hyperparathyroidism. It’s important for me to add here that hyperparathyroidism can cause a type of dementia that may be reversible if the parathyroid gland(s) are treated or removed. I personally know of someone who was living with dementia and returned to her former self after the removal of several parathyroid glands.

Here is one case study that shows the reversal of dementia after parathyroid glands were surgically removed.

The patient was surgically treated, and three parathyroid glands were removed. Parathyroidectomy and lithium treatment resulted in improvement of cognitive functions.

I wonder if anyone has connected the dots. Could a lack of vitamin D be the cause of hyperparathyroidism, and this could lead to cognitive decline or a form of dementia that perhaps is caused by a deficit of vitamin D? I was not able to find this type of research. If someone has heard of it, please let me know.

Again – sadly there are plenty of funds for researching medications, but not for prevention, especially if the prevention may be supplements or nutrition and not medications. Please check both your vitamin D levels and you parathyroid function if you are experiencing memory loss.

Finally, Vitamin D is also a strong antioxidant which is so important for brain health. You can read more about this in my blog: The Delicious Way to Protect our Brains

Vitamin D and Parkinson’s

I want to mention a new, interesting, preliminary clinical study, that was just published. It shows the link between less cognitive decline and higher levels of vitamin D in people who have Parkinson's.

In general the study shows that people with Parkinson's have lower levels of vitamin D then a control group. It also shows that those with Parkinson's who had lower levels of vitamin D also had more cognitive decline.

These findings support the relationship between cognitive impairment and Vitamin D in PD patients.

If you or someone you know has Parkinson’s please consider checking vitamin D levels and supplementing if necessary.

Do We Need Vitamin D Supplements?

I must admit that I was very skeptical about the need to supplement with vitamin D. Since I live in a very sunny country and I run outside, I was sure I was getting enough natural Vitamin D from being exposed to the sun. My family’s pediatrician even told me that when they first started regular testing for vitamin D everyone seemed to be deficient. The doctors thought there must be a mistake in the tests.

Well it was no mistake. In this study the researchers were surprised to find that 75% of the population in Israel had a vitamin D deficiency!

The prevalence of vitamin D deficiency or insufficiency (vitamin D levels for the entire study population was surprisingly high for men and women (79·2% and 77·5%, respectively).

When you live in a sunny country you try to avoid direct sunlight and tend to use sunscreen to prevent skin cancer. This may be the reason for the low vitamin D levels.

Several years ago my blood test showed I have dangerously low levels of vitamin D. By taking supplements regularly, my vitamin D level is now normal and I have found that I am less sick with colds and other illnesses. In the past few years there was a decrease in bone mass and I'm concerned it may have been due to low vitamin D levels.

If you are going to take a vitamin D supplement it is a good idea to first check your vitamin D level with a blood test so your physician can let you know how much vitamin D you need to take.

Please note: Vitamin D is a fat-soluble vitamin and can be dangerous if you take too much over a long period of time.

Vitamin D is an extremely important vitamin, and we should check that we are not deficient in it.

Vitamin D:

  • Is important for bone health

  • May prevent cognitive decline

  • May prevent dementia

  • May help persons who have Parkinson’s prevent cognitive decline

You may not be getting enough vitamins D from exposure to sunlight so you may need to take supplements. Too much vitamin D may be dangerous to our health, so check with your physician to find out the correct amount you need. ---

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