Vitamin D is an essential nutrient for fertility, pregnancy, and overall health. The deficiency of this vitamin is widespread, and new research is discovering associations between low vitamin D and many health conditions previously not connected to this nutrient. Most recently, immunity and neurological health have been a hot topic associated with vitamin D status. Research finds that this vitamin is crucial in defense against viruses and healing when ill. Additionally, there is a unique interplay between vitamin D status, neurocognitive function, mood, and emotions. New research investigates the connection between vitamin D status during pregnancy and for the general adult and neurodevelopment and neuropsychological conditions later in life.
What Is Vitamin D, And Why Do I Need It?
According to the National Health and Nutrition Examination Surveys, one out of every four Americans were considered at risk for vitamin D inadequacy (less than or equal to 49nmole/L) between 2001 and 2006. This sunshine vitamin is a fat-soluble vitamin that can be obtained from UV sun exposure, found in plant sources such as mushrooms, or animal sources such as milk, egg yolk, and liver.
In this article, we will dive a bit deeper into new research surrounding vitamin D, in particular looking at
- Absorption and utilization of vitamin D
- Vitamin D and immunity
- Vitamin D and neurological health
Vitamin D In Action: What Does It Do In The Body?
There are two forms of vitamin D that we can get exogenously from outside sources; vitamin D2, ergocalciferol, found in plants such as mushrooms, and vitamin D3, cholecalciferol, found in animal products such as milk and eggs, and synthesized in the skin from UV sun exposure.
In order to synthesize vitamin D from your skin, your body needs cholesterol. Once the UV light hits your skin, 7-dehydrocholesterol converts to D3. Vitamin D3 must then bind to a special transporter to move it through the bloodstream and reach various cells and organs. This transporter is called vitamin D binding protein (DBP).
Once attached to this transporter, D3 is brought to the liver, where an enzyme called 25 hydroxylases adds a hydroxyl group to D3 to get 25-hydroxycholecalciferol, or calcidiol.
Finally, it goes to the kidneys, where it adds carbon to make 1, 25 dihydroxy-cholecalciferol, calcitriol; this is the active form of vitamin D.
Did you know? The active form of vitamin D, D3, can act in part of the small intestine called the duodenum to increase calcium absorption, resulting in elevated calcium blood levels.
Vitamin D For Immunity
There has been a lot of hype around vitamin D and immunity since Covid-19 started, so let's dive in deeper to explain this process a little more.
The less bioactive form of vitamin D produced in the liver, calcidiol, can act on immune system cells such as white blood cells. These white blood cells have an enzyme on them that can convert the less active form of vitamin D, calcidiol, to the active form of vitamin D, calcitriol. This means our immune system can activate vitamin D just like the kidneys!
The active form can act on a vitamin D receptor protein in the white blood cell, which can activate particular genes in the DNA. This process can synthesize anti-microbial proteins which support and defend your immune system. This means if you have decreased vitamin D, you can have reduced destruction and less protection from a virus.
Not only does this action happen in your body, but new research also shows that this can transfer to the fetus during prenatal development. Maternal vitamin D status is attributed to protection against early-life infection and even onset of asthma. Furthermore, research finds that epigenetic modifications caused by vitamin D status in utero can affect long-term health outcomes such as the increased risk for autoimmune diseases and even obesity!
Vitamin D For Neurological Development, Mood, And Cognitive Function
A growing body of evidence suggests vitamin D plays a fundamental role in brain development and neurotransmission. Much of this new research finds that inadequate vitamin D is related to various psychiatric diseases. In 2013, a study found that more than 50% of psychiatric patients were insufficient in vitamin D. Specifically, anxiety disorders, depressive disorders, and schizophrenia studies have found significant inverse relationships between levels of serum vitamin D and symptoms of the diseases.
The neurotransmitter serotonin has been widely studied and associated with many psychological conditions, including depression and anxiety. Calcitriol, D3, is the bioactive precursor to serotonin synthesis, mediated by tryptophan hydroxylase-2. Additionally, some exciting mechanisms investigating vitamin D and the gut-brain axis have warranted valuable findings.
Along with neurotransmitter regulation and synthesis, research finds that vitamin D status plays a vital role in regulating oxidative stress and inflammation. Low vitamin D levels have been associated with increased oxidative stress for adults, and this oxidative stress is also present in the fetus if maternal levels are low. This relationship has been linked to the development of brain tissue structure and function in utero, causing both long-term and immediate health effects. In conjunction with neurotransmitter function, low maternal vitamin D can cause impaired dopamine turnover, resulting in even more oxidative stress. This impaired dopamine turnover and oxidative stress caused by low vitamin D is associated with autism spectrum disorder and attention deficit disorders into adulthood.
Did you know: Certain genetic variants within the CYP2R1 and CYP24A1 genes increase the risk of vitamin D deficiency.
Vitamin D is an essential nutrient for fertility, pregnancy, and overall health. The deficiency of this vitamin is widespread, and new research is discovering associations between low vitamin D and many health conditions previously not connected to this nutrient. Most recently, immunity and neurological health have been a hot topic associated with vitamin D status.
Research finds that this vitamin D status affects not only your immunity but also your baby's immunity and long-term health. The specific tissues where vitamin D can be activated are still under ongoing research, and its role in gene expression is ever-evolving.
Additionally, there is a unique interplay between vitamin D status, neurocognitive function, mood, and emotions. Its effects on neurotransmitter production, such as serotonin and its role in fighting off oxidative stress and inflammation, all impact both your brain health and the health of your baby's brain in utero and after birth.
Although much of this research is new, promising findings suggest growing importance in the relationship between your vitamin D status and your baby's health, both short-term and long-term.
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