Most people think about sun exposure, but there is so much more we can learn about Vitamin D to help support our health journey. This post is all about the science of Vitamin D and how important it is to our bone health, immune system, and everything in-between. Let's dive in.
Vitamin D is a Hormone
You might not think of a Vitamin D supplement as hormone replacement therapy, but scientists suggest1 that Vitamin D may be the most important hormone you have. Much of today's research indicates that the substance is a hormone, not a nutrient. This is because the body synthesizes Vitamin D after sun exposure, activating it in the kidneys and liver, using it to regulate your calcium metabolism.
Our bodies create about 90% of the Vitamin D it needs when exposed to direct UV light. The remaining 10% of Vitamin D intake comes from foods rich in the substance. If you're unable to get much sunlight exposure, then you would benefit from taking a Vitamin D supplement.
Experts estimate that sensible sun exposure on bare skin for up to ten minutes a day, three times a week, could allow the body to produce enough Vitamin D2. However, since the substance only has a half-life of around two weeks, it's possible for your stores to begin depleting quickly, particularly during winter months.
If you're like most people, you might feel a little more sluggish during winter if you're not getting access to the sun or the Vitamin D your body needs.
Could You Have a Vitamin D Deficiency?
If your body doesn't obtain enough Vitamin D to ensure optimal health, this is known as a Vitamin D deficiency. The most certain way to determine if you are deficient is through a blood test.
Vitamin D deficiencies are more common in individuals who experience the following:
- Dark skin
- Age of 50+
- Gastrointestinal issues
- Bone discomfort
The Benefits of Vitamin D
Over the years, scientists have conducted a significant amount of research regarding the benefits of the hormone "Vitamin D." We've discovered that low levels of this hormone could lead to diabetes, dementia, heart disease2, cancer, and even an increased risk of Alzheimer's.
The link between Vitamin D and healthy, strong bones was made quite some time ago after doctors came to realize that sunlight could help to prevent rickets in children. Today, many experts consider Vitamin D to be an essential hormone to good health - important for far more than just the health of your bones. In fact, recent research has begun to show that Vitamin D could be crucial to preventing a range of health problems. For instance:
- Research estimates that up to 75% of cancers3 could be prevented by adequate levels of Vitamin D.
- Vitamin D controls phosphate and calcium levels in the blood, ensuring good bone strength and growth.
- Vitamin D is crucial to the creation of "t-cells", the immune system cells responsible for protecting your body against disease and bacteria.
- A Vitamin D deficiency can contribute to inflammatory diseases.
- Children taking 1,200 IU of Vitamin D per day can reduce their risk of influenza by up to 40%4.
Vitamin D is a hormone with several important functions, ranging all the way from the absorption of calcium, to regulating the immune system. Let's break down more specific areas where Vitamin D has a strong impact.
Vitamin D for Healthy Bones
Vitamin D is crucial for the regulation and maintenance of both phosphorus and calcium levels in the body. Both factors are essential for maintaining healthy bone function. We need Vitamin D to absorb the calcium in our intestines and re-claim calcium that might otherwise be excreted in the kidneys.
In children, a Vitamin D deficiency can cause rickets, a disease regularly characterized by impaired mineralization, brittle bones, and bow-leggedness. In adults, a Vitamin D deficiency frequently manifests as osteoporosis or osteomalacia. Osteoporosis is the most common, while osteomalacia results in muscular weakness, poor bone density, and can even lead to small fractures in the spine.
Vitamin D for Immune Function
More often than not, my clients are deficient in Vitamin D, which means you might be too! One study found5 that insufficient levels of Vitamin D can be found in 57% of US adults. Additional studies estimate that one billion people around the world have a Vitamin D deficiency.
Vitamin D works as a sort of switch in your body, turning off, or on various processes and genes that your body needs to maintain good health. Active Vitamin D can be distributed around many areas of the body, including the intestines, bones, colon, brain, and immune cells, which all feature their own Vitamin D receptors.
Sufficient levels of Vitamin D will strengthen the immune system, and reduce your risk of sickness and disease. Vitamin D can initiate the peptides in your immune system that trigger a powerful antimicrobial response, allowing you to fight off any foreign invaders before they become a complete infection.
Vitamin D and Autoimmune Diseases
Autoimmune diseases are what most of my clients are working through on their health journey. Many of these diseases take place when your immune system is stressed or overly confused, and begins to attack your own tissues, rather than dealing with external pathogens. Vitamin D can prevent the cultivation of autoimmune disease by promoting T cells responsible for accurately differentiating between "self" cells, and outside invaders. When active Vitamin D promotes T cells, it makes your immune system smarter and teaches it how to prevent autoimmune disease.
Although research is ongoing in this area, various studies already demonstrate higher levels of autoimmune disease in people with a Vitamin D deficiency.
Vitamin D and Infant Health
Children with normal levels of blood pressure were given 2,000 IU per day of Vitamin D6 in one study and found to have less stiffness in their arterial wall following 16 weeks of treatment when compared to participants given 400 IU per day. This indicates that Vitamin D could play a role in infant heart health.
In the past, a lack of Vitamin D has been associated with a range of health conditions for children, including a higher risk of atopic and allergic diseases, including eczema7, asthma, and dermatitis. It's possible that Vitamin D could improve the anti-inflammatory effects of substances called "glucocorticoids," which means that the hormone might be effective at supporting people with asthmatic conditions resistant to steroids.
Vitamin D and Cancer Prevention
There is a great deal of exciting research into the link between Vitamin D and cancer today. Vitamin D is known for being important for regulating cell-to-cell communication and cell growth. Certain studies have indicated that the active form of Vitamin D, "calcitriol", could reduce the progression of cancer growth8 by slowing the development of blood vessels within the cancerous tissue. This process would increase cell death in cancerous substances, and reduce metastases.
Vitamin D influences more than 200 different genes within the human body, which can be impaired in people with deficiencies. Vitamin D has also been associated with a range of other health conditions too, including hypertension, cardiovascular disease, rheumatoid arthritis, swine flu, autism, Alzheimer's disease, and so much more. Ultimately, Vitamin D could be the most important hormone in the body for health purposes. However, more research is required before we can say for sure.
Vitamin D and Seasonal Affective Disorder (SAD)
Estimates indicate that up to 20% of Americans9 may suffer from Seasonal Affective Disorder each winter. "SAD" causes fatigue, depression, and other significant mental concerns when sunlight grows scarce. Where Seasonal Affective Disorder differs from standard depression, is that many people experience a full remission during the summer and spring months. Often, Vitamin D is associated with SAD, as well as more chronic forms of depression and mental illness.
One clinical trial10 found that supplementation with high doses of Vitamin D can help to reduce the symptoms of depression significantly. It's easy to understand the link that could exist between Vitamin D and seasonal affective disorder when you know that vitamin D receptors are present in a wide range of brain tissues. Activated Vitamin D receptors can improve nerve growth in the brain, making the hormone essential to all-around mental health and enhanced cognitive function.
Getting Your Recommended Intake of Vitamin D
Just like any hormone, the studies that have been conducted regarding Vitamin D have shown that this substance is crucial to good health. Typically, Vitamin D intake is measured in two different ways "micrograms" and international units. One microgram of Vitamin D can measure into 40 IU of Vitamin D. Though required amounts of Vitamin D will depend on the unique circumstances of the person in question, the US Institutes of Medicine11 currently set the recommended daily intake levels at:
- 0-12 months (infants) - 400 IU
- 1-18 years (children) - 600 IU
- 19-70 years (adults) - 600 IU
- 70+ years (seniors) - 800 IU
- Lactating or Pregnant women - 600 IU
The goal of preventing a Vitamin D deficiency is to ensure that individuals are able to reach and maintain the right level of this crucial hormone within their body. Usually, doctors and health experts recommend a variety of ways in which people can increase their hormone levels, including:
Consuming more foods that contain Vitamin D
There are very few food sources that contain natural Vitamin D. This means that it can be difficult for anyone to achieve their recommended daily amount through diet alone. In some cases, foods can be "fortified" with Vitamin D, which means that supplemental levels of the hormone are added. Some foods that contain Vitamin D include:
Getting enough sun exposure
The exact amount of sun exposure required for optimal Vitamin D levels is not certain. Around five to ten minutes of sun exposure, two or three times a week is often recommended to help you absorb the right amount of Vitamin D into your body. However, people who are older, those with a darker skin color, or individuals who live in cloudier climates might require more sun exposure.
When improving your sun exposure levels, remember that standing behind a window and using sunscreen can limit your ability to absorb Vitamin D. However, it's important to keep in mind that too much sun exposure can also heighten your risk of skin cancer and premature aging.
Taking Vitamin D supplements
Finally, some people will need to take Vitamin D supplements to help them fight back against deficiency. We offer many different options for Vitamin D supplements on Shop Vibrant Life, shop now and see what we have to offer. It's important to discuss how much Vitamin D you're taking with your doctor - particularly if you're taking more than the amounts listed in the recommended daily allowance.
Too much Vitamin D can be problematic in some cases. Additional magnesium will be needed to convert Vitamin D into its active form.
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