Vitamin D is best known for its role in bone health as it helps with improved absorption of calcium and phosphorus. But what is lesser known is that vitamin D benefits your health in many other powerful ways. Emerging research is consistently highlighting how vitamin D could be incredibly important in improving various aspects of our health – from regulating immunity, lowering inflammation, improving gut health and lowering risk of auto-immune disorders.
Despite its diverse role and multiple health benefits, it is termed as the most common nutritional deficiency by the Centers for Disease Control and Prevention. So, what can vitamin D deficiency do to your health?
Low levels of vitamin D can cause soft bones, a condition called rickets in children and osteomalacia in adults. This can lead to muscle weakness, bone pain and weak bones that are prone to fractures. While this has been fairly well known for some time, new research suggests that even moderately low levels of vitamin D can manifest in a number of other conditions not related to your bone health such as allergies, asthma, autoimmune disease, metabolic syndrome, poor immunity and heart disease. Vitamin D deficiency is even known to affect your sleep cycle, brain functions and gut health, according to some studies.
Clearly, a long-term deficiency can cause serious damage to your health. It is important you understand the symptoms that indicate you might be deficient. This is a problem that could be easily fixed with simple vitamin D supplements in the first place, before the situation gives rise to other more serious problems.
Signs of Vitamin D deficiency
1. Widespread body pain and fatigue
One of the most perceptible signs of vitamin D deficiency is having multiple points of aches and pains in the body. Many studies have linked low levels of vitamin D with chronic widespread pain and fatigue.   You should your vitamin D levels checked, if you have the following symptoms:
- General, non-specific pain and tenderness in the body
- Achy joints; Pain in lower back, ribs, hips, pelvis and legs
- Excessive fatigue and weakness; feeling tired for no reason
- Muscle pain and weakness
- Excessive muscle soreness after exercise (that takes long time to go)
- Stress fractures
Studies show that vitamin D supplements:
- May help improve symptoms in people with chronic widespread musculoskeletal pain. 
- Can be a very useful strategy in managing pain in a lot of conditions including fibromyalgia, chronic back pain, menstrual cramps and arthritis, when combined with good quality sleep. 
- Suppress the production of proteins that promote inflammation in the body, which helps in managing how the body responds to pain.
Lack of vitamin D may be the reason you are often becoming sick. This is hardly surprising as the sunshine vitamin is known to play a big role in regulating your immune system.
One important way it regulates your immune functions is by stimulating the production of proteins that work as natural antibiotics in the body. There is also evidence that T cells of the immune system need vitamin D for the chemical transformation needed to become active and kill invading pathogens.
Several emerging studies show that vitamin D supplementation may:
- Lower the risk of seasonal influenza A in children during the winter season 
- Protect against respiratory infections, that may worsen asthma symptoms. A study showed that this protective effect was more pronounced for people with severely low levels of vitamin D. Supplementation also worked best when it was given daily instead of weekly. 
- Reduce frequency and severity of asthma attacks, when given along with conventional treatment 
Low levels of vitamin D have been linked to poor sleep quality. But can you get more sleep time by improving your vitamin D status? Well, studies suggest it does help.  
The precise mechanism of how vitamin D may be affecting your sleep is not clear yet. Chronic pain in muscle and bone due to vitamin D deficiency can result in loss of sleep and fatigue. Since vitamin D may have an important role in lowering pain and inflammation, this could be reason that vitamin D helps you sleep better. In addition, researchers have found that we have vitamin D receptors in parts of the brain that regulate sleep.
4. Gut problems
If you are feeling bloated or suffering from constipation, this could be a sign that your vitamin D levels are low. Research suggests more than 50% of people with irritable bowel syndrome (IBS) don’t have sufficient levels of vitamin D.
It is not clear what comes first, IBS or vitamin D deficiency. But most experts agree that it might work both ways. People with long-term IBS have absorption issues, leading to nutritional deficiencies (including Vitamin D, B12, magnesium and iron). At the same time, long-term vitamin D deficiency also makes you prone to auto-immune disorders, including IBS.
There is good evidence to believe that increasing levels of vitamin D in the body help improve gut health, reduce IBS symptoms, reduce risk of relapse and improve quality of life in people with IBS.   .
One possible explanation is that vitamin D regulates gut inflammation and immunity. Since low-grade mucosal inflammation and activation of immune functions are involved in the development of IBS, vitamin D levels may help. Vitamin D also helps to restore good bacteria in the gut and reduce the levels of disease causing bacteria, which may explain its beneficial effect on gut health.
Other sneaky signs that you may be deficient in vitamin D
- Depression and irritability
- Excessive head sweating
- Wounds that don’t heal easily
- Hair loss
- Erectile dysfunction
- High blood pressure
- Inadequate sun exposure
- Increased use of sunscreen
- Issues with vitamin D absorption (people with celiac and Crohn's disease may have trouble absorbing enough vitamin D from the intestines).
- Chronic liver and kidney problems. (Your liver and kidneys have enzymes that convert vitamin D which you get from sunshine or supplements to its biologically active form).
- People who are obese and overweight
- People with darker skin
- People living in a northern latitude (further from the equator)
Did you know the reason your body may not be able to use the vitamin D (from what your body makes or gets through supplements) is because of a lack of magnesium? Magnesium plays many incredible functions in the body – including DNA synthesis, energy production, regulating calcium levels, regulating blood pressure, maintaining heart functions and even in controlling stress levels. And of all these functions, magnesium also helps in several activities related to how your body makes and uses vitamin D.
- Magnesium works as a co-factor for enzymes that metabolize vitamin D
- Magnesium converts vitamin D into its bio-active form (calcitriol) in the bloodstream.
It is important to understand that you need magnesium to use vitamin D correctly in the body. So, your magnesium deficiency is working two ways when you are given high doses of vitamin D supplements. One, you are not able to utilize vitamin D.
Two, it is making you even more deficient in magnesium. This causes symptoms that resonate with signs of vitamin D deficiency, leading your doctor to prescribe higher doses of the vitamin to alleviate your symptoms.
When it comes to vitamin D, it is important that you not only take magnesium but also vitamin K2 for best results. This is yet another example of how you can’t rely on just one nutrient to correct a health problem. Nutrients work in a synergistic fashion with one complementing another’s function.
Role of vitamin K2 in vitamin D’s function
When it comes to your bone and heart health, taking vitamin D alone is not enough. While we have already seen how magnesium is a great accompaniment to calcium and vitamin D, the equation is still incomplete without vitamin K2. It has got to do with how K2 regulates calcium levels in the body.
Vitamin K2 activates two proteins:
- Osteocalcin that promotes calcium assimilation in your bones.
- Matrix GLA protein that prevents calcium from getting into soft tissues such as blood vessels.
The good news?
While vitamin D deficiency may be on the rise, fixing the problem is relatively straight-forward and inexpensive. Sensible sun exposure (always wear a hat) and taking vitamin D supplements is a safe and effective strategy to up your levels. As for how much to take, it’s always a good idea to check with your doctor.
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