Vitamin D, also known as the sunshine vitamin is one of the essential fat-soluble vitamins. It holds a very high significance in helping the body absorb calcium, which is necessary for promoting the bone health and remodelling of bones. This fat-soluble vitamin exists in two forms which are Vitamin D3 also known as Cholecalciferol, which can be naturally produced in the body and Vitamin D2, commonly known as Ergocalciferol which are consumed through the regular dietary intake.
Sunlight, specially the UVB rays (Ultraviolet- B) are the natural source of Vitamin D. The sunshine vitamin is usually present in human body in biologically inactive form. The sunrays convert the cholesterol present in the body into cholecalciferol. Cholecalciferol is then synthesized in the liver into the metabolite calcifediol which further undergoes hydroxylation in the kidneys to give the biological active form Calcitriol. Calcitriol circulates in the blood in the form of a hormone and plays an essential role in the absorption of calcium.
Functions
Vitamin D which acts both as a nutrient and a hormone is a quintessential element highly significant for a host of bodily functions thanks to its wide range of therapeutic efficacies.
Calcium, being the building block of bones is absorbed by the body due to the presence of Vitamin D which is extremely beneficial in the natural growth and remodelling of bones. It reduces the risk of fracture, strengthen the bones, maintain overall body balance and provides the body with a strong and perfect skeletal structure.
Researches also show the importance of vitamin D in getting strong muscles. A by-product of Vitamin D helps in the contraction and relaxation of muscles. Thus, providing strength and supporting the skeletal frame of the body.
Vitamin D is also essential for the dental health. It prevents tooth decay and loss, strengthen the gums and reduces risk of any oral infection.
Vitamin D, being a fat-soluble vitamin plays a vital role in regulating the renal functions and protecting the kidney from any infections. It plays a major role in cellular growth, repair and metabolism. A sensible exposure to sunlight is very effective in wound healing and repair.
Vitamin D also plays a key role in reducing obesity and maintaining proper weight. The abundance of vitamin D in the body restores the function of the appetite hormone leptin, which gives you a feeling of fullness and reduces the tendency of snacking all the time, thus aiding in weight loss.
Food Sources
Although, you can get a healthy dose of Vitamin D through exposure to sunlight, some people do not get the required amount, due to less sun exposure or other problems. But there is nothing to worry, as Mother Nature has blessed us with a multitude of dietary choices which suffices the Vitamin D requirements of the body.
Some of the food sources which are an excellent source of Vitamin D are:
Vegetables like mushrooms – raw maitake mushrooms, dried shiitake mushrooms, portobello mushrooms, raw white mushrooms
Fortified foods like breakfast cereals, oatmeal, orange juice, soy milk, almond milk, cow’s milk, nuts
Animal sources like egg yolk, cod liver oil, salmon, herring, tuna etc.
Deficiencies
If you shy away from the sunlight or have a very poor intake of Vitamin D, you might be at the risk of Vitamin D deficiency. The sunshine vitamin plays a pivotal role in promoting bone health and maintaining the overall immunity. Lack of Vitamin D may result in various defects starting from low bone density to softening of bones and impaired mineralization of bones.
These deficiencies lead to diseases like:
Rickets:
Rickets characterized by reduced growth and softening of bones. This disease is generally seen in children due to lack of vitamin D. Children develop very thin, deformed bones and a bowed backbone.
Osteomalacia:
Osteomalacia, similar to rickets but is usually seen in elderly people suffering from vitamin D deficiency. This disease reduces the absorption of calcium in the body leading to soft and deformed bone structure, bending of the spinal cord and legs and increased risk of fractures.
Osteoporosis:
Osteoporosis, being most common in elderly where the bone density reduces, making it more porous in nature and causing increased risk of broken bone and fractures.
Apart from this, poor level of Vitamin D in the body may also make you prone to infections, reduce wound healing, cause fatigue and weakness.
Alopecia Areata:
While many factors contribute to hair loss, nutrient deficiency is one of them. A steep decrease in low Vitamin D levels causes Alopecia Areata, an autoimmune disease characterized by severe hair loss. Vitamin D levels have an opposite relationship with non-scarring hair loss which implies that high Vitamin D levels reduce chances of hair loss and vice versa.
Type 2 Diabetes:
Vitamin D plays a large role in improving the body’s sensitivity to insulin, the hormone responsible for regulating blood sugar levels. Insulin resistance is a major cause of type 2 diabetes besides non balanced cholesterol levels and abnormal blood pressure. Preservation of insulin secretion and increasing insulin sensitivity are among many health benefits that Vitamin D offers.
Also Read: Lower Levels Of Vitamin D Can Give Frequent Headaches In Men
Dementia:
Dementia or memory loss impacts thinking patterns that may affect daily life in many ways. Alzheimer’s and Vascular Dementia are quite common forms of memory loss particularly in old age. Compared with people who had normal Vitamin D levels, those with lowered Vitamin D levels have an increased risk of developing dementia even at an early age.
Toxicity
Vitamin D though extremely necessary for healthy bodily functions and maintaining the bone and teeth health, over exposure to sunlight or consuming higher amounts of vitamin D through food sources and supplements might be fatal to the body.
As vitamin D is produced in the body, over exposure to sunlight may result in excessive production of calcitriol which may cause toxicity and remain in the blood for several months. Excessive sun exposure may also cause severe skin damage and may lead to skin cancer.
The sunshine vitamin is extremely beneficial for enhancing the overall immunity of the body and combatting various harmful bacteria and viruses. A good boost of vitamin D supplements or foods rich in it is pivotal for treating upper respiratory tract infections like the common cold, sore throat, cough and flu symptoms.
Scientific researches show that low levels of vitamin D in the body have increased the risk of seasonal affective disorder, or seasonal depression. The low levels of vitamin D often affects the activity of the neurotransmitter serotonin making one anxious, stressed and feeling blue. Hence, vitamin D being an anti-depressant, actively participates in uplifting your mood and reducing chances of depression.
Additionally, recent researches also provide evidence in the effectiveness of vitamin D in reducing hypertension which in turn reduces the risk of heart diseases, cardiac arrest, strokes, heart failure etc. Studies found that new regular intake of vitamin D supplementation in prescribed doses even benefitted people already suffering from hypertension by gradually normalizing the pressure levels.
Researches show that the normal intake of Vitamin D through food sources or supplements is 600 I.U. Anything more that the prescribed amount may lead to hypercalcemia (i.e. elevated levels of calcium in the blood stream) causing several health problems like nausea, vomiting, constipation, kidney problem, bone loss etc.
Hence, it is always advisable to take vitamin D supplements in a healthy prescribed amount or just enjoy the outdoors by taking a walk or participating in an outdoor sport to up your vitamin D level in your body.
Frequently Asked Questions
How does vitamin D support bone health?
Vitamin D helps regulate calcium and phosphorus levels in the body, essential minerals for maintaining bone density and strength. Adequate vitamin D levels are necessary for optimal bone mineralization and reducing the risk of osteoporosis and fractures.
Can vitamin D deficiency contribute to mood disorders like depression?
Some studies suggest a link between vitamin D deficiency and mood disorders like depression, anxiety, and seasonal affective disorder (SAD). Vitamin D receptors are present in areas of the brain involved in mood regulation, and low levels of vitamin D may impact neurotransmitter function and mood stability.
What are the symptoms of vitamin D deficiency?
Symptoms of vitamin D deficiency may include fatigue, muscle weakness, bone pain, frequent infections, mood changes, and impaired wound healing. However, many people with vitamin D deficiency may not experience obvious symptoms, making it essential to monitor vitamin D levels through blood tests.
Can vitamin D supplements interact with medications?
Yes, vitamin D supplements may interact with certain medications, including corticosteroids, weight-loss medications, and medications that affect calcium metabolism. It's essential to consult with a healthcare provider before starting any new supplement regimen, especially if you are taking medications or have underlying health conditions.
Who is at risk of vitamin D deficiency?
Individuals who have limited sun exposure (due to factors like living in northern latitudes, wearing sunscreen, or spending most of their time indoors), older adults, people with darker skin pigmentation, individuals with certain medical conditions (such as malabsorption disorders), and those who follow strict vegan diets may be at increased risk of vitamin D deficiency.
References:
1. Vitamin D: The “sunshine” vitamin - By Rathish Nair and Arun Maseeh
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3356951/
2. Vitamin D - National Institutes Of Health
https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
