Vitamins are micronutrients that the body cannot produce, so they must come from our diet or supplements. There are many different types of vitamins, all with their specific roles in the body, but this article will focus on the role of vitamin D!
Fat soluble vitamin
Vitamin D is a fat-soluble vitamin, meaning it is best absorbed with dietary fat and then stored in the body’s fatty tissues and liver. Because fat-soluble vitamins can be stored unlike water-soluble vitamins, they last longer in the body.
Basic roles of vitamin D in the body
Vitamin D has many roles in the body, it is essential for bone health, helps with calcium and phosphorus homeostasis and contributes to immune function.
Bone health
Vitamin D plays a key role in bone health through its effect on calcium absorption. Vitamin D enhances calcium absorption in the small intestine, which increases calcium available for storage in bone. Low vitamin D can lead to decreased calcium absorption, causing the bones to release calcium into the bloodstream. This process of releasing calcium from the bones can cause weakened bones and an increased risk of fracture leading to the development of osteomalacia and osteoporosis.
Osteomalacia: Osteomalacia is a ‘softening of the bones’ disease usually due to vitamin D deficiency, which can cause calcium loss in the bones
Osteoporosis: Osteoporosis is a bone disease that develops when bone density and bone mass decrease. This can affect the strength of the bones leading to more fractures.
Immune Function
Vitamin D is a unique nutrient as it is also considered a hormone. It circulates in the blood and binds to receptors to trigger a specific action in the body. Many studies over the years have shown that vitamin D has a key role in immune function.
Vitamin D receptors are found in almost all cells and tissues of the body. Vitamin D promotes immune health by binding to receptors on immune cells. Once vitamin D binds to these cells, they are stimulated to produce products that can defend the body against foreign pathogens such as bacteria and viruses!
Studies have also shown that vitamin D helps with inflammation. When the body has a foreign pathogen, such as a bacteria, the immune system releases proteins to fight it and this can cause hyperinflammation, vitamin D has been shown to suppress inflammation.
The research looked at the role vitamin D plays in respiratory infections. The results showed that vitamin D supplementation may help reduce the risk of acute respiratory infections.
Not enough vitamin D
As vitamin D does not occur naturally in many foods, we must rely on fortified foods, sun exposure and consider supplementation to ensure adequate amounts.
Common symptoms of low vitamin D:
More prone to disease
There are a few reasons why someone may have low vitamin D levels, including:
Inadequate dietary intake or insufficient sun exposure
The body does not absorb the vitamin properly (medical conditions)
Medical conditions that affect vitamin D levels
Kidney and liver disease: The kidneys and liver contain enzymes that convert the vitamin D in our blood into the active form (the vitamin D our bodies can use). If these organs are not working properly and there is an insufficient amount of these enzymes, this can cause low levels of active vitamin D in the body.
Crohn’s disease: is an inflammatory bowel disease that affects the gastrointestinal (GI) tract. Vitamin D levels may be low in patients due to insufficient sun exposure, poor absorption and reduced conversion of the active form of vitamin D
Cystic fibrosis: cystic fibrosis patients do not absorb fat-soluble vitamins properly, so even with vitamin D intake the body may have difficulty absorbing and using it
Celiac disease: when someone with celiac disease consumes gluten it damages their intestinal cells, untreated it can cause malabsorption of nutrients such as vitamin D
Vitamin D can be obtained from diet, sun exposure and supplements.
Diet
There are few foods that naturally contain vitamin D, but the best sources include fatty fish such as salmon, mackerel and tuna. Foods such as egg yolk, beef liver, mushrooms and cheese also contain some vitamin D. Another way to get vitamin D through the diet is with fortified foods, such as:
Milk and fortified drinks of plant origin
Enriched yogurt and margarine
As many foods do not contain vitamin D, it is difficult to meet the requirements of this vitamin from food alone. It is also important to get exposure to sunlight to ensure adequate amounts.
exposure to the sun
When your skin is exposed to sunlight, it is able to produce vitamin D. Cholesterol in your skin absorbs ultraviolet B (UVB) rays from the sun and converts it into provitamin D, which is then converted into the active form of the vitamin D. Different factors can affect the amount of vitamin D our skin can make from the sun, including season, time of day, location on the equator, and even skin color. Staying indoors, wearing clothing, and using SPF can all block UVB rays and therefore reduce or eliminate vitamin D synthesis from the sun.
Time of day
Studies have shown that the best time for sun exposure for vitamin D is midday during the summer season. At midday UVB rays are strong which means you need less time in the sun to get adequate amounts of vitamin D.
Time
People who live farther from the equator have trouble making vitamin D from the sun, UVB rays are absorbed by the ozone layer, so it takes more time in the sun for the skin to absorb enough rays to make vitamin D. During During the winter months, people living in these areas are not able to produce much vitamin D from the sun, as the UVB rays are not strong enough.
Skin color
A person’s skin color is determined by a pigment called melanin. Someone with a darker skin color usually has more melanin than someone with a lighter skin color. Melanin in the skin absorbs UVB rays to help protect against sunburn and skin cancers. Someone with darker skin may need to spend more time in sunlight to absorb more UVB rays for vitamin D synthesis.
It is important to apply sun protection to reduce the risk of skin damage and even skin cancer. It should not rely on sun exposure to get enough vitamin D!
Both UVA and UVB rays from the sun can cause long-term skin damage, cataracts, and even skin cancer! The best way to reduce your risk of these adverse health effects is to practice sun protection and protect yourself from the sun.
Wear sunscreen (broad spectrum, at least SPF 30 or higher) daily even on cloudy days
Wear clothing that blocks the sun, including a wide-brimmed hat that covers your neck, ears, eyes, and scalp.
Supplements
Vitamin supplements
Studies have shown that vitamin D is a common micronutrient that people around the world don’t get enough of. The Reasons include limited foods containing vitamin D, insufficient sun exposure throughout the year, as well as other factors such as age and health status. Supplementing with vitamin D can be an easy way to increase your vitamin D intake and reduce your risk of deficiency.
Make an appointment with one of our dietitians today to discuss your vitamin D intake, whether a supplement is right for you and how much you should be taking!
