Vitamin D the sunshine vitamin is among the most deficient substances in the body. How can something that is made naturally by the body be lacking and what happens to your body when you don’t have enough? I find my hair is not as strong and my joints feel a little rickety. To make the body feel whole and healthy every bit of its function needs to be considered.
Vitamin D is not a vitamin it is a hormone that is made within the body. Its discovery began with a boom in rickets amongst children during the Industrial Revolution. With a movement from farm life to smoggy city factory life exposure to sunlight decreased drastically.
In 1822 a Polish physician noted that children working in factories in Warsaw and or living in the smog-filled city had drastically increased cases of rickets over children who lived and worked in the countryside, his recommendation was to increase exposure to sunlight. Though it is more prevalent today, vitamin d deficiency has been around for thousands of years, it is hypothesized that Neanderthals exhibited bone deformations that can be attributed to rickets.
Main Functions of Vitamin D
- Calcium and Phosphorous: metabolism and normal calcification of bones.
- Vitamin D role in Calcium Metabolism: increases absorption in the gut, decreases excretion from kidneys, respiration of calcium
- Supports Healthy Bone and Teeth: puts calcium-phosphorus into teeth and bones
- Immunity: prevents rickets, cancer-fighting, fights of free radicals that are persistent in the system
- Mental Health: provide proper nutritional support for the nervous system
Vitamin D2 and Vitamin D3 are absorbed though into the intestinal lining after ingestion. From there they first arrive at the liver where they are metabolized into 25-hydroxyvitamin D [25(OH)D] also called calcidiol. Then in the kidneys, it is converted into 1,25 dihydroxyvitamin D [1,25 (OH)2 D] also called calcitriol. These actions are conducted by the presence of the enzyme 1 a-hydroxylase. The benefits of Vitamin D are then displayed on the body by entering circulation and travels to the main areas of calcium tissue uptake; small intestine and bones. the small intestine has vitamin d receptors for D3, these activated receptors allow for the absorption of calcium through the intestines. The benefits of Vitamin D are further expressed in the body via the endocrine and autocrine actions of calcitriol by its activation of Vitamin D on cell receptors.
“More than three fourths of all Americans are vitamin d-deficient.”
―John Cannell,Athlete’s Edge: Faster, Quicker, Stronger with Vitamin D
If there is not enough calcium in the blood, parathyroid hormone and calcitriol will move to bones and signal the release of calcium from bones as a way to maintain intracellular and extracellular calcium concentrations. When there is sufficient calcium in the diet and body, calcitriol along with parathyroid hormone will be regulated and calcitriol production and activity is low. When calcium is lacking in the body its production is high. When the body is deficient in Vitamin D, calcium and phosphorus are also released from the bones to enter the kidney to bring up serum levels. This makes the assessment of serum levels of calcium and phosphorus a flawed way to assess Vitamin D status.
A decrease in Vitamin D and an oversaturation of calcium can often result in calcification to the breast, to arterial plaque as well as other areas in the body as calcium cannot be properly utilized and metabolized by the body. Moreover, if there is too much Vitamin D in the system due to toxicity, calcification within the body can also occur. Therefore it is essential to be testing once a year for serum Vitamin D levels especially if one is on a vitamin d supplements. Calcium ion serum testing should also be conducted once a year to monitor the amounts that are in the body and if there is a possibility of an overdose of vitamin d (too much vitamin D can lead to bone calcification).
Common Reasons for Vitamin D Deficiency
Adults and the elderly are among the most at-risk individuals of a Vitamin D deficiency. The percentage of individuals who are deficient ranges between 25–60% and is dependant on the age group and the geographic location. The further you live from the equator the more Vitamin D you will need to supplement with, particularly during the fall, winter and spring months. Often the recommended dosages are far to low from what the body actually requires to function optimally.
- people with darker skin. The darker your skin the more sun you need to get the same amount of vitamin D as a fair-skinned person.
- People who spend a lot of time indoors during the day. For example: If you’re housebound, work nights or are in the hospital for a long time
- People who cover their skin all of the time. For example: If you wear sunscreen or if your skin is covered with clothes.
- People that live farther from the Equator. This is because there are fewer hours of overhead sunlight the further you are from the equator.
- Older people have thinner skin than younger people and this may mean that they can’t produce as much vitamin D.
Most living things require water, food, oxygen and sunlight for a healthy existence. Why would this not apply to humans?
– Carlos A. Camargo
- Infants that are breastfed and aren’t given a vitamin d supplement. If you’re feeding your baby on breast milk alone, and you don’t give your baby a vitamin d supplement or take a supplement yourself your baby is more likely to be deficient in vitamin D.
- People who are overweight (obese) — Fat-soluble Vitamin D gets trapped in fat tissue
- Living in big cities where the buildings block sunlight
- If one’s kidney and liver are not functioning to par Vitamin D cannot be properly processed and activated therefore resulting in a deficiency in Vitamin D stores. Moreover, such a decline in this hormone can also lead to further issue to the organs.
- Individuals who take hormone lowering medication can result in a decrease and deficiency in Vitamin D.
Signs of Vitamin D Deficiency
There are many reasons why we may become deficient in Vitamin D but what exactly are Vitamin D deficiency symptoms.
- Rickets in children and the elderly (bow legs, knock-knees)
- Osteomalacia in adults
- Muscle cramping, constipation, nervousness
- Poor bone development
- Colon Cancer and other Cancers
- Heart Disease
- High Blood Pressure
- Autoimmune Diseases (such as osteoporosis)
- Chronic Fatigue
- Psoriasis or eczema
- Infections that are recurrent
- Infertility — particularly in males
Source of Vitamin D
When we think of vitamin d we may consider the sun or fortified foods (which are fortified with Vitamin D2) and beverages. However, when food is produced as it should, there is a great deal of natural vitamin D found within it. We are so lucky to have a combination of both Vitamin D2 and Vitamin D3 in our diet and available for our body to create. Below are a few Vitamin D foods.
Vitamin D3: Is found in animals sources and by-products
Vitamin D2: Is found in plant leaves — though in very low amount, moreover as it is in the form of Vitamin D2 it is hard for the body to utilize it and convert it. If an individual is Vegan or Vegetarian it is incredibly important to make sure they supplement with Vitamin D.
- Cod Liver Oil
- Raw Milk
- Eggs (Yolk)
- Beef Liver
Signs of Vitamin D Toxicity
Vitamin D toxicity should not be based on elevated 25(OH) D levels instead it should be based on symptoms and clinical syndrome of hypervitaminosis D and hypercalcemia. Some symptoms of Vitamin D toxicity includes;
- excessive thirst
Vitamin D2 and Vitamin D3
There are two forms of Vitamin D supplements. Vitamin D3 also known as cholecalciferol, is synthesized by UV radiation of 7-dehydrocholesterol to previtamin D3. Vitamin D2 also known as ergocalciferol is sourced from UV irradiation of ergosterol found in plants but largely in fungi. Both of them are available to us through the consumption of food (Vit D2 & Vit D3) or produced by our skin (Vit D3). The active form of this prohormone is calcitriol or 1,25-dihydroxyvitamin which we measure through serum levels in the body. Although both forms of Vitamin D supplements turn into calcitriol, it is when cholecalciferol is supplemented that the concentration of 25(OH)D is profoundly raised. Though both will positively increase calcitriol levels in the body, Vitamin D3 has a longer half-life then Vitamin D2, which will require more frequent dosages to bring up the elevation to levels that are sufficient to the body.
Supplementing with Vitamin D
Maintenance levels during times of the years when daylight is at its lowest should be between 2,000–4,000 IU per day. D2 (ergocalciferol) and D3 (cholecalciferol) can both be found at supplements, however, in order to obtain the benefits from calcitriol, it is essential to obtain Vitamin D3.
If one is very low in Vitamin D it is essential to increase supplementation, for some time, to 10,000 IU daily. Liquid Vitamin D3 supplementation is best and easiest to take. Make sure to check levels for each new season so as to know when to supplement and when to wain off and enjoy the sun.
When supplementing with Vitamin D3 it is beneficial to take the supplement with a meal that contains a good amount of fat as the vitamin is fat soluble. Taking it along with fat will allow for enzymes to be present in the digestive tract to properly ensure the uptake of the nutrient.
Recommended Vitamin D Supplements
Garden of Life — Vitamin D3 -Vegan
- My Kind Whole Food Organics
- great for those on the go as it is a vanilla flavoured spray
- One spray is equivalent to 1000 IU
- Vegan, Organic, Non-GMO, Soy-free and Gluten free
- Contains no synthetic binders or fillers
D Drops — Baby D Drops
- Contains 90 drops (400 IU per drop)
- Can be given to infants 1 drop daily
- Easily applied and given front the fingertip or the nipple to a breastfed baby.
- Wheat, gluten, soy, corn, sugar, milk, peanut free, palm oil free
- Great brand for children, they also have a 600 IU dosage that can be great for older children. For young adults and adults, I would recommend a different brand if you are doing maintenance, as even the 365 drop 1000 IU per drop bottle gets used up quickly (though they do carry a 2000 IU per drop bottle).
Nordic Naturals — Vitamin D3 Vegan
- Sourced from lichen
- GMO-free, soy free
- 60 servings, 1000 IU per serving
- Liquid dropper, can add into smoothies that contain a bit of fat for better absorption.
Nordic Naturals — Vitamin D3 gel caps 120
- fish oil is sustainably harvested
- easy absorption
- 1 caps = 1000 IU
- Can take more at the same time or spread it out with your meals. I would not recommend taking this supplement on an empty stomach.
Remember to begin with a lower dosage and work your way up. If you are low in Vitamin D, make sure you have also checked the functioning of your liver and kidneys to make sure that they can properly convert vitamin D into its active form of calcitriol in the body. Otherwise, you are going to be paying a whole lot of money for something that won’t be working effectively.
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