INGREDIENTS
Each Softgel Contains:
Vitamin D3 (Cholecalciferol) ..................ย 2500 IU (62.5 mcg)
Non-medicinal Ingredients:ย Softgel (gelatin, glycerin, purified water), organic flaxseed oil.
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HOW IT WORKS
Vitamin D3 is a fat-soluble vitamin made naturally in skin exposed to the sunโs ultraviolet rays. The liver converts this form of vitamin D3 (called calciol) into calcidiol (25-hydroxyvitamin D3), the inactive storage form of vitamin D3.ย Calcidiol is then converted into the active form of vitamin D3 called calcitriol (1,25-dihydroxyvitamin D3), primarilyย in the kidneys, through the action of the 1ฮฑ-hydroxylase enzyme. The kidneys are not the only place in the bodyย where this conversion happens, however; 1ฮฑ-hydroxylase is also present in parts of the respiratory system, including the airway epithelium and alveolar macrophages, as well as in immune system cells called dendritic cells andย lymphocytes (Hansdottir & Monick, 2011).
Vitamin D activates T cells, the killer cells of the immune system (von Essen et al., 2010), and is involved in regulating cell growth, neuromuscular and immune function, and infl ammation (NIH, 2021). Vitamin D3 helps increaseย the number of receptors on immune system cells, may infl uence the release of protective proteins when thereย is an infection, and helps white blood cells recognize foreign invaders.
Vitamin D also promotes calcium and phosphorus absorption, which is necessary to build and maintain bones andย teeth; enable dietary calcium absorption from the intestines and resorption of calcium by the kidneys; and facilitateย calcium incorporation in bone for proper bone mineralization (Stargrove et al., 2008; Margulies et al., 2015).
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RESEARCH
Vitamin D supports the absorption and use of calcium and phosphorusย to help increase bone mineralization. These nutrients work synergistically to sustain peak bone mass and prevent bone loss with age.ย A 10-year study of 9,382 men and women found a significant relationship between bone mineral density and supplementation withย vitamin D and calcium. Over time, women ages 25 and older who tookย more than 400 IU vitamin D per day were found to have greater boneย mineral density in their lumbar spine, hips, and femoral neck bones.ย Men ages 16โ24 with a daily vitamin D intake above 400 IU wereย found to have greater bone mineral density in their hip and femoralย neck bones (Zhou et al., 2013). In people who have experienced hipย fractures, vitamin D deficiency can slow recovery. Patients with serumย levels below 12 ng/mL were found to have more difficulty regainingย their ability to walk after surgery (Hao et al., 2020).
Osteoporosis is the outcome of thin and weakened bones and isย a significant health concern for aging women. Fortunately, it can beย prevented by maintaining bone mineral density through diet andย exercise. In a clinical study, participants were supplemented withย a daily dose of 2000 IU of vitamin D, 100 mcg of vitamin K2, andย 25 mg of magnesium. After 12 months, bone mineral density in the hip,ย spine, and femoral neck of participants had increased by 4%, 8%,ย and 4%, respectively (Genuis & Bouchard, 2012).
Vitamin D plays a key role in the bodyโs innate immunity and naturalย antimicrobial defense system. It is an important nutrient for endurance athletes because of their susceptibility to upper respiratory tractย infections (URTIs) caused by the immune suppression that follows longย and intense periods of physical activity. A clinical study found that endurance athletes who were deficient in vitamin D (blood concentrationsย <30 nmol/L) had a 40% greater frequency of URTIs than those withย optimal levels (blood concentrations >120 nmol/L). URTI symptomsย were also observed to last an average of eight days longer in athletesย who were deficient in vitamin D compared to those with optimal levelsย (He et al., 2013).
In some populations, a moderately higher dose of vitamin D is neededย to have a measurable effect on blood levels and health outcomes.ย In a randomized, controlled intervention, women who supplementedย with 2000 IU of vitamin D3 per day during their second and thirdย trimesters of pregnancy were found to have 36% higher levels of theย immune systemโs T cells than women who supplemented with 400 IUย per day (Zerofsky et al., 2016).
Health surveys show that more than 27% of Canadians ages 3โ79ย years have inadequate vitamin D levels, putting them at an increasedย risk for osteomalacia, osteoporosis, bone loss, and fractures, alongย with URTIs and some chronic health problems (Statistics Canada,ย 2019; Lips et al., 2019; He et al., 2013). Certain populations have an increased risk of vitamin D deficiency, including people with limited UVBย exposure from living at northern latitudes or regularly wearing sunscreen and protective clothing, people over 70 years of age, and thoseย with a limited intake of foods containing vitamin D, such as oily fish,ย dairy products, and other fortified foods (Lips et al., 2019). Additionally,ย malabsorption syndromes, such as inflammatory bowel disease andย celiac disease, are associated with a higher incidence of vitamin Dย deficiency than in healthy populations (Margulies et al., 2015).