Vitamin D3 1000iu - 500 Softgels

Vitamin D3 1000iu - 500 Softgels

  • $25.99

1,000 IU  Softgels

Vitamin D is the sunshine vitamin, which the body creates when skin is exposed to ultraviolet light. It is essential for immune function, calcium absorption, building and maintaining strong bones and teeth, and overall health. Many individuals lack sufficient vitamin D, and vitamin D supplementation is widely recommended throughout life.

Uses & Benefits

  • Supports healthy immune system function
  • Aids in the normal development and maintenance of bones and teeth
  • Helps reduce the risk of developing osteoporosis when combined with adequate calcium, a healthy diet, and regular exercise

Vitamin D3 from Natural Factors provides a convenient daily dose of vitamin D as cholecalciferol to help support immune function and for the development and maintenance of strong bones and teeth. Vitamin D3 is the natural form of this vital nutrient and is most effective at raising blood levels of active vitamin D. 

Vitamin D plays a key role in the absorption of calcium and phosphorus, two minerals that are vital for proper bone mineralization and turnover. Vitamin D is also required for the body’s innate and adaptive immune responses.

Each tablet or softgel delivers a single 1000 IU (25 mcg) dose of vitamin D3 for convenient maintenance of adequate vitamin D levels, even when dietary intake and sun exposure are lacking. When combined with an adequate calcium intake, a healthy diet, and regular exercise, vitamin D3 helps reduce the risk of developing the brittle, weak bones of osteoporosis.

Vitamin D3 1000 IU is certified non-GMO. This formula contains no artificial colours, preservatives, sweeteners, or common allergens, and is suitable for use during pregnancy and while nursing an infant.


Each Softgel Contains:
Vitamin D3 (Cholecalciferol) .................. 25 mcg (1,000 IU)

Non-medicinal Ingredients: Softgel (gelatin, glycerin, purified water), organic flaxseed oil.


How it works

Vitamin D3 is a fat-soluble vitamin made naturally in skin exposed to the sun’s ultraviolet rays. The liver then converts this form of vitamin D3 (called calciol) into calcidiol (25-hydroxyvitamin D3), the inactive storage form of vitamin D3. Calcidiol is then converted into the active form of vitamin D3 called calcitriol (1,25-dihydroxy-vitamin D3), primarily in the kidneys, through the action of the 1α-hydroxylase enzyme. The kidneys are not the only place in the body where this conversion happens, however; 1α-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 and lymphocytes (Hansdottir & Monik, 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 inflammation (NIH, 2016). Vitamin D3 helps increase the number of receptors on immune system cells, may influence the release of protective proteins when there is an infection, and helps white blood cells recognize foreign invaders.

Vitamin D promotes calcium and phosphorus absorption, which is necessary to build and maintain bones and teeth; enables dietary calcium absorption from the intestines and resorption of calcium from the glomerular filtrate; and facilitates calcium incorporation in bone for proper bone mineralization (Murray, 1996).



Vitamin D plays a key role in the body’s innate immunity and natural antimicrobial defence system. It is an important nutrient for endurance athletes because of their susceptibility to upper respiratory tract infections (URTIs) caused by the immune suppression that follows long and intense periods of physical activity. A clinical study found that endurance athletes who were deficient in vitamin D (blood concentrations <30 nmol/L) had a 40% greater frequency of URTIs than those with optimal levels (blood concentrations >120 nmol/L). URTI symptoms were also observed to last an average of eight days longer in athletes who were deficient in vitamin D compared to those with optimal levels (He et al., 2013).

In a meta-analysis of 25 randomized, double-blind, placebo-controlled trials, adults who took vitamin D supplements had a significantly reduced incidence of acute respiratory tract infection compared to those who did not receive vitamin D (Martineau et al., 2017). Interestingly, vitamin D appears to help the body modulate immune response, preventing an over-reaction known as a cytokine storm, while still supporting the body’s efforts to fight off infection (Hansdottir et al., 2010).

Vitamin D supports the absorption and use of calcium and phosphorus to help increase bone mineralization. These nutrients work synergistically to sustain peak bone mass and prevent bone loss with age. A 10-year study of 9,382 men and women over the age of 25 found a significant relationship between bone mineral density and supplementation with vitamin D and calcium. At doses greater than 400 IU of vitamin D per day, participants were shown to have significantly stronger hip bones (Zhou et al., 2013). Hip fractures in postmenopausal women and older men are common signs of weakened bones from low bone mineral density. A placebo-controlled clinical trial found that postmenopausal women who supplemented their diets for five years with 1000 mg of calcium and 400 IU of vitamin D per day experienced a 0.62 hazard
ratio for hip fracture (Prentice et al., 2013).

Osteoporosis is the outcome of thin and weakened bones and is a significant health concern for aging women. Fortunately, it can be prevented by maintaining bone mineral density through diet and exercise. In a clinical study, participants were supplemented with a daily dose of 2000 IU of vitamin D, 100 mcg of vitamin K2, and 25 mg of magnesium. After 12 months, bone mineral density in the hip, spine, and femoral neck of participants had increased by 4%, 8%, and 4%, respectively (Genuis et al., 2012).