Luke Stanaway

Registered Nutritionist

Enhance Your Life With Vitamin D: The Benefits Of Supplementation 

Enhance Your Life With Vitamin D: The Benefits Of Supplementation 

Enhance Your Life With Vitamin D: The Benefits Of Supplementation 

Key Takeways

  • Calcium and phosphorus absorption and retention are aided by vitamin D, which are important components in bone formation.

  • Vitamin D may help to prevent cancer cell proliferation, fight infections, and reduce inflammation.

  • Adequate vitamin D levels can reduce the risk of infection and even lessen the severity of some illnesses.

  • Low vitamin D levels may play a role in the onset of multiple sclerosis (MS).

  • Vitamin D supplementation lowers the risk of acute respiratory infections (ARIs), particularly in people who are vitamin D deficient.

  • Taking vitamin D supplements, or vitamin D supplements combined with marine omega-3 fatty acids, reduces the occurrence of autoimmune diseases like rheumatoid arthritis and autoimmune thyroid diseases.

  • Those with low vitamin D levels are more likely to develop dementia than those with adequate levels.

  • Adults should consume at least 600 IU (15mcg) of vitamin D per day, while children, pregnant women, and those at risk of insufficiency should consume at least 400 IU (10mcg) per day.

What is Vitamin D? 

Vitamin D is both a dietary nutrient and a hormone that our bodies produce. This fat-soluble vitamin is well-known for facilitating calcium and phosphorus absorption and retention, both of which are important components in bone formation. Furthermore, laboratory research has revealed that vitamin D may inhibit cancer cell proliferation, manage infections, and reduce inflammation. The presence of vitamin D receptors in multiple organs and tissues suggests that this vitamin may have important functions other than bone health, which scientists are currently investigating. 


Vitamin D vs. D3  

There are two types of vitamin D supplements: vitamin D2 (also known as "ergocalciferol" or pre-vitamin D) and vitamin D3 (also called "cholecalciferol"). Both D2 and D3 are naturally occurring forms that result from sun exposure. While D2 is produced by plants and fungi, D3 is produced by animals, including humans. Because vitamin D3 is the most active form of vitamin D, most vitamin D pills are labelled as D3. This form of vitamin D is also easier for the body to absorb, which means it can deliver more health advantages.   


Vitamin D sources 

Although some foods are fortified with vitamin D, the nutrient occurs naturally in only a small number of foods. As a result, most people find it difficult to get enough vitamin D from their diet alone, and supplementation through tablet or liquid forms is frequently required. Although the skin is the primary natural source of vitamin D, it can be insufficient for many people, particularly those who live in areas where sunlight is scarce during the winter or who have little sun exposure due to prolonged indoor activity. Furthermore, those with darker skin have lower vitamin D blood levels because the pigment (melanin) acts as a filter, reducing vitamin D synthesis. It is also important to note that receiving the sun's rays in a sunny office or driving in a car will not help you obtain vitamin D because window glass completely blocks UVB ultraviolet light.  

Vitamin D-rich foods include

  • Fatty fish such as salmon, sword fish, tuna fish 

  • Egg yolk 

  • Fortified dairy products, cereals or orange juices 

  • Beef liver 

  • Cod liver oil 


Vitamin D benefits 

Although observational studies have found a strong correlation between lower rates of specific illnesses and areas with more sunlight or higher serum levels of vitamin D, clinical trials that use vitamin D supplements to treat a specific disease continue to yield inconclusive results. These inconsistencies may be explained by different study designs, varying vitamin D absorption rates in different populations, and different doses administered to participants.  

Vitamin D for Longevity 

Researchers believe there is a link between Vitamin D and longevity because there has been a statistically significant reduction in all cause mortality or premature death in people with higher levels of Vitamin D. One study of nearly 60,000 people discovered a 7% reduction in all-cause mortality and, in particular, a reduction in cancer risk, which was thought to be largely responsible for the 7% mortality reduction. Lower Vitamin D levels were associated with a 25% increased risk of premature death from cardiovascular disease, cancer, and respiratory diseases in a study of 250,000 people. 

Vitamin D for the immune system 

Vitamin D is required for the immune system to function properly. It aids in the regulation of white blood cell synthesis, which is important for combating bacteria and viruses. Adequate vitamin D levels can help minimise the risk of infection and may even lessen the severity of certain illnesses. 

Multiple Sclerosis 

According to current research, low vitamin D levels may be a factor in the development of multiple sclerosis (MS), and correcting this deficiency could potentially prevent up to 40% of cases. This claim is supported by recent research indicating that people who have genetic markers for low vitamin D levels are more likely to develop MS. 

Common Flu and Infections 

While randomised controlled trials investigating the potential of vitamin D to prevent acute respiratory infections (ARIs) have yielded conflicting results, a comprehensive meta-analysis of individual participant data has shown that daily or weekly vitamin D supplementation reduces the risk of ARIs. This effect is especially noticeable in people who are severely deficient in vitamin D. 

Other Autoimmune 

A large randomised double-blind placebo-controlled study that followed over 25,000 people aged 50 and up, discovered that taking vitamin D supplements (2,000 IU/day) or vitamin D supplements in combination with marine omega-3 fatty acids (1,000 mg/day) for five years reduced the occurrence of autoimmune diseases by approximately 22% when compared to a placebo. The autoimmune disorders observed in the study included rheumatoid arthritis, psoriasis, polymyalgia rheumatica, and autoimmune thyroid diseases such as Hashimoto's thyroiditis and Graves' disease. These supplement dosages are widely available and well tolerated in the general population. 

Cognitive Decline 

Using Mendelian randomisation to examine over 427,000 White European participants, researchers discovered that those with low levels of vitamin D in their blood (25 nmol/L) had a 54% higher risk of developing dementia than those with sufficient levels of 50 nmol/L. 


Recommended daily Vitamin D intake 

Vitamin D intake recommendations vary depending on age and other factors. Adults should consume at least 600 IU (15mcg) of Vitamin D per day, while children, pregnant women, and those at risk of insufficiency should consume at least 400 IU (10mcg) per day. 

To delve a bit deeper, we find that the recommended daily intake of vitamin D and the optimal serum levels required to prevent illness are still debated scientifically. In November 2010, the Institute of Medicine (IOM) issued recommendations recommending that children and adults in the United States and Canada consume 600 IU of vitamin D per day despite the fact that organisations such as The Endocrine Society recommend 1,500 to 2,000 IU of vitamin D per day to achieve adequate serum levels. Controversially, the IOM believed there was insufficient evidence to link vitamin D consumption to health benefits other than bone health. While additional research has since confirmed the benefits of getting enough vitamin D, there is still no consensus on what constitutes an adequate amount. 

It is crucial to remember that the recommended daily consumption may be lower for persons who are more vulnerable to toxicity, such as those using certain medications or suffering from specific illnesses. It's usually a good idea to consult with a doctor or a nutritionist before beginning to use supplements. 

Can you have too much Vitamin D? 

The most common cause of Vitamin D toxicity is the use of supplements. Toxicity from low levels of Vitamin D found in food is unlikely, and excessive sun exposure does not cause toxicity because excess heat prevents D3 formation. To prevent toxicity, it is advised to avoid daily Vitamin D supplements containing more than 4,000 IU unless under the supervision of a doctor. 

Toxicity symptoms may include

  • Appetite loss Weight reduction 

  • Heart rate fluctuation 

  • Hardening of blood vessels and tissues as a result of high calcium levels in the blood, which could harm the heart and kidneys. 

Recommended Vitamin D 3 supplements 

When selecting a Vitamin D 3 supplement, search for one that has been third-party tested and is free of impurities. It is also critical to look for a vitamin D product that contains the recommended daily amount. Among our suggestions are: 

  • BePure

  • Garden Life 

  • Nodric Naturals 


Vitamin D is an important mineral for overall health and wellbeing. Unfortunately, many people are vitamin D deficient, which can lead to a variety of health problems. Vitamin D supplementation can assist in improving overall health and immunity, as well as lower the risk of certain diseases. It is critical to ensure that you are getting enough Vitamin D from your food or, if necessary, from a supplement. Before beginning any supplement program, consult with a doctor or nutritionist to ensure that it is safe and appropriate for you. 

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