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Finding the best vitamin D supplement for the immune system


Active vitamin D in the body is referred to as 1, 25 dihydroxyvitamin D3. A vitamin is something we cannot make ourselves and is essential for normal bodily function. Vitamin D3 can be obtained from the diet (cod-liver oil or fatty fish are rich in vitamin D3), or it can be synthesised in the skin with sun exposure (the sunshine vitamin); therefore, it does not entirely meet the standard definition.

Vitamin D3 is essential for normal phosphorus and calcium absorption and cell division. It also helps maintain normal blood levels of calcium, and normal teeth, muscle and bone health. However, here we discuss the importance of vitamin D for normal immune function. Vitamin D deficiency or low vitamin D levels are common in the UK due to high latitude and the prevalence of indoor lifestyles, so we explore the potential benefits of supplementation. You will also learn the proper way to take a vitamin D supplement and how to choose the best vitamins for your immune system.

What role does vitamin D play in immunity?

There are two forms of dietary vitamin D; vitamin D2 can be found in fungi and yeasts, while vitamin D3 can only be found naturally in animal products. Vitamin D2 is less potent than vitamin D3. Even dietary vitamin D3 is not biologically active. Interestingly, immune cells can actually activate vitamin D3, while this same vitamin may regulate immune cell activity.

Research has discovered that many immune cells involved in the innate and adaptive immune response have vitamin D receptors. This indicates that vitamin D plays a role in regulating the immune system. In fact, vitamin D has been shown to inhibit T Helper cells but activate T Regulatory cells. Switching off the immune response is essential to avoid an over-active immune system.

Vitamin D foods on a table from above

Do vitamin D supplements help the immune system?

Vitamin D deficient individuals or people with low vitamin D levels might benefit from supplementation – consult your healthcare provider to check for a deficiency. Diet and lifestyle can lead to vitamin D insufficiency. The following individuals may have low vitamin D:

  • Those living in the northern hemisphere. Short winter days mean less sun exposure for vitamin D3 synthesis in the skin. According to Public Health England, residents should take a daily vitamin D supplement in the winter, from November until March.
  • Individuals with high melanin concentration in the skin Melanin protects the skin from UV damage which can also reduce vitamin D formation.
  • Individuals with a limiting diet. Vegan diets will lack natural sources of vitamin D3 because it is found in animal products. Diets lacking in healthy fat sources (including fatty fish) may also not contain enough vitamin D.

Vitamin supplements can also be a convenient way to boost nutrient intake. Sometimes it can be challenging to ensure you get the proper nutrients through diet, so a vitamin D supplement can help support the immune system's normal function.

Woman on a laptop while drinking an orange drink

Taking a vitamin D supplement

It would help to consider the proper way to take a vitamin D supplement for the best results. The three things to bear in mind are form, dosage and combinations.

What is the difference between vitamin D and vitamin D3?

Vitamin D is a blanket term; the vitamin can be found naturally in different forms. Vitamin D2 is found in plants, including yeasts, mushrooms, and other fungi. Vitamin D3 is a more potent form of vitamin and is only found in animal products. Vitamin D3-rich foods include cod liver oil or fatty fish. A vitamin D3 supplement raises vitamin levels much more effectively, and this effect also lasts longer than with vitamin D2.

How much vitamin D should you take per day?

From a young age, we must take at least ten micrograms of vitamin D daily. We should not consume more than 100 micrograms of vitamin D daily as this can lead to an accumulation of calcium in the blood (hypercalcaemia) which can damage healthy bone.

When should you take vitamin D?

Vitamin D3 can be taken at any time of the day, but since it is a fat-soluble vitamin, it is best taken with or after a meal containing a source of dietary fat. Examples of dietary fat sources include butter, avocado, nuts, olive oil or cheese.

Choosing the best vitamin D supplement for the immune system

Selecting the right form of vitamin D is only the first step to finding the best vitamin D supplement for the immune system. Here, we discuss what else to look for in an immunity supplement.

Zest Active product image with orange (fruit) illustration and background graphic

Firstly choose an immunity supplement containing the Recommended Daily Allowance of vitamin D3; also, look for other immune support vitamins such as vitamin C, zinc, vitamins B6, B12, folate, selenium and copper. Combining vitamins into one supplement makes supporting immune health easy and convenient. Our immune supplement contains eight immune-boosting vitamins.

Next, consider the formula of your supplement. Vitamin D tablets can be convenient, but contain small doses, fillers, binders and casings. Alternatively, powdered supplements are designed for optimal nutrient delivery and are free from fillers and binders.

Zest Active has been scientifically formulated to support immune health, cognitive function, muscle function and normal energy levels. The supplement is portioned into daily powdered sachets to be added to water, smoothies or juices; it's also sugar and caffeine free.

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