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The best vitamin C supplement for the immune system


Ascorbic acid, more commonly referred to as vitamin C is an essential vitamin we must obtain from our diet. This vitamin can be found in plant-based foods; some vitamin C foods include citrus fruits and peppers. Vitamin C is an essential nutrient because it is a co-factor for many vital processes in the body. Some processes that vitamin C is necessary for include collagen synthesis, the normal function of blood vessels, the nervous and immune systems.

We will discuss the effect of vitamin C on the immune system and its involvement on a biological level. Then we explore the possible benefits of a vitamin C supplement and the proper way to take a supplement containing vitamin C. Finally, we help you understand what to look for in a supplement for immune support to ensure you choose the best one.

How does vitamin C affect the immune system?

Vitamin C is a co-factor for fifteen different enzymes; this means that fifteen processes would be disturbed without vitamin C. Vitamin C is also an electron donor and protect cells from oxidative stress. This ability to donate electrons allows vitamin C to neutralise free radicals that would otherwise ‘steal’ electrons from cellular or extracellular components – thus damaging their structure. Vitamin C can also regenerate vitamin E.

Oranges hanging from a tree

Vitamin C is vital for healthy immune function; it supports both the innate and adaptive immune response. Ascorbic acid is essential for a healthy skin barrier function and helps an immune cells function properly. Finally, vitamin C supports white blood cell function, maturation, and proliferation.

It is well known that a severe vitamin C deficiency has been associated with immune function impairments. However, here we discuss the possible health benefits of vitamin C supplementation and the potential immune-boosting capabilities of vitamin C for non-deficient individuals.

The benefits of a vitamin C supplement

Obtaining all the required vitamins and minerals from a healthy, balanced diet is possible. However, a supplement can bring peace of mind. With supplementation, you can be confident that you are taking in enough vitamin C for normal immune function daily; this can be difficult to determine with dietary vitamin C intake. Supplements can bring many other benefits, including convenience, effective nutrient delivery and ingredient combinations for optimal health.

The recommended daily allowance for vitamin C is 40mg for adults (NHS England). However, certain groups may benefit from higher doses of daily vitamin C to boost their immune systems, particularly athletes.

Exercise in sedentary individuals benefits immune health; however, highly active individuals can experience immune suppression for several hours after strenuous exercise. Higher doses of vitamin C (200mg above the Recommended Daily Allowance) can help maintain the normal functioning of the immune system during/after intense physical exercise. A dietary supplement can boost your vitamin C intake and help support the immune system and body function daily.

Man and woman running

Taking a vitamin C supplement

When starting a new vitamin supplement, you must consider necessity and safety. You may not require a supplement if you have adequate vitamin C levels or your diet contains vitamin C rich foods daily; specific limiting diets may lack vitamin C.

Vitamin C supplements are generally safe to use, with minimal side effects. However, carefully consider the dosage that you need. 40mg is the Recommended Daily Allowance of vitamin C; athletes may want to consume 240mg for immune-boosting benefits. However, there is no need to be consuming more than this amount daily. If you are consuming over 2,000mg per day can lead to side effects, including:

  • Nausea, vomiting and diarrhoea.
  • Stomach cramps and bloating
  • Heartburn
  • Headaches
  • Fatigue, sleepiness, or insomnia
  • Skin flushes

Vitamin C supplements are also generally safe to consume with or without food, and you may want to consider ingredient combinations to boost the absorbance and function of vitamin C. Some ingredients to combine with vitamin C are iron (aids the absorbance of vitamin C) and marine collagen peptides. Vitamin C helps build the collagen proteins found in your hair, skin, bones, teeth and gums.

Choosing a vitamin supplement for the immune system

You need to take advantage of multiple immune-supporting ingredients to get the most out of your vitamin supplement. Our top choices for immune-boosting ingredients (in addition to vitamin C) are:

Choosing a multivitamin supplement is ideal for overall immune health and convenience. Our scientifically formulated supplement contains eight ingredients for immune support, including Vit C, vitamin B12 and B6, vitamin D and Zinc. Zest Active also contains amino acids.

Zest active support banner with Eilish McColgan to the right

Our powdered sachets are designed for convenience and efficient nutrient delivery. Moreover, Zest Active supplements support energy-yielding metabolism, muscle function and cognitive function; you can gain many benefits from our supplement range. Our supplements are always free from fillers, binders, casings and stimulants; we also use naturally derived sweeteners and avoid added sugar.

Shop Zest Active today and start building your immune and overall health

Frequently asked questions

When is the best time to take vitamin C?

Vitamin C supplements can be taken at any time of the day. High or multiple doses of vitamin C are best spread over the day for better absorption.

What is the best form of vitamin C?

The most common form of vitamin C for supplements is pure ascorbic acid. However, some supplements contain Calcium Ascorbate or Ester C. These are non-acidic forms of vitamin C that break down into Ascorbic acid (vitamin C) in the body. The primary difference is taste; ascorbic acid may add acidity to your supplement. Stabilised forms of vitamin C tend to be used in topical skin treatments.

Is 1000mg of vitamin C too much?

1000mg of vitamin C is significantly over the Recommended Daily Allowance of vitamin C for men and women and is generally not required for optimal immune health. However, doses under 2000mg daily are unlikely to have unpleasant side effects. Higher dosages of vitamin C should generally be avoided.

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