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Immune system

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Strengthen your immune system

The immune system can only function correctly and protect you from disease when it gets the right fuel. Just as the rest of the body does, it needs energy, vitamins, and minerals. Like a machine, your immune system needs regular maintenance for optimum performance.

The Immune System

Our immune system consists of various mechanisms that protect the body from disease and other dangers. When it is weakened, it cannot effectively fend off pathogens, toxins, and other foreign bodies. 

The consequences of a weakened immune system include:

  •  higher susceptibility to infections.
  •  Infections may be more severe or difficult to treat
  •  increased risk of other diseases

This is why it is important to maintain a strong immune system. 

What Causes a Weakened Immune System

Along with certain medical conditions that compromise the immune system, a nutritional deficiency can also contribute to reduced immune defense. In order for the immune system to operate at full power, it needs a wide variety of vitamins and minerals, most of which we consume through diet. 

Vitamin D

Vitamin D is one example of a micronutrient that contributes to healthy immune function. This led to researchers questioning whether vitamin D can protect against colds. Studies show that people with a vitamin D deficiency have a higher risk of getting a cold, but those with healthy levels of the vitamin are less frequently and less severely sick.

The challenge with vitamin D: we can only get around 10-20% through diet. The rest is produced by the body in response to UVB rays. Depending on latitude, some areas of the country do not get adequate UVB radiation. In these areas and especially during the winter months, it makes sense to take a vitamin D supplement.  


The mineral zinc is instrumental for immune cell development and according to studies, can help to reduce the duration of a cold. However this is likely only true when you take zinc within the first 24 hours of a cold. Zinc does not seem to be effective in generally preventing colds. Our bodies also need magnesium and selenium for immune cell development and activation.

Iron and Vitamin B12 – not just important for vegans

An iron or B12 deficiency may also lead to a weakened immune system, as both play a role in immune defense. As these nutrients are present in animal products, vegetarians and vegans are more frequently deficient in both iron and B12. 

How Can I Strengthen My Immune System?

To strengthen your immune system, you need to make sure that you are not deficient in any important nutrients. Cerascreen offers tests to check for iron, vitamin D,  or vitamin B12 deficiency, as well as a deficiency of the minerals zinc, magnesium, or selenium. To conduct one of these tests, all you need is a small amount of blood drawn from a finger prick, which you then send to our diagnostic laboratory.  

After the lab analysis, you will receive a detailed results report which tells you your level of the measured nutrient. The report also includes recommendations for achieving a level in the normal range. This will allow you to correct a possible deficiency with dietary changes or supplementation, thereby contributing to a strengthened immune system. 



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