Immune system booster

Being sick is probably one of the things that most people hate. Whether it's a pesky cold or the flu, most would give anything to avoid getting sick. With this in mind, it's no wonder that there is no shortage of supplements that promise to protect the user from getting sick. Sadly, not all of these products deliver what they promise.

Strengthening the immune system

When it comes to boosting the immune system, there are many common sense approaches that most people will be aware of. These include getting enough sleep, avoiding excessive stress, exercising regularly and eating a balanced diet.

However, if you are a serious athlete who trains hard, then you will probably have experienced first-hand that repetitive strenuous and/or prolonged exercise can increase the risk of infection. Sports scientists have recognized that too much strenuous and demanding exercise can suppress the immune system (1). Competitive athletes and even average fitness enthusiasts know that there are few things that can hinder the achievement of fitness goals more than injury or illness. Staying healthy allows for periodized training that ultimately results in improvements in strength and athletic performance. For this reason, athletes and trainers are always eager to develop new strategies to reduce the risk of infection and other illnesses.

The best supplements to strengthen the immune system

The question of which supplements are best suited to strengthen the immune system comes up quite often. The function of the immune system can be measured in different ways and there are also different parts of the immune system called innate immunity and acquired immunity. When it comes to testing the effects of different supplements on immune function, these different ways of measuring immune function can make it difficult to directly compare studies. Regardless, there are a number of foods, vitamins, plant extracts and supplements that have been scientifically proven to boost immune system function.

Foods that boost the immune system

When it comes to foods, there are only a few that have been scientifically proven to have a positive effect on the immune system. Some popular examples would be yogurt and chicken broth. One popular superfood really worth mentioning is spirulina. Spirulina is known for its high content and wide range of micronutrients and there are a number of scientific studies that have looked at the effects of spirulina on different areas of health. When it comes to the immune system, several studies have shown that supplementing with 5 to 10 grams of spirulina per day can help improve immune system function, antioxidant levels and exercise performance (2-4).

Vitamins that boost the immune system

Probably the most common vitamin used to boost the immune system is vitamin C. However, even though there are tons of studies that have investigated the effects of vitamin C on the common cold, there is still no conclusive answer to the question of whether vitamin C can actually prevent a cold or whether it can reduce the duration and severity of a cold (5). Previous studies that have examined the factors that determine the effectiveness of vitamin C supplementation suggest that the dose and age of the individual may be important factors, with doses above 2 grams being much more effective and children responding better than adults to vitamin C. Despite all the controversy, vitamin C supplementation has been shown to be very safe, so the benefits outweigh any possible disadvantages.

Quercetin and immune function

Another substance that is supported by a great deal of credible science and could be classified more broadly as a vitamin is the flavonoid quercetin. Quercetin is the most abundant flavonoid found in fruits and vegetables. There have been a number of recent studies that have shown that quercetin can not only significantly improve immune function in athletes, but also has benefits in terms of performance, body composition and antioxidant response to exercise (6, 7). Vitamin C and quercetin act synergistically together and it has been shown that this combination has benefits that go beyond the combination of the individual effects of the two substances (8, 9).

Plant extracts that strengthen the immune system

If you ask the average person which plant extract they would associate with improving the immune system, the answer will almost always be echinacea. This is because echinacea is the plant that has been studied the most for its ability to boost the immune system. However, even after all this research, there is still no real consensus among scientists as to whether echinacea can really reduce the frequency of occurrence, symptoms or duration of the common cold (10). Part of this confusion may be at least partially explained by the extreme range of types and strengths of echinacea extracts that have been investigated in different studies. Some more recent studies using highly standardized and high quality echinacea extracts show without a doubt that echinacea does indeed boost immune system function (11, 12).

Supplements that boost the immune system

Many sports supplements claim to boost the function of the immune system. One of the few of these supplements whose effects are supported by solid science is colostrum. Studies, with subjects ranging from endurance athletes to strength athletes, have shown that colostrum supplements can help reduce the incidence of common infections such as upper respiratory tract infections (13). Colostrum is basically a protein, which is why scientists have had a hard time explaining exactly how it works, as colostrum is supposed to be broken down into its components in the digestive tract like all other proteins.

However, colostrum is known to have a high content of bioactive compounds and scientists now believe that some of these compounds escape digestion and therefore remain biologically active even after consumption (13). The only downside to colostrum is that it is not cheap and in addition to this, most studies show that you need to use larger amounts to see an effect. The lowest dosage used in one study that showed a positive effect on performance and immune function was 10 grams (14). Most other studies have even used between 20 and 60 grams (14). At such dosages, daily supplementation with cholostrum becomes very expensive.

Conclusion

To summarize, staying healthy and infection free is something that is highly valued by any athlete regardless of whether they are a professional or recreational athlete. There are a variety of supplements that promise to improve the function of the immune system and improve resistance to infection. Unfortunately, it is all too easy to waste money unnecessarily on immune system supplements that are not scientifically proven to work, especially if you don't pay attention to the basics such as sleep, stress management and nutrition.

Particularly in the case of competitive athletes and other athletes who train intensively, the intensive training that is often carried out on a daily basis can impair the function of the immune system and thus increase the risk of infections. For these individuals, certain supplements, foods and vitamins can offer significant benefits when it comes to staying healthy. If you use common sense, you will realize that a balanced approach that includes lifestyle, exercise and supplementation is the best way to stay healthy.

References:

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