Immune system booster

Being sick is probably one of the things most people hate. Whether it's a pesky cold or the flu, most would give anything to prevent getting sick. With that in mind, it's no wonder that there is no shortage of supplements that promise to keep users from getting sick. Sadly, not all of these products deliver on their promises.

Strengthening the immune system

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

But if you're a serious athlete who trains hard, you've probably experienced firsthand that repeated strenuous and/or prolonged training can increase your risk for infections. Sports scientists have recognized that too much strenuous and demanding training can suppress the immune system (1). Competitive athletes and even average fitness enthusiasts know that few things 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 about which supplements are best to boost the immune system comes up quite often. Immune system function can be measured in different ways, and beyond that there are the 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, it can be difficult to directly compare studies because of these different ways used to measure immune function. Regardless, there are a number of foods, vitamins, plant extracts and supplements that have been scientifically proven to have the ability to promote immune system function.

Foods that strengthen the immune system

When it comes to foods, there are few that have been truly 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 lot 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 supplementation with 5 to 10 grams of spirulina per day can help improve immune system function, antioxidant levels, and exercise performance (2-4).

Vitamins strengthening the immune system

Probably the most commonly used vitamin to strengthen the immune system is vitamin C. However, even though there are a plethora of studies that have examined 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 research examining the factors that determine the effectiveness of vitamin C supplementation suggests that dose and age of the individual may be important factors, with dosages above 2 grams being much more effective and children responding better to vitamin C than adults. Despite all the controversy, vitamin C supplementation has been shown to be very safe, so the benefits outweigh any potential drawbacks.

Quercetin and the immune function

Another substance that is supported by a great deal of credible science and could be more broadly classified 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, in addition, has benefits in terms of performance, body composition, and antioxidant response to athletic training (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 strengthening the immune system

If you ask the average person which plant extract they would associate with improving the immune system, you will almost always get Echinacea as the answer. This is because Echinacea is the plant that has been studied the most, and the best, in terms of 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 a common cold (10). Some of this confusion may be explained, at least in part, by the extreme range of types and strengths of echinacea extracts that have been investigated in different studies. Some more recent studies conducted with highly standardized and high-quality echinacea extracts show without a doubt that echinacea does indeed strengthen immune system function (11, 12).

Supplements strengthening the immune system

Many sports supplements claim to boost immune system function. One of the few such 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, since colostrum is actually supposed to be broken down into its components in the digestive tract like all other proteins.

However, colostrum is known to have high levels 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 have 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 used as much as 20 to 60 grams (14). At such dosages, daily supplementation with cholostrum becomes very expensive.

Conclusion

In summary, staying healthy and free of infections is something that is highly valued by any athlete regardless of whether they are a professional athlete or a recreational athlete. There are a variety of supplements that promise to improve the function of the immune system and make it more resistant to infections. 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 like sleep, stress management, and nutrition.

Particularly for competitive athletes and others who train intensively, the intense training often performed on a daily basis can compromise immune system function, increasing the risk of infection. For this group of people, certain supplements, foods and vitamins can offer significant benefits when it comes to staying healthy. Using common sense, one will realize that a balanced approach that includes lifestyle, exercise and supplementation is the best way to stay healthy.

References:

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