Imagine if everything harmful at some immediate and noticeable effect. For example, if we went several days without exercising our hair turned blue, or maybe, after a fourth glazed doughnut, our forehead turned purple. In a world like that, we would more likely to develop good habits and stick with them. Unfortunately, in the real world, many harmful practices can become habits long before we realize their impact and recognize that they’re bad for us.
The three habits that are the topic of today’s post are ones that are not traditionally linked to the immune system. Not many people would connect inflammatory foods, excessive worry, and a sedentary lifestyle to weakened immunity. Nonetheless, these three common practices can become habits that wreck our immune system.
Inflammatory Foods and Immunity
In recent years there has been much talk about the dangers of chronic inflammation. Although inflammation is a standard way in which the body defends itself, chronic inflammation occurs when the body’s inflammation button gets stuck in the “ON” position. Certain triggers, such as allergy-causing foods or disease-causing germs, can create a consistent state of chronic inflammation. Research now links chronic inflammation with obesity, heart disease, diabetes, and even cancer. 
We now know that most foods can be grouped into one of two categories – inflammatory foods and anti-inflammatory foods. Inflammatory foods tend to promote chronic inflammation while anti-inflammatory foods tend to lower or prevent chronic inflammation. Highly refined carbohydrates such as wheat flour and sugar, as well as, processed oils are among the most inflammatory foods in our diets. Studies show that these foods, which are linked to rapid weight gain, also undermine our immune systems.
Too many refined carbohydrates, unhealthy fats, and other highly processed foods; we can create a situation where the internal chemicals that regulate the immune system are thrown out of balance. Worse still, by frequently choosing these inflammatory foods over healthy anti-inflammatory foods like fruits, vegetables, and omega-3 fats; we deprive the immune system of important vitamins, minerals, and antioxidants. 
Excessive Worrying and Immunity
These days there tends to be an endless stream of things we can worry about. But, did you know that simply worrying about an unpleasant outcome can be a source of stress? Constant worry can be a source of anxiety which triggers a cascade of stress-related chemicals. Under natural circumstances, our bodies quickly relax, and our stress chemicals return to normal. However, when we consistently hold worrisome thoughts, we can trigger ongoing stress responses. 
When our bodies are flooded with stress hormones, the immune system has a hard time doing its job. Long periods of elevated stress chemicals can begin to weaken the immune system. According to the American Psychological Association, such high levels of consistent stress suppresses immune function.  This highlights the importance of good stress management practices such as regular exercise. 
Sedentary Living and Immunity
A sedentary lifestyle is one characterized by much sitting and little physical exercise. According to a 2016 study published in the Journal of the American Medical Association more than 65 percent of Americans are not getting the recommended 150 hours of exercise per week. Moreover, the average amount of daily sedentary time has risen to 6.2 hours.
Since consistent and moderate exercise is one of the best ways to strengthen the immune system, this is bad news. While researchers aren’t exactly sure how exercise and immunity work together, they do have several theories. The theories include how exercising helps white blood cells (immune system cells) move faster through your bloodstream, and how physical activity can decrease stress hormones, which are damaging to the immune system. 
The Bottom Line
A well-balanced diet, effective stress management, and exercise are three of the best things we can do to support a healthy immune system. By contrast, consuming large quantities of inflammatory foods, devoting excessive time to worrying, and getting stuck sedentary lifestyle dramatically undermines our immune system which leads us susceptible to disease.
What Do You Think?
Have you seen either of these 3 challenges lead to sickness?
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 Journal of Sport and Health Science Volume 8, Issue 3, May 2019, Pages 201-217 (https://www.sciencedirect.com/science/article/pii/S2095254618301005)