3 Sneaky Things That Weaken Your Immune System

Avoid These Sly Saboteurs for Stronger Immune Defense

If you’re concerned about your immune health, you’ve probably heard that lifestyle factors, such as drinking and smoking, weaken your immune system. Nicotine, as well as the other chemicals in cigarettes and vape oils, actually suppress your immune system. And alcohol, which is dehydrating and can cause inflammation, is arguably one of the worst things for immunity.

However, there are a handful of other sneaky things that can weaken your body’s natural defense system. Below are 3 sly saboteurs that are best to avoid, or at the very least curtail, if you want to maintain a strong immune system.

Burning the Candle at Both Ends

Sleep, it’ll make or break your immune system. Research shows that getting consistent quality sleep is imperative for a strong, well-regulated immune response. During deep sleep your body produces more immune cells and antibodies for a robust immune defense. Sleep is also the only time your body releases specialized proteins called cytokines, which are mainly responsible for regulating your immune system.1

On the flipside, not getting enough sleep dysregulates the production of immune cells, antibodies and cytokines – weakening your immune system. Studies indicate that lack of sleep in both the short-term (even just one night) and long-term can compromise your immunity.2

Making sure you receive the recommended 7-9 hours of sleep each night is a great strategy for maintaining a strong and healthy immune system. And, in the case that you’re forced to burn the candle at both ends, you can provide additional immune system support in the form of nutrients and supplements. But nothing beats consistent, quality sleep.

Spending All of Your Time Indoors

As it turns out, your immune system needs a healthy dose of vitamin D regularly, which means spending time outdoors. Sun exposure being the best source of vitamin D, after all.

Years of research shows that vitamin D boosts the immune system and plays a role in regulating both the innate and adaptive immune response. Vitamin D deficiency, on the other hand, has been linked to a weakened immune response, as well as autoimmune disorders.3 Low levels of vitamin D have also been linked to increased levels of anxiety and depression, which can further weaken your immune system.4

In addition to sunlight, inhaling phytoncides (chemicals released by trees and plants) has been shown to bolster your immune system, increasing the number of specialized immune cells involved in the body’s first line of defenses.5 Plus, spending time outdoor green spaces, like forests and parks, has also been shown to reduce stress levels.6 A win-win for your your immune health!

Eating a Diet High Processed Foods

Processed foods (more often than not) contain unhealthy trans fats, added sugar and/or high-fructose corn syrup, artificial sweeteners, refined carbs and a variety additives. All of which makes the junk food we love tasty, convenient and addictive. Unfortunately they may also weaken your immune system.

For starters, if you’re filling up on processed foods full of empty calories, chances are you aren’t getting enough of the right nutrients to support a healthy immune system. Your body’s natural defense system requires an ongoing supply of micronutrients for optimal function, including vitamins A, B6, C, D and E, zinc, magnesium, selenium, iron and folate. And the best source of vitamins and minerals come from the foods you eat.

Gut health also plays an important role in immunity, requiring an ongoing supply of prebiotics in the form of fiber to maintain a healthy balance of good bacteria. However, according to the American Society for Nutrition, only 7 percent of adults in the U.S. are getting the recommended amount of fiber in their diets.

Furthermore, studies show that the additives in processed foods, such as emulsifiers, alter gut bacteria composition (creating an imbalance), harm gut lining (increasing gut permeability) and promote gut inflammation.7 They also contribute to obesity, which has a strong immune-mediated component. Obesity is essential a state of low grade chronic inflammation – which also wreaks havoc on the immune system.8

The Bottom Line

If you want strong immunity, it’s imperative to support the health of your immune system by getting enough sleep, spending time outdoors, managing stress and eating a diet full of nutritious whole foods. In essence, avoiding the things that weaken your immune system.

Postbiotics are also another great way to support gut healthy and strong immune system. IMMUSE™ postbiotic has been shown to provide more comprehensive immune system support at the cellular level for more healthy days year round (when taken regularly).* The cutting-edge postbiotic was also recently named The Ingredient of the Year: Microbiome Modulation at the 2023 NutraIngredients-USA award, which you can read more about by clicking the button below.


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1Asif, N. et al. Human immune system during sleep. Am J Clin Exp Immunol. 2017; 6(6): 92–96.

2Irwin, M. et al. Partial sleep deprivation reduces natural killer cell activity in humans. Psychosom Med. 1994 Nov-Dec;56(6):493-8.

3Martens, P.-J. et al. Vitamin D’s Effect on Immune Function. Nutrients. 2020; 12(5):1248.

4Akpınar, Ş., Karadağ, M.G. Is Vitamin D Important in Anxiety or Depression? What Is the Truth?. Curr Nutr Rep. 2022; 11, 675–681.

5Li Q, Effect of forest bathing trips on human immune function. Environ Health Prev Med. 2010 Jan; 15(1): 9–17.

6Hedblom, M. et al. Reduction of physiological stress by urban green space in a multisensory virtual experiment. Sci Rep. 2019; 9, 10113.

7Aguayo-Patrón S.V. et al., Old Fashioned vs. Ultra-Processed-Based Current Diets: Possible Implication in the Increased Susceptibility to Type 1 Diabetes and Celiac Disease in Childhood. Foods. 2017; 6(11):100.

8Paula Neto, H.A. et al., Effects of Food Additives on Immune Cells As Contributors to Body Weight Gain and Immune-Mediated Metabolic Dysregulation. Front Immunol. 2017; 8: 1478.