- The immune system is a complex network of cells and proteins that defends the body against infection.
- Demonstrating whether an herb — or any substance, for that matter — can enhance immunity is, as yet, a highly complicated matter.
- Regular exercise which is light to moderate in intensity can strengthen the immune system.
Your immune system plays a critical role in living a long and healthy life.
What Does Immunity Mean?
Immunity is how well you can fight off a particular virus, infection, or disease.
There are two types of immunity: 1) Innate and 2) Acquired.
Innate immunity is what you are born with, while acquired immunity is developed during your life as you are exposed to new environments and experiences.
What is the Immune System?
Your immune system is your body’s defense against infection and disease. It is made up of 5 main components:
- white blood cells
- the complement system
- the lymphatic system
- bone marrow
What Causes a Weak Immune System?
There are many different factors that affect a weakened immune system.
Genetics and epigenetics play a role as many people are born with immunocompromising conditions.
Your age is another factor in immunity. As you age, your immune system is weakened. This is because less B and T cells are being produced. The functioning of mature lymphocytes also decreases.
Nutrient deficiencies play a role in immune system regulation, too. While the research in this area is not extensive, we know that particular vitamin and mineral deficiencies can result in weakened immunity.
In addition, the foods we eat affect our immune systems. A typical Western diet is high in inflammatory foods, such as processed and packaged meals, fast food, trans and saturated fats, and sugar.
Here’s why you want to avoid the following foods in excess to support a healthy, strong immune system:
1. Sugary sweets like baked goods, candy, etc.
Research in the 70s discovered that after you consume sugar, your immune response is lowered for a couple of hours.
You can imagine what this would mean if you consume sugar at breakfast, lunch, dinner, and between meals. Newer research found that while this may not be the case for viral infections, it remains particularly true for bacterial infections.
2. Alcoholic beverages
It also damages epithelial cells, T cells, and neutrophils which are all critical for immunity. Once the gut microbiota is altered, the liver’s immune system is activated and an inflammatory response occurs.
Both chronic drinking, and acute binge drinking, have negative consequences on your immune system.
3. Fried foods
Many fried foods, like French fries and donuts, contain acrylamide which is produced in the process of frying carbohydrates. Acrylamide is a carcinogen that has been associated with the development of autoimmune disorders and cancers.
4. Processed and packaged foods
A typical Western diet is filled with processed and packaged foods. Studies show that the high intakes of sugar, salt, and fat that are often found in these foods negatively impact your immune system.
5. Refined oils
Consuming refined oils can increase free radicals in your body. These increase oxidative stress and damage cell membranes, DNA, and lipids. If you’re going to use oil, choose a cold-pressed oil like avocado or extra virgin olive oil which are still intact with their fatty acids and vitamin E properties.
6. Red meat
In 2015 the WHO classified red meat as a probable carcinogen.
A sugar found in red meat, pork, and lamb, known as N-glycolylneuraminic acid (NeuG5c), has been found to increase systemic inflammation. Over a long period of time this can result in higher levels of cancers.
Cows’ milk has several components that can harm our immune system.
Beta casein has been shown to increase an immune response, inflammation and have negative gastrointestinal effects.
The NeuG5c sugar found in meats is also found in milk products.
Switching to non-dairy milk, like oat or almond milk, is an easy alternative that is not only better for your health but also more sustainable for the planet.
Caffeine is dehydrating and hydration is important for immunity. Too much caffeine can also increase cortisol, the stress hormone, which can compromise our immunity. However, some studies have found that low to moderate consumption may have a beneficial impact on immunity.
What are the Signs of a Weak Immune System?
If you get cold or flu often, this is a sign of a weakened immune system.
In addition, feeling fatigued or lethargic often is another indicator.
How to Improve Your Immune System?
Our daily habits can improve our immune system. This includes everything from our diets, exercise routines, sleep habits, stress management, and mindset.
Food to Build Your Immune System
A whole-food, plant-based diet rich in fruits, vegetables, nuts, seeds, legumes, and whole grains is a good starting point for boosting immunity through our food.
Best Vitamins for the Immune System
Check out this article for more information on these nutrients.
Immune System Supplements
Supplementing with herbs, such as green tea, turmeric and medicinal mushrooms, may be effective for increasing immune functioning.
Immune Support is a herbal supplement that contains these three herbs as well as vitamins C and E.
Hydrate, Hydrate, Hydrate
Drinking plenty of water throughout the day supports a healthy immune system.
Adequate water consumption ensures that blood and lymph are flowing throughout your body.
These biological processes are essential for nutrients to get to the organs, and for waste to be removed.
Does Exercise Increase or Decrease Immunity?
Regular exercise which is light to moderate in intensity can strengthen the immune system.
You want to avoid strenuous exercise as this can weaken our immune system. Intense physical activity can place stress on our body, which affects immunity.
You’ve probably heard stress matters.
But how important is stress for immunity?
The importance of managing stress can not be emphasized enough. When we are in a state of stress, our levels of cortisol rise which leads to handfuls of other negative outcomes.
High cortisol can look like a number of symptoms such as:
- Unexplained weight gain
- Irregular menstrual cycles
- High blood pressure
- Lack of sleep
There are many ways to manage stress. Both yoga and meditation and wonderful tools for managing stress. Studies have found that people who regularly practice mindfulness meditation get sick less often.
The Power of Positive Thinking
Dr. Frederick Lenz, an author, and teacher, once said “The most powerful force to maintaining a good immune system is the power of positive thinking and not allowing yourself to be unnecessarily drained emotionally by worries and fears.”
Our minds are powerful. Studies show that how we think affects how we feel, both positively and negatively.
Optimistic people may live longer and have better longevity.
Research has demonstrated that when stressors are brief (lasting less than a week), women who are optimistic had increased immune functioning compared to women who are pessimistic.
However, when stressors last for longer periods of time, optimism may decrease immune functioning. The reasons for this discrepancy are unknown.
The Importance of Boundary Setting
Whether optimism affects immunity seems to depend on the circumstance and our choice whether to engage or disengage with the stressor.
Sometimes optimism can lead to greater engagement with the stressor, which then increases cortisol levels. Increased cortisol lowers immunity.
This is where the boundary setting may come into play. If we set boundaries around the information we are taking in, and the people we are surrounding ourselves with, we can allow ourselves to disengage from the stressor, and perhaps still maintain optimism.
Another Reason to Quit Smoking
Smoking cigarettes weakens your immune system. Earlier we discussed acrylamides. Smokers have the highest blood levels of acrylamides.
Don’t Forget About Sleep
One of the best actions we can take to boost immunity is to get a good night’s rest. For many insomniacs and night owls, this can be challenging. Try and aim for 7-9 hours of sleep a night.
Sleep hygiene is one way to help support better sleep. This means turning off electronics two hours before bed, avoiding caffeine in the afternoon and evening, setting a consistent bedtime and wake time, and sleeping in a dark room.
Exposure to daylight upon waking will help sleep-wake cycles, as well.
To conclude, our immune systems are complex. There are multiple factors, some of which are out of our control, but many which we can control through lifestyle changes.
It can be overwhelming to try to make a bunch of changes at once, so we suggest choosing a few lifestyle changes at a time, and adding more in overtime.
Health Insiders uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial policy to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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