How to Eat to Boost Your Immune System
The human immune system is a wonderful thing. It responds quickly when we’re injured (the swelling around a sprained joint or a small cut), it attacks microscopic invaders like viruses and bacteria, and it even stores information that helps it fight future infections. It’s a beautiful protector that we’re partially born with and partially develop throughout our life.
Unfortunately, our lifestyle often undermines that system. For instance, stress weakens our immune system. So does a lack of sleep. Being sedentary can lead to immune system dysfunction. And depression, anxiety — even grief — take their toll.
As does our Western diet, which is filled with processed and ultra-processed foods but low in immune-boosting ingredients. While many people are correct in connecting nutrition with a strong immune system, the relationship between the foods we eat, and our body’s defensive shield is far more complex than simply drinking orange juice or chicken soup during cold and flu season.
Foods that Cause Inflammation
Bad diets damage our immune system in surprising, contradictory ways. Processed and ultra-processed foods, for example, are linked to inflammation – a component of our immune response.
When we get hurt or have an infection, there’s a localized immune response: Blood flows to the area, small blood vessels dilate and white blood cells rush in to fight the infection and begin repairing damage. The process raises inflammation levels as a result, which is normal, even necessary.
But sometimes our immune system stays active long after the initial response is over and no longer needed. This is called chronic inflammation – and it’s harmful. Chronic inflammation is linked to many diseases such as diabetes, heart disease, nonalcoholic fatty-liver disease, obesity, depression and autoimmune disorders. It also impairs our immune response, making it more likely an infection can take hold.
What’s the connection between diet and chronic inflammation? Specific foods like red meat, sodas, simple carbs like white bread, pasta and pastries, fried foods, some vegetable oils and processed meat contribute to inflammation. Studies link sugar (including high-fructose corn syrup), trans fats (often found in processed foods) and red and processed meats to inflammation and disease.
How You Should Eat for Your Immune System
As we get older, the problem gets worse. Older Americans who are frail, obese or malnourished tend to experience a weaker immune response. Diets heavy on convenience foods tend to be short on essential micronutrients that strengthen our immune system.
Micronutrients include vitamins — A, B-complex C, D and E — and minerals — calcium, phosphorus, magnesium, sodium and potassium. A balanced diet that is comprised of good sources of micronutrients (fruits, vegetables, whole grains, dairy products and lean meat, poultry and fish), along with soluble fiber (legumes, Brussels sprouts, sweet potatoes), healthy fats (avocados, olive oil, nuts and seeds) and healthy proteins (lean meats, poultry and fish) can actually boost your immune system.
This is one reason health experts promote the Mediterranean diet. It’s loaded with immune-boosting foods such as olive oil, fish, fruits, vegetables, legumes and whole grains while limited in processed foods and red meat. The Mediterranean diet also is credited with maintaining a healthy gut – another key element of strong immunity.
Foods that Boost Your Immune System
The best way to absorb these nutrients and reap their benefits is by eating them as part of a healthy diet, as opposed to taking supplements. Here are some examples of immunity boosting foods that you can integrate in your diet:
- Citrus, vegetables like peppers and fruits like papaya are significant sources of vitamin C, which is thought to improve the production of white blood cells.
- Orange vegetables -- carrots and sweet potatoes -- have beta-carotene, which turns into vitamin A and supports your immune system.
- Cruciferous vegetables such as broccoli, cauliflower, Brussels sprouts, kale and arugula are powerhouses of vitamins that help your immune system including A, C and E. They also have fiber, which supports the growth of certain valuable microbes that in turn help your immune system.
- Many seeds and nuts contain vitamin E, which helps modulate your immune system. They also have trace minerals like selenium, phosphorus and magnesium, which have been shown to boost immunity.
- Dairy products, particularly milk and yogurt, and along with mushrooms and some fatty fish also are good sources of vitamin D, which has anti-inflammatory properties and helps balance and regulate the immune system.
- Ginger and garlic, common cooking ingredients, are high in antioxidants and have anti-inflammatory, antiviral and antibacterial benefits – all beneficial to the immune system.
What about alcohol?
Finally, alcohol also affects your immune system in several ways. It can destroy microbes in your digestive tract that support your immune system. It also leads to inflammation. The more you drink, the greater the effect.
Nutrition is just one factor — an important one — in our immune system’s health. In addition to eating well, we also need to exercise, keep our weight in check and manage our stress. Doing all these things can be a recipe for immunological success.