When it comes to health, it seems like every friend group has someone who's always getting sick and someone else who seems to be immune to everything. Although there are many factors at play when it comes to your body's immunity, there are certain foods that can actually hurt your immune system, so your diet is an extremely important part of protecting you from illness. Just as certain foods can protect your body from catching the flu or a cold, others can contribute to sickness and disease.
"It's important to recognize that everything you put into your body can affect you in a positive or negative way," says Tiffany Newenhouse, RD to me over email. "Every body is unique, and some underlying food sensitivities may be heightened in some with varying conditions than others."
Although any food you have a sensitivity to may affect you worse than others, there are a variety of foods that cause inflammation and affect immune responses in pretty much everyone. And no, you don't have to give any of this up for good (in fact, I'd never recommend that) but if you've been feeling more sickly lately, you might try swapping some of these seven foods for something else.
"Sometimes our systems get shocked by the presence of lactose," says Newenhouse. "This sugar is found in animal milks were that were designed for specific species infants, so it's not surprising that an adult human can have some gastrointestinal upset when drinking or eating dairy products." Approximately 65 percent of people are lactose intolerant, so it's no wonder some people might have issues after indulging in the food group.
Studies from the journal Alcohol found that drinking alcohol can affect your immune system, even just 20 minutes after consuming a drink. Alcohol causes inflammation in the body, and this can last for days after consumption.
If consumed in excess or too late in the day, caffeine can have an indirect role on your body's immune system. "Caffeine will also obviously affect your sleeping patterns," says Newenhouse. "This alone can lead to a whole other slew of issues such as hormone imbalance, immune function, digestion troubles, memory loss, and weight gain."
4. Red Meat
Red meat contains saturated fat, which can trigger inflammation in the body. Research published in the journal Proceedings of the National Academy of Sciences found that the body views red meat as a foreign invader, which sparks an immune response.
"[Soy is] one of the biggest GMO crops produced in the country," says Newenhouse. "If it was designed in a lab, it gets further and further from its original form. Not to mention soy can have a detrimental effect on thyroid hormones, which can be exacerbated by other common nutrient deficiencies and ultimately affect your metabolism."
Sugar inhibits your body's immune response by causing a drop in white blood cells' ability to engulf foreign bacteria, according to Dr. Bill Sears', a clinical professor at several universities. Just 75 to 100 grams of sugar can have this effect, which is only equivalent to about two cups of soda.
7. Fast Food
All the unhealthy components of fast food, including processed ingredients, sugar, salt, and fat, can have an impact on immune function. A study from Nutrition Journal found that consuming these foods can lead to inflammation, reduced control of infection, a higher risk of cancer, and increased risk for allergic and auto-inflammatory disease.
Next time you're feeling under the weather, you may want to pay attention to what you're eating and stick to whole, unprocessed foods that are abundant in fruits and vegetables.