Eating Sugar Can Weaken Your Immune System. Here's What To Know.

While a strong immune system is no match for the power of social distancing when it comes to limiting the spread of COVID-19, it’s certainly top of mind these days. As coronavirus spreads at an alarming rate in the United States, we’re all doing our best to stay healthy — and relying on our immune system to help make that happen.

At the same time, most of us are spending our days and weeks at home now, which can mean frequent visits to the cupboards for cookies and the freezer for ice cream. We’re looking for all the comfort we can get these days, so what’s the harm in a little sugar?

Potentially a lot, as it turns out. The studied harmful effects of sugar run the gamut from increased anxiety to early death. Oh, and a suppressed immune system. 

Yes, there’s some research to back up the idea that sugar wreaks havoc on the immune system. But just how seriously should we take it? Let’s take a closer look.

Your Body On Sugar

While sugar found in fruit or other natural sources can give the body a little boost (mostly because it’s paired with great-for-your body things like fiber and vitamins), processed sugar tends to have some unpleasant effects on the body as a whole.

“Consuming too much sugar can affect the cells in your immune system that target bacteria. ... Sugar affects the way your white blood cells attack bacteria.” explained board-certified internist and gastroenterologist Niket Sonpal. “Nutrient deficiencies can increase your risk level when warding off infection, and food items with high levels of refined sugar are usually nutritionally obsolete. Sugar triggers low-grade inflammation in the body and also increases the mass. This can contribute to diseases that are chronic in nature, things as cardiovascular disease and diabetes.” 

Nate Favini, medical lead at Forward, added that it would be misleading to say that we fully understand the relationship between sugar and our immune system. “What we do know is that diabetes appears to be common in people confirmed to have COVID-19,” he noted. “This suggests that having higher levels of sugars in your blood could make it easier to contract COVID-19.” 

So how much sugar is too much sugar? 

So, should we back slowly away from the ice cream pint and not even consider touching it until this is all over? According to Sonpal, you probably have to consume a lot of sugar to see a real impact — but grams of sugar can add up very quickly. 

“Research does show that consuming 75 to 100 grams of a sugar solution can hinder the body’s immune functions,” he said. “I should note that 75 grams sound like a lot, and it’s hard to think you may be consuming 75 grams of sugar, but really all it is is the equivalent of two cans of your soda.”

Sonpal is right: A 12-ounce can of Coca-Cola contains 39g. And soda isn’t the only culprit. A grande chai latte from Starbucks, for example, contains 42 grams of sugar, which gets you more than halfway to lowering your immunity. 

He added that the suppression of the immune system starts as soon as 30 minutes after the consumption of sugar and can last up to five hours. 

Again, the very best thing you can do for your health right now is practice social distancing. But if you do need to do something that will require you to be around other people — like go to the grocery store — it may be worth waiting until at least five hours after you consume sugar. You can’t be too safe these days. 

How to keep your immune system in tip-top shape. 

As long as you keep an eye on those grams, having a little bit of sugar every day probably isn’t the worst idea. But there are other ways to boost your immunity other than cutting back on sugar — like loading up on healthy foods. “Citrus fruits such as grapefruit, oranges, and tangerines are great along with vegetables like broccoli, garlic and spinach,” said Sonpal. “Other helpful items to pick up and incorporate in your diet are ginger, yogurt, almonds, turmeric, green tea, poultry and shellfish. The better we nourish our bodies over time, the better prepared it is to protect itself against illness.”  

Marion Nestle, a nutrition and food studies professor at NYU, added that eating a veggie-rich diet is key, along with other lifestyle factors. “Don’t drink much alcohol, don’t smoke cigarettes, get plenty of sleep, and, these days, keep your social distance,” she said.

Long story short: A lot of factors go into building a resilient immune system, including limiting processed sugar and filling up on good-for-you fruits, vegetables and proteins. As a nice bonus, eating a healthy diet helps you feel better both physically and mentally, which we all desperately need right now. Why not try it? 

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