‘I’m a Gastroenterologist, and This Is What Happens When You Cut Added Sugar’

Doctors and dietitians may have debates about the health benefits of meat, carbs, or caffeine, but virtually all health experts take a united stance against added sugar. Essentially, eating it in excess leads to poor health. Scientific studies have repeatedly shown that added sugar causes inflammation, which affects the entire body: brain, heart, gut—all of it.

It would be impossible—and unhealthy—to cut ties with sugar entirely since it’s found in some foods that are rich in nutrient value. Registered dietitian Brigitte Zeitlin, MPH, RD, CDN previously explained to Well+Good that there are two types of sugar: simple sugars, which are naturally occurring and become carbohydrates (like those found vegetables, fruits, and grains), and refined sugars, which come from the sugar cane plant and are used to make processed and sweetened foods, like baked goods, cereals, and white flour products. Cutting sugar out of your life entirely in an attempt to affect gut health would mean missing out on the nutrient values found in veggies, fruit, and grains. It’s refined sugar that doctors and dietitians are referring to when they talk about added sugar, which is what is causing inflammation.

The link between sugar and gut health is an especially important one because gut health affects, well, everything. This includes, but isn’t limited to, digestion, mood, immunity, and cognitive function. “When it comes to added sugar and gut health, there’s still a lot we don’t know. But scientific studies do suggest that it promotes an inflammatory profile in the gut and damages the microbiome,” says gastroenterologist and Fiber Fueled author Will Bulsiewicz, MD, referring to the population of bacteria that lives in the gut. “It makes sense that what we eat determines the makeup of our gut bacteria.”

What happens to your gut health after cutting out added sugar

If added sugar is likely causing inflammation in the gut, what happens to your gut when you remove added sugar from your diet? Will you experience sugar withdrawal symptoms? Dr. Bulsiewicz says many people experience balance. “If you eliminate foods that we know are damaging to the gut, like sugar, and what you’re left with is foods that we know to be good for the gut, that will bring more balance to the gut,” he says.

When the gut is balanced, this means the good bacteria is thriving; a gut imbalance is when there is more bad bacteria in the gut than there should be, which then can cause a variety of health problems such as digestive issues in the short term and cognitive decline and chronic disease in the long term.

Dr. Bulsiewicz says if you minimize added sugar and fill up on nutrient-rich foods instead, balance is established, which leads to better digestion and feeling better overall. (The caveat to this is if you have any underlying health issues, which requires working with a doctor to get to the bottom of.)

When healthy bacteria is thriving in the gut and the bad guys are kept at a minimum, you can expect your digestion to improve (and yes, that means better poop), your skin to look its best, brain fog to decrease, and your mood to enhance. It’s all connected to going on what’s going on in your gut.

What should you replace refined sugar with?

While minimizing foods high in added sugar is good for gut health, it can be super difficult to nix it completely. This is especially difficult for people who live in food deserts and do not have access to grocery stores full of trendy snack products made with natural sweeteners instead of refined sugar. Making any dietary change requires at least some extra planning and money.

Instead of making a goal to cut added sugar completely, it may make more sense to aim to stick within the recommendations U.S. Dietary Guidelines for Americans. These guidelines advocate for keeping added sugars at 10 percent of daily calories.

If you’re cutting back on refined sugar, it’s natural to wonder what to replace it with. Sugar replacements are a popular option for people looking to give up added sugar but still have a bit more dietary flexibility. But not all of these alternative sweeteners are created equally. “[Society] has celebrated artificial sweeteners because they are zero calorie, and the reason why they are zero calorie is because they aren’t absorbed in the body,” says Dr. Bulsiewicz. “But that doesn’t mean it doesn’t alter the microbiome; everything you consume alters the microbiome in one way or another.” Artificial sweeteners could potentially be linked to insulin resistance because they still spike blood sugar levels, he adds.

When it comes to gut health, Dr. Bulsiewicz is a straight-shoote; what’s best for the gut is no sweetener at all, he says. But he also gets that it’s human nature to desire sweets, so most people aren’t going to live a life void of anything sweet. He has some added sugar guidelines to best support gut health. First, minimally processed options (like fruit and nut bars or yogurt) are better than processed (like cupcakes and candy). Second, maple syrup, agave, and honey at least have some nutrients (such as zinc in maple syrup, vitamin K in agave, and magnesium in honey), so they can offer a bit more nutritionally than artificial sweeteners. Third, the best sweet food of all you can have is fruit in its whole form. That’s because fruit has fiber and nothing is better for the gut than that.

Just because sugar isn’t great for your gut doesn’t mean it doesn’t have any value whatsoever. Its primary value is that it tastes good and sometimes you just want to eat something that will provide you with some temporary happiness. But if you feel crumby all the time and happen to have a diet high in sugar, it may be worth taking a look at. Cutting your intake back could just be the solution to feeling more well. When sugar takes a backseat in your life, it allows other, more nutrient-rich foods to take center stage. And that’s bound to make your body happy, gut included.

Watch the video below for more information about how what you eat affects your gut health:

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