13 Worst Gut-Ruining Foods No One Should Be Eating Anymore Because They Practically Guarantee Weight Gain: Cereals With Artificial Sweeteners & More

Understanding how your diet affects your gut is key to feeling your best. Some foods can really mess with your digestion, causing bloating, indigestion, and inflammation. These gut-ruining foods can also make you gain weight by throwing off your metabolism and messing with how your body absorbs nutrients. By figuring out which foods are causing issues and cutting them out, you can keep your gut happy and manage your weight better.

We spoke with Alanna Kate Derrick , certified personal trainer and endurance sports nutrition coach; Krutika Nanavati , registered dietitian and nutritionist; Dr. Blen Tesfu ; Lauren Harris-Pincus, MS, RDN ; Johanna Angman , a registered dietitian and nutritionist; and Abby Grimm , MS, RDN, LDN, IFNCP, to learn about 13 worst gut-damaging foods to avoid for weight loss. Some of the culprits were cereals with artificial sweeteners, frozen chicken wings, and granola . Read on to discover all 13.

1. Granola

While granola is often perceived as a healthy breakfast choice due to its whole grain oats and nut content, it can actually contribute to bloating and gut issues for some individuals. Many store-bought granolas are loaded with added sugars and unhealthy fats, which can disrupt digestive function and lead to discomfort.

Derrick elaborates on why this healthy breakfast can be so hard to digest for certain people. "Granolas market themselves as the wholesome, fiber-rich option. But most commercial granolas are also loaded with added sugars and hard-to-digest nuts and seeds that can seriously mess with sensitive stomachs. I've had more than a few rough roll sessions thanks to that combination!" Noted.

2. Smoothies/Juices

Consuming large quantities of sugar in liquid form can lead to spikes in blood sugar levels, followed by crashes, which may disrupt digestion and leave you feeling bloated or sluggish.

Additionally, smoothies and juices often lack the fiber found in whole fruits and vegetables, which is essential for promoting healthy digestion and preventing constipation.

Too much of a certain food can sometimes have its downsides, as Derrick says, "Another culprit is smoothies or juices with lots of greens like kale, spinach or celery," she adds, "Don't get me wrong - I'm all about getting those nutrient-dense veggies in. But blending them on an empty stomach first thing in the morning is just asking for painful gas and bloating until those tough-to-break-down fibers can get properly digested."

3. Overnight Oats

One potential culprit here is the high fiber content of oats, which, while beneficial for many, can be challenging for some digestive systems to process, particularly if consumed in large quantities or if not adequately soaked or cooked.

Furthermore, certain toppings commonly used in overnight oats, such as dried fruits and nuts, can be difficult to digest for individuals with sensitive stomachs or those prone to bloating and could lead to weight gain if consumed frequently.

Overnight oats have been going viral all over the internet thanks to their versatility and convenience, but Derrick reveals, "While oats themselves are great, soaking them can multiply their gut-irritating properties for some people." She also calls out chia pudding by noting that "chia is another fiber-bomb most of us would do better consuming in moderation and especially before training."

4. Cereals With Artificial Sweeteners

Artificial sweeteners, often added to enhance taste without the calories, can disrupt the balance of gut bacteria, potentially leading to an unfavorable microbiome composition. Additionally, studies suggest that the consumption of artificial sweeteners might interfere with the body's natural regulation of appetite, potentially contributing to increased calorie intake and, consequently, weight gain.

"Not only are cereals often low in fiber, high in sugar, and low in nutrients, cereal often contains sugar and artificial sweeteners and sugar alcohols such as erythritol that may disrupt the gut. Sugar alcohols draw water into the digestive system, causing unfavorable symptoms like bloating , loose stools, gas, and stomach cramps. They can also change the makeup of good and bad bacteria in the microbiome," Grimm says.

Grimm further adds that with a deficiency in protein, these food choices can contribute to unregulated high blood sugar levels. Elevated blood sugar, in turn, tends to prompt heightened sugar consumption, ultimately resulting in weight gain. Furthermore, an excess of sugar in the diet can fuel the growth of detrimental gut bacteria, influencing communication with the body and impacting the regulation of weight maintenance.

5. Frozen Pizza Rolls

The dough used in pizza rolls is typically made from refined flour, which lacks fiber and essential nutrients. Refined carbohydrates can cause rapid spikes in blood sugar levels, prompting a quick release of insulin. Over time, frequent insulin spikes can lead to insulin resistance and promote fat storage, particularly around the abdominal area.

Angman states, "Packed with refined carbohydrates, unhealthy fats, and sodium, these can cause bloating, inflammation, and hinder weight loss efforts."

6. Sweetened Yogurt

Sugar-sweetened yogurt, despite its seemingly healthful image, can have detrimental effects on various aspects of well-being. Packed with added sugars, such yogurts may contribute to bloating and digestive discomfort, as excess sugar intake can disrupt the balance of gut bacteria and lead to inflammation.

"Many store-bought yogurts have too much-added sugar, exceeding the recommended daily intake. Excess sugar promotes harmful gut bacteria growth, leading to inflammation, bloating, and digestion issues. Certain yogurts contain artificial sweeteners, which studies suggest could potentially disturb the composition of the gut microbiome and contribute to weight gain," Nanavati says.

As for gut health, she notes that "a lot of flavored yogurts fall short in providing enough fiber, which is crucial for maintaining a healthy gut and feeling full. Insufficient fiber intake can result in constipation and consuming more calories than needed."

7. Dried Fruit

While dried fruits are often thought of as a healthy snack option, it's essential to be mindful of their potential impact on bloating, gut health, and weight gain. Drying fruits concentrates their natural sugars, resulting in a higher calorie density and increased sugar content per serving. Moreover, the high calorie and sugar load in dried fruits may contribute to weight gain if not consumed in moderation.

When it comes to bloating and gut health, Nanavati says "While dried fruit offers vitamins and minerals, its higher natural sugar concentration compared to fresh fruit can disrupt gut bacteria balance, causing bloating. Certain dried fruits may contain sulfites, which are preservatives that could potentially contribute to imbalances in the gut microbiome and digestive problems in sensitive individuals."

These can also impact weight gain, as she says "Despite its small serving size, dried fruit contains a surprisingly high number of calories due to the dehydration process. Excessive consumption of dried fruit can contribute to weight gain."

8. Energy drinks

Energy drinks, often consumed for a quick boost in alertness and energy, can have detrimental effects on gut health and contribute to visceral fat accumulation. Packed with caffeine, sugar, and artificial additives , these highly processed beverages can disrupt the delicate balance of gut bacteria, leading to inflammation and digestive issues. The high sugar content in energy drinks can also spike blood sugar levels, promoting fat storage, particularly visceral fat, when consumed in excess.

Pincus says that they "can cause gastritis, inflammation, increased gut motility, and diarrhea." "It can cause jitters and increase anxiety, which can exacerbate symptoms in people with irritable bowel syndrome (IBS)," she warns.

9. Sugary soft drinks

Loaded with high amounts of added sugars, artificial flavors, and preservatives, these processed beverages, such as soda , wreak havoc in many ways. The rapid influx of sugars from these drinks can spike blood sugar levels, prompting the body to store excess energy as fat. Moreover, the lack of fiber and nutrients in sugary soft drinks further exacerbates their detrimental effects on gut health, potentially paving the way for long-term health complications.

"Sugary soft drinks contain excessive amounts of added sugars, which can lead to an imbalance in gut bacteria and promote the growth of harmful microbes," Tesfu states. "The consumption of sugary beverages can trigger low-grade inflammation in the gut, contributing to gastrointestinal discomfort and other health issues. High sugar intake has also been linked to a decrease in gut microbial diversity, which is essential for a healthy digestive system ."

10. Alcohol

Alcohol, a widely consumed substance, encompasses various types ranging from beer and wine to spirits like vodka and whiskey. Excessive intake can lead to detrimental effects on gut health, contribute to fat accumulation around the stomach, and other serious health issues. Certain types of alcohol, especially those high in sugar and calories like sweet cocktails and fortified wines, can damage your gut health and promote inflammation, ultimately leading to digestive issues and weight gain, particularly around the abdominal area.

"Excessive alcohol consumption can disrupt the balance of gut bacteria, leading to dysbiosis and impaired gut function," she reveals. "Alcohol can damage the lining of the intestines, increasing intestinal permeability (leaky gut) and allowing harmful substances to enter the bloodstream. Chronic alcohol intake has been associated with an increased risk of inflammatory bowel diseases (IBD) like Crohn's disease and ulcerative colitis."

11. Breaded Mozzarella Sticks

While mozzarella sticks provide some protein and calcium from the cheese, they are generally low in essential nutrients and fiber. The lack of fiber means they do not promote satiety, leading to overeating. Moreover, foods low in nutrients can contribute to poor overall diet quality, impacting weight management and gut health.

"These are often loaded with saturated fats and highly processed ingredients, which can disrupt gut health and contribute to weight gain," she says.

12. Frozen chicken wings

The additives, preservatives, and lack of fiber in frozen chicken wings can negatively affect the gut microbiome. A healthy gut microbiome is essential for proper digestion, nutrient absorption, and immune function. Disruption of this balance can lead to increased inflammation, digestive issues , and a higher risk of metabolic disorders.

"Coated in sugary or salty sauces, they're high in unhealthy fats and additives that can disrupt gut bacteria balance and add excess calories," she says.

13. Frozen spring rolls

Spring rolls, especially when deep-fried, can be calorie-dense. The combination of refined carbohydrates from the wrapper and high-fat fillings results in a significant calorie content per serving. Overconsumption of calorie-dense foods can lead to weight gain over time.

Angman states that "despite seeming healthy, they can be high in sodium and unhealthy oils, leading to water retention, bloating, and challenges with weight loss."