Top News

Most people think of fiber as something that simply keeps you regular, but its benefits extend far beyond digestion. This often-overlooked nutrient plays a surprisingly powerful role in overall health—impacting everything from energy and appetite to long-term metabolic health. One of fiber’s most important functions is helping to regulate blood sugar, which is important for everyone and especially for those with insulin resistance or type 2 diabetes.

To get a clearer picture of why fiber deserves a starring role on your plate, we spoke with dietitians to explain what happens to your blood sugar when you eat fiber, how to easily add more to your diet and other practical strategies to support blood sugar balance.

Why We Love Fiber for Managing Blood Sugar

Slows Down Carbohydrate Absorption

When it comes to keeping blood sugar levels in check, fiber’s biggest advantage is its ability to slow sugar absorption. “Fiber slows the absorption of carbohydrates from the small intestine to allow a slower and steadier release of glucose into the bloodstream,” says Megan Koehn, RDN, LD. This gradual release is why fiber—especially soluble fiber—helps prevent sharp spikes and crashes in blood sugar.

By keeping blood sugar levels more stable, fiber also reduces the amount of insulin the body needs to release at once. Insulin is the hormone responsible for moving glucose (sugar) into cells to be used for energy. As such, fiber helps to support better insulin sensitivity over time.

Feeds Gut Bacteria Involved in Blood Sugar Control

Most people know that fiber is great for your gut microbiome, but what they don’t know is that it can play a surprising role in blood sugar management. “Your gut microbiome is a complex ecosystem of living microbes that live in your intestines. Maintaining a healthy gut is essential for glucose management because dietary fiber supports the fermentation process carried out by the good bacteria of the gut,” says Kimberley Rose-Francis, RDN, CDCES.

When gut bacteria ferment fiber, they produce byproducts like short-chain fatty acids, which are linked with improved insulin sensitivity and, ultimately, more stable blood sugar. Research also shows that a diverse gut microbiome is associated with a lower risk of type 2 diabetes, while gut dysbiosis—an imbalance between “good” and “bad” bacteria—is linked with increased inflammation and a higher risk of developing the condition.

Supports Satiety and Steady Energy

Another major benefit of fiber is its ability to keep you full and sustain energy throughout the day. “Soluble fiber is a type of dietary fiber that absorbs water and forms a gel-like substance in the digestive tract. This property is important because it can enhance the release of hormones that promote satiety, the feeling of fullness after eating, which may help reduce food intake and lower blood glucose levels,” explains Rose-Francis.

Koehn adds that because fiber slows digestion and absorption, it allows your body to use energy from food more gradually. This helps you stay full longer and maintain steady energy levels until your next meal.

How Much Fiber Do You Need?

You may be wondering how much fiber it actually takes to support healthy blood sugar levels. Although everyone’s fiber goals will look a little different, general recommendations suggest that women aim for at least 25 grams of fiber per day, and men aim for 34 grams or more.

Rose-Francis notes that the 2020-2025 Dietary Guidelines for Americans outlines that fiber intake for adults is based on calorie intake. “Adults should aim for 14 grams of fiber for every 1,000 calories eaten,” she emphasizes. To put that into perspective, someone eating 2,000 calories should aim for 28 grams of fiber per day.

Unfortunately, “studies show that only about 5% of Americans meet the recommendations,” says Koehn. For the 95% of people who fall short, reaching 25 grams or more each day may feel overwhelming. To make it more approachable, Koehn suggests aiming for 7 to 10 grams of fiber per meal and 4 to 6 grams of fiber for each snack.

If you’re new to fiber, it’s important to start slowly, gradually increase your intake and be sure to drink plenty of water to support digestion.

Food Sources

Along with hitting your fiber targets, it’s important to consider the types and sources of fiber that benefit blood sugar. “While soluble fiber is more effective for immediate blood sugar stability, consuming a mix of soluble and insoluble fiber is essential,” says Koehn. Soluble fiber helps absorb excess sugar, while insoluble fiber supports bowel regularity and a healthy gut microbiome. Together, both types work hand in hand to promote balanced blood sugar.

Eating a variety of plants will help you meet your fiber needs. Here are some examples of high-fiber foods:

• Whole Grains: Oats, wheat, wheat bran, popcorn, teff, spelt, etc.
• Legumes: Lima beans, green peas, navy beans, black beans, kidney beans, chickpeas, green peas, etc.
• Nuts and Seeds: Pumpkin seeds, chia seeds, flaxseed, pine nuts, pistachios, peanuts, etc.
• Vegetables: Brussels sprouts, sweet potatoes, leafy greens, artichokes, broccoli, pumpkin, potatoes (with skin), etc.
• Fruit: Berries, apples, pears, avocado, kiwi, guava, sapodilla, passion fruit, oranges, bananas, etc.

Other Ways to Manage Blood Sugar

In addition to eating more fiber, both dietitians share several other ways to keep your blood sugar levels steady:

• Walking Daily. Koehn explains that walking is essential for maintaining stable blood sugar. Walking, particularly after eating, has been shown to improve blood sugar control in those with type 2 diabetes.
• Strength Training. Both dietitians recommend regular strength training to support optimal blood sugar levels. Kohen shares that strength training has a major impact on reducing insulin resistance, lowering HbA1c—a 3-month average of blood sugar—and supporting weight loss. She recommends strength training two to three times per week to help build muscle and improve insulin sensitivity.
• Stay Hydrated. Drinking plenty of fluids can also help with blood sugar management. Rose-Francis suggests beverages like water, herbal teas and infused water for low-calorie and sugar-free options. “Sugary drinks, such as regular soda, hot cocoa and juice, may seem refreshing and hydrating, but they can cause a rapid spike in blood sugar,” she warns.
• Get Enough Sleep. With long to-do lists and busy schedules, it’s easy to miss out on sufficient sleep. However, a healthy sleep routine can support healthy blood sugar levels. “During sleep, our body heals itself from stress and regulates hormones (including insulin),” says Koehn.

Our Expert Take

If your goal is balanced blood sugar, fiber is one nutrient you want on your plate. It helps by slowing glucose absorption, nourishing beneficial gut bacteria and supporting steady energy and satiety—all key factors for blood sugar balance. To boost your fiber intake, regularly include plant-based foods such as whole grains, beans, fruits, vegetables, nuts and seeds. Equally important are lifestyle habits like regular exercise, adequate hydration and getting enough sleep. By pairing fiber with these healthy lifestyle habits, you’re helping your body keep blood sugar levels in check.