4 Surprising Things That Happen When You Eat More Fiber

We know fiber is good for us, but an astounding 90 percent of women and 97 percent of men are falling short on their recommended fiber intakes, according to current Dietary Guidelines for Americans.

While fiber, a type of carbohydrate that our bodies cannot fully break down found naturally in fruits, vegetables, whole grains, beans, legumes, nuts, and seeds, is widely recognized for its ability to improve digestion, the benefits of eating more fiber are not limited to our gastrointestinal (GI) tract. Fiber impacts nutrient absorption, hormones, and serves as food for our good gut microbes, leading to a variety of surprising health benefits.

Here are 4 lesser-known health effects of eating more fiber

1. Your energy levels may become more stable throughout the day

If you’ve ever felt shaky, fatigued, hungry, or lightheaded an hour or so after eating a carb-heavy meal, a lack of fiber may be partially to blame. When we eat foods that contain carbohydrates, they’re broken down into sugar, which enters the bloodstream and raises blood sugar levels. In response to our rising blood sugar, the hormone insulin is released.

Insulin acts like a key, allowing sugar to enter our body’s cells to either be used for energy or stored for later. Blood sugar levels drop once the sugar enters our body’s cells, which may lead to those unpleasant symptoms of hypoglycemia. While some degree of blood sugar fluctuation throughout the day is perfectly normal and healthy, large spikes and dips can leave you feeling lousy and increase your risk for developing metabolic issues down the road, like insulin resistance or diabetes.

When it comes to blood sugar stability, fiber is your best friend. It slows the absorption of glucose into the bloodstream, helping to prevent large spikes and subsequent crashes. Choosing carb sources rich in fiber promotes stable blood sugar, which also means sustained energy levels and greater satiety¹. Think: beans and legumes, vegetables, fruits like berries and apples, and whole grains like quinoa and barley. Not only are these foods less likely to cause large blood sugar spikes compared to refined carbs and simple sugars, they’ll also keep you full for longer since their fiber content causes them to be digested more slowly.

2. Your LDL cholesterol may go down

Low-density lipoprotein, or “LDL” cholesterol is often referred to as the “bad cholesterol.” This is because having high levels in your blood increases your risk for developing cardiovascular disease. When it comes to lowering your LDL, high-fiber foods are some of the best you can eat, as certain fibers are particularly adept at helping to lower cholesterol levels.

Soluble fiber is a type of fiber that forms a viscous gel in the GI tract, binding with cholesterol so that it’s excreted rather than absorbed³². This gel also binds to bile acids that our bodies produce from our own cholesterol to help break down foods we eat. Normally, we reabsorb bile acids in our intestine so they can be recycled. When soluble fiber binds with them, however, they can’t be reabsorbed. Instead, we make more bile acids out of our own cholesterol, lowering blood cholesterol as a result.

You can find soluble fiber in the fleshy parts of fruits and vegetables, the inner portion of beans and legumes, and in certain nuts, seeds, and grains. Some of the highest sources of cholesterol-lowering soluble fiber include foods like chia seeds, lentils, oats, oat bran, barley, apples, bananas, and potatoes. Adding a sprinkle of chia seeds to your morning oatmeal, topping a salad with lentils, and incorporating barley and potatoes into a hearty soup are all tasty ways to boost your soluble fiber intake and support a healthy blood lipid profile.

3. You may lower your blood pressure

High blood pressure increases your risk for developing heart disease and stroke, and it’s more common than you may think. In fact, almost half of U.S. adults are estimated to have high blood pressure according to the CDC.

Eating fiber-rich foods can help to lower your cholesterol, which may lead to improved vasodilation⁵⁴. This means blood vessels are better able to expand, causing blood pressure to decrease. Additionally, higher fiber intakes are associated with improved metabolic health, which is also linked to lower blood pressure.

4. Your bone density may improve

Bone health may not be the first thing that comes to mind when you think of fiber, but recent research shows that certain fibers can actually improve our calcium absorption. Since over 99 percent of calcium in the body is found in our bones⁶, regularly consuming foods rich in these fibers may improve bone density over time. This means reduced risk for bone fractures and conditions like osteoporosis and osteopenia down the line.

Certain fibers have prebiotic properties, meaning they feed our good gut bacteria, encouraging a healthy gut microbiome. When these bacteria are well-fed, they produce special anti-inflammatory compounds called short-chain fatty acids. Interestingly, research⁷ suggests that these short-chain fatty acids make minerals like calcium and magnesium more absorbable by changing our colon’s pH.

The prebiotic fibers most strongly associated with improved mineral absorption are called fructooligosaccharides (FOS). You can find them in foods like asparagus, artichokes, garlic, onions, barley, and chicory.

How much fiber is enough?

Current guidelines from the Institute of Medicine (IOM) recommend that men aim for 30-38 grams of fiber daily and women, 21-25 grams of fiber daily. That said, keep in mind that these targets were established based on the amount of fiber considered adequate to maintain heart health and bowel regularity. Research⁸ suggests that additional fiber is likely to produce further health benefits and support your gut microbiome.

Before you start loading up on lentils and sprinkling chia seeds into everything you eat, it is worth noting that increasing your fiber intake too quickly can lead to digestive discomfort. It’s best to start “slow and low,” gradually ramping up your fiber intake over a few weeks. Be sure to drink plenty of water, too, to ensure things move through smoothly.