#1- Aids in Digestion and Elimination
While both types of fiber have their roles in digestion, insoluble fiber is especially important since it provides bulk to the stool (helping you poop!). Insoluble fiber helps speed up the time it takes waste to pass quickly through the digestive tract, which prevents constipation, bloating and indigestion. Soluble fiber absorbs water to become a gelatinous, viscous substance and is fermented by bacteria in the digestive tract, which also improves digestion.
At the same time, fiber needs to absorb water to have these effects, so when you begin eating a high-fiber diet in earnest, drink plenty of fluids throughout the day for the best digestive relief.
#2- Helps Prevent Heart Disease
Research shows there’s an inverse association between insoluble fiber intake and systolic and diastolic blood pressure, total cholesterol levels and triglycerides. In addition, soluble fibers also help lower LDL (“bad”) blood cholesterol by interfering with the absorption of dietary cholesterol.
According to studies, the more pronounced the high-fiber diet, essentially the less likely that person is to experience hypertension and other risk factors of heart disease and metabolic syndrome. For example, historically, because the Mediterranean diet is naturally a high-fiber diet due to a high consumption of vegetables, fruit, beans and whole grains, this population has been at a much lower risk for heart disease than many Americans are today.
#3- Makes You Feel Full, Which Helps with Weight Loss
Epidemiologic evidence from numerous studies supports that a high-fiber diet helps prevent obesity. Fiber intake is inversely associated with body weight and body fat, so the more consistent you are with your high-fiber diet, the likelier you are to stay at a healthy weight or lose weight if you need to.
If your goal is to reduce to your weight, fiber can help since it makes you feel fuller after eating and can prevent snacking or overeating at your next meal. Results from intervention studies show that the addition of a high-fiber diet generally decreases food intake overall and, therefore, over time can contribute to a lower body weight. But there might be other benefits of fiber for weight loss too, such as decreasing absorption of toxins and altering secretion of gut hormones.
#4- Helps Control Blood Sugar and Prevents Diabetes
The effects that soluble fiber have on the rate at which the stomach empties helps slow down digestion and keeps blood sugar levels stable. This improves insulin sensitivity and can help control the blood sugar spikes and conditions like diabetes.
According to studies, within the body there’s an inverse association between levels of glucose in the blood and dietary fiber, so increasing fiber by following a high-fiber diet can prevent insulin resistance that forms from elevated glucose levels over time.
#5- Prevents Diseases of the Digestive Tract
A high-fiber diet helps prevent digestive disorders and diseases like diverticulitis, colon cancer and inflammatory bowel disease. This is because prebiotic fiber helps improve immune function and maintains better colon and intestinal health, while also clearing away harmful waste from the digestive organs. Additionally, a high-fiber diet is correlated with a lower risk for many other types of diseases, including cancer and heart disease.
How does eating a high-fiber diet protect you from disease? There is increasing evidence that fermentable dietary fiber (prebiotics) modulate various properties of the immune system, including those of the gut (specifically the lymphoid tissues or GALT). Changes in the intestinal microflora that occur with the consumption of prebiotic fiber can potentially increase immunity by changing the way the body responds to acids or bacterias.