"Eat more fiber." This seems to be the blanket solution to many a health woe. But just why is fiber so fabulous and healthful?

Fiber or roughage is the indigestible part of a plant that pushes through our digestive tract. There are two main types of dietary fiber: soluble and insoluble. Soluble fiber, such as bran, nuts, seeds and beans, holds water and turns to gel during digestion. Insoluble fiber, by contrast, speeds the passage of foods through the stomach.

Types of insoluble fiber include wheat bran, vegetables, and whole grains. The current recommendation for daily fiber intake is 25 grams for women and 38 grams for men. (These needs decrease after age 50.)

Getting an adequate amount of fiber in your diet, especially the soluble variety, relieves constipation and other tummy troubles. It adds bulk to the stool, which makes it easier to pass; helping to prevent constipation, hemorrhoids and diverticulitis (inflammation of the intestine), as well as relieving some of the symptoms of irritable bowel syndrome (IBS), such as diarrhea, abdominal pain, and gas.

But that's not all—eating more high fiber foods can do for your health. They require more chewing so it takes longer to eat and digest them. Your body recognizes this and feels full sooner. This is why increasing your fiber intake will aid in weight loss and weight maintenance efforts. In particular, fiber may reduce abdominal obesity, which is part of a cluster of symptoms known as metabolic syndrome that increase risk of heart disease. Eating more fiber-rich vegetables, fruit and beans can reduce belly fat. For every 10-gram increase in soluble fiber eaten per day, belly fat was reduced by almost 4% over five years, research showed.

There's more. Fiber also helps lower serum cholesterol levels, and high cholesterol is considered a major risk factor for heart disease. A landmark study out of Boston's Harvard University showed that men who consumed the highest levels of dietary fiber (around 28.9 grams per day) had a 40% lower risk of heart disease. The main sources of fiber in this study were vegetables, fruit and cereal.

Fiber is indigestible meaning it passes through the digestive tract, so it is less likely to cause blood sugar to spike. In fact, individuals with diabetes who ate 50 grams of fiber a day had tighter blood sugar control than those who ate considerably less.

There are so many reasons to increase the amount of fiber in your diet. For tips on how to get more in your day, talk to your doctor or a registered dietician.