This medical bulletin discusses dietary fiber, its classification and sources. It notes that dietary fiber is indigestible portions of plants that pass through the digestive system unchanged. There are two types - soluble fiber found in oats and fruits which slows digestion, and insoluble fiber found in wheat and vegetables which speeds digestion. The bulletin recommends adults consume 20-35 grams of fiber daily and outlines several health benefits including preventing constipation, lowering cholesterol, controlling blood sugar levels and reducing risks of colon cancer, diabetes and heart disease. It emphasizes the importance of including fiber from whole foods like fruits, vegetables and grains in a daily diet.

1. Medical Bulletin
Dietary Fiber
Dietary Fiber also known as roughage, is the indigestible portion of food derived from plants, which our body cannot digest or absorb. It therefore, passes virtually unchanged through our stomach, small intestine and into the colon (large intestine).
Dietary Fiber is classified into two categories:
► Soluble Fiber
Soluble fiber tends to slow the movement of food through the Digestive System. Oats, peas, beans, apples, citrus fruits, pulses, gram (chana) and barley are good sources of soluble fiber.
► Insoluble Fiber
Insoluble fiber tends to accelerate the movement of food through the Digestive System. Whole wheat flour, wheat bran, nuts, carrots and many vegetables including green leafy vegetables, cabbage, and tomato are good source of insoluble fiber. This kind of fibre is best known for keeping bowels regular.

2. United States National Academy of Sciences, Institute of Medicine, suggests that adults should consume 20-35 grams of dietary fiber per day.
Fiber Contents of Food

4. It may be noted that Wheat contains of 90% insoluble and 10% soluble, while Oat contains 50% insoluble and 50% soluble dietary fiber.
Benefits of Dietary Fiber
► Prevent Constipation. Insoluble dietary Fiber acts as a broom to sweep out the digestive tract. It accelerates the passage of food through the digestive system, which facilitates regular defecation. Adds bulk to the stool, which is easier to pass, hence decreases the chance of constipation.
If you have loose watery stools, soluble dietary fiber helps to solidify the stool because it absorbs water and adds bulk to stool.
► Lowers the Risk of Digestive Conditions.
A high-fiber diet may lower your risk of specific disorders, such as Heartburn, Gastritis (Acidity), Hemorrhoids (Piles) and Irritable Bowel Syndrome, etc.
► Lowers the Blood Cholesterol Levels. Soluble fiber may helps in reducing total blood Cholesterol levels by lowering Low-Density Lipoprotein (LDL).
► Controls the Blood Sugar Levels. Dietary fiber, particularly soluble fiber, can slow the absorption of sugar from the intestine. It therefore, improves blood sugar levels. A high-fiber diet may also reduce the risk of developing type 2-Diabetes.

5. ► Prevents Colorectal (Colon) Cancer.
► Weight Reduction.
Fiber helps you feel full longer because it stays in your gut for longer periods of time.
This helps to prevent overeating. High fiber diet is lower in calories and fat. Fiber makes you chew food more, so you tend to eat slower.
► Lowers your Risk for Developing Diabetes. Dietary fiber, particularly soluble fiber, can slow the absorption of sugar. High fiber diet is associated with improved glycemic control and lipid profile.
► Lowers your Risk for Developing Heart Diseases. High intake of dietary fiber lowers the risk of heart diseases. In a Harvard University study, researchers found that a high dietary fiber intake has reduced 40 % risk of Coronary Heart Disease.

6. Another study published in the Journal of the American College of Cardiology Foundation that followed 39,876 women for six years, found that those who ingested an average of 26.3 grams of fiber daily were at lower risk for developing heart diseases or having a heart attack than those who ate less.
► Kidney Stones: Since fiber can help to regulate blood sugar, it decreases the chance of insulin spikes that can lead to the formation of Gallstones and Kidney Stones.
Message
Fiber is an important part of a healthy diet and good for health. Therefore, an adult should take at least the minimum recommended (20-35 grams) dietary fiber in his/her daily diet. The best sources of dietary fiber are fresh fruits, vegetables, nuts, gram (Dal Chana) and whole-grain, etc.
We should eat natural fibre rather than taking fibre supplements. Besides fibre, whole food contains nutrients including antioxidants and other biological active components which offer us better protection against chronic diseases.
We should rely more on high fiber diet like vegetables and fruits instead of low fiber diet like meat, chicken, junk food or food cooked/fried in oils, etc.