Bran is made up of the fibrous husks which cover grain seeds. It contains 9 to 12% complex carbohydrates such as cellulose, pectin and lignin, and also protein, fat, vitamins and minerals. 

It is very nutritive, the unique characteristic of bran is its ability to absorb water and give bulk to the faeces. It expands in the colon, stimulating the involuntary contractions of evacuation.

It is rich in fibre which speeds up waste transit time through the colon, preventing constipation, appendicitis, diverticulitis, hemorrhoids and varicose veins, obesity, high blood pressure, cancer of colon and coronary heart disease.

With slow moving stools, bacteria in the colon have time to convert bile acids to carcinogens; where as fast moving stools facilitate bile excretion and therefore the excretion of cholesterol, reducing hypertension and the risk of heart attacks.

In low fibre diets, evacuation is generally incomplete, and the stools are relatively dry and hard which press on weak parts of the colon, causing it to pouch and bulge. The result is diverticulosis, diverticulitis, hemorrhoids and appendicitis.

It should be noted that when you take bran or high fibre diet, one should drink plenty of water to enable it to expand. Without adequate water bran can have the opposite effect, hardening of stools and contributing to constipation.

Chewing is essential to ensure optimal fibre function in the intestine and colon.