Bran has a bad reputation. The word brings to mind moms forcing kids to eat cardboard-like breakfast cereal, and people self-imposing that same boring cereal on themselves in order to lose weight. But a bran diet, high in fiber, has many health benefits and does not have to be dull or tasteless.
What Is Bran?
Grains, also known as cereals or cereal grains, are the edible seed parts of grasses that belong to the Poaceae family. Some examples of grains are wheat, corn, rice, oat, barley, rye and millet. Each kernel of a whole grain has three main parts: the bran, germ and endosperm.
The bran is the hard outside shell of each grain kernel, which is high in fiber and nutrients such as B vitamins and copper, zinc and magnesium. Although bran is just one source of fiber, "bran" and "fiber" have become synonymous in food marketing.
The germ is the lower part of the kernel, which can sprout into a new plant and is rich in fats and vitamin E. The endosperm is the grain's interior, which is high in starch and serves as food for the kernel, similarly to how the yolk serves as food for a growing baby chick inside an egg shell.
Read more: Eating Wheat Bran Flakes for Weight Loss
When grains are processed into flour, the bran and germ of the grain kernels are often removed. By only leaving the soft endosperm, the grain is easier to chew and digest. The shelf-life of the grain is also prolonged by removing the bran and germ, which are higher in fat-content and can turn rancid quickly.
Processed grains are much lower in nutrients than whole grains. For example, refined wheat contains only half of whole wheat's B vitamins, 10 percent of its vitamin E and nearly no fiber. There is a growing body of research that shows that eating whole grains, with the bran and germ still intact, over processed grains improves health in many ways. This research has helped fuel the popularity of bran- and fiber-heavy diets.
Benefits of Increased Fiber
If you're wondering about all-bran cereal health benefits, there are plenty. According to an April 2017 study published in the Journal of the American Association of Nurse Practitioners, nearly 95 percent of American adults do not consume enough fiber. A fiber intake of about 25 grams per day for adult women and 38 grams per day for adult men is recommended.
The benefits of consuming fiber, of which bran is a great source, are numerous. Fiber intake is correlated with decreased risk of cardiovascular disease. A December 2017 review published in the Journal of Chiropractic Medicine concludes that consuming dietary fiber significantly reduces incidence of and mortality from diseases such as coronary artery disease, high blood pressure, cardiac arrest and congestive heart failure.
Fiber also helps lower cholesterol and move waste through the digestive tract. If you struggle with bloating, constipation or bowel irregularity, upping your fiber intake might help relieve your symptoms, as it will bulk up your stool and increase the speed at which it moves through your digestive tract.
Read more: List of Foods High in Soluble Fiber
Both bran and fiber also help maintain steady blood glucose levels because they help slow the breakdown of starch into glucose. As such, bran and fiber are good food options for individuals with hypoglycemia or Type 2 diabetes.
Another benefit of fiber is that it may prevent clot formation and therefore decrease the risk of heart attacks and strokes caused by blood clots. Due to all of these benefits, eating all-bran products such as cereals and baked goods is one simple way to increase your fiber intake and improve overall health.
Kellogg's All-Bran Diet
"All-Bran" was first coined by the cereal brand Kellogg's, which introduced Bran-Flakes in 1915, followed by Kellogg's All-Bran in 1916. The company's "All-Bran" line is trademarked and now carries three different cereals: Kellogg's All-Bran Original Cereal, Kellogg's All-Bran Bran Buds Cereal and Kellogg's All-Bran Complete Wheat Flakes Cereal. A serving of these cereals contains between 5 and 13 grams of fiber.
Read more: Whole Wheat Vs. Wheat Bran
The "All-Bran challenge" or diet is an eating regimen proposed by Kellogg's to improve digestion, decrease bloating and speed up stool transit time in the digestive tract. The length of the challenge varies depending on country but tends to last for five or seven days.
The only dietary change Kellogg's suggests during the challenge is eating a serving of one of their All-Bran cereals for breakfast. Kellogg's also offers breakfast, lunch, dinner and snack recipes that use their All-Bran cereals as an ingredient to help increase your fiber intake.
But there are many ways to increase your fiber intake — not just by adding all-bran cereals and baked goods to your diet. You can also eat fresh fruit, vegetables and legumes, or take fiber supplements such as psyllium husk, polycarbophil and methylcellulose.
Risks of All-Bran Diet
Though most Americans do not get the recommended daily amount of fiber according to the FDA, you can have too much. You might experience gas, bloating or constipation on an all-bran diet because your body needs time to get used to breaking down the increased fiber load.
Read more: Wheat Bran Vs. Oat Bran
Your digestive issues might go away on their own once the bacteria in your digestive tract have had time to adjust. If you still experience digestive discomfort after a few weeks on an all-bran diet, consider decreasing the amount of fiber you consume. Calculate how much you are taking in, and if it exceeds the recommended daily allowance for your sex and age range, decrease the amount slowly until your symptoms go away.
Too much fiber can also interfere with absorption of nutrients such as iron, magnesium, calcium, copper and zinc. You are at a higher risk of malabsorption if you take fiber supplements as opposed to eating fibrous foods, many of which are mineral-rich. Play it safe and consume fiber in moderation — try not to eat more than 70 grams per day.
- Harvard Health Publishing: "Making One Change — Getting More Fiber — Can Help With Weight Loss"
- Grains and Legumes Nutrition Council: "Types of Grains"
- Harvard T.H. Chan School of Public Health: "Whole Grains"
- MedlinePlus: "Fiber"
- World Journal of Gastroenterology: "Stopping or Reducing Dietary Fiber Intake Reduces Constipation and Its Associated Symptoms"
- USDA: "Dietary Guidelines for Americans, 2015-2020: Appendix 7. Nutritional Goals for Age-Sex Groups Based on Dietary Reference Intakes and Dietary Guidelines Recommendations"
- Duke Student Health Nutrition Services: "Fiber: How Much Is Too Much"
- Harvard T.H. Chan School of Public Health: "Carbohydrates"
- Kellogg's: "Our Best Days Are Yours"
- Journal of the American Association of Nurse Practitioners: "Fiber Supplements and Clinically Proven Health Benefits: How to Recognize and Recommend an Effective Fiber Therapy"
- Journal of Chiropractic Medicine: "Dietary Fiber Is Beneficial for the Prevention of Cardiovascular Disease: An Umbrella Review of Meta-Analyses"