High fiber foods offer an array of health benefits for everyone and are particularly important for people with type 2 diabetes.
Fiber is the term used to describe the parts of plants that can’t be broken down (digested) by the human digestive system (except for the bacteria found in the large intestine that partly digests fiber through fermentation).
Why are high fiber foods so important?
It has been discovered that fibre plays a very important role in maintaining good health and preventing disease. Modern eating habits, however, have resulted in the vast majority of people consuming a diet that is low in fiber.
This is mainly due to our consumption of highly refined and processed foods, which have had the majority of their fiber removed through the refining process.
Eating a diet that is low in fiber certainly reduces our health and increases our risk of disease. A low-fiber diet is correlated with an increased incidence of heart disease, a number of gastrointestinal diseases, and cancer, particularly of the colon and rectum.
The health and diabetic benefits of high fiber foods:
The types of high fiber foods:
Soluble fiber dissolves in water and when it is eaten in a meal it forms a gel in the stomach and slows gastric emptying (food emptying from the stomach into the intestines). It also slows the absorption of carbohydrates from the intestines. This means there will be a slow influx of glucose into the blood stream, resulting in a reduced insulin production. Therefore, soluble fiber may help to prevent and reverse diabetes.
Soluble fiber increases stool bulk slightly but not as much as insoluble fiber. It also supports the growth of normal intestinal bacteria. The bacteria causes the soluble fiber to ferment, which produces short-chain fatty acids. These short-chain fatty acids have a range of physiological health and weight-loss benefits.
One of soluble fiber’s most important functions is in the way it is able to lower cholesterol by binding to bile salts in the bloodstream so they can’t be re-absorbed into the body (cholesterol is one of the components of bile).
Here’s a list of high fiber foods that contain soluble fiber:
Most fruits and vegetables contain soluble fiber. However, their skins are composed of insoluble fiber.
Insoluble fiber, as the name suggests, does not dissolve in water but it does attract water, which means it adds more bulk to the stools and makes its passage through the intestines much faster, i.e. it decreases the gastro-intestinal transit time. This reduction in intestinal transit time helps to normalise gut function and prevent many disorders resulting from abnormal bowel function, i.e. irritable bowel syndrome and diverticulitis.
It comes from the structural components of plant cell walls and is found in fruit and vegetable skins, whole-grain products (especially wheat bran) and some seeds.
Insoluble fiber’s dilution of intestinal contents helps to minimise the impact of any cancer-causing compounds that may have been consumed, therefore reducing the risk of colon cancer.
Here’s a list of high fiber foods that contain insoluble fiber:
Myths about high fiber foods
Many people believe that high fiber foods may reduce the absorption of minerals from the intestines. In fact, fiber does not bind to minerals or vitamins and prevent their absorption into the body but rather soluble fiber, when fermented, actually improves absorption of minerals.
This results from the short-chain fatty acids that get produced by the bacteria. These fatty acids lower the pH of the intestines (increase the acidity), which improves mineral absorption. Some plant foods that prevent absorption of minerals contain ‘phytate’ and this is thought to be the cause.
Fiber intake recommendations
It is generally recommended that adults consume 20-35 grams of fiber per day and this should be a combination of both soluble and insoluble fiber.