As a modern day, health conscious citizen, you might often come across the term "fiber". Fibers would obviously appear in the list of food choices prepared by a dietician. High fiber foods form an essential part of a weight-watcher's diet. Fibers are known for their actions against health conditions like diabetes, constipation and heart related issues.
Fiber can be classified as soluble or insoluble. Soluble as well as insoluble fibers cannot be absorbed in the blood stream as they remain undigested in the gut. The roles or functions of each of these fibers are equally important and so it is really difficult to place one type above the other! Both these types of fibers help you in feeling full for a longer period of time. Fibers reduce your appetite and this has an effect on your weight loss or weight maintenance process.
Let's check out the basic features of each type of fiber:
Soluble Fiber: Sources and Functions
Soluble fiber is a type of fiber that forms a gel-like consistency when combined with water in the digestive tract.
Sources of Soluble Fiber:
- The fruit sources include apples, pears, guava, plums, berries, banana and prune juice.
- Cereals like oats , barley, rye and chia.
- Vegetables like broccoli, artichokes, carrots and roots like sweet potato and onions.
- Legumes like soybean, peas, beans and lupines.
- Psyllium seed husk.
Functions of Soluble Fiber:
- During digestion, soluble fiber forms a gel with the available water and traps the carbohydrates, leading to slow release of glucose in the blood. This further slows down the absorption of glucose and helps to improve diabetic conditions. This way, it regularizes the blood sugar level and helps in avoiding sugar spikes in blood after the intake of food. According to a study published in the Journal of the American Dietetic Association, the soluble fibers present in oats can reduce the levels of blood insulin, blood glucose and cholesterol in individuals with non-insulin dependent diabetes.
- Soluble fiber forms a gel with water in the digestive tract. This helps slow down the digestion and delays the emptying of your stomach, making you feel full. This helps in controlling your weight.
- Soluble fiber can help lower total cholesterol as well as LDL ("bad") cholesterol by interfering with the absorption of dietary cholesterol. Soluble fibers binds to bile acids (necessary for fat digestion) made by the liver from cholesterol and carry it to intestine for defecation. As a result, the liver must use additional body stores of cholesterol to manufacture new bile acids. This way soluble fibers help reduce the risk of heart disease. A study conducted by Boston researchers suggests that the increasing the consumption of dietary fiber can reduce the risk of heart attacks.
- Soluble fiber gets fermented by the bacteria in the intestine to produce a short-chain fatty acid called butyric acid. This fatty acids helps keep the colon healthy and intact by maintaining a healthy pH in the intestine. This improves the absorption of certain minerals and helps prevent colon cancer.
- A study conducted by the researchers at the University of Illinois, suggests that the soluble fiber present in oats, apples and nuts, can decrease inflammations caused by obesity-related health conditions, such as diabetes and heart disease. The same study claims that soluble fibers have the ability to boost the immune system.
Insoluble Fiber: Sources and Functions
This type of fiber does not ferment in the intestine, but it absorbs water and has a bulking action, which helps in the process of waste removal or defecation.
Sources of Insoluble Fiber:
- The vegetable sources include beans, zucchini, cucumber, carrot, celery, leafy greens, cauliflower and cabbage.
- Whole grains / brans of cereals like wheat and corn.
- Skins of vegetables like potatoes and tomatoes.
- Nuts and seeds.
- Flax seed / Sprouted Fenugreek seeds.
- Lignans.
Functions of Insoluble Fiber:
- It helps in speeding the passage of food from the digestive tract, thus removing the toxic waste through colon in less time. However, this decreases the absorption of some nutrients as they lack the time to come into contact with the appropriate part of the intestines.
- It helps in building bulk and in the formation of stools. This helps prevent or relieve constipation.
- As per the reports published by the American Heart Association, insoluble fibers can bring down the risk of cardiovascular diseases. A study published in the American Journal of Clinical Nutrition in October 2010, suggests that three servings of whole grain foods per day can reduce blood pressure in middle-aged individuals and this in turn, can reduce the probability of occurance of cardiovascular diseases in this group by more than 15 percent.
- It helps to create a regularity in defecation, which is associated with a decreased risk for colon cancer and hemorrhoids.
The preferred intake of fiber should be around 25 grams per day. You cannot draw any comparison between these two types of fibers because each has its individual characteristics and distinct roles. You need to include the sources of both these types of fibers in your diet to sustain a healthy life. By focusing on eating a healthy diet rich in fruits, vegetables, whole grains, legumes, nuts, and seeds, you can be sure that you are getting both types of fiber.
