- Fibers are generally classified as soluble and insoluble dietary fibers.
- The ideal daily intake of dietary fibers for adult men and adult women is 38g and 25g, respectively.
- Along with constipation, low fiber consumption can also cause elevation of LDL cholesterol, and obesity.
- Although high fiber diet proves very beneficial for health, too much consumption can also have health disadvantages.
- If we are talking about regulating the metabolic functions of the body, like lowering bad cholesterol, nothing is better than soluble dietary fibers.
Dietary fiber is an important nutrient in every individual’s diet. It is basically the edible portion of plants which our body cannot digest but rather pass it through the digestive system mostly intact and unbroken.
Soluble Fiber vs. Insoluble Fiber
Fibers are generally classified as soluble and insoluble dietary fibers.
Soluble fibers dissolve in water to develop a gel-like consistency and have various beneficial metabolic effects such as reducing cholesterol and blood sugar levels.
Insoluble fibers, such as cellulose, do not absorb water and mostly act as a bulking agent for stool.
Although indigestible, dietary fibers are very much necessary for our body because of their various health-regulatory effects.
“According to the Institute of Medicine Food Nutrition Board, the ideal intake of dietary fibers for adult men and adult women is 38g/day and 25g/day, respectively.”
Fibers have various advantages if taken as per recommendations. Dietary fiber plays an important role in maintaining our bowel health.
It normalizes the peristaltic movements and also reduces the risks of hemorrhoids and colorectal cancer.
Moreover, it helps in lowering serum cholesterol and blood glucose levels; therefore, it is very beneficial for the patients of cardiovascular diseases and diabetes.
It is also very helpful for weight management purposes as it creates a sense of fullness.
What happens when you do not consume enough fiber?
Despite the availability of various fiber-rich food items, many people do not manage to achieve their daily ideal fiber requirements.
Low consumption of dietary fibers can lead to several health-related issues.
In a research study conducted among preschool children, it was established that a low fiber diet caused constipation among children who had a very low dietary fiber intake.
“Along with constipation, low fiber consumption can also cause obesity and an elevated LDL cholesterol level”
Chronic low fiber intake may also lead to severe disorders such as irritable bowel syndrome and colorectal cancers.
Excessive fiber intake
“Although a high fiber diet proves very beneficial for the health, too much consumption is also not good.”
Excessive fiber intake above the ideal average daily requirement can have various health disadvantages.
According to a research study, an increased intake of dietary fiber (>50g/day of dietary fibers compared to 25g/day) did not have a significant impact on rates of calcium absorption and content of phosphorus and magnesium among type 2 diabetes patients.
However, too much fiber consumption can cause diarrhea, flatulence, bloating, reduction of good cholesterol (HDL), and sometimes constipation as well.
Food items rich in Dietary Fiber
There are various food products that can help us fulfill our daily fiber requirements.
Among the best resources are beans, avocado, lentils, peas, vegetables and citrus fruits. Each source has different proportions of fibers.
Fiber types, their sources and pros and cons.
Pectin
Pectin is usually a soluble fiber however some types are insoluble.
This type is usually found in fruits, berries and seeds.
They are known to reduce blood cholesterol but stomach cramps, flatulence, diarrhea can occur if consumed excessively.
Cellulose, Hemicellulose
These types of fiber are insoluble and can alleviate constipation, help in weight management and decrease the incidence of diverticulitis.
Disadvantages include gas, diarrhea, bloating and constipation if consumed excessively.
Good sources are whole wheat, bran, grains and brown rice.
Inulin
A soluble form of fiber. It is usually known for improving the immune function but can cause cramps, gas, diarrhea, and constipation if consumed excessively.
Inulin can be found in good quantities in onions, beets and garlic.
Lignin
An insoluble type of fiber that is best found in vegetables, rye and flax.
Lignin has many health benefits for the heart and for the immune system.
It can also cause constipation and can worsen celiac disease if consumed excessively.
Beta-Glucans
Commonly found in beans, barley, fruits and oats.
This type of fiber is soluble and reduces LDL, decreases risk of CHD and type 2 diabetes but may cause nausea, vomiting, diarrhea if consumed excessively.
Wheat Dextrin
A soluble form of fiber that is usually found in wheat starch.
It decreases LDL and blood glucose levels however, it causes flatulence, abdominal pain and diarrhea if consumed excessively.
Psyllium
Seeds and husks of plant are the best sources of this soluble fiber.
It reduces constipation and lowers cholesterol.
Common disadvantages are skin rash, itching, abdominal pain, nausea, vomiting if consumed excessively.
Resistant Starch
A soluble fiber that has advantages in weight management, in controlling blood glucose and in enhancing insulin sensitivity.
It can be found in legumes and oatmeals.
However it may worsen celiac disease and can cause constipation if consumed excessively.
Which dietary fiber is best for me?
Different types of dietary fibers have different functions. Which fiber is better for you depends upon the specific functions of the fiber source.
Soluble Fibers
If we are talking about regulating the metabolic functions of the body, like lowering bad cholesterol…etc, nothing is better than soluble dietary fibers.
It is also proven by a research study that diets rich in soluble fiber are more effective in lowering LDL cholesterol and apolipoprotein B levels compared to diets containing greater amount of insoluble fibers.
Insoluble Fibers
On the other hand, when we talk about the bulking effect to stool, and bowel movements regulation, insoluble fiber is better.
In a research study, insoluble dietary fiber components better contributed to stool bulking and normal digestive functions when compared to soluble fibers.
Dietary Fiber as part of your complete diet
It is advised to take 6 to 8 grams of soluble fibers daily i.e. 25% of the total ideal daily dietary fiber requirement.
To put the above discussion in a nutshell, dietary fiber is an integral component of our diet and therefore it is necessary to fulfil our ideal average daily requirement.
Too low and too high fiber consumption, both have harmful effects.
A healthy diet must contain adequate proportions of both soluble and insoluble types of dietary fibers.
