Fiber: Friend or Foe?

Fiber is a component of our food that is constituted of indigestible matter from plants. As such, it is found primarily in fruit, vegetables, cereals and seeds (raspberries, broccoli, oats and lentils are all good examples of high-fiber foods). But is it good or bad for you? As it is generally found with nutritional advice, the key to an optimal diet and a healthy lifestyle is balance. Consuming the right amount of fiber can bring a number of benefits to your health, such as helping to prevent cardiovascular disease through treating high blood pressure (hypertension) and lowering cholesterol, assisting diabetics in the control of blood sugar levels and even reducing the risk of colon cancer (or bowel cancer). But can you eat too much fiber? The simple answer is yes. While such benefits emphasise that it should be a crucial part of your diet, eating too much fiber can cause a variety of unpleasant side effects. This article will inform you of the correct amount of fiber you should have in your diet, as well as explaining to you the symptoms of its overconsumption so that you may recognise what happens when you eat too much fiber. 

First Things First, How Much Fiber Do You Need a Day?

As previously mentioned, eating the right amount of fiber will ensure that you gain the health benefits that it can bring without experiencing the negative symptoms that may occur when you eat too much fiber. Guidelines issued by the Institute of Medicine state that men should consume between 30 and 38 grams a day, while women between the ages of 18 and 50 years old should eat 25 grams a day and females aged 51 and over are to eat 21 grams. These different requirements between groups can largely be attributed to the differences in size between men and women, and so it is more specifically advised that the amount of fiber you eat should correlate with the amount of calories you consume on a daily basis.

The USDA’s recommendation that you should ingest 14 grams of fiber for every 1,000 calories consumed is helpful, as it considers the requirements of each individual; for example, if you are a very active person who has a high-calorie diet, you will need a greater amount of fiber than an individual who is trying to lose weight on a low-calorie diet. Surprisingly, the average person consumes only 15 grams of fiber a day, irrespective of the amount of calories eaten, which suggests that the majority of people are not getting enough of it in their diet.

How to Tell If You’re Having Too Much Fiber

It is important to be aware of what happens when you eat too much fiber as you try to increase your own intake of it to meet the suggested guidelines. There are a number of symptoms which can indicate that you have consumed too much fiber, and these may include flatulence and bloating, loose stools, constipation, dehydration and weight gain.

1. Flatulence and Bloating

An overconsumption of fiber can make you flatulent and feel bloated. This occurs when insoluble fibers, those which do not dissolve in water, pass through your digestive system, absorbing water as it moves. While this type of fiber is beneficial for its treatment and prevention of constipation, eating too much of it will make you gassy and bloated. Foods which have high amounts of insoluble fiber and can, therefore, make you experience these issues include beans, whole-wheat products and certain vegetables (Brussels sprouts, cabbage and broccoli in particular). Avoid eating large quantities of these foods if you find yourself feeling flatulent and bloated.

2. Loose Stools

While the correct intake of fiber will ensure that your body maintains regular and proper bowel movements, an abundance of it can cause you to have loose stools and, in worse cases, diarrhoea. This can be linked to the indigestible nature of fiber; if a food contains too much fiber, a significant percentage of what has been eaten will pass through your digestive system without being properly digested, and, as a result, your stools may be loose. To prevent this from happening, try to eat a balanced meal which contains the appropriate amount of fiber by eating a source of protein that is not simultaneously a source of fiber, for this will allow your digestive system to break down the majority of food that passes through it.

3. Constipation

Overconsumption of insoluble fiber can lead to constipation. While this seems contradictory as fiber is shown to be an effective laxative, this can occur when insoluble fiber absorbs water as it passes through your body, swelling in size, making your stools larger than normal and then struggling to move easily. Increasing the amount of water you drink, as well as lowering your intake of insoluble fiber, can prevent this problem.

4. Dehydration

Because insoluble fiber absorbs water inside your body and removes it from your system through defecation, you may find yourself to be dehydrated if you have eaten too much fiber. It is useful to distinguish whether your dehydration is a symptom of this, or rather more simply due to an inadequate intake of water. Women and men are advised to drink between 1.6 and 2 litres of water respectively on a daily basis, and you should increase this amount if you have a high-fiber diet. If you drink a lot of water and are still experiencing dehydration, you should find out your fiber intake and lower it if necessary.

5. Weight Gain

Although explanations for it are not entirely clear, it has been reported that you may gain weight when you have high amounts of fiber in your diet. It is possible that the water absorbed by insoluble fiber and the increased amount you drink to replace lost fluids leads to weight gain as your body retains a greater amount of water. Equally, fiber is a carbohydrate which is a source of energy that is converted to fat if unused by your body, which may help to explain why some people have noticed weight gain when eating too much fiber.