If you eat a typical North American diet, then there is a good chance you are not getting enough fibre. There is also a good chance you have not been getting enough for much of your life. In this article I will discuss the different types of fibre, the benefits of each, the best food choices for increasing your fibre intake and when to know if you should avoid some types of fibre.
(note that as a Canadian, I use the spelling fibre rather than the US spelling of fiber. Either way the same advice about fibre applies.)
What is dietary fibre?
Dietary fibre is the roughage or bulk found in fruits, vegetables, whole grains and legumes. It is an undigestible carbohydrate. But just because it is undigestible, doesn’t mean it doesn’t have benefits. Fibre helps to:
- Reduce risk of cardiovascular disease
- Reduce risk of type 2 diabetes
- Increase satiety
- Improve bowel function
- Lose weight
There are two types of dietary fibre – soluble and insoluble. Both have uses in our diets.
Soluble fibre is fibre that is soluble in water. It is gel like and not like a bran. The gel like substance in cooked oatmeal is an example. Soluble fibre helps to improve cholesterol levels and helps to keep blood sugar levels balanced. Soluble fibre is also a prebiotic (a food that helps probiotics, the good bacteria). This is good for digestive health. Foods that contain soluble fibre include:
- Legumes such as black beans, lentils
- Some Fruits
- Some Vegetables
- Nuts and seeds
Insoluble fibre does not dissolve in water. It is what we normally think of when we think of fibre (wheat bran). Insoluble fibre helps to make us feel more full and it adds bulk to help move food through our digestive tracks. Foods that contain insoluble fibre include:
- Whole grains like brown rice, wheat, barley
- Some fruits and vegetables
- Nuts and seeds
How can you add more fibre to your diet?
Women should aim for 30 grams of fibre per day. Men should aim for 40 grams. You may be tempted to add fibre by taking a supplement or by eating a bran cereal but neither of these is the best option. The best way to increase fibre intake is by eating a variety of plants. Plant foods contain fibre in the form it was meant to be found and they also contain vitamins, minerals, carbohydrates and even protein.
Eating a variety of foods from the examples above will help to increase fibre levels. Here are some ideas:
- Add chickpeas or lentils to your salads and soups
- Add black beans to your chilli
- Choose whole grains
- Eat steel cut oats for breakfast
- Snack on raw nuts or fruit
- Make sure you are eating vegetables as much as possible
Try to limit processed foods even if they claim to be high in fibre. Also limit fibre supplements. Neither of these have the vitamins and minerals that you find in whole foods like vegetables or whole grains.
Things to watch for
If you are trying to increase the fibre in your diet, then there are a few things to be careful with.
Adding fibre too quickly to a low fibre diet can cause gas and stomach distress. This often occurs when people add fibre supplements to their diets or if you eat beans when you don’t usually eat them. Add much fibre rich foods slowly to your diet.
If you are on a low FODMAP diet you will need to be careful choosing the grains, vegetables and legumes you eat. Within the two groups of fibre there are several different kinds of fibre and some people are intolerant to some of these types of fibre.
By helping to quickly move foods through your digestive system, eating more fibre decreases the absorption of some minerals. If your diet is high in fruits and vegetables this should not be a problem and seems to only occur when fibre intake is very high.
If you are not getting enough fibre, then adding fibre to your diet will likely improve your health. It can even help you to lose weight. Start by adding a little and increase the fibre rich foods slowly.