What Does Fibre do for Digestive Health?
Navigating a healthy diet can feel like a maze. At every turn, there’s another flashing sign telling you to eat more of this and less of that. Add the constant conflicting information and it becomes even more confusing! Therefore, it’s understandable why people don’t know what or how much of certain foods and nutrients to eat. Fibre is a nutrient we often don’t get enough of. It’s a staple in a well-balanced diet, but the funny thing is your body can’t digest it. It sounds silly when you think about it – eating something your body doesn’t digest, but fibre has so many health benefits.
Fibre is one of the main reasons whole plant foods are good for you. Growing evidence shows that adequate fibre intake benefits your digestion and reduces your risk of chronic disease. Many of these benefits are mediated by your gut microbiota — the millions of bacteria that live in your digestive system. However, not all fibre is created equal. Different types have different health effects.
Fibre is split into two broad categories based on its water solubility:
- Soluble fibre: dissolves in water and can be metabolised by the “good” bacteria in the gut.
- Insoluble fibre: does not dissolve in water.
Perhaps a more helpful way to categorise fibre is as fermentable versus non-fermentable, which refers to whether friendly gut bacteria can use it or not. It is also important to keep in mind that there are many different types of fibre. Some of them have important health benefits, while others are mostly useless.
There is also a lot of overlap between soluble and insoluble fibres. Some insoluble fibres can be digested by the good bacteria in the intestine, and most foods contain both soluble and insoluble fibres.
Some types of fibre can help you lose weight by reducing your appetite. In fact, some studies show that increasing dietary fibre can cause weight loss by automatically reducing calorie intake. What happens is certain fibres soak up water in the intestine, slowing the absorption of nutrients and increasing feelings of fullness. However, this depends on the type of fibre. Some types have no effect on weight, while certain soluble fibres can have a significant effect. A good example of an effective fibre supplement for weight loss is glucomannan.
How your body uses fibre:
- It sticks to “bad” cholesterol so your body doesn’t re-absorb it.
- It helps your digestive tract stay active. It’s like a workout that keeps your digestive tract strong and healthy.
- Fibre stabilises your blood sugar levels.
- Fibre helps control weight by making you feel full for longer. This reduces the likelihood of bingeing snacks when hunger hits you like a ton of bricks.
- It assists in regular bowel movements without struggle.
How much fibre should I be getting in my diet?
- Most men under 51 should aim for 38g of fibre per day. Most women should aim for 25g of fibre per day.
- Most men aged 51 and up should aim for 30g of fibre per day. Most women 51 and up should aim for 21g per day.
Those can feel like high numbers if you don’t know where to get more fibre.
How do I know if I am getting enough fibre in my diet?
The easiest thing to do is use a food tracking app like Myfitnesspal and track your food for 1-3 days. You might be surprised at which foods give you fibre in a day. You can also use this information to make small changes to your meals and reach your fibre goals. Your diet doesn’t need to completely change overnight. Start small, end strong!
How do I add fibre into my diet?
You can get more fibre by eating certain foods. Here are some strategies to incorporate these into your diet.
1. Eat whole-food carb sources
Fibre is a type of carb found in plant-based foods. While most carbs break down into sugar, fibre stays intact as it passes through your digestive system. This contributes to helping you feel fuller for longer when eating fibre along with other carbs. It also slows the time it takes digestible carbs to be absorbed into your bloodstream, helping to regulate your blood sugar levels. Whole-food carb sources all naturally contain fibre. These include fruits, starchy vegetables, legumes, and whole grains.
2. Include vegetables in your meals, and eat them first
For a number of reasons, you should eat lots of vegetables. For one thing, they can lower your risk of several chronic diseases. Non-starchy vegetables are also particularly low in calories and high in nutrients, including fibre.
Eating your vegetables before a meal is a good strategy for eating more of them. In one study, women given salad 20 minutes before a meal ate 23% more vegetables than those served salad at the meal itself. Eating salad or vegetable soup before a meal has also been linked to eating fewer calories during a meal.
3. Eat popcorn
Popcorn is one of the best snack foods around. That’s because it’s actually a whole grain, delivering 4 grams of fibre per ounce (28 grams). That’s 3 cups of air-popped popcorn. For the lowest calorie popcorn, air pop it either in a brown paper bag in the microwave or in an air popper. For added flavour without added fat or calories, sprinkle it with cinnamon, or if you like things spicy, a little cayenne pepper.
4. Snack on fruit
Individual pieces of fruit, such as an apple or pear, make great snacks because they’re tasty, don’t require a lot of prep, and portable. All fruit delivers fibre, although some have significantly more than others. For instance, one small pear has almost 5 grams of fibre, whereas a cup of watermelon has less than 1 gram. Berries and apples are other high fibre fruits. The fibre from fruit can improve fullness, especially when paired with food that contains fat and protein, such as nut butter or cheese.
5. Choose whole grains over refined grains
Whole grains are minimally processed, leaving the whole grain intact. In contrast, refined grains have been stripped of their vitamin-containing germ and fibre-rich bran. This makes the grain last longer but also takes away the most nutritious parts, leaving only a fast-absorbing carb.
Try replacing at least half of the refined grains in your diet with whole grain versions. Some whole grains to try include:
- Brown rice
- Bulgur wheat
- wheat berries
6. Take a fibre supplement
It’s best to get your nutrition, including fibre, from food. However if your fibre intake is low and you are struggling to make dietary changes, you might consider taking a supplement. This is best done under consultation with your doctor.
A few types of supplements have research to back them up:
- Guar fibre: As a supplement, guar fibre may improve fullness and lower your overall calorie intake. It’s also used in processed foods to improve texture.
- Psyllium: This is the key ingredient in Metamucil, a popular fibre supplement used for constipation. In one study, psyllium was also shown to decrease hunger between meals.
- Glucomannan: This fibre is added to some low fat dairy products to improve texture, and it’s the main ingredient in no-calorie shirataki noodles. As a supplement, it increases fullness and reduces appetite.
- B-glucans: This type of fibre is found in oats and barley. It’s fermented in the gut and acts as a prebiotic to support the healthy microorganisms that live there.
It’s important to note that supplements have two main drawbacks. First, they can cause stomach discomfort and bloating. To reduce this, introduce a fibre supplement gradually and drink plenty of water. Second, these supplements can interfere with the absorption of certain medications. So, if you’re currently taking any medications, definitely speak to a healthcare professional before taking a fibre supplement.
Overall, fibre is a cornerstone of a healthy diet. If you assess and notice that you’re not getting enough fibre, then focus on one strategy to incorporate fibre into your diet and build from there!
This article was written by Abraham Anjarkouchian, MSc, RD at The Cohen Clinic