Think Fibre Is Only Good For One Thing? Think Again

While fibre and bowel regularity have always gone hand in hand, the plant-based carbohydrate does a lot more than just grease the wheels of your digestive system. Research shows that regular consumption is linked to improved weight management and mood, as well as a reduced risk of mortality from heart disease, stroke and all cancers.

“I’ve been talking about fibre since the dawn of time,” says Mairlyn Smith,  a Toronto-based home economist, cookbook author and Second City alum. Whether through her cookbooks or on her wildly popular Instagram page, the self-proclaimed Queen of Fibre has made it her mission to inspire people to ramp up their ingestion of the health-supporting nutrient. (She’s also been walking the, er, fibre-friendly walk. In March 2023, she went viral for her “Fartwalks,” post-dinner strolls in which she and her hubby stroll off their fibre-rich meals ). Here’s what she wants you to know.

Fibre is the least sexy nutrient, but it’s got staying power

Fibre is a carbohydrate found in a vast variety of whole foods, from fruit and vegetables to legumes, nuts and seeds, and whole grains. There are two kinds of fibre—soluble and insoluble—and both offer unique health benefits. 

Soluble fibre foods (which include oatmeal, citrus, strawberries and dried beans) are correlated with maintaining a healthy blood sugar. Insoluble fibre foods (such as whole-wheat flour, nuts and seeds, potatoes and green beans) help you feel fuller faster. Most high-fibre foods contain a mix of insoluble and soluble fibres, which means they offer a lot of bang for their buck. The other bonus: High-fibre foods are also packed with other good-for-you vitamins and minerals. 

“The missing link in aging wonderfully is a diet high in fibre,” says Smith. All of this said, she concedes that fibre has a bit of a... reputational issue. “I think we’re all really embarrassed about bowel movements and farting and what happens if you have too much fibre.” 

Fibre is ridiculously good for you in almost every way

Smith grew up in Vancouver, filling her plate with fibre-rich vegetables from her parents’ garden. That early emphasis on the benefits of eating a largely plant-based diet became a lifelong passion—in 1976 she graduated with a degree in home economics from the University of British Columbia. It was while researching her eighth cookbook, 2019’s Peace, Love and Fibre, that Smith became ever more convinced that fibre was an essential component in supporting longevity. “All these foods that were apparently great at reducing the risk for certain diseases had one thing in common, and that was that they all contained fibre,” she says. 

Smith isn’t just blowing hot air. Research consistently shows that fibre has a broad spectrum of benefits. A diet high in fibre is typically more filling, which means you might not need to eat as much. Fibre also feeds the gut microbiome, and a healthy microbiome has been associated with improved mental health. Not only is fibre heart- and gut-friendly, but it also can help prevent the development of illnesses like type-2 diabetes. Most impressive of all, a diet high in fibre is associated with a lower risk of mortality overall from heart disease, stroke and all cancers. 

The bad news: you’re not eating enough of it

According to Health Canada, women need at least  25 grams of fibre a day, but despite these recommendations a fraction of people manage to get that. (Most Canadians only average around 14 grams a day.)

That lack of fibre in the average person’s diet makes it a nutrient of concern, says Smith—but it’s never too late to put eating more fibre at the top of your to-do list. 

“The sooner you start having that balanced diet that includes lots of fibre-rich foods, the better shot you have at aging wonderfully,” says Smith.

Take it slow and low 

You’re probably not getting enough daily fibre in your diet, but avoid overcorrection “I just had a breakfast of bran buds, ground flaxseed, hemp hearts, berries and soy milk that would blow the ass off the average person,” she jokes.  To avoid rocket launching yourself out of your work chair after overdoing it with the flax, she tells people to start “slow and low.” 

“If you try to get the recommended fibre intake for your age group on day one, you won't leave your house. Your gut is going to go crazy.”

Instead, says Smith, tackle your fibre deficit in stages. Start easy: add a daily apple to your diet for three to five extra grams of fibre. After that, add an orange into the mix, for three additional grams. Then start adding even more fibre-rich fare to your grocery cart, including whole grains like whole wheat, barley and oats as well as seeds, nuts, beans, whole grains and an abundance of fruits and veggies.

Smith is a big fan of ground flaxseed. “A teaspoon added to your cereal or smoothie is an easy little addition,” she says. You can eventually build up to a tablespoon (which contains about 2 grams of fibre) or even two as you continue folding in nuts, legumes and more whole grains into your diet.

Don’t forget to fill your water bottle

If you’re upping your fibre intake you need to ensure you’re drinking more water, too.  Fibre absorbs water as you digest and if you’re dehydrated or not drinking enough H20—think six to eight glasses a day—it can affect your digestion. “If you don’t have enough water in your body, you’ll become constipated," cautions Smith. “So, you need to do those two things at the same time.”

Don’t fear the flatulence 

“There’s a lot of women who would rather implode than fart,” says Smith. But don’t let a fear of backfiring keep you on the wrong side of your fibre intake. While Smith has gone viral for her post-dinner firecrackers, her walks are rooted in real health benefits. Walking after meals is not only a digestive aid, but research also suggests that as little as five minutes of light walking after meals can help regulate blood sugar levels. 

Consider the farts the soundtrack to these benefits. And letting loose outdoors has an obvious upside, as Smith has discovered. “I thought, this is excellent because it’s not in the house.”

Want to incorporate more flaxseed into your diet? Try this delicious flax muffins recipe.