You’ve probably heard of fiber and all of its high praises. In case you missed it, fiber has it all. It’s low calorie, packed with health benefits and fairly accessible. It has scientists raving about its ability to aid with weight loss, lower cholesterol, benefit digestive health, promote a healthy heart, stabilize blood sugar, boost immunity and even lower prevent cancers.
But if you’ve made it to this post, you’re likely wondering how fiber affects your digestive health, and more importantly, your poops. While science claims that fiber can improve digestion, does it affect how much you go? Here’s the deal on how fiber affects your bowels and how much you need to be eating to see these benefits.
Fiber is a type of carbohydrate that’s found in all plant foods, including whole grains, legumes, nuts, seeds and of course – fruits and vegetables. It is only found in plant-foods, so don’t expect to find it in a glass of milk, or a chicken wing. That’s because fiber is actually defined as the indigestible part of a plant – which is attributed to the plant's structure. It’s found in the cell wall of every plant. The structured plant wall remains undigested throughout our stomach and small intestine, meaning it passes into our large intestine in its original, undigested state. How it’s handled in the large intestine depends on the type of fiber you eat.
Fiber comes in two distinct forms: soluble and insoluble. While certain plants might be higher in one or the other, most contain a good mix of the two.
Soluble fiber dissolves in water and swells up to make a gel-like substance. Think chia pudding! You’ll find these fibers nested in most fruits, oats, barley, legumes, peas, beans, and vegetables like broccoli, carrots and root vegetables. These fibers act the same in our digestive system – they retain water and form a gel, which slows digestion. They aren’t digested until they reach the large intestine, where they are fermented by the bacteria in our gut into gases and energy.
Insoluble fiber doesn’t dissolve in water and isn’t typically as fermentable by gut bacteria. Because of this, they remain intact throughout our digestive system and help to “bulk” up your stool, giving “bulking” a whole other meaning! Insoluble fiber can be found in corn, potatoes, the skins of most tree fruits (like apples, pears, bananas), green vegetables such as zucchini, green beans and celery, cauliflower, kiwi and tomatoes. These fibers help to accelerate the movement of food through the digestive tract and allow for softer, more “regular” poops.
As you can see, each fiber has its own benefits, but like any good duo, they work best together! These fibers work together to keep things movin’ and groovin’. Soluble fiber 🤝 insoluble fiber.
In case you missed it, we need fiber in our diets for more than a few good reasons. One of the most important being, the pooping aspect, obviously 😉. Eating enough fiber is very important for having regular bowel movements and optimizing digestive health. Simply said, fiber can help you have a good ole’ normal poop.
Fiber is great for maintaining bowel movements, or as the commercials like to say, “keeping you regular”. Soluble fiber absorbs water and softens stools. Soft stools are easier to pass and can prevent constipation. Insoluble fibers “bulk up” your poop, which prevents loose poops and keeps things moving. Together, they keep things smooth and regular.
Beyond these lovely pooping benefits, eating a high fiber diet can also help to prevent certain digestive disorders, such as hemorrhoids and diverticulitis. Studies have also shown that a high fiber diet decreases the risk of colorectal cancer! It is clear that fiber, in all of its forms, is essential for a healthy digestive tract, and recent research shows that a significant part of this benefit is due to microbes in our gut.
Many soluble fibers, and some insoluble fibers, are fermentable and act as an important energy source for our gut microbiota. These fermentable fibers are known as “prebiotics,” they act as a food source for the “good microbes” in your gut, promoting growth and activity. Your gut is a key indicator of health, so it’s likely that many of the benefits of fiber are related back to its effects on gut health!
The Canadian guidelines for fiber state that adult women need 25 grams of fiber per day and men need about 38g of fiber per day. Something to note is that these guidelines might not be the best fit for you. Things such as physical activity, age, gender and medical conditions can affect your fiber needs. So, it’s always a good idea to check in with a healthcare professional before adding a crazy amount of fiber in your diet. At the end of the day, we’re all magically unique and so are our fiber needs!
As some of you may already know, too little fiber can cause digestive issues, like constipation. Not getting enough fiber is generally just less than ideal, because we know that fiber comes from plants, and plant foods provide a lot of vital vitamins and minerals that keep us functioning our very best!
While we know that too little fiber is problematic, many haven’t considered the possibility that too much fiber is a problem. Some individuals who eat more than the recommended fiber intake might experience bloating, gas and abdominal pain. It’s also possible that eating too much fiber can affect your mineral levels. Fiber is a binding agent, which in part makes it beneficial – as it binds cholesterol and excretes it, but it can also bind minerals before we’ve had the chance to absorb them. However, this is unlikely and would require a lot of fiber!
That being said, eating a ton of fiber without drinking enough water can also be problematic. As we now know, soluble fiber dissolves in water, and therefore it works best when eaten with lots of water. So be sure to stay hydrated when you eat high fiber foods, this can help to prevent side effects and keep things moving.
Ah yes, the golden question that we all came here for. Sadly, there is no one right answer for this question, I know, lame, but health is complicated. The most plausible answer is that if you are not currently meeting your fiber needs (as half of Canadians are not!), then fiber can make you poop more, especially if you’re looking to relieve constipation.
But for many, fiber isn’t notorious for making you poop more, it is known to make you more regular. Regularity simply means having more consistent and predictable bowel movements. For many who struggle with disordered and irregular bowel movements, like those with IBS or chronic constipation, increasing fiber is a typical recommendation from doctors. However, it might not benefit everyone, and it is something to discuss with a healthcare professional.
In any case, take it easy as you ramp up your fiber content. Increasing fiber too quickly can bring out some pretty uncomfortable side effects, like bloating, gas and pain. So, when it comes to adding fiber, it is best to start low and go slow. And always remember to drink plenty of water!
If you’re looking to add more fiber into your diet, check out the best foods to eat when constipated or consider adding Holy Crap cereal into your diet! Holy crap cereals contain super seeds, which are loaded with a mix of soluble, insoluble and prebiotic fibers, to get your gut in the shape of its life. Never mind strength training, have you tried gut training? Now that’s a 2021 trend we can get behind!
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