Fiber is a part of the food that we eat, and our bodies don’t have the ability to digest it. You can find fiber in a variety of foods. It’s a large part of fruits and vegetables, in addition to grains, nuts and seeds.
When you consume these foods and the body uses up what it can, the fiber will then be removed through the colon in the form of fecal matter. In other words, fiber can make you poop, which can be good for many reasons, such as helping with occasional constipation.
When people don’t consume enough fiber, this can result in less frequent stools that are hard to pass (constipation). Too much fiber can have the opposite effect and keep your stools from being firm enough (diarrhea).
Fiber has a very profound importance in our daily diet, but you may be wondering how much you should actually be consuming each day. I’m about to talk with you about the appropriate amount of fiber to add to your diet, the different types of fiber that exist (soluble vs. insoluble) as well as some ways that you can increase your fiber intake. Our team also had the pleasure of asking another expert, Nichole Dandrea, MS, RDN, to expand on some of the questions around daily fiber intake. After you’re done reading, you’ll be well on your way to more regular and productive bowel movements.
Your Guide to Daily Fiber Intake
Most people are aware of the fact that they should be including fiber in their daily diet but knowing how much to consume is another concept altogether. Here is information to help guide you towards a proper daily fiber intake.
Types of Fiber and Where to Find Them
Let’s take a look at the two main types of fiber (soluble and insoluble), as well as some of the other forms of fiber that you can consume for optimal gut health.
Soluble Vs Insoluble Fiber
When we talk about solubility of fiber, we’re referring to fiber’s ability to dissolve in water. When you have soluble fiber, it will blend together with water that is present in your GI tract. This forms a gel-like substance that makes it easier for stools to pass through your colon. This type of fiber can also prevent dramatic spikes in your blood sugar. Examples of soluble fiber include pectin, psyllium husk and natural gums. As a dietitian, I'm constantly looking at benefits of certain foods and ingredients. That said, there are some strong health benefits of psyllium husk that could get your wheels turning.
Insoluble fiber doesn’t have the ability to blend together with water, so it will pass through your colon close to its original composition. This is what would add more bulk to your stools, so things pass through quickly. That’s why if you eat too much insoluble fiber, you can end up with a bout of diarrhea. Examples of insoluble fibers include cellulose and lignin.
Fermentable Fiber
Fermentable fiber is able to be digested by the beneficial bacteria in your gut and used by the body as fuel. We have over 100 trillion bacteria in our gut at any given moment, and it’s ideal that we maintain these levels in order to maintain optimal health. We can benefit from the consumption of fermentable fiber by experiencing better weight management, balanced blood sugar levels and improved cognitive function. Fermentable fibers like beta-glucans, beans, inulin and guar gum will actually increase the number of beneficial bacteria in the gut. The only downside to fermentable fiber is that it can make you gassy when it is being broken down in the gut. Eating too much can be rather uncomfortable.
Viscous Fiber
Viscous fiber sources will blend with water in the intestines and form a very thick gel.; much thicker than soluble fiber alone. This substance will sit in the gut, causing a decrease in the speed of digestion and nutrient absorption. This means you’ll feel full longer, which is why viscous fiber is an important part of weight loss. It curbs your appetite. Some examples of viscous fiber include pectin, legumes, oats, flax, guar gum and psyllium.
Resistant Starch
The main type of carbohydrate that we consume each day is considered starches. These are longer chains of glucose molecules that are commonly found in things like potatoes, legumes, nuts, oats and grains like white rice. There are certain resistant starches that don’t break down during digestion, so they pass through the digestive tract seemingly unchanged. There are some distinct health benefits that come from resistant starches. For example, they lower blood sugar levels, reduce your appetite and improve your digestive health.
How Much Fiber Should You Have Per Day?
It’s recommended that you consume 28 grams of fiber per day, based on the typical 2000 calorie diet, according to the Food and Drug Administration (1). Depending on your age and gender, the amount may be a little bit different. Women under the age of 50 should be consuming between 25 and 28 grams of fiber each day, with that amount decreasing to 22 grams over the age of 50. Men under the age of 50 should be eating between 35 and 38 grams of fiber per day, with 28 grams of fiber being the recommendation over the age of 50. Children’s recommendations vary quite a bit, as their consumption will be based on their size and age. Between 14 and 31 grams per day is the FDA’s recommendation. Mayo Clinic also recommends very similar numbers (2).
I wanted to dive a little deeper and ask another Registered Dietitian to see what she had to say about how much fiber is recommended per day. So I reached out to Nichole Dandrea, a Registered Dietitian Nutritionist, author of The Fiber Effect: Stop Counting Calories and Start Counting Fiber for Better Health. She also runs Purely Planted, a plant-based wellness website that aims to help people Go Wellness!
Here's what Nichole had to say:
“More than 95% of Americans don’t get enough dietary fiber. In fact, most get less than 15 grams of fiber a day when the recommendation for individuals under 50 years of age is a minimum of 25 grams a day for women and 38 grams a day for men. Those are minimum recommendations based on evidence that supports consuming fiber for heart health. Some experts recommend at least 40 grams a day for overall optimal health.”
How Much Fiber Is Recommended Per Day to Lose Weight?
As you can probably imagine, I get this question all the time as a dietitian. Harvard Health produced an article about fiber and weight loss (3) citing an Annals of Internal Medicine study that found that eating just 30 grams of fiber each day can help you lose weight. It was a randomized trial with 240 participants (adults) and they also found that eating 30 grams of fiber per day can help lower your blood pressure and improve your body's response to insulin. The primary outcome was weight change at 12 months. So, this isn't a quick weight loss strategy, but it does work if you stay consistent with your daily fiber intake.
I love Harvard Health, and I think they're a great source of information, but why not get another expert's advice on how much fiber you need to potentially lose weight. Nichole Dandrea's answer had very similar numbers, which is great to see:
“Aim for 30 grams of fiber a day for weight management. One study (4) showed that 30 grams of fiber a day may lead to weight loss while another study (5) showed at least 28 grams a day led to weight loss. Getting 30 grams a day can be doable with simple substitutions like swapping out white bread, pasta, and rice for whole grain bread, pasta, and brown rice. Adding plant-based foods to what you're already eating can also boost fiber intake. For example, adding chia seeds and berries to oatmeal, a layer of leafy greens and tomato to a sandwich, or avocado and mushrooms to tacos.”
How Much Fiber Is Too Much?
Too much fiber is relative to how much you're currently eating. Our ancestors used to get up to 95 grams of fiber a day, but with industrialization came processed, and now ultra processed, foods, which are stripped of fiber and other essential nutrients. Therefore, fiber intake has tanked.
If you're currently consuming 10 grams of fiber a day and boost your intake to 40 grams overnight, you may experience gas, bloating, and cramping. While 30-40 grams a day may be the goal, I always recommend going slow. Aim for an additional 5-10 grams of fiber one week, along with drinking plenty of water to help move the fiber through your digestive system, and, as you tolerate the fiber boost, consider increasing the amount a bit more until you reach that goal. Go slow to avoid abdominal discomfort.
That said, there are individuals who consume an all plant-based diet and it's not uncommon for them to get 75 grams of fiber a day or more. That's okay if their body is used to it.
How to Get Fiber in Your Daily Diet
There are a number of ways that you can incorporate fiber into your daily diet. For starters, make sure that you’re getting a minimum of two servings of fruits and three servings of veggies each day. Strive to change things up and consume as many different varieties as possible. This is a great way to increase your fiber intake, but also an exceptional way to boost your nutrient intake.
Beans, lentils and peas are often missing from people’s diets, but they’re an excellent source of fiber. You don’t have to eat them every single day, but you can shoot for three times each week. They’re a great protein source if you’re eating a plant-based diet.
Nuts and seeds make a filling, healthy and high fiber snack. Eat them plain, make a trail mix using your favorite items or sprinkle them on top of a bowl of oatmeal in the morning. These foods help keep you full longer, so they’re a great way to start the day.
Replace the refined grains that you’re eating with more whole and complex varieties. White rice should be replaced with brown rice or wild rice. There are also whole grain pastas that are just as tasty as the simplified ones. You can even find grain substitutes made from things like chickpeas and lentils that up your fiber intake.
Fiber-Rich Foods List
To make things simple for you, here is a list of some of the most fiber-rich foods available.
- Pears
- Strawberries
- Avocado
- Oats
- Apples
- Raspberries
- Bananas
- Blueberries
- Carrots
- Beets
- Broccoli
- Artichokes
- Brussels Sprouts
Here's a quick look at how much dietary fiber is found in common fruits and vegetables (some mentioned above), plus I added to the list to give you more options. Always make sure you check the Nutrition Facts label for fiber content when buying packaged foods because it can change from brand to brand.
| Fruits | Serving Size | Total fiber (grams) |
|---|---|---|
| Raspberries | 1 cup | 8.0 |
| Pear | 1 | 5.5 |
| Apple | 1 | 4.5 |
| Banana | 1 | 3.0 |
| Orange | 1 | 3.0 |
| Strawberries | 1 cup | 3.0 |
| Vegetables | Serving Size | Total fiber (grams) |
|---|---|---|
| Green peas – boiled | 1 cup | 9.0 |
| Broccoli – boiled | 1 cup | 5.0 |
| Turnip Greens – boiled | 1 cup | 4.0 |
| Brussel Sprouts – boiled | 1 cup | 4.0 |
| Potato – baked | 1 | 3.5 |
| Sweet corn – boiled | 1 cup | 2.0 |
High Quality Fiber Supplements
If you’re concerned that you just don’t eat enough different foods in a day to increase your fiber intake, there are some excellent supplements to consider. Some of them can be used intermittently when you know there are gaps that exist in your nutrition that need to be addressed. Others are recommended for a more consistent basis. Here are some things to consider when shopping for a supplement.
The Type of Fiber Used
There are different types of fiber that are used for supplements, just as there are different types in food. Your best bet is to choose a product that has more than one type of fiber, resulting in a very balanced formulation.
Not all fiber supplements are created equal. There are specific fiber supplements that could help with weight loss or you could be looking for diarrhea-specific fiber supplements just to name a couple.
Quality
Unfortunately, the Food and Drug Administration doesn’t really regulate the production of supplements, so it’s hard to know when you’re getting something that is high in quality. Look for a brand that is well known, has a good deal of reviews on their website and is very transparent about their products and what ingredients are included (in addition to how those ingredients are sourced).
Supplement Form
Supplements now come in many different forms, whereas they used to always be in either a tablet or capsule. You can find fiber supplements in the form of a powder that you add to a liquid, gummies, tablets and more. Consider what you want in regard to convenience and taste.
Conclusion: Are You Getting Enough Fiber on a Daily Basis?
Now that you know a little bit more about fiber consumption and what kinds of fiber there are, you can take an in-depth look into what your diet looks like. Do you feel like you’re eating enough high-fiber foods as part of your meals? Also, consider your bowel movements. Are they regular? Are they comfortable? Do you frequently experience bouts of constipation or diarrhea? These are signs that you might need a change in your fiber intake.
A Dietitian's Tips Regarding Consuming Dietary Fiber
Fiber isn’t the easiest thing for people to consume. It’s not found in most of those tasty foods that we like to treat ourselves to. It’s not part of meat products, and you won’t find a lot of it in bread either. That’s why the people who are getting enough fiber generally follow a more plant-based lifestyle. Here are some tips I can share with you that will help you get more fiber into your diet with ease.
- Pay attention to breakfast. This is the perfect time of day to consume some additional fiber. Breakfast foods like oatmeal and fortified bran cereals are nutritious and also packed with fiber. You can top them with fruit for some extra punch.
- It’s easy to swap out the foods you normally eat with something more fiber-rich. If you’re making spaghetti, opt for a whole-grain or lentil-based version. Brown rice tastes very similar to white rice but has much more fiber.
