How can we get enough fiber on a low carb or ketogenic diet?
If you listen to the popular narrative, then grains are an essential food group for their provision of fiber.
However, grains are far from the only food which offers fibrous carbohydrate.
In fact, a wide range of low carb foods covering fruit, nuts, seeds, and vegetables are high in fiber.
This article lists some of the best options.
Best Low Carb, High Fiber Foods
The list below contains a range of low carb foods that are high in fiber, and all of them are healthy and nutrient-dense whole foods.
Note: all nutrition data is per 100 grams raw.
- Carbs: 21.7 g
- Fiber: 12.2 g
- Calories: 575
- Fiber Density: 8.5%
Almonds are a tasty nut, and they are also impressively nutrient-dense.
In addition to their fiber content, almonds provide a wide range of nutrients, including a substantial amount of vitamin E and manganese (1).
However, almonds are very high in calories, and only a small serving size is necessary.
The great thing about almonds is that they are affordable, healthy, taste good, and offer convenience due to their portability.
- Carbs: 10.5 g
- Fiber: 5.4 g
- Calories: 47
- Fiber Density: 46%
Artichokes are a delicious and healthy vegetable that is popular around the world.
This green vegetable is very low calorie, low carb and high in fiber.
Notably, almost half of its total energy provision comes from fibrous carbohydrate.
As well as this, artichokes also provide a decent source of vitamins C, K, and the B vitamin range – especially folate (2).
They also taste delicious with a little bit of butter.
3. Avocado (California)
- Carbs: 8.6 g
- Fiber: 6.8 g
- Calories: 167
- Fiber Density: 16.3 %
One of the avocado’s best merits is its taste; they taste delicious and combine well with almost everything.
Around the world, people use them in all sorts of ways – whether alongside a bacon and egg breakfast, with steak, raw fish, or even in a spicy Mexican dish.
The avocado is also the key ingredient behind guacamole, which is one of the tastiest condiments in the world.
- Carbs: 10.2 g
- Fiber: 5.3 g
- Calories: 43
- Fiber Density: 49.3%
Blackberries are my favorite fruit, but there is no bias here – they are also one of the most fiber-rich options.
They are delicious too.
Blackberries are also full of vitamins and minerals and provide a decent source of vitamins C, K, and manganese (4).
With only 5 grams of sugar per 100 grams, they are one of the most suitable fruit options for a low carb diet.
- Carbs: 6.6 g
- Fiber: 2.6 g
- Calories: 34
- Fiber Density: 30.6%
Broccoli is one of those vegetables that people either seem to love or hate.
That said, broccoli is one of the most nutritious low-carb vegetables, and it provides a significant source of fiber for minimal calories.
Broccoli is also an excellent source of vitamins C and K1, with 100 grams providing more than 100% of the RDA for each (7).
Combining broccoli with grated cheese is a tasty way to enhance the absorption of its fat-soluble vitamins and get some protein at the same time.
6. Butternut Squash
- Carbs: 11.7 g
- Fiber: 2 g
- Calories: 45
- Fiber Density: 17.8 %
Butternut squash shares a lot in common with pumpkin, and it has a delicious, slightly sweet and nutty flavor.
Similar to pumpkin and other orange-colored plant foods, it is a significant source of carotenoids too.
Per 100 grams, butternut squash has over 200% of the RDA for vitamin A (8).
Try eating butternut squash with some butter (or another source of fat) to absorb more of this fat-soluble vitamin.
7. Coconut (Dried)
- Carbs: 23.7 g
- Fiber: 16.3 g
- Calories: 660
- Fiber Density: 9.9%
Coconut is a nut (that many people think is a fruit) that grows in tropical regions around the world.
On the positive side, coconut is one of the most versatile foods around; you can use coconut to make “milk,” coconut chips, coconut oil, coconut butter and all sorts of different products.
Notably, dried coconut flesh is a substantial source of fiber; while it contains over 23 grams of carbs per 100 grams, most of these are fibrous carbohydrate (9).
Using coconut flour is also an excellent way to get more fiber into the diet.
Coconut is also a great source of minerals such as manganese, copper, magnesium, and selenium.
8. Chia Seeds
- Carbs: 43.8 g
- Fiber: 37.7 g
- Calories: 490
- Fiber Density: 30.8 %
Seeds may not be the tastiest food in the world, but they are full of fiber, and chia seeds are reasonably nutrient-dense too.
For instance, chia seeds also provide a good amount of protein, a significant amount of omega-3 precursor ALA, and large amounts of manganese, phosphorus, and calcium (10).
Although chia seeds may not seem “low carb” since they contain more than 40 grams of carbohydrate per 100 grams, their “net” (digestible) carb content is only around 6 grams.
On the negative side, eating chia seeds alone is not the tastiest snack in the world, but they do taste a lot better in a drink or yogurt.
9. Collard Greens
- Carb: 5.7 g
- Fiber: 3.6 g
- Calories: 30
- Fiber Density: 48%
Collard greens belong to the Brassica oleracea family of plants, which is the same species that broccoli, cabbage, and kale belong to.
Although collard greens may be lesser known than these relatives, they are an excellent source of fiber – and overall nutrition.
In particular, collard greens provide huge amounts of vitamins A (133% RDA) and K (638% RDA) per 100 grams (11).
Just be sure to get enough fat alongside collard greens, since vitamins A and K1 are both fat-soluble choices.
10. Flax Seeds
- Carbs: 28.9 g
- Fiber: 27.3 g
- Calories: 534
- Fiber Density: 20.4%
Similar to chia seeds, flaxseeds are incredibly fiber-rich.
For example, out of the 28.9 grams of carbohydrate they provide, 27.3 grams of this comes from fiber (12).
Additionally, flaxseeds contain a large concentration of ALA, some of which may convert to bioavailable omega-3 in the body.
Flaxseeds are one of the most nutrient-dense foods around, and they provide large concentrations of most vitamins and minerals.
- Carbs: 9.3 g
- Fiber: 2.8 g
- Calories: 29
- Fiber Density: 38.6%
If you can handle the sour taste, lemon is an excellent low-carb source of fiber.
Not many people enjoy eating lemon on its own, but it works well in drinks – especially sparkling water.
Just like most citrus fruits, lemon provides large amounts of vitamin C, and it is reasonably low in fruit sugars (fructose) (13).
If you prefer lemon’s close relative lime, this is another low-carb and low-calorie fruit that offers similar benefits.
- Carbs: 7.0 g
- Fiber: 3.2 g
- Calories: 31
- Fiber Density: 41.3%
Although commonly believed to be a vegetable, okra is a fruit.
This rich and fibrous food now grows throughout the world but is thought to originate from Western Africa (14).
Nutritionally speaking, okra is impressive.
The fruit contains minimal calories and carbohydrate, and yet provides substantial concentrations of vitamins and minerals (15).
Additionally, with lots of fiber for only minimal calories, it’s one of the best fibrous food options for a low carb diet.
13. Pumpkin Seeds
- Carbs: 11 g
- Fiber: 6 g
- Calories: 559
- Fiber Density: 4.3%
Pumpkin seeds are a good source of fiber, protein, and several nutrients like iron, magnesium, and potassium (16).
Alongside their low carb content, pumpkin seeds contain a significant amount of fat – around 50 grams.
With their low-carb, high-fat nature, pumpkin seeds can work well for a low carb diet.
Pumpkin seeds are not one of the tastiest foods out there, but a search can quickly find some decent recipes.
- Carbs: 11.9 g
- Fiber: 6.5 g
- Calories: 52
- Fiber Density: 50%
Raspberries are another of the best-tasting low-carb fruit options.
With a soft and sweet texture and flavor, raspberries are rich in nutrients and taste.
Raspberries are very dense in fiber too, which accounts for half of their carbohydrate content (17).
Although they are great alone, raspberries taste extra delicious with a bit of heavy cream on top.
15. Sesame Seeds
- Carbs: 25.7 g
- Fiber: 14.0 g
- Calories: 565
- Fiber Density: 9.9%
Most seeds are a little lacking in the flavor department. However, this does not apply to sesame seeds.
Sesame seeds are very flavorful, and they offer a deliciously sweet and nutty taste which works well in a range of dishes.
Additionally, they are very nutrient-dense and offer substantial concentrations of most minerals.
Among these minerals, sesame seeds are especially high in calcium, copper, iron, magnesium, and manganese (18).
Lastly, they are low in net carbs and provide a decent amount of fiber.
Are Whole Grains Really Essential For Fiber?
As shown in this list of low carb foods, it is relatively easy to get enough fiber on a low carb diet.
With this in mind, how do fruit, nuts, seeds, and vegetables compare with whole grains as a source of fiber?
Fiber in Fruit, Nuts, Seeds and Vegetables vs Whole Grains (per 100 g)
The following tables compare the amount of fiber, total calories, and fiber density of common whole grains versus the foods we have looked at above.
Firstly, here are the foods we examined in this article in an easy-to-view format.
|Almonds||12.2 g||575 kcal||8.5 %|
|Artichoke||5.4 g||47 kcal||46 %|
|Avocado||6.8 g||167 kcal||16.3 %|
|Blackberries||5.3 g||43 kcal||49.3 %|
|Broccoli||2.6 g||34 kcal||30.6 %|
|Butternut Squash||2 g||45 kcal||17.8 %|
|Coconut||16.3 g||660 kcal||9.9 %|
|Chia Seeds||37.7 g||490 kcal||30.8 %|
|Collard Greens||30 g||30 kcal||48 %|
|Flax Seeds||27.3 g||534 kcal||20.4 %|
|Lemon||2.8 g||29 kcal||38.6 %|
|Okra||3.2 g||31 kcal||41.3 %|
|Pumpkin Seeds||6 g||559 kcal||4.3 %|
|Raspberries||6.5 g||52 kcal||50 %|
|Sesame Seeds||14 g||565 kcal||9.9 %|
As we can see, the fiber density of fruit, nuts, seeds, and vegetables ranges from 4.3% to 50% and averages around 30%.
|Brown Rice||3.5 g||370 kcal||3.8 %|
|Buckwheat||10 g||343 kcal||11.7 %|
|Quinoa||7 g||368 kcal||7.6 %|
|Rye Bread||5.8 g||258 kcal||9.0 %|
|Steel Cut Oats||11.4 g||386 kcal||11.8 %|
|Wholewheat Bread||6.8 g||247 kcal||11.0 %|
|Wild Rice||6.2 g||357 kcal||6.9 %|
The first thing to note here is that the total amounts of fiber per 100 grams are similar between fruit, vegetables, and grains.
However, consuming an equivalent amount of fiber to fruit and vegetables from grains requires a much higher energy intake (calories).
Generally speaking, fruit and vegetables offer the highest fiber density.
More High-Fiber Options
In addition to the foods discussed in this article, there are several more options worth mentioning.
Not all of these are what we would class as low-carb, but in their typical (small) serving size, they are still low in carbohydrate.
Here are ten more low carb, high fiber ideas;
- Cocoa Powder
- Curry Powder
- Dark Chocolate
For those who wonder “how to get fiber” on low carb diets, as this list shows, many fruits, nuts, vegetables, and seeds are fiber-rich.
Despite common belief, they also offer a more substantial serving of fiber than whole grains.
For more low carb foods high in fiber, see this guide to psyllium husk.