Best Fiber Sources for Fibermaxxing, Ranked by Grams

Not all fiber sources are created equal. If you're fibermaxxing — deliberately pushing toward 30g+ of fiber a day — you want the most grams per bite, not a vague "eat more vegetables." Below are the 15 best fiber sources ranked by grams per typical serving, so you can build high-fiber days efficiently instead of grazing on celery all afternoon.

Values are USDA averages per the serving shown. For any food not listed here, look it up in our food database — and if you don't know your daily target yet, the fiber calculator will give you your number in 30 seconds.

The ranking: most fiber per serving

1. Split peas, 1 cup cooked — 16g. The single highest-fiber serving of normal food on this list. Soup is the move.
2. Lentils, 1 cup cooked — 15.6g. Nearly identical to split peas, far more versatile.
3. Black beans, 1 cup cooked — 15g. Also pinto beans at 15g. The backbone of cheap fibermaxxing.
4. Chickpeas, 1 cup cooked — 12.5g. Hummus counts, but you need a lot of it — whole chickpeas are more efficient.
5. Chia seeds, 1 oz (2 tbsp) — 10g. The most fiber per bite of anything here. Puddings, smoothies, oatmeal.
6. Avocado, 1 cup — 10g. A whole avocado runs 10–13g depending on size.
7. Raspberries, 1 cup — 8g. Highest-fiber common fruit, and the lowest-calorie way to get there.
8. Edamame, 1 cup shelled — 8g. Plus 17g of protein. The overachiever of the list.
9. Artichoke, 1 medium — 7g. The vegetable nobody buys and everybody should.
10. Barley, 1 cup cooked — 6g. The highest-fiber common grain.
11. Pear, 1 medium — 5.5g. Eat the skin or lose half the fiber.
12. Quinoa, 1 cup cooked — 5g. Good, but barley and oats beat it per serving.
13. Broccoli, 1 cup cooked — 5g. Roasting makes it easy to eat a full cup.
14. Oats, ½ cup dry — 4g. Modest per serving, but nobody eats just half a cup's worth of benefit — it's the daily habit that matters.
15. Apple, 1 medium with skin — 4.5g. Fine, but raspberries give you nearly double for similar effort.

Soluble vs. insoluble: does the type matter?

Yes, a bit. Soluble fiber (oats, beans, apples, chia) dissolves in water and is the type most linked to healthy cholesterol levels and steady blood sugar. Insoluble fiber (whole wheat, vegetable skins, brown rice) adds bulk and keeps things moving. You don't need to track them separately — eating across categories (a legume, a grain, a fruit, a vegetable daily) covers both automatically. Our soluble vs. insoluble guide breaks down the science.

The cheapest fiber per dollar

If budget matters, the ranking reshuffles: dried lentils, split peas, oats, and popcorn deliver the most grams per dollar by a wide margin. A $2 bag of dried lentils holds roughly 100g of fiber. Berries top the nutrition ranking but cost 5–10x more per gram — buy them frozen to close the gap.

How to use this ranking

Foods that look high-fiber but aren't

The ranking above rewards honesty, so here's the flip side — popular "healthy" foods with disappointing fiber numbers:

• White rice, 1 cup cooked — 0.6g. Brown rice gives you 3.5g for the same effort. This single swap is worth ~3g daily.
• Regular pasta, 1 cup cooked — 2.5g. Whole wheat pasta doubles it to ~5g, and legume pastas (chickpea, lentil) hit 8–11g.
• Iceberg lettuce, 1 cup — 0.7g. Swap for spinach (4g per cooked cup) or kale and triple your salad's fiber.
• Orange juice, 1 cup — 0.5g. An actual orange has 3g. Juicing strips the fiber and keeps the sugar.
• Granola bars (average) — 1–2g. Most are candy bars with oats sprinkled on top. Check labels; only bars explicitly listing 5g+ count.

The pattern: refining and juicing remove fiber, while whole versions keep it. When in doubt, the less processed version wins — which is also why our complete high-fiber foods list leans heavily toward whole foods.

Building a 40g day from the ranking

Here's the ranking in action — a full day assembled from top-15 items, no supplements:

• Breakfast: Overnight oats with 2 tbsp chia seeds (10g) and ½ cup raspberries (4g) = 14g
• Lunch: 1 cup lentil soup (15.6g) with a slice of whole wheat bread (2g) = 17.6g
• Snack: 1 pear (5.5g) = 5.5g
• Dinner: You only need 3g more — a cup of broccoli (5g) as a side gets you to 42g for the day.

Does cooking destroy fiber?

Mostly no — and sometimes cooking helps. Fiber is a carbohydrate structure, not a fragile vitamin; boiling, roasting, and steaming don't meaningfully reduce it. In fact, cooking legumes is what makes their fiber (and protein) digestible in the first place — raw kidney beans are actually toxic. Two nuances: boiling vegetables and discarding the water leaches out a small amount of soluble fiber (use the cooking liquid in soups when you can), and cooling cooked starches (potatoes, rice, pasta) forms resistant starch, a bonus fiber-like compound. That leftover rice in the fridge? Slightly more fiber-effective than fresh.

Two anchor foods (chia + lentils) did 80% of the work. That's the efficiency lesson: you don't need fifteen high-fiber foods a day. You need two or three heavy hitters plus normal eating.

Pick one item from the top 5 and one from 6–15 every day, and you're most of the way to 35g before counting anything else. Example: a cup of lentils at lunch (15.6g) + chia pudding for breakfast (10g) = 25.6g, and you haven't even had dinner. Pair this list with our complete high-fiber foods list for the full picture, then confirm your personal target with the fiber calculator.

This article is for informational purposes only and is not medical advice.