Nutrition Diet: What vegetable is the lowest in fiber?

October 20, 2025 •

4 min read

While most vegetables are praised for their fiber content, certain health conditions or medical procedures require a low-fiber diet. A standout contender for answering the question, "What vegetable is the lowest in fiber?", is iceberg lettuce, with approximately 0.7 grams of dietary fiber per cup of shredded leaves, followed closely by peeled cucumbers. This article provides a comprehensive guide to selecting and preparing low-fiber vegetables for those with specific dietary needs.

Quick Summary

Iceberg lettuce and peeled cucumbers are among the lowest-fiber vegetables available, making them suitable for low-fiber diets. Cooking and removing skins and seeds from other vegetables, like squash, potatoes, and carrots, can also significantly reduce their fiber content.

Key Points

Iceberg Lettuce is One of the Lowest: With its high water content, iceberg lettuce offers very minimal dietary fiber, making it a top choice for a low-fiber diet.
Peeled Cucumbers are Highly Suitable: For an even lower fiber option, consume peeled and deseeded cucumbers, which contain less than half a gram of fiber per half-cup serving.
Cooking Reduces Fiber: Thoroughly cooking vegetables like carrots, spinach, and squash breaks down tough fibers and makes them easier to digest.
Remove Skins and Seeds: The skin and seeds of many vegetables contain the highest concentration of fiber. Peeling potatoes, carrots, and zucchini is a critical step.
Low-Fiber Diets Are Often Temporary: A low-fiber diet is typically recommended for specific medical conditions or procedures and should be supervised by a healthcare professional.
Canned Vegetables are an Option: Canned options like green beans or carrots are generally well-cooked and often processed without skins or seeds, providing a convenient low-fiber choice.

Understanding Dietary Fiber

Dietary fiber is a type of carbohydrate found in plant-based foods that the human body cannot digest. It is crucial for maintaining digestive health and can be found in high concentrations in foods like legumes, whole grains, nuts, and most fruits and vegetables. However, there are times when a low-fiber diet, also known as a low-residue diet, is necessary. This may be prescribed for conditions such as inflammatory bowel disease, diverticulitis flare-ups, or before certain medical procedures like a colonoscopy.

During these periods, reducing the amount of undigested material passing through the digestive tract is essential to minimize irritation and allow the bowel to rest. Fortunately, many vegetables can still be incorporated into a low-fiber plan, especially when prepared correctly.

The Top Contenders: Lowest in Fiber

When searching for vegetables with the absolute lowest fiber content, focusing on those with a high water content is key. Iceberg lettuce and peeled cucumbers consistently rank at the top of this list.

Iceberg Lettuce: Often dismissed as nutritionally inferior to darker leafy greens, iceberg lettuce is valued on a low-fiber diet due to its high water content and mild flavor. A single cup of shredded iceberg lettuce contains roughly 0.7 to 1 gram of fiber, making it a safe choice for salads in small quantities.
Peeled Cucumber: With its refreshing taste and high water volume, a half-cup of sliced, peeled cucumber contains only about 0.3 grams of fiber. Removing the skin and seeds is crucial, as that's where most of the fiber is concentrated.
Other Low-Fiber Raw Vegetables: Raw alfalfa sprouts and cress are also very low in fiber.

How Cooking Reduces Fiber

For many other vegetables, preparation methods can drastically alter their fiber content. Cooking tenderizes the plant tissue, making the fiber less abrasive to the digestive tract.

Best practices for low-fiber vegetables:

Cook thoroughly: Steaming, boiling, or baking until very tender is ideal.
Peel off the skin: The skin is often the most fibrous part of the vegetable. Examples include potatoes, zucchini, carrots, and sweet potatoes.
Remove seeds: For vegetables like cucumbers, zucchini, and squash, scooping out the seedy center significantly reduces fiber.
Consider canned: Canned vegetables are typically cooked until very tender and are processed without seeds or skins, making them a suitable option.
Strain juices and sauces: Removing pulp from fruit and vegetable juices is another way to enjoy nutrients while minimizing fiber.

A Comparison of Vegetables by Fiber Content

To better illustrate the differences, here is a comparison of the approximate fiber content per standard serving, demonstrating how preparation affects the final fiber count.


Vegetable	Preparation	Fiber Content (per 1 cup)	Notes
Iceberg Lettuce	Raw, shredded	~0.7-1g	Highest water content among lettuces.
Cucumber	Peeled, sliced	~0.3g (per ½ cup)	Remove seeds and skin.
Carrots	Raw	~3.6g	Higher fiber raw, should be cooked.
Carrots	Well-cooked, peeled	~1-2g	Softer fiber is easier to digest.
Asparagus	Cooked, tender tips	~2.8g	Avoid tough stalks.
Spinach	Cooked	~4.3g	Raw spinach has insoluble fiber, while cooking can make it more tolerable for some.
Zucchini	Peeled, cooked	~1g	Always peel and remove seeds.
Potatoes	Peeled, cooked	~2g	Remove the high-fiber skin.
Broccoli	Cooked florets	~5.1g	Even cooked, it is a medium-fiber food.

Low-Fiber Vegetables in Your Diet

Integrating low-fiber vegetables into your meals requires a bit of mindfulness. Instead of relying on a single option, aim for variety within the list of approved vegetables to ensure you're still getting a range of vitamins and minerals.

Meal ideas for a low-fiber diet:

Breakfast: A smooth vegetable juice (strained) or peeled, cooked carrots stirred into a dish.
Lunch: A small salad with shredded iceberg lettuce and peeled, deseeded cucumbers. Use a dressing without seeds.
Dinner: Baked or boiled peeled potato, served alongside well-cooked, tender carrots or green beans (canned or cooked).
Snacks: Cooked vegetable purée, smooth tomato paste (no seeds or skins), or a few peeled, cooked asparagus tips.

Who Needs a Low-Fiber Diet?

A low-fiber diet is not meant for long-term use unless medically supervised, as it can lead to nutrient deficiencies over time. Common reasons for adopting a temporary low-fiber plan include:

Inflammatory Bowel Disease (IBD): During flare-ups of Crohn's disease or ulcerative colitis, a low-fiber diet can help reduce symptoms.
Diverticulitis: A low-residue diet is often recommended during a flare-up to allow the colon to heal.
Colonoscopy Preparation: Following a low-fiber diet in the days leading up to the procedure is crucial for clearing the colon.
Radiation Therapy: For radiation targeting the pelvic or abdominal area, a low-fiber diet can help reduce irritation to the bowels.

For more detailed guidance on a low-fiber diet, consult resources like the MedlinePlus Medical Encyclopedia.

Conclusion

For those needing to follow a low-fiber diet, understanding which vegetables to choose and how to prepare them is essential. While many vegetables are high in fiber, options like iceberg lettuce and peeled cucumbers offer very low fiber content by nature. For other vegetables, cooking and removing skins or seeds can make them more suitable. By selecting a variety of these low-fiber options and preparing them correctly, individuals can meet their nutritional needs while managing specific health conditions or preparing for medical procedures.

Frequently Asked Questions

The vegetable with the lowest fiber content is generally considered to be iceberg lettuce, followed closely by peeled and deseeded cucumbers. A cup of shredded iceberg lettuce contains around 0.7 grams of fiber.

A low-fiber diet is often prescribed to reduce irritation in the digestive tract, such as during flare-ups of inflammatory bowel disease or diverticulitis. It is also a necessary preparation for certain medical procedures like a colonoscopy.

Yes, many other vegetables can be included if they are properly prepared. This typically involves thoroughly cooking them, peeling off the skin, and removing any seeds.

Yes, cooking tenderizes the plant fibers, making them less abrasive and easier for the digestive system to handle. This is why well-cooked, peeled vegetables are often allowed on a low-fiber diet.

Yes, strained vegetable juice without pulp is an excellent low-fiber option. It provides nutrients from vegetables without the tough, indigestible fibers.

You should avoid high-fiber vegetables, especially when raw, such as broccoli, cauliflower, corn, Brussels sprouts, and asparagus with tough stalks. Also avoid vegetable skins and seeds.

No, a low-fiber diet is generally not recommended for long-term use as it can lead to nutritional deficiencies. It should only be followed under the guidance of a healthcare professional.