Causes of Hard, Small, and Pellet-Like Stool

If you have small, hard poop that's shaped like pellets, it's usually a sign of constipation, or infrequent bowel movements. Most often, constipation happens if your diet is low in fiber. Hydration and physical activity can also play a role. Constipation can also occur with certain medications or medical conditions that interfere with the functioning of your bowels.

This article details five possible reasons why your poop looks like pellets and when it's time to see a doctor.

what makes your stool look like rabbit pellets?
Illustration by Joshua Seong, Verywell

Too Little Fiber

The size of your stool is influenced by the amount of fiber you consume. Plant-based fiber from vegetables, fruits, and whole grains adds bulk to your stool. It also promotes fermentation and creates a gel that keeps poop from breaking into pieces.

If you have enough fiber in your diet, your stool should be soft, well-formed, and easy to pass. If you don't, your stool is more likely to be hard, dark, pebble-like, and difficult to pass.

On average, adults consume less than 15 grams of fiber per day—far less than the recommended 38 grams for males and 25 grams for females under the age of 50.

If you're not sure how much fiber you're eating, try keeping a food diary. If you use a diet-related smartphone app, it may already be tracking your fiber intake for you.

By keeping track of how much fiber you consume, you can see if you are getting enough and increase your intake if needed.

Here are some fiber-rich foods to add to your diet:

 Food  Grams of Fiber
 Lentils 15.6 per cup
 Avocados 7.8 per half-cup
Raspberries 8 per cup, raw
Green peas 7 per cup
Chia seeds 5.5 per tablespoon
Oatmeal 4 per cup, cooked
Almonds 3.3 per 24 nuts
Ground flaxseed  1.9 per tablespoon

Increase your intake gradually to avoid bloating and gas. Fiber supplements can also help if you still having trouble with constipation.


Small, hard, pellet-like stools are most often the result of a low-fiber diet. Increasing your fiber intake and taking a fiber supplement, if needed, may help ease bowel movements.

Not Enough Fluids

Soluble fiber is the type that dissolves in water and includes plant-based pectin and gums that hold stools together

Fiber and water work together to make stools that are easy to pass. If you aren't drinking enough water, there won't be enough in the gut for soluble fiber to absorb.

When it comes to getting enough water, many experts will tell you to use thirst as a guide and to look for varied sources such as fruits, vegetables, herbal teas, juices, soups, and non-caffeinated beverages.

According to the Institute of Medicine (IOM), you should consume no less than 15.5 cups of fluids per day from all sources if you are an adult male and 11.5 cups if you are an adult female. Factors like age, body weight, activity level, and certain health conditions may require you to increase or decrease your intake.

If you aren't sure how much water is right for you, speak with your doctor.


Your body needs water to dissolve soluble fiber in the gut. Adult males should consume no less than 15.5 cups of water per day, while adult female should consume no less than 11.5 cups per day from all sources.


Your constipation may have nothing to do with fiber or water. In some cases, the drugs or supplements you take can alter the way that your body digests food.

These include medications such as :

If you are on any of these and are constipated, let your doctor know. In some cases, the drug dose may be adjusted or the treatment changed. Stool softeners may also help ease the passing of stools.

Lifestyle Issues

Spending hours at your desk hunched over a keyboard or leading a sedentary lifestyle can slow digestion. By contrast, moving around helps stimulate the gut and speeds the passage of stools before too much water is absorbed.

If you are stuck at a desk, get up and move every hour or so to improve your digestion. It also helps to exercise regularly. Even 30 minutes of low-impact activity every day, such as a brisk walk, will help.

Make time to go to the bathroom if you feel the urge to go. Ignoring the urge can make constipation worse.

You can also try getting up earlier to eat breakfast, which can promote bowel movements before your day really gets started.


Physical activity promotes the movement of stool through the intestines. Instead of sitting at your desk all day, get up and move every hour so. Regular exercise also helps.

Health Conditions

Constipation can sometimes be a sign of an underlying health condition. Some of these can slow the movement of stools through the gut, while others reduce the level of digestive enzymes the body produces.

Conditions linked to constipation include:

In cases like these, constipation is usually treated with diet, exercise, laxatives, and/or stool softeners. The treatment of the underlying condition is also crucial.

When to See a Doctor

Having small stools from time to time is usually nothing to worry about. However, speak with a doctor if they last for longer than two weeks and you don't know why.

If hard, pebble-like stools are accompanied by symptoms such as cramping, fever, nausea, vomiting, or rectal bleeding, see a doctor immediately. These could be signs of a more serious health issue.


Constipation with small, hard, pebble-like stools is generally a sign of a low-fiber diet. Other contributing factors including drinking too little water or having an inactive lifestyle.

Certain medications and medical conditions can also cause constipation, even if you are active and consume plenty of fiber.

If constipation lasts more than two weeks and has no known cause, speak with a doctor.

A Word From Verywell

The first thing some people do when they have constipation is reach for a laxative. This can be a problem for two reasons.

Firstly, the practice can lead to laxative dependence in which you're only be able to go when you take the medication. Secondly, laxatives can mask the underlying cause of constipation, meaning it may go undetected until the condition becomes more serious.

In the end, there is no such thing as "normal" chronic constipation. If you are struggling on a regular basis, see a doctor. Even if you are otherwise healthy, there are strategies beyond laxatives that can help.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Cathy Wong
Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health.