What are laxatives, and how do they work?
Laxatives can have powerful effects on your digestive health, helping relieve constipation and promoting regular bowel movements. They’re often used to treat constipation, a condition characterized by infrequent, difficult, and sometimes painful bowel movements.
Many natural laxatives available can be as effective as over-the-counter products at preventing constipation.
Types of laxatives
Several types of laxatives work in different ways. The main classes of laxatives include:
- Bulk-forming laxatives. These move through the body undigested, absorbing water and swelling to form stools. Commercial options of bulk-forming laxatives include Metamucil and Citrucel, which are available in powder and capsule form.
- Stool softener. These increase the amount of water absorbed by stools to make them softer and easier to pass. Stool softeners include docusate sodium and docusate calcium. They’re available in pill or tablet form.
- Lubricant laxatives. These coat the surfaces of stools and intestinal lining to keep in moisture, allowing for softer stools and easier passage. Mineral oil is an example of a lubricant laxative that’s available in liquid or enema form.
- Osmotic-type laxatives. These help the colon retain more water, increasing the frequency of bowel movements. Examples of osmotic laxatives include milk of magnesia and glycerin. These are available as a liquid, caplet, enema, or suppository.
- Saline laxatives. These draw water into the small intestine to encourage a bowel movement. Magnesium citrate is one type of saline laxative. It’s available in pill form.
- Stimulant laxatives. They speed the movement of the digestive system to induce a bowel movement. Stimulant laxatives are available as tablets, pills, powders, chewables, liquids, and suppositories under brand names like Ex-Lax, Senokot, and Dulcolax.
Over-the-counter laxatives begin to work within a few hours or may take a few days to take full effect.
Though over-the-counter laxatives can be very helpful in alleviating constipation, using them too often can cause electrolyte disturbances and changes in body salts and minerals.
If you’re looking to achieve regularity, try incorporating some natural laxatives into your routine. They can be safe and inexpensive alternatives to over-the-counter products and have minimal side effects.
List of 19 natural laxatives
1. Chia seeds
Fiber is a natural treatment and one of the first lines of defense against constipation.
It moves through the intestines undigested, adding bulk to stools and encouraging regularity.
Studies show that increasing your fiber intake can increase stool frequency and soften stools to ease their passage.
Chia seeds are particularly high in fiber, containing 9.8 grams in just 1 ounce (28.4 grams).
They mainly contain insoluble fiber, but about 7–15% of the total fiber content comprises soluble fiber.
Soluble fiber absorbs water to form a gel, which can aid the formation of softer stools to ease constipation.
Most varieties of berries are relatively high in fiber, making them a great choice as a mild natural laxative.
Strawberries contain 1.8 grams of fiber per 3/4 cup (100 grams), blueberries provide 3.6 grams of fiber per cup (150 grams), and blackberries boast just under 8 grams of fiber per cup (150 grams).
The United States Department of Agriculture (USDA) recommends eating 14 grams of dietary fiber for every 1,000 calories.
Per these recommendations, a person following a 2,000-calorie diet would eat 28 grams of fiber every day.
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Berries contain two types of fiber: soluble and insoluble.
Soluble fiber, such as that in chia seeds, absorbs water in the gut to form a gel-like substance that helps soften stools.
Insoluble fiber does not absorb water but moves through the body intact, increasing the bulk of stool for easier passage.
Including a few varieties of berries in your diet is one way to increase your fiber intake and take advantage of their natural laxative properties.
Legumes are a family of edible plants that include beans, chickpeas, lentils, peas, and peanuts.
Legumes are high in fiber, which can encourage regularity.
For example, 1 cup (180 grams) of boiled lentils contains 14.2 grams of fiber, while 1 cup (180 grams) of chickpeas provides 13.7 grams of fiber.
Eating legumes can help increase your body’s production of butyric acid, a type of short-chain fatty acid that may act as a natural laxative.
Studies show that butyric acid could help treat constipation by increasing the movement of the digestive tract.
It also acts as an anti-inflammatory agent to reduce the intestinal inflammation that may be associated with some digestive disorders, such as inflammatory bowel disease.
Boasting omega-3 fatty acids and a high amount of protein, flaxseeds are rich in many nutrients that make them a healthy addition to most diets.
Plus, flaxseeds have natural laxative properties and are an effective treatment for both constipation and diarrhea.
One study including 90 participants showed that flaxseed flour was slightly more effective than lactulose at relieving constipation.
Flaxseeds contain a good mix of both soluble and insoluble fiber, which helps reduce intestinal transit time and adds bulk to stools.
A 3/4-cup (100-gram) serving of flaxseeds provides 27.3 grams of dietary fiber.
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That said, a typical serving of flaxseed is 1 tablespoon.
Kefir is a fermented milk product.
It contains probiotics, a type of beneficial gut bacteria that have a variety of health benefits, including improved immune function and digestive health.
Consuming probiotics through either foods or supplements can increase regularity while improving stool consistency and speeding intestinal transit.
A 2014 study looked at the effects of kefir on 20 people with constipation.
After consuming 17 ounces (500 mL) per day for 4 weeks, they had increased stool frequency, improved consistency, and decreased laxative use.
6. Castor oil
Produced from castor beans, castor oil has a long history of use as a natural laxative.
After castor oil is consumed, it releases ricinoleic acid, a type of unsaturated fatty acid that’s responsible for its laxative effect.
Ricinoleic acid works by activating a specific receptor in the digestive tract that increases the movement of the intestinal muscles to induce a bowel movement.
7. Leafy greens
Leafy greens like spinach, kale, and cabbage work in a few different ways to improve regularity and prevent constipation.
First, they’re very nutrient-dense, meaning they provide a good amount of vitamins, minerals, and fiber in relatively few calories.
For example, each cup (25 grams) of raw kale provides 1 gram of fiber to help increase regularity and only has about 9 calories.
Leafy greens are also rich in magnesium. This is the main ingredient in many types of laxatives, as it helps draw water into the intestines to help pass stools.
Extracted from the plant Senna alexandrina, senna is an herb that’s often used as a natural stimulant laxative.
Senna is found in many common over-the-counter products, including Ex-Lax, Senna-Lax, and Senokot.
The constipation-relieving effects of senna are attributed to the plant’s sennoside content.
Sennosides are compounds that work by accelerating the movement of the digestive system to stimulate a bowel movement. They also increase fluid absorption in the colon to aid in the passage of stool.
Apples are high in fiber, providing 3 grams of fiber per cup (125 grams).
Plus, they’re full of pectin, a type of soluble fiber that can act as a laxative.
One 2014 study showed that pectin sped transit time in the colon. It also acted as a prebiotic by increasing the number of beneficial bacteria in the gut to promote digestive health.
10. Olive oil
Some research has found that consuming olive oil could be an effective way to alleviate constipation.
In studies, olive oil has been shown to promote bowel movements and improve the symptoms of constipation.
Rhubarb contains a compound known as sennoside A, which provides some potent laxative properties.
Sennoside A decreases the levels of AQP3, a type of protein that regulates the water content of stools.
This leads to a laxative effect by increasing the absorption of water to soften the stool and ease bowel movements.
Rhubarb also contains a good amount of fiber to help promote regularity, with 2.2 grams of fiber in each cup (122 grams).
12. Oat bran
Produced from the outer layers of the oat grain, oat bran is high in both soluble and insoluble fiber, making it a good choice as a natural laxative.
Just 1 cup (94 grams) of raw oat bran packs a whopping 14.5 grams of fiber.
Prunes are probably one of the most well-known natural laxatives.
They provide lots of fiber, with 7.7 grams in a 1-cup (248-gram) serving. They also contain a type of sugar alcohol known as sorbitol.
Sorbitol acts as a laxative when consumed in large amounts.
Several studies have found that prunes can increase stool frequency and improve consistency better than other natural laxatives, including psyllium fiber.
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Kiwifruit has been shown to have laxative properties, making it a convenient way to ease constipation.
This is mostly due to its high fiber content. One cup (180 grams) of kiwifruit contains 5.4 grams of fiber.
Kiwifruit contains a mix of both insoluble and soluble fiber. It also contains pectin, which has been shown to have a natural laxative effect.
It works by increasing the movement of the digestive tract to stimulate a bowel movement.
15. Magnesium citrate
Magnesium citrate is a powerful natural laxative.
Magnesium citrate is more bioavailable and better absorbed in the body than other forms of magnesium, such as magnesium oxide.
Magnesium citrate increases the amount of water in the intestinal tract, which causes a bowel movement.
When combined with other types of laxatives, magnesium citrate is as effective as traditional colon-cleansing regimens used before medical procedures.
For some people, coffee may increase the urge to use the bathroom. Coffee contains caffeine, which may affect the amount of time it takes for substances to move through your digestive tract, although the evidence is inconclusive.
Brewed coffee does not contain any dietary fiber, but it does have other components that may help relieve constipation. One cup (248 grams) of brewed coffee contains 247 grams of water and just under 10 mg of magnesium.
Derived from the husk and seeds of the plant Plantago ovata, psyllium is a type of fiber with laxative properties.
Psyllium husks are indigestible but retain large amounts of water, so they act as a stool bulking agent.
Although psyllium is generally safe, it can cause an intestinal obstruction if not taken with large amounts of fluids.
Water is essential for staying hydrated, maintaining regularity, preventing constipation.
Research shows that staying hydrated can help alleviate constipation by improving the consistency of stool, making it easier to pass.
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It can also amplify the effects of other natural laxatives, like fiber.
For overall health, it’s essential to get an adequate amount of water every day.
19. Sugar substitutes
Excess consumption of some types of sugar substitutes may have a laxative effect.
This is because they pass through the gut mostly unabsorbed, drawing water into the intestines and speeding transit in the gut.
This process is especially true for sugar alcohols, which are poorly absorbed in the digestive tract.
Lactitol, a type of sugar alcohol derived from milk sugar, has been investigated for its potential use in the treatment of chronic constipation.
Some case studies have even linked the excessive consumption of sugar-free chewing gum containing sorbitol, another type of sugar alcohol, to diarrhea.
Xylitol is another common sugar alcohol that acts as a laxative.
It’s usually found in small amounts in diet drinks and sugar-free gums. If you consume it in large amounts, however, it can induce a bowel movement or cause diarrhea.
Large amounts of the sugar alcohol erythritol could also exert a laxative effect in the same way, spurring a bowel movement by bringing large amounts of water into the intestines.
Risks and cautions of natural laxatives
Some natural laxatives can have negative side effects or carry risks. Before taking a natural laxative, speak with your doctor about these.
For example, the long-term, high-dose use of senna is associated with liver toxicity, and psyllium, when not taken with ample amounts of water, can cause gastrointestinal obstruction.
What’s more, drinking large amounts of coffee can lead to caffeine toxicity, which causes tremors, irregular heart rhythm, and rapid heart rate.
Some laxatives should be used with caution if you have impaired kidney function.
Laxatives come with the risk of certain side effects, such as:
- loss of normal bowel function
Some natural laxatives, such as dietary fiber, are part of a healthy diet. But if you find that you cannot have a normal bowel movement without using a laxative, speak with your doctor. The long-term use of an over-the-counter laxative can change the way your bowel functions.
Many natural laxatives can help keep you regular by increasing stool frequency and improving stool consistency.
In addition to using these natural laxatives, make sure you stay well hydrated, follow a healthy diet, and make time for regular physical activity.
These steps will help prevent constipation and keep your digestive system healthy.