The fastest way to get things moving is a combination of the right foods, enough fiber, proper positioning on the toilet, and timing your bathroom visits to work with your body’s natural reflexes. Most people who struggle with constipation are eating far less fiber than they need, sitting in a position that works against their anatomy, or both. Here’s what actually works, backed by clinical evidence.
Eat More Fiber, but the Right Kind
Fiber is the single most reliable dietary fix for constipation, and most people aren’t getting nearly enough. Over 90% of women and 97% of men fall short of the recommended intake, which works out to about 25 grams a day for women and 38 grams for men on a standard diet. The general guideline is 14 grams per 1,000 calories you eat.
Not all fiber works the same way, though, and this matters more than most people realize. There are two types worth knowing about:
- Coarse insoluble fiber (like wheat bran flakes or whole vegetables) irritates the lining of your colon in a way that triggers it to secrete water and mucus, making stool easier to pass. The key word here is “coarse.” Finely ground versions of the same fiber, like some processed bran supplements, can actually make constipation worse by adding dry bulk without the moisture.
- Soluble gel-forming fiber (like psyllium husk) absorbs water and forms a gel that resists dehydration as stool moves through your colon. This keeps things soft. Because your gut bacteria can’t easily break down psyllium, it holds onto that water all the way through, which is why it’s one of the most effective fiber supplements available.
If you’re adding fiber to your diet, increase it gradually over a week or two. A sudden jump can cause bloating and gas, which defeats the purpose.
Three Foods With Strong Clinical Evidence
A clinical trial published in the American Journal of Gastroenterology compared three natural remedies head-to-head in people with chronic constipation: two green kiwifruit per day, 100 grams of prunes per day (about 10 prunes), and 12 grams of psyllium per day. All three significantly increased bowel movement frequency within four weeks.
Kiwifruit stood out in a few ways. It produced the biggest improvement in bloating, had the fewest side effects of the three, and left patients the most satisfied with their treatment. Prunes and kiwifruit both significantly improved stool consistency, making stools softer and easier to pass. Psyllium worked well too but caused more side effects like gas and bloating.
If you want to start somewhere simple, two kiwis a day or a handful of prunes is a low-risk first step that has real data behind it.
Water Alone Won’t Fix It
One of the most common pieces of advice for constipation is to drink more water. The reality is more nuanced. A controlled study in healthy volunteers found that increasing fluid intake beyond normal levels did not produce any significant change in stool output. The extra water just ended up as extra urine.
That said, if you’re genuinely dehydrated, your colon will pull more water from your stool to compensate, leaving it hard and difficult to pass. The takeaway: drink enough to stay hydrated (your urine should be pale yellow), but chugging extra glasses of water on top of that won’t get things moving. Your effort is better spent on fiber and food choices.
Use Your Body’s Built-In Timing
Your colon has a reflex called the gastrocolic reflex that ramps up movement every time you eat, especially after your first meal of the day. When food stretches your stomach, your nervous system sends a signal to your colon to start pushing things along to make room. This reflex is strongest in the morning and right after meals.
This is why sitting on the toilet 15 to 30 minutes after breakfast is one of the most effective habit changes you can make. You’re not forcing anything. You’re just giving your body the opportunity to do what it’s already trying to do. Doing this consistently, at the same time each day, trains your body to expect it, and over time your bowel movements become more regular and predictable.
Fix Your Position on the Toilet
Standard toilets are designed for comfortable sitting, not for efficient elimination. When you sit at a normal 90-degree angle, a muscle called the puborectalis wraps around your rectum and creates a kink, holding the anorectal canal at roughly 80 to 90 degrees. This is useful for continence throughout the day, but it works against you when you’re trying to go.
When you squat, that angle opens up to about 100 to 110 degrees, straightening the pathway and requiring significantly less straining. You don’t need to perch on top of your toilet to get this benefit. A simple footstool (about 7 to 9 inches tall) placed in front of your toilet lets you lean forward and bring your knees above your hips, mimicking a squat position. Research comparing sitting, hip-flexed sitting, and squatting found that the squatting position resulted in a straighter rectal canal and less strain during defecation.
Over-the-Counter Laxatives
If dietary changes aren’t enough, several types of laxatives are available without a prescription. They work through different mechanisms, and choosing the right one depends on your situation.
- Bulk-forming laxatives (psyllium, methylcellulose) work like dietary fiber, holding water in the stool to make it softer and heavier. These are the gentlest option and the closest to a long-term daily solution.
- Osmotic laxatives (polyethylene glycol, milk of magnesia, lactulose) draw water into your intestines from surrounding tissue, softening stool and increasing its volume. These are effective for occasional use when fiber alone isn’t cutting it.
- Stimulant laxatives (bisacodyl, senna) directly trigger the muscles in your intestinal wall to contract, pushing stool through faster. These work well for short-term relief but aren’t ideal for daily use because your body can become dependent on them.
- Stool softeners (docusate) lower the surface tension of stool so water and fats can penetrate it. These are the mildest option but also the least effective for true constipation. They’re most useful when you need to avoid straining, such as after surgery.
Magnesium as a Natural Osmotic
Magnesium supplements, particularly magnesium oxide and magnesium citrate, work as gentle osmotic laxatives. When magnesium reaches your intestines, it increases the osmotic pressure of the fluid inside, which pulls water into the bowel. The extra water softens and swells the stool, and the increased volume stimulates your intestinal walls to push things forward.
Magnesium oxide is commonly used at doses starting around 250 mg to 500 mg per day, taken before bed or split into divided doses. Some people respond well to as little as 250 mg, while others need more. Starting low makes sense because higher doses can cause loose stools or diarrhea. People with kidney problems should be cautious with magnesium supplements, since the kidneys are responsible for clearing excess magnesium from the blood.
Probiotics Aren’t a Reliable Fix
Probiotics are widely marketed for digestive health, but the evidence for constipation specifically is weak. A systematic review and meta-analysis found no significant difference between probiotics and placebo for increasing the number of spontaneous bowel movements per week. The strains tested included several of the most popular ones: Lactobacillus GG, Lactobacillus casei rhamnosus, and Bifidobacterium lactis. Probiotics did reduce abdominal pain and the need for enemas, which suggests some benefit for gut comfort, but they don’t reliably make you go more often.
When Constipation Signals Something Bigger
Occasional constipation is normal and usually responds to the strategies above. But certain patterns deserve a closer look. Blood in your stool, unintentional weight loss, persistent fatigue alongside constipation, sudden changes in your bowel habits, or ongoing abdominal pain are all signs worth discussing with a doctor. The same applies if you’re regularly constipated despite trying dietary and lifestyle changes, or if a medication you’re taking (particularly opioid painkillers) is the likely cause.