Laxatives for Weight Loss
Some people use laxatives to lose weight. While laxatives can help you with constipation, using laxatives for weight loss is dangerous and can make you sick.
What Are Laxatives?
Laxatives are medicines for constipation. Your doctor usually only recommends these if you have problems passing stool even after you make changes such as eating more fiber, exercising regularly, and drinking more water.
How Do Laxatives Work?
There are different types of laxatives, and each of them causes changes in your gut that make you poop. Some laxatives soften your stool so it’s easier to pass. Others cause the muscles in your colon to push stool along. And some laxatives contain mineral oil, which coat your colon, making it slick so waste moves through easily.
Should You Use Laxatives for Weight Loss?
Some people think that laxatives will help move their food through their body before the body absorbs any calories. So, they may take laxatives after eating a big meal or binge eating. They think this helps lose weight or will stop them from gaining weight.
This is not true. Laxatives don’t stop your body from absorbing calories or from gaining weight. The food you eat goes through lots of processes before it reaches your bowel and becomes stool.
Your body absorbs calories, fat, and most nutrients before they get to the large intestine. What’s left of your food is waste that your body doesn’t need, and that is mostly full of water and some minerals. The waste moves into your large intestine, where your body absorbs some of the water, minerals, and any other healthful substances that remain.
So, if you use laxatives and lose weight, you are just losing water. As soon as you drink something, you will gain the weight back.
What Are Laxative Side Effects?
You should only take laxatives for a short period of time and as directed. If you take them for weight loss, for long periods of time, or when you don’t need them, it can cause some or all of the problems below.
Dehydration
Laxatives make you lose water. This can cause:
- Lightheadedness
- Dizziness
- Weakness
- Confusion
- Headaches
- Dark-colored pee
- Fainting
- Blurry eyesight
Sometimes, people who abuse laxatives also don’t drink any fluids, and this can be serious. In extreme cases, dehydration can cause heart problems, kidney failure, and even death.
Electrolyte imbalance
You absorb important minerals and salts called electrolytes in your colon. These are important for your muscles and nerves in your heart and colon. Electrolyte loss can cause:
- Heart problems
- Muscle weakness
- Nausea
- Vomiting
- Diarrhea
- Headaches
- Confusion
Constipation and diarrhea
Using laxatives for longer than one week can cause loss of bowel muscle tone. Because your muscles become weak, you may have trouble passing stool on your own. Laxatives can cause long-term constipation, but they can cause diarrhea, too.
Damage to intestines
Using laxatives too often and for too long can damage your intestines. This can lead to a greater chance of having colon cancer.
Medications
Taking laxatives can stop your prescription medications from working properly. This can cause serious health problems.
Eating disorder
People who use laxatives to lose weight are more likely to get an eating disorder.
Other side effects
Laxatives can cause other serious problems in your digestive tract. You should see your doctor right away if you bleed from your rectum or don’t have any bowel movements, as these are serious health problems.
How to Lose Weight Safely
Talk to your doctor about whether you need to lose weight. Sometimes, you may feel you need to be thinner when you really don’t need to be. If you have a risk for heart problems and diabetes, you may need to lose weight. But using diet pills and laxatives is not a safe way to manage your weight.
It is possible to lose weight safely with basic lifestyle changes.
Healthy diet, hydration, and fiber intake
The first step in losing weight is to look at what you’re putting into your body, says Wiljon Beltre, MD, a bariatric and metabolic surgeon in Orlando, Florida. “What foods are you eating that are contributing to your excess weight? Are you consuming too many sodas, too many refined carbs like pasta or juices loaded with sugar?”
Beltre says eating fewer calories, choosing healthy snacks, and cutting down on sugary drinks and alcohol can help you lose weight.
Eating more fruits and vegetables can help, too. According to the USDA, adults should eat at least 2 cups of fruits and vegetables each day. And drink more water. It’ll keep you hydrated and help you feel full.
Regular exercise
Aim for at least 150 minutes of aerobic activity each week. This will help get your heart rate up and keep your heart and lungs healthy. You should also add strength training to your workout twice a week. This will raise your metabolism and help you burn more calories.
“Consistency is key. Remember, this is a long-term lifestyle change, not a quick-fix diet trend,” says Alicia Shelly, MD, a board-certified Internal Medicine and Diplomate of the American Board of Obesity Medicine at Wellstar Medical Center in Douglasville, GA.
Weight loss medication
If you’re eating right and exercising but still struggling to lose weight, it may be time to talk to your doctor. They can prescribe medications to help you lose weight. Beltre says if you struggle with hunger and cravings, your doctor can prescribe pills such as phentermine (Adipex-P, Lomaira) or injections such as semaglutide to control them.
Professional weight loss support
If you have an eating disorder, it’s important to talk to your doctor about your weight and your habits. You should also talk to your doctor if you’re thinking about starting laxatives to lose weight. This may be a sign that you should see a counselor.
Takeaways
Laxatives should only be used for constipation; they don’t help you lose weight. If you do lose weight while taking laxatives, it’s because your body is losing water and electrolytes — not fat. Laxatives don’t stop your body from absorbing calories. Your body takes all the calories and nutrients it needs from your food before it passes to your bowel as waste. If you take laxatives for more than one week, you may have serious side effects, such as dehydration, diarrhea, or bleeding from your rectum.
Laxatives for Weight Loss FAQs
How long after taking laxatives do you poop?
It depends on which type you take. Some things such as enemas and suppositories can work within minutes. Bulk-forming laxatives, such as psyllium (Metamucil), could take days to work.
What is the most effective laxative?
The most effective laxatives are osmotic laxatives, such as polyethylene glycol (Gavilax, Miralax). These pull water from other parts of your body into your colon. The extra water softens your stool and makes it easier to pass.
Do laxatives flush out calories?
No, they don’t. Your body takes all the calories and nutrients it needs from your food long before it reaches your bowel. Laxatives do absorb water and essential minerals, called electrolytes. These help keep you hydrated, balance your pH levels, and control chemical reactions in the body.
