Many weight loss solutions have been proposed over the years, some of them effective, others not. Laxatives are one of the newest. The idea is that when food goes through the colon fast enough, the body has no time to absorb the calories it contains. The products come in many forms, from pills and syrups to a variety of teas, most commonly senna tea.
Not surprisingly, the use of laxatives for weight loss is questionable at best. Most experts agree that if it does work, it’s not the result of the laxative itself—it’s because your body is spending so much energy trying to figure out and adjust to the new system you’ve created. And that weight loss is temporary, if fast—once your body gets used to it, you may start gaining weight again.
The first risk is dehydration. Laxatives work by forcing the colon and intestines to absorb fluids, which soften stools for easier passage. When used to treat constipation, the amount of liquid absorbed is controlled through proper dosage. Patients are also usually advised to drink lots of water. But too much laxatives can deplete the body of essential fluids, and extreme dehydration can lead to electrolyte imbalance. This in turn can cause muscle weakness, drowsiness, and in severe cases even seizures and heart dysfunction.
Other laxatives lubricate the digestive tract, and others by inducing peristalsis, the muscle contractions that push stools through the large intestine and colon. No matter how they work, though, the science does not hold: calories and nutrients are absorbed long before they reach the intestines.
If you have digestive problems that lead to weight gain or water retention, then laxative-like products may be helpful. Certain teas, for example, are known to aid in digestion and can be taken after meals. But medicinal laxatives for weight loss are more harmful than productive. When taken for extended periods, it can cause a whole range of side effects, from chronic diarrhea and vomiting to rectal bleeding and gastrointestinal disease. You can also become dependent on laxatives, which means you cannot have regular bowel movements without them.
Weight loss is never an overnight affair. Anything that promises fast weight loss is either ineffective or dangerous, or both. Eating right and getting ample exercise is still the best way to go about it. If you aim for long-term health rather than quick weight loss, your ideal weight will come without you even trying.