Updated: May 9
Enjoy the relief of a good bowel movement: here’s how to make that happen. As naturopathic doctors we often turn to two common natural substances to relieve constipation: magnesium and vitamin C.
Magnesium promotes peristalsis. Peristalsis is the coordinated wave-like muscular action that moves things through the bowel. Taking magnesium helps speed this up and makes the waves stronger. Vitamin C allows the bowel to hold more water, making a dry stool softer. You may have heard of taking vitamin C “to bowel tolerance” which means the amount of vitamin C that triggers diarrhea. This amount can vary widely from one person to the next. It usually takes several grams of Vitamin C (one gram is 1,000 mg), taken all at the same time, to cause loose stools. Not all forms of magnesium are the same when it comes to promoting bowel movements: Magnesium oxide, as in milk of magnesia, is poorly absorbed into the body, so lots stays in the bowel. This form is primarily used for its laxative effect.
Magnesium citrate is more absorbable, but a significant amount remains to stimulate the bowel. This is our preferred form for helping with constipation.
Magnesium glycinate (also known as magnesium bisglycinate) is better absorbed, so it’s great to help with muscle spasms, menstrual cramps, tension headaches and so on, but not as helpful in treating constipation.
How to get going with these tools: Magnesium citrate is available in powders, liquids or capsules. Using a powder or liquid makes it easier to step up your dose gently. 200 mg at bedtime is usually a good starting place.
If that doesn’t do the trick, increase the dose by 100-200 mg a night until you have a smooth easy bowel movement the next day. For most people this usually happens when taking 400-600 mg of magnesium citrate a day. Vitamin C can be added if magnesium alone is not sufficient, or if your stool is hard and dry. We suggest starting with 2,000 mg (2g) at a time, taken together with the magnesium. You can increase by 500 mg to 1,000 mg a day, depending on how bad your constipation is, and how dry your stool is. Vitamin C is safe taken in large amounts: the known side-effect is diarrhea. If you reach that point, reduce your dose by about 20%. This reduced dose will likely be the right dose for you. With both magnesium and vitamin C, you can finesse your dose once you have got things moving daily. We don’t recommend going higher than 800 mg of magnesium and 10 grams of vitamin C. If these don’t get things going, consult a regulated health practitioner. People with an actual bowel blockage should not use this protocol: they need personal medical help. Long term laxative use may cause dependency and have other adverse effects. Unlike laxatives, both magnesium and vitamin C are safe to take on a regular basis, to keep you regular!