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Magnesium helps against constipation and irritable bowel syndrome

Magnesium helps against constipation and irritable bowel syndromeIt is usually dietary fiber and water that get mentioned when the discussion is about constipation and irritable bowel syndrome. However, we also need an adequate intake of magnesium, as this minerals affects our digestion by way of several different mechanisms. Constipation is associated with numerous complaints and conditions such as headache, bad mood, eczema, and aching joints, so it is important to rid the body of toxins and empty the bowel, preferably 1-2 times daily.

Magnesium is involved in over 300 different enzymatic processes and is important for bone health, muscle function, the nervous system, blood pressure, the heart, the immune defense, and numerous other functions. Because of its many roles, things may really become unhinged if we fail to get enough of this mineral. Our digestive system is vulnerable to magnesium deficiency, as the entire intestinal system contains muscles (smooth muscle tissue), and there is an abundance of nerves in our intestines, as well.

Magnesium deficiency and dehydration

A large Japanese study looked at 3,835 students, 26.2% of whom suffered from constipation. The participants' fiber intake was relatively low, and their constipation was typically combined with a low intake of magnesium and liquids.

The laxative effect of magnesium is controlled via the following mechanisms:

  • Magnesium helps relax the muscles of the intestinal wall - including the sphincter between the small intestine and large intestine and between the large intestine and rectum. This facilitates the passage of food and feces through the digestive tract without inappropriate blockages caused by muscle tension
  • Magnesium attracts water in the large intestine, helping to soften the feces, whereby it can pass more easily through the intestine, helped by the peristaltic movements. For that reason, it is important that we get sufficient amounts of magnesium and liquid.

When stress triggers a magnesium deficiency, constipation, and irritable bowel syndrome

15-30% of Europeans suffer from irritable bowel syndrome with constipation and alternating bowel behavior. Stress is often a contributing factor, the reason being that when we experience stress we react with primeval fight-or-flight reactions that send massive amounts of blood from our digestive system to our brain and muscles to enable us to perform optimally in challenging situations. These primeval reactions affect our digestion if they prevail for longer periods of time.
Therefore, it is vital to get enough sleep and relaxation in order ensure that the digestive system is prioritized correctly in terms of getting sufficient amounts of blood and energy. A magnesium supplement may also be worth considering as a way of supporting the nervous system during and after periods with stress.

Common causes of a magnesium deficiency

  • Stress
  • Insufficient diet and long-term dieting
  • Lack of vitamin B6, causing poor absorption in the cells
  • Too much calcium, phosphorous, and sodium
  • Too much oxalic acid (found in tea, spinach, cocoa, and rhubarb)
  • A large consumption of alcohol and other stimulants
  • Diuretics

Important balance between magnesium and calcium

There is an intricate interaction between calcium and magnesium inside the cells, which calls for a balance between the two minerals. Too much calcium from dairy products and supplements is a common cause of constipation, especially when there is also too little magnesium. The ratio between magnesium and calcium should normally be 1:2. In Asian countries where the major part of the population does not consume dairy products but rather a large amount of vegetables, the magnesium-calcium ratio is closer to 1:1

Magnesium supplements - a small quality test

Some magnesium supplements contain a blend of organic and inorganic magnesium sources, as this increases the utilization of the mineral. Not all magnesium supplements are absorbed equally well in the body, however, and if they merely pass through the digestive system without being absorbed, they are unlikely to have an effect. It is easy to conduct a simple test by dropping a magnesium tablet into a glass of water to see if it dissolves within a few minutes. Fast dissolution of the tablet gives a better guarantee that the body is able to absorb the magnesium content of the supplement.

Magnesia does not improve the body's magnesium status

Magnesia (magnesium oxide) is commonly prescribed for constipation. This magnesium source is very difficult to absorb, however, and it does not increase the body's magnesium status.

Magnesium intake in earlier days, and RDA levels

Good magnesium sources include kernels, almonds, nuts, seeds, whole-grain, and vegetables. Before the industrialization, the average daily intake of magnesium was around 500 mg. Today, many of us get less than the current RDA level (Recommended Daily Allowance), which is 3-400 mg (depending on the country.)

Are you drinking enough liquids?

It is important to make sure to drink enough liquids, as there is a relation between magnesium deficiency, dehydration, and constipation.

The normal need for liquid is 30 ml for every kilo of body weight. In other words, a person who weighs 70 kilos should ideally drink around 2.1 liters of liquid every day. The need for liquid automatically increases when you sweat a lot.

Constipation may cause headache and many other symptoms

Constipation is a common cause of headache, mood swings, eczema, muscle soreness, and aching joints. When the liver breaks down toxic metabolites and other toxins, they are removed with the bile and sent to the digestive system. In the case of constipation, however, there is a risk that these toxins get absorbed in the large intestine and transferred to the bloodstream rather than being discharged. In the light of this, constipation is like a poising of the body and may result in different symptoms, depending on where the toxins accumulate and how the immune system reacts.

Good digestion gives physical and mental well-being

Many people find that their good mood returns and their headache and other symptoms disappear into thin air, once their constipation stops and they are able to empty their bowel completely 1-2 times daily, which is optimal.


Murakami K et al. Association between dietary fiber, water and magnesium intake and functional constipation among young Japanese women. Eur J Clin Nutr.

Lorn Alison. Magnesium and Constipation.

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