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8 Side Effects of Taking Magnesium Supplements

Side effects of taking magnesium

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If you’re taking magnesium, let’s talk about the side effects you should know.

Magnesium is one of the most common supplements today. It’s increasingly popular as people become more aware of the many benefits of magnesium.

Most Canadian adults and children could use a magnesium supplement like Natural Calm. In fact, the government of Canada reports that over 34% of Canadians over the age of 19 consume less than the recommended daily amount of the essential mineral, with the prevalence of inadequate intakes rising. 

Magnesium supplements can help fill the gap in our diets and compensate for poor nutrient absorption.

Side Effects of Taking Magnesium

But what are the side effects of taking magnesium supplements? Are there any negative side effects to watch out for? Any positive “side effects” that you love but didn’t anticipate?

For example, sometimes magnesium is reported to cause loose bowel movements, but on the other hand, it helps many people stay regular. Whether you see this as an unwanted or desired side effect of taking magnesium is entirely personal.

Elevated magnesium levels do offer a wide range of benefits, including (but not limited to) better sleep, improved stress levels, maintenance of healthy blood pressure. You may be wondering, at what cost?

In this post we’ll look at the side effects of taking magnesium, both positive and negative, and explore the pros and cons for different people with different needs and lifestyles. 

In great news, the risks of taking magnesium are exceedingly low for most people. Make sure you take this supplement as directed and you can enjoy the benefits without downsides.

You May Notice Improved Sleep

Dubbed “the sleep mineral”, magnesium is known to improve both the quantity and quality of sleep. Even if your primary reason for taking it isn’t to address a sleep issue, you may notice better sleep as a side effect of taking magnesium.

How does it work? First, magnesium relaxes the mind by activating the parasympathetic branch of the nervous system, allowing the brain to wind down its activity so you can relax and slip into sleep. 

At the same time, magnesium interacts with hormones (cortisol, adrenaline) and neurotransmitters (GABA) to minimize anxiety and stress, which can improve sleep quality. Magnesium also seems to regulate the pineal gland’s release of melatonin, a hormone essential to making us feel sleepy at the right times. 

Magnesium doesn’t only relax the brain. This key mineral also eases the muscles and nerves so you can get a good sleep. By relaxing the body, magnesium relieves a number of conditions that are known to impede sleep, such as digestive issues and restless leg syndrome. Similarly, if chronic pain is keeping you up, magnesium has shown promise in reducing pain associated with arthritis, migraines, back pain, and fibromyalgia. 

More generally, a very prevalent symptom of magnesium deficiency is new or worsened insomnia, and since the majority of Canadians do not get enough magnesium from their diets, it’s very possible that a magnesium supplement could do wonders for your sleep. 

In short, magnesium prepares the body and mind for a good night’s sleep, and works to reduce the effects of health concerns that negatively affect sleep. This is a side effect we can live with!

Magnesium May React with Other Medications

If you take medications, it’s always important to talk to your healthcare provider about any potential negative interactions. Any reaction with medication is an unwanted side effect of taking magnesium.

Although rare, magnesium may interfere with the absorption of certain drugs, reducing their effect. Antibiotics, in particular, require special attention if you are also taking magnesium supplements. It is possible to take both, but magnesium must be taken a minimum of 1 hour before or 2 hours after antibiotics to make sure they are properly absorbed. 

If you take blood pressure medications (calcium channel blockers), note that magnesium may increase the negative effects of the medication itself, diabetic medications, digoxin, levothyroxin, and penicillamine. 

On the other hand, there are medications that deplete your magnesium, in which case it could be important that you supplement to make up for the loss. Some of these include estrogen replacement therapy, the immunosuppressant medication tacrolimus, and some kinds of diuretics.

In general, it is a good, safe practice to ask your doctor about interactions with your medication, no matter what it is that you are taking. 

Loosens Bowel Movements and Relieves Constipation

Some people take magnesium to stay regular — others only notice it as a side effect.

Magnesium has a natural laxative effect and prevents future constipation concerns both by stool softening, and by relaxing the muscles associated with elimination. 

Magnesium citrate works as an osmotic laxative. That is, it pulls water into the intestines, combining with dry stool and making it easier to pass. The addition of water also stimulates bowel motility (motion). One thing that’s important to keep in mind with this is that since the water to loosen stools is pulled from elsewhere in the body, it’s best to drink lots of water to remain hydrated while magnesium does its job. 

Magnesium will also relax the muscles of the intestines, the same way it relaxes muscles everywhere else in the body. This allows for smoother passage through the gastrointestinal tract. 

Early research has suggested that magnesium may relieve certain symptoms of constipation-predominant irritable bowel syndrome (IBS-C), but since this condition presents itself in very different ways in different people, IBS patients are encouraged to consult with their doctors about whether magnesium is the right choice for them.

The unique benefit that magnesium offers is that it is a natural solution for occasional constipation. Laxative medications have the possibility of flushing good bacteria and electrolytes out of your intestines along with waste. Instead of risking this, magnesium simply encourages the normal course of action, without any of the harsh effects of regular laxatives. 

If you notice this side effect of taking magnesium, don’t worry. Just take less or a smaller dose at any one time.

Vomiting and Nausea  

Dramatic side effects, such as nausea or vomiting, are linked to extreme dosage. In very high amounts, magnesium can cause these symptoms. This is called magnesium toxicity, or hypermagnesemia, and we’ll talk about it more a little later. 

Magnesium is an electrolyte that interacts with sodium in the body, particularly during digestion in the small intestine and colon. In large doses, magnesium could interfere with normal digestion, causing some abdominal discomfort or loose stools. However, these symptoms are only associated with excessive magnesium consumption. 

Under normal circumstances, magnesium supplements shouldn’t cause dramatic symptoms. Be sure to always consult your physician before taking a new or unfamiliar supplement, and always follow the dosing guidelines.

Most people should never experience vomiting and nausea as a side effect of taking magnesium properly. 

Improved Stress Levels

Magnesium plays a key role in regulating our stress response, which can be a very positive side effect of taking magnesium (even if it wasn’t your original reason for supplementing).

Simply put, magnesium reduces stress and anxiety by calming the nervous system. This process does involve some complex neurobiology, so we’ll give a quick background on how stress presents itself at the neurological level, and then talk about how magnesium comes into play. 

When the body is in stress, that is, when it has received some kind of signal that it is unsafe or there is something to worry about, the brain releases a number of different hormones associated with this state. The most famous of these are cortisol and adrenaline (formally known as epinephrine). 

While they may be less helpful to us in everyday stressful situations related to work or personal life, these hormones are what make it possible for the body to access the fight or flight response. 

For example, if your body believes you to be in danger, cortisol and epinephrine allow you to quickly recognize the need to take action, and then get your blood pumping and heart racing so you can run away from the threat. 

Although these processes do serve a purpose, it’s unhealthy to have consistently high levels of stress hormones. It is unsustainable and taxing on the body in the long term. Furthermore, sustained states of stress can lead to more prolonged chronic anxiety. 

Enter: magnesium. 

If present in adequate quantity, magnesium will inhibit the production of cortisol and epinephrine by the adrenal glands. This moderation of the hormones helps your brain to regulate feelings of stress in the day to day, and prevent you from falling victim to the vicious cycle that can happen with magnesium deficiency and stress. Magnesium depletion exacerbates stress symptoms, and stress, in turn, depletes magnesium in the body. 

Maintaining good magnesium levels through diet or supplements is a great way to minimize stress! If you notice your sleep has improved since taking magnesium, now you know why.

Magnesium Toxicity

Though overdosing on magnesium is very rare for typical healthy individuals, it can happen, and that’s when one would see side effects like diarrhea, abdominal pain, nausea, and vomiting. 

Magnesium toxicity is called hypermagnesemia, and results from too much magnesium in the blood.

Other symptoms include:

  • Facial flushing 
  • Muscle weakness
  • Low blood pressure
  • Lethargy and fatigue
  • Urine retention 

These symptoms can range from mild to serious. 

Hypermagnesemia poses a relatively low risk since excess magnesium is routinely eliminated by the kidneys through urine, but these unpleasant symptoms (nausea, abdominal pain – the others on the list are rare) may persist while the body works at flushing out the excess. 

Avoiding these side effects comes down to picking the right magnesium supplement and dosage for your individual needs. As the saying goes, “everything in moderation” – your body will absorb magnesium best with regular, moderate doses. Avoiding extreme amounts will help avoid extreme side effects. 

Hypermagnesemia is a dramatic situation. Most of the time, even if you experience some cramping or abdominal discomfort as a result of magnesium supplements, it is just because magnesium has quickly increased gastric motility (passage of food through the body). 

Magnesium citrate, the magnesium formulation used in Natural Calm products, is award winning for a reason. Part of that reason is that it is both easily absorbed, and easy on the digestive system. With normal dosage, you should never experience toxicity as a side effect of taking magnesium. 

Migraine Relief

For many people, migraine relief is their primary reason for taking magnesium — but it can also be a very positive unanticipated side effect.

Magnesium deficiency presents itself in so many ways that it can be hard to officially diagnose. Despite this frustrating fact, research suggests that some people who experience migraines are likely to suffer from magnesium deficiency. 

There’s substantial evidence for magnesium’s potential in treating migraines, with one study by the University of Maryland Medical Centre finding that taking magnesium often could reduce migraine attacks by 41.6%. Other research has spoken to magnesium’s efficacy in treating pain, including migraines, related to menstruation and PMS

Over the years, countless people have approaches us to share their stories of how Natural Calm magnesium has helped to reduce their migraine attacks. In fact, Natural Calm Canada’s founder, Linda Bolton, first discovered magnesium because her sister, Debbie, experienced debilitating migraines for a large part of her life. Debbie tried a vast array of treatments to no avail. Magnesium greatly reduced the frequency and intensity of her migraines, and many others share her experience. 

Over the years, magnesium has been recognized more and more as a safe and natural alternative to allopathic medications. 

It works by preventing the dip in serotonin levels associated with low magnesium, which can be a cause of migraines, as well as relaxing blood vessels and thinning blood to mitigate pain during migraines. In addition, it prevents muscle spasms to reduce pain, and promotes restful sleep, both of which are preventative measures for different types of migraines. 

If you’ve just started supplementing and wonder what happened to your migraines, now you know. Less pain is a fabulous side effect of taking magnesium.

Improved Cardiovascular Health

Maybe you’ve decided to take magnesium for the short-term benefits, but improved heart health can be a side effect.

It’s easy to forget that the heart is simply a muscle. Like so many other muscles in the body, its proper functioning is essential to keeping you healthy and happy. If you’ve read about magnesium and muscles before, you can probably guess where this is going.

Magnesium and potassium work together to stimulate and regulate the muscle contractions that make your heart beat, as well as preventing blockages in the arteries by preventing the buildup of calcium and cholesterol on arterial walls. In conjunction, it also acts as a natural blood thinner, to keep blood running smoothly and effectively through the heart. 

If there’s one thing we know by now, it’s that magnesium is a multitasking mineral. The reason it can be such a helpful supplement to people with a range of different health difficulties is because it tends to attack the problem in multiple ways. The same is true of cardiovascular health, where, in addition to acting as a natural statin and muscle relaxant, magnesium also fights high blood pressure. There is a direct connection between blood pressure and magnesium. As magnesium levels in the body go down, blood pressure goes up. 

Keeping up with your daily magnesium requirements can reduce the likelihood of constriction of the blood vessels, allowing for smooth, healthy blood flow and good cardiovascular health.

If your doctor says your blood pressure has improved, it might be a side effect of taking magnesium!

Pros and Cons of Magnesium Supplements

As with anything that we put in our bodies, it’s important to consider every aspect, good and potentially bad, of magnesium supplementation.

The good news is that magnesium is low-risk, and for most people, the benefits greatly outweigh any negative side effects, which are quite rare. In fact, you might notice several positive but unanticipated “side effects”, like the ones we’ve listed here.

We always recommend that you consult your doctor or naturopath if you have specific concerns related to magnesium and your personal health. 

If you’re like most people, you’re not getting enough magnesium from your diet and could benefit from a high-quality, clinically-proven magnesium supplement like Natural Calm.

Available in five fruit flavours and plain (unflavoured), Natural Calm is a great-tasting magnesium supplement backed by tens of thousands of five-star reviews and multiple supplement awards.

natural calm raspberry lemon flavour

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