Are you being woken up at night often with muscle cramps in your legs? Or perhaps you get a sudden cramp walking and it stops you in your tracks? Magnesium deficiency is a common nutritional deficiency which can cause muscle cramps.
I get a lot of questions from my patients about why they are getting random muscle cramps in their legs. It disturbs their sleep and can become an annoyance. Muscle cramping has a number of causes. Magnesium deficiency would be one of the major causes you would consider.
Roles of Magnesium
Magnesium is a vital mineral you need for your body. The following are a few roles magnesium is involved in:
- Bone health. Magnesium works with vitamin D and vitamin K2 to balance calcium levels.
- Energy production. A deficiency in magnesium can cause fatigue.
- Cell communication. Magnesium is involved with nerve signals and muscle contraction. (1)
- Maintaining blood sugar levels (magnesium deficiency linked with diabetes)
- Maintaining blood pressure (magnesium deficiency linked with high blood pressure)
Magnesium plays an important role in controlling muscle contraction. If you have low levels of magnesium, muscles will contract or tighten up. (1) This can result in muscle cramps. Magnesium deficiency is very common, at least in Canada, the U.S., and likely other industrialized countries. Eating food high in magnesium as well as supplementing with magnesium can be important in solving muscle cramps.
Why is magnesium deficiency common?
About 50% of the Canadian population are deficient (below estimated average requirement) in magnesium. (2)
There are a number of reasons many people are deficient in magnesium. In part, there is some proof soil has been depleted of magnesium. As well, people aren’t eating a diversity of wild plants that our ancestors used to eat. The cultivated plants we eat today have less magnesium in them.
There is a lack of magnesium intake in our diets. Most people in the modern industrialized world are eating too many processed foods which are low in magnesium. Even people that eat a nutrient dense diet like the Paleo diet may not reach the recommended daily intake (RDA) of magnesium. Anti-nutrients, such as phytates, are present in many foods that contain higher levels of magnesium (nuts, seeds, dark leafy greens, and legumes). Phytates decrease the absorption of magnesium.
There are also certain conditions that will cause magnesium deficiency:
- Gut problems where absorption of nutrients will be decreased. (SIBO, heartburn/GERD, IBD)
- People taking PPIs (proton pump inhibitor drugs) for heartburn/GERD. If you are taking PPIs, make sure you aware that you won’t be able to digest and absorb nutrients from food as well.
- If you have diabetes, kidney problems, you’re an alcoholic or are taking diuretic drugs, you will excrete more magnesium because of increased urination.
- A high calcium supplement intake can be a problem for magnesium status. Research shows calcium supplements are not beneficial. In fact, they are harmful and increase the risk of heart attacks, strokes, prostate cancer, kidney stones, and joint and muscle pain. (2, 3, 4)
Symptoms of Magnesium Deficiency
Magnesium deficiency can cause several symptoms:
- Muscle cramps
- Irregular heart beats (arrhythmias)
- heart disease
- premenstrual tension syndrome
- type 2 diabetes
- metabolic syndrome
How to increase your magnesium levels
Even if you are aware of how to get magnesium from food and supplements, you may not be getting enough. The RDA for adult men is 420mg/day and 320mg/day for adult women. Keep in mind the RDA is the value needed to prevent acute deficiencies. For optimal ranges (to keep your body and mind functioning well), you should be getting 500-700mg/day from a combination of food and supplements.
Include nuts and seeds in your diet. Pumpkin seeds and almonds are examples that are higher in magnesium. However, nuts and seeds have phytates in them meaning that you’re not going to absorb all of the magnesium in those foods. Your could the soak nuts and seeds overnight and then dry them before consuming them. The soaking breaks down the phytic acid and allows for better absorption.
Other foods high in magnesium include dark leafy greens (spinach and chard), molasses, dark chocolate, and bananas. Dark chocolate might be one of the easiest foods to consume to get magnesium without any preparation. YAY! The process of making chocolate breaks down some of the phytic acid.
Legumes are also a good source of magnesium if you can tolerate them. However, because of the phytic acid in legumes, they need to be soaked so magnesium is easier to absorb from them.
As mentioned, about 50% of Canadians are deficient in magnesium (based on RDA ranges). The average American gets less than 250mg/day of magnesium from food which is well below RDA ranges. You are going to need to supplement with magnesium to get to the optimal ranges of 500 – 700mg/day.
Supplement as follows:
- If you’re eating a nutrient dense diet like the Paleo diet and you’re getting a wide diversity of plants in your diet, and you are soaking seeds and nuts, you may only need to supplement with about 200mg/day.
- If you’re eating a nutrient dense diet like the Paleo diet and you don’t feel like you’re eating a wide diversity of plants, and you’re not soaking seeds and nuts, then I would suggest you start at 400mg/day.
- If you’re not eating a nutrient dense diet like the Paleo diet you may want to supplement higher than 400mg/day and even up to 800mg/day.
The dose of up to 800mg/day would not be expected to cause any toxic symptoms. However, I would build up to that dose gradually. A sign of too much magnesium would be loose stools.
Chelated forms of magnesium like magnesium glycinate and malate tend to absorb better. Magnesium glycinate also tends to be good for chronic pain and muscle contraction. So I would recommend this form of magnesium for you to see if it helps with your muscle cramps. I have also included a table below for you to look at regarding the different uses for different types of magnesium supplements.
Speaking of absorption, magnesium absorbs better when taken with protein in your meal. I like taking my whole daily dose of magnesium glycinate with my evening dinner as I find it helps me sleep better.
It should be noted that magnesium can interfere with the absorption of the following drugs:
- Digoxin (heart medication)
- Biphosphonates (osteoporosis)
- Nitrofurantoin (antibiotic)
- certain anti-malarial drugs
Magnesium is a vital mineral your body needs for many functions including nerve signals and muscle contractions. Magnesium deficiency is very common and one of the symptoms is muscle cramps. Even if you eat really well, it’s hard to get optimal amounts of magnesium. Therefore, supplementing with magnesium whether or not you have muscle cramps is important. If you do have muscle cramps, supplementing with 400-800mg/day of magnesium is certainly worth a try.