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4 Little-Known Causes of Restless Legs Syndrome


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Restless legs syndrome is a seemingly simple condition, but the cause is often difficult to pinpoint. Find out four potential contributing factors and how to address them.

dietary causes of rls
Can certain dietary choices cause RLS? Stockbyte/Stockbyte/Thinkstock

Few things are more frustrating than lying in bed at night exhausted, but not being able to fall asleep because of an uncontrollable urge to move your legs. This phenomenon, known as restless legs syndrome (RLS), affects between 4% and 29% of adults in Western populations, and is a major contributor to sleep loss. (1, 2)

Pinpointing the cause of RLS has been an active research topic for years, but the condition is still not fully understood. The symptoms have been convincingly linked to impaired dopamine function in the brain, but the cause of this dysfunction is still being explored.

In this article, I’ll review four factors that could contribute to RLS, as well as steps you can take for improving your symptoms.

1. Systemic Inflammation and Immune Dysregulation

Restless legs syndrome has been associated with numerous conditions involving systemic inflammation and immune dysregulation. (3) One review paper published in 2012 investigated health conditions that were reported to cause or exacerbate RLS symptoms, and found that 95% of the 38 different health conditions that were strongly associated with RLS have an inflammation or immune component. (4) These conditions include Parkinson’s disease, multiple sclerosis, ADHD, Alzheimer’s disease, Celiac disease, Crohn’s disease, rheumatoid arthritis, sleep apnea, diabetes, and depression.

As further evidence, an elevated blood level of C-reactive protein (a marker of systemic inflammation) has been associated with increased RLS severity. (5) A small crossover trial found that a hydrocortisone infusion, which reduces systemic inflammation, reduced RLS symptoms. (6)

Researchers have proposed three potential mechanisms to explain the association between RLS and inflammatory or autoimmune states: direct autoimmune attack on the nervous system; genetic factors that could predispose an individual to RLS and be triggered by inflammation or autoimmunity; and iron deficiency caused by inflammation, which I’ll talk more about below.

What to do: If your RLS is a symptom of underlying systemic inflammation or immune dysregulation, the goal should be to find and treat the root cause. As I’ve mentioned many times in the past, gut infections are often the culprit—even if you don’t have noticeable digestive symptoms—so get your gut tested.

If you already have a diagnosed inflammatory or immune condition such as those I mentioned above, the best first step you can take is to adopt a “low-inflammatory” diet and lifestyle. This means eating a nutrient-rich, low-toxin diet based on whole foods; getting enough sleep every night; prioritizing stress management; and incorporating regular movement into your day.

You can also check out the bonus chapter about autoimmune disease from my book, as well as explore other information on my site about reversing autoimmune disease, the autoimmune protocol, the role of the microbiome, and alternative therapies such as LDN.

Do you have restless legs syndrome? Find out what might be causing it, and what to do.

2. Small Intestinal Bacterial Overgrowth (SIBO) and IBS

Some of the more recent research on restless legs syndrome has focused on a connection with small intestinal bacterial overgrowth (SIBO) and IBS, which is often caused by SIBO. One study found that 69% of RLS patients also had SIBO, compared with only 28% of controls. (7) They also found that 28% of RLS patients had IBS, compared to only 4% of controls. And according to the 2012 review I mentioned in the previous section, 32% of the 38 conditions associated with RLS are also associated with SIBO. (8)

A strong association between SIBO and RLS doesn’t mean that SIBO is causing RLS in these patients. But a few trials have found that in patients with both SIBO and RLS, their RLS symptoms improve after being treated for SIBO. (9)

For example, one double-blind, placebo-controlled study reported that treatment with the antibiotic rifaximin—the standard treatment for SIBO—significantly improved RLS symptoms in patients with both conditions. (10) This, of course, does suggest a causal link between SIBO and RLS.

What to do: If you have both RLS and SIBO, the best option would be to find a functional medicine practitioner who has experience dealing with SIBO and get treated. That said, two steps you can try on your own are a low-FODMAP diet and probiotics. Low-FODMAP diets reduce the amount of fermentable carbohydrates that “feed” bacteria in the small intestine, and a couple studies have shown that probiotics can be as effective as antibiotics for treating SIBO. (11, 12) I’ve found the probiotics S. boulardii (a beneficial yeast), and MegaSporeBiotic to be helpful.

One important note about low-FODMAP diets, however, is that it’s generally not a good idea to stay on one indefinitely. Low-FODMAP diets eliminate sources of prebiotics, which can improve symptoms by starving pathogenic bacteria, but can also starve your beneficial bacteria. The best approach is to follow a low-FODMAP diet until symptoms subside (and your SIBO breath test is normal), and then gradually re-introduce prebiotic foods (or supplements) to support your gut microbiome.

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3. Vitamin D Deficiency

As I mentioned in the introduction, one of the most-researched theories about the cause of restless legs syndrome is impaired dopamine signaling, which has led to the conventional treatment of RLS by dopamine agonists (i.e. chemicals that can bind to and activate dopamine receptors). Unfortunately, these treatments can become less effective over time, and can even result in a worsening of symptoms.

And while replacing neurotransmitters might be an effective way to manage symptoms in the short term, the goal should be to figure out why dopamine signaling is impaired in the first place.

This is where vitamin D comes into play.

The role of vitamin D in dopamine signaling is only beginning to be investigated, but some evidence indicates that vitamin D could play an important role by increasing levels of dopamine and its metabolites in the brain, as well as protecting dopamine-associated neurons from toxins. (13)

RLS has been associated with vitamin D deficiency in several studies, and disease severity has been inversely correlated with vitamin D levels. (14, 15, 16) One study has also found that vitamin D supplementation improved the severity of RLS symptoms. (17)

What to do: If you have RLS, one of the easiest first steps you can take is to get your vitamin D levels tested. A good range to shoot for is typically between 25-50 ng/mL, but if you have an autoimmune disease or another chronic health condition, I prefer to bring vitamin D levels up to 35-60 ng/mL. One way to supplement vitamin D is cod liver oil; I recommend extra-virgin cod liver oil. You can also take a D3 supplement. And of course, you should get regular sun exposure to bring your vitamin D levels up naturally.

4. Iron Deficiency

Iron deficiency isn’t exactly a “little-known” cause of restless legs syndrome; in fact, it’s probably one of the most well-researched areas relating to RLS. Iron is required for proper dopamine signaling, but its role is much better established than that of vitamin D, and it’s pretty clear that iron deficiency in the CNS can cause RLS symptoms by impairing dopamine function. (18)

Several studies have found that low iron levels in the cerebrospinal fluid and in the brain occur more frequently in patients with RLS compared with matched controls. (19, 20) And this difference isn’t always reflected in serum ferritin levels.

Other abnormalities in iron metabolism have also been observed in RLS patients, and many conditions that increase the risk of RLS (including pregnancy and end-stage kidney disease) are known to cause iron insufficiency. (21, 22)

Further, iron supplementation significantly improves or even eliminates the symptoms of RLS in many patients. For example, RLS patients with low-normal serum ferritin experienced significant improvements in their RLS symptoms after 12 weeks of iron supplementation. (23) And oral iron was as effective for treating RLS as pramiprexole, a dopamine agonist, although the response rate for both treatments was relatively low (46.7%). (24)

The tricky thing about iron deficiency is that the solution is often not as simple as taking an iron supplement. Iron deficiency is frequently secondary to SIBO, gut infections, or other inflammatory states, which explains at least in part the association between RLS and these conditions. Iron deficiency caused by infection or inflammation is mediated primarily by the hormone hepcidin, which at high levels can decrease serum iron and reduce iron absorption from the GI tract. (25)

One cause of increased hepcidin levels is the production of IL-6, an inflammatory cytokine present in most inflammatory diseases. Another cause of increased hepcidin levels is the presence of lipopolysaccharides (LPS), which are components of gram-negative bacteria that can enter circulation as a result of SIBO or other gut infections. Thus, increased levels of circulating IL-6 or LPS can result in iron deficiency, and subsequently, RLS.

What to do: If you have RLS and iron deficiency, the first step is to identify why you’re iron deficient. If the cause is blood loss (such as from heavy menstruation in women) or dietary insufficiency (such as in vegetarian or vegan diets), increase your consumption of iron-rich foods such as liver and red meat. You can also consider an iron supplement; I recommend Proferrin ES and bovine ferritin, because they are better absorbed and better tolerated than plant-based iron supplements. 

However, if the cause is SIBO or a gut infection, increasing iron intake can often make matters worse by creating an environment that promotes pathogen growth and inflammation. (26, 27, 28) For this reason, it’s best to address the gut before (or at least concurrently with) adding iron supplements.

As you can see, restless legs syndrome is complex, and several factors could come into play when trying to figure out the cause. As with many other health conditions, RLS is best seen as a symptom which signals that something else is amiss, and it’s necessary to dig deeper to find out the root cause, and how to treat it.

If you suffer from restless legs syndrome, I hope this article helped clarify what might be causing it.

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Join the conversation

  1. I control my restless legs with magnesium and thyroid (T3 as liothyronine): I need both. I take them when I get the RLS, always at night. I do have a lot of inflammation- allergies and sensitivities, and found from dealing with depression that I am probably low in Dopamine ( bupropion,= welbutrin helps) and suspect that I have SIBO. I basically agree with what Chris wrote, I just have another way of dealing with RLS, not necessarilly the best way.

  2. My RLS was diagnosed in 1996 along with PLMD (periodic limb movement disorder) and an apnea (despite being 7% body fat at the time). At that time I was still a very active athlete (had a major hip injury that made be less active), but despite working out 25 to 30 hours a week, I couldn’t sleep. Per the sleep studies done in 1996, I had over 150 disruptions per minute and most of my “sleep” was stage 1 and stage 2 level sleep. I was put on Permax, and then about six or so years later switched to requip after permax had been shown to cause heart valve leaks. I took Requip until about 2012. I couldn’t sleep without meds.

    Towards the end of 2012 I switched my diet to a ketogenic one. Since making this switch, I no longer take requip and can get deep sleep without any meds. Prior to this change of diet, I was an on and off again vegetarian. I was also briefly vegan for about two years. During the times before 2012 that I wasn’t vegetarian or vegan, I followed a low fat diet since low fat high carb diets were what athletes typically followed.

    So some of what I experienced may coincide with vitamin D and iron deficiencies, but I’d suggest that “good” fats play an essential role in a properly functioning neurological system which would be consistent with research that shows ketogenic diets being useful for other neurological maladies including epilepsy, and parkinson’s disease.

      • I’m not absolute, but yes I have drastically reduced my carbs. My stomach is Italian, so I can’t cut out really good pasta completely. I have though cut out most other grains and especially simple carbs (sugars). But again, once in a while, I’ll indulge at a restaurant with dessert.

    • My husband and I have been eating VLC/HF for about 6 years now. One surprising effect of this for both of us has been a really marked improvement in our reflexes. My working theory is that by eating lots of sat fat and cholesterol and choline, we have given our bodies the wherewithal to add myelin to our nerves. No proof, but we both noticed this independently.

  3. 25 years ago I was asking my doctor about my leg symptoms, and he kept thinking I was talking about cramps and I had to say no, and tried to explain this odd condition. Then later as I came in for another visit he seemed excited to tell me he found out what I was talking about, and that it was called Restless Leg Syndrome. I was so happy to have a name for it and to feel like it was something legitimate, even if he didn’t have any answers for me. This makes me wonder if this condition has been around forever or if it is rather new.

    Over the years I’ve tried taking iron or other things that may have helped some, but this past year I got testing and found out I am gluten sensitive and had some gut dysbiosis, along with nutritional deficiencies including iron, Vit D and Vit B12. My restless legs have gone away (along with other things) after treating all of these, so I cannot pinpoint which might have been the biggest influence. I’m just so thankful to finally have it gone!

    • Well, Donna, I know knowledge of RLS has “been around” for at least 75 or so years, as I’ve had RLS since I was a boy and I’m now 84 years old. I believe, at least in my experience, it is caused by a magnesium deficiency. Recently a health counselor advised me to begin a dermal magnesium therapy with a magnesium spray. Twice daily I spray magnesium on my legs and feet and upper body. The resulting experience has been more energy and no more RLS. I also occasionally take a epsom salt bath or foot soaking with mineral salts. This gives great relief as well.

  4. I have had tension and aches in my calves for more than 5-7 years. The pain would be lessened if I stretch them or tie a cloth around them tightly. Does this sort of pain qualifies as RLS? Does anyone know?
    My nutritionist recently recommended that it may be muscle spasm caused by magnesium deficiency. I have been taking Mixed Mg supplements and it has helped, although the problem is not 100% gone. I also have h-pylori and very low levels of B12 and vitamin D. Any suggestions are welcome.

    • I have a neighbour who had cramping in her calves at night. She was told she was low in potassium and should eat bananas. This worked for her.

    • Aadd you sound like me before I was diagnosed with hashimotos thyroiditis. Be careful with h-pylori, I hope you are treating it. I believe it helped trigger autoimmune disease in me. A magnesium deficiency can take a while to respond to oral supplementation. Also, low levels of D will put you at risk for autoimmune disease. Chris’s linked supplement looks good. My achilles tendons get really tight when I am hypothyroid. Perhaps you should do a thyroid panel with your nutrtionist?

  5. I do have RA, and have also had restless legs for several years. I had read that taking magnesium would help, but I did supplement to no avail. I was getting it every night in addition to involuntary twitches in my arms, legs and even in my torso. I then read that I should use magnesium spray instead. I figured i would try it. Within 2 days of using as directed, all RLS stopped, plus the twitches! I was amazed. Sometimes I would forget to use it, ans sure enough, they would start to come back.
    Just my experience, but if you suffer from RLS, I think you would try anything, as I did.

  6. I’m grain, dairy, soy, corn, sugar free among others. I found that if soy creeps into my diet, I would experience RLS. Corn by products can also trigger it for me.

  7. I had persistent RLS for years. When I went gluten free, the symptoms diminished substantially. Now also grain free, it is completely gone!

    • Mine disappeared when I removed gluten too! Didn’t even realize it at first. RLS comes back if I gluten myself. HATE that feeling!!!

    • Yes, whenever I eat gluten. Or even if I binge on too much sugar. I notice a big change. I’m still working on cleaning up my food choices. But awareness is half the battle.

    • Many on here mention they think gluten is causing their RLS. It can be a contributing factor because it can cause inflammation in the gut for some, which can kill beneficial bacteria and interfere with nutrient absorption. And many foods containing gluten also contain phytic acid which binds to the magnesium preventing absorption.

      There’s a lot of good information in the following linked article for everyone, not just people concerned about gluten in their food:

      Most of us have a magnesium deficiency (over 80% in the US) and glyphosate (Monsanto’s RoundUp™) residues in food contribute greatly to gut dysbiosis which interferes with nutrient absorption. (and immune function)

      If you don’t think you have a problem with glyphosate because you avoid GMOs, think again. Or better yet, read this article:

      Conventional farmers are using glyphosate as a desiccant (drying agent) for crops like wheat, oats, soy, barley and rye. Just before harvest, they literally douse the plant with glyphosate resulting in residues in our food that are frighteningly high. And these are not even GMO foods!

  8. The only thing I have found to relieve my RLS is to ride my bike a mile or more in the evening. When the weather is not agreeable I use my airdyne. If I fail to do this I will be getting out of bed later to do it.

  9. I have the worst case of restless legs arms hands and feet-been on every med out there and the only thing that helps is tramadol and 3 mag.(the good kind) I have it 24-7 as soon as I start to relax it acts up.I’m 58 and my doctor said I have the bloodwork of a 20 year old-I’m also not lacking anything,not even a pound over weigh-I exercise every day-I do have allergies and I’m in remission for interstitial cystitis

    • My RLS symptoms are mostly in the past, thanks to going gluten free and magnesium supplements. If my legs start to act up, I will rub magnesium oil on them and that does the trick.

    • I guess everyone has this different and different things help-I’m still looking-thought it might be food but I hardly ate for a week and was still horrible,not lacking anything,always hydrated-blood work is wonderful,very healthy,but this is such a big problem in my life-started with the legs and years later hit the arms,hands and feet.Not the typical nighttime problem,it’s 24-7 All I can say to everyone is hang in there!

      • Maybe you should take another look. I’m reading that for neurological health B12 should be around 1000 units. Some sources I’ve read say between 700 – 800 pm/l and anyone with levels under 450 especially if supplementing should be flagged. In Canada we’re told were fine if we’re over 133……….sigh.

    • Not in my case-Since everyone is different I doubt we will ever know what the real problem is.I would say something in the brain

  10. After minor surgery I was over prescribed Percocet, and had withdrawal symptoms when I stopped, which included RLS, along with goosebumps (several times a minute) and some serious psycopathy. I wonder what about drug withdrawal causes RLS.

  11. About two months after my treatment with Chris, my husband commented that I wasn’t kicking at night. I had YEARS of RLS and my mother and sisters did too. When he mentioned it I suddenly realized I was no longer miserable at night before going to be and in bed. It’s been four years and I’ve only had two very mild episodes. Chris and I worked through a LOT so I can’t pinpoint the exact reason I no longer have RLS, but I often contribute it to B12 deficiency. I think the two recurrences were when I was not getting enough B12. BUT, I did also heal my gut through work with Chris, am on a continued diet which reduces inflammation AND built up my vitamin D, so it really could be any of those things. All I know is it’s really a miracle. I only wish I could get my mother and sisters to go to my extreme dietary measures to heal their RLS too!

  12. I have a son whose restless legs are positive acrobatic sometimes.
    He’s also got OCD and possibly Tourette’s, an apparent consequence of glutamate processing issues. Are you aware of any research connecting glutamate dysregulation and restless leg syndrome?
    I feel like this is an area that is poorly understood by science. I can say categorically that cutting out high-glutamate processed foods and adding glutathione-boosting NAC has dramatically helped all of these conditions, including RLS. I think they all stem from the same cause.

    • Hi,
      Please get a strep titre if you have not already. My daughter emerged with RLS and so e OCD symptoms after many, many bouts of serious strep with Scarlet fever. She also has Celiac too.

  13. I was ill with flu last year and did not eat for a few days. As I was getting better that evening I had a large bowl of tortilla soup from a local restaurant. My first meal for 3 days. That night I could not sleep and my legs were twitching and all over the place. I have since discovered that MSG is the trigger for these symptoms. The tortilla soup was laden with msg. I am now very careful to look out for all the different forms of MSG as they definitely affect me badly.

  14. After suffering with rls for 40 years, I finally figured out 300 mg of mag at bedtime does the trick. God bless magnesium.

    • I also found relief from RLS by increasing my magnesium supplementally. Lots of other issues improved or disappeared as well. I concluded that I had absorption problems that resulted in low magnesium levels, the cause of which was SIBO for me.

    • For me, it’s Magnesium also. I take a lot, and for some reason cannot hold onto it so until I figure out what’s underlying the problem with RLS which can lead to muscle cramps leading to migraine from muscle cramps in my neck, shoulders and head, I keep taking Mg.

      • I take Magnesium Malate in the morning and citrate & glutamate in the evening. If you take the right types of magnesium you can become magnesium replete.

      • If you’re taking a readily bioavailable type of magnesium, have no gut issues, but need to take high levels of magnesium to maintain body levels, then look at your sugar (and simple carbs) consumption. Because magnesium is required in several enzymatic functions related to sugar metabolism, high consumption can contribute to a greatly increased need for this mineral, competing with your muscles for it.

  15. Though I am not sure exactly what defines RLS, I have less problem with my legs moving at night than I do cramping in my calves, especially my right one. During the day, I have to sit a lot, and it is then that my legs are very restless. I have had to become focused on my absent-minded habit of bouncing my leg(s) up and down. I am guessing this is a release of unspent energy, but I wonder how it contributes to the tension that I develop in my muscles. I have great difficulty finding a comfortable position to sit, and the restlessness is shown in the leg movements. I have been this way as long as I can remember, and though transdermal mag application as well as high dosage oral supplements, it remains a problem. I developed a lot of varicose and spider veins in my leg from the years when I worked on my feet all the time, and I figure that has something to do with the increase in cramping. These tend to hit me in the morning, an hour or two before I would normally get up, and so break up my good sleep. An application of mag oil spray on the site will calm them pretty quickly, but recently I am finding that there is tension in the calf muscles during the day as well. I do react to FODMAPS and have been following a low fodmap primal diet for some time, now, but lack the money to pursue true healing. I agree that restricting the diet this way long term can cause more problems, and I appreciate this article and the light it sheds on the issue. I have not had vitamin D levels tested, so that will be a good place to start, it seems.

    • Hey, sounds like me! My podiatrist was very helpful — pointing me in the right direction with orthotics, shoes that support my legs properly and a daily routine of stretches (many times a day). ROLFing massages have helped a lot, too! My issues are structural/biomechanical primarily, although internal imbalances of course contribute to the whole picture.

  16. For a couple of years, I’ve been focusing on healing my digestive system, balancing my gut biome, adding magnesium throughout the day in different ways (and forms,) supplementing with B vitamins + amino acids for gut and brain health, incorporating lifestyle changes to diminish stress. All have improved the quality of my life, but it was not until I started taking LDN a few months back that my RLS symptoms were completely resolved, along with the majority of my chronic depression and anxiety. I have Hashi’s and a family history of Parkinson’s. I’m loving life again! Thanks to Chris, for making me aware of LDN and to my DO for prescribing it.

  17. I’m 8+ months pregnant and have had increased restless leg symptoms; I asked my doctor (who I do love), but the best tip she could give was making sure I was drinking plenty of water…. however low iron makes complete sense as well for someone pregnant!

    • Michelle, I had horrible RLS through both of my pregnancies, and taking iron supplements completely eliminated it. The effect was pretty well immediate–if I’d taken the iron that day, I wouldn’t have RLS that night; if I skipped a day on the iron, the RLS would come back that night. After giving birth, the symptoms almost disappeared, so it’s not a permanent thing!

      • Wonderful to hear, thanks for sharing! I had RLS just very minorly before pregnancy. I am eating (a small amount) of liver every few weeks and know that helped light-headedness in second trimester. Maybe I’ll try an iron supplement instead or in addition.

        • Just do be careful with the iron being so close to your due date, as it can be constipating and constipation is typically already a major issue in the few days postpartum as your body figures out how to get back to normal. I would go easy on the iron in the week or so before your due date.

      • I started getting RLS wheni was pregnant with my 1st daughter 34 years ago. It got better after she was born until I got pregnant again two years later. My experience – it has continued to get worse the rest of my life. I have tried everything and found nothing that helps. Surviving on very little sleep.

    • I remember I had horrible cramps in my calves when in late pregnancy. My husband needed to help me stop the cramps. Usually I could do it myself. Not then.

      I know magnesium helps me reduce cramps now.

  18. I think I have finally figured out what causes or contributes to my RLS. Caffeinated drinks (even green tea counts) after 6pm and/or chocolate and other sweets with cocoa all act as stimulants. After I stopped consuming those in the evenings, my symptoms improved dramatically.

    Also a liver cleanse works wonders and results in the most sound and comfortable sleep.