A claim you hear on longevity podcasts
The claim checked: Muscle cramps, twitching, insomnia and anxiety are symptoms related to magnesium Hear it at 1:13
Two observational studies linked lower magnesium intake or blood levels to poorer sleep, one in fibromyalgia patients; neither tested cause. None in this set looked at anxiety, cramps or twitching.
Computed from 2 studies that test this point, each judged by two readers, in full. Fewer than 3 sources so far. 5 more studies are waiting for a full read and do not count yet.
“so many symptoms we didn't even think of as being related to magnesium but they are like muscle cramps or muscle twitching insomnia anxiety irritability sensitivity to now loud noises palpitations in your heart”
None.
other primary study · 2022
“Mg intake was associated with both sleep outcomes in this longitudinal analysis.”
Association of magnesium intake with sleep duration and sleep quality: findings from the CARDIA study. Sleep
Who: young American adults aged 18-30 at baseline (1985-86) in the CARDIA cohort, four US sites
PMID 34883514
trial or observed group · 2025
“Moreover, lower serum magnesium levels were found to be associated with poorer sleep quality and more severe clinical symptoms.”
Serum magnesium levels and their association with sleep quality and disease severity in fibromyalgia syndrome: An observational cross-sectional study. Medicine (Baltimore)
Who: 82 women aged 18-65 with fibromyalgia syndrome at a single Turkish tertiary outpatient clinic, not taking magnesium supplements, PPIs or diuretics
PMID 40696633
None.
All six studies found many Americans eat less magnesium than recommended: 45% in one national survey, 40% to 61% of non-supplement users in another.
Computed from 6 studies that test this point, each judged by two readers, in full. 4 more studies are waiting for a full read and do not count yet.
trial or observed group · 2011
“The percentage of individuals aged ≥2 y with total usual nutrient intake, including that from foods and dietary supplements, falling below the EAR was considerable for vitamin D (70%), vitamin E (60%), calcium (38%), vitamin A (34%), vitamin C (25%), and magnesium (45%) ( Table 1 ).”
Foods, fortificants, and supplements: Where do Americans get their nutrients? J Nutr
Who: nationally representative U.S. population aged 2 y and older (NHANES 2003-2006), excluding pregnant/lactating women
PMID 21865568
other primary study · 2017
“Importantly, the prevalence of intakes below the EAR for these shortfall nutrients was high among non–supplement users, ranging from 91% to 99% for vitamin D, 40% to 61% for magnesium, 32% to 57% for vitamin C, 18% to 68% for calcium, and to 2% to 31% for folate, across sex and PIR groups.”
Total Usual Intake of Shortfall Nutrients Varies With Poverty Among US Adults. J Nutr Educ Behav
Who: Nationally representative, nonpregnant US adults aged 19 and older in NHANES 2011-2012 with complete poverty and diet data
PMID 28539198
other primary study · 2024
“Over the time studied, United States adults underconsumed vitamins A, C, D, E, and K; calcium; potassium; magnesium; and choline, even when DSs intake was included.”
Temporal changes in micronutrient intake among United States Adults, NHANES 2003 through 2018: A cross-sectional study. Am J Clin Nutr
Who: nationally representative US adults aged 19+ (non-pregnant, non-lactating) in NHANES 2003-2018
PMID 38373695
other primary study · 2017
“While there were some differences in intakes from food alone in dietary supplement consumers and non-consumers, especially in the 19–50 years group, all age groups had greater than 25% of the population with intakes below the EAR for calcium, magnesium, and vitamins A, C, D, and E.”
Contribution of Dietary Supplements to Nutritional Adequacy in Various Adult Age Groups. Nutrients
Who: non-institutionalized US adults aged 19+ in NHANES 2009-2012, excluding pregnant or lactating women
PMID 29211007
other primary study · 2018
“Overall, 83.3% of participants were not meeting the recommended level of dietary magnesium intake, ranging from 78.1% of other ethnic groups to 90.6% of African Americans.”
Ethnic Differences in Magnesium Intake in U.S. Older Adults: Findings from NHANES 2005⁻2016. Nutrients
Who: U.S. older adults aged 65 and over in NHANES 2005/06-2015/16
PMID 30518025
other primary study · 2025
“While seven nutrients showed inadequacy across all demographic groups (vitamin D, vitamin E, calcium, choline, iodine, magnesium, potassium, and dietary fiber), a set of inadequacies characterized each demographic group, indicating that targeted recommendations across the lifespan may also be useful.”
Identification of Priority Nutrients in the US: Targeting Malnutrition to Address Diet-Related Disease Across the Lifespan. Nutrients
Who: US population aged 4 and older in eight age/sex demographic groups, intake from NHANES/WWEIA 2017-March 2020 (pregnancy/lactation from 2003-2006 data and literature)
PMID 40573068
None.
None.
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