Mineral supplements are used by substantial minorities in several national surveys, but adoption varies sharply by country, sex and age. The statistics also show why use, intake, inadequacy and clinical status should be treated as separate measures. This overview covers survey periods from 1988–1994 through 2021–2023, with physiological estimates and biomarker measurements identified separately.
Contents
- How widely mineral supplements are used
- Mineral intake, inadequacy and long-term U.S. trends
- Calcium supplements and bone-related context
- Iron and zinc patterns
- Magnesium, potassium, iodine, selenium and copper
- Safety, absorption and measured outcomes
How widely mineral supplements are used
Survey definitions matter. “Any supplement” includes products beyond minerals, while mineral-supplement or single-mineral measures are narrower. The U.S. historical figures below should therefore not be compared as if they measured exactly the same product category.
In Canada, the 2015 Canadian Community Health Survey found vitamin/mineral supplement use among 38% of men and 53% of women aged 1 and older. The products included calcium, magnesium and zinc. Within the same Canadian survey, use ranged from 26.5% among males aged 14–18 to 67.8% among females aged 71 and older (Prevalence of vitamin-mineral supplement use and associated factors among Canadians). These are descriptive survey results, not evidence that supplements caused any health outcome.
Other country-specific surveys show a different scale. Among Japanese adults aged 20–59, calcium-supplement use was 2.1% and iron-supplement use was 1.4% during 2003–2010 (Personal behaviors including food consumption and mineral supplement use among Japanese adults). In a Swedish middle-aged cohort, mineral-supplement use was 19% among men and 31% among women (The prevalence of anaemia and mineral supplement use in a Swedish middle-aged population). Differences in age structure, survey design, product definitions and national habits limit direct ranking across these results.
The U.S. NHANES III measure of any dietary supplement use was about 40% among people aged 2 months and older in 1988–1994. Multivitamin/multimineral products were used by 22% of the population, while single-mineral calcium use was 6% among females. Iron use was 6%–7% among the reported adolescent and young-adult female groups (Prevalence of leading types of dietary supplements used in the Third NHANES).
More recent U.S. data use a broader any-supplement measure. Among adults aged 20 and older, reported use rose from 51.8% in 2011–2012 to 61.4% in 2021–2023 (Trends in dietary supplement use among U.S. adults between 2011 and 2023). That increase describes supplement adoption overall; it does not establish that mineral-specific use rose by the same amount.
Mineral intake, inadequacy and long-term U.S. trends
An intake below the Estimated Average Requirement (EAR) is a population-level inadequacy indicator, not a diagnosis of clinical deficiency. In U.S. data for 2007–2010, 39% of people aged 4 and older consumed less than the calcium EAR from food and supplements. The proportion was 49% among children aged 4–18 (Calcium – Health Professional Fact Sheet).
Mean calcium intake also differed by whether supplements were counted. Among U.S. adults aged 20 and older, the 2007–2010 analysis estimated 1,083 mg/day from food and beverages for men and 842 mg/day for women. Including supplements, the corresponding means were 1,156 mg/day for men and 1,009 mg/day for women. These averages describe groups, not an appropriate dose for an individual.
The same source reported differences by race and ethnicity in 2009–2012: calcium inadequacy was 47%–48% among non-Hispanic Black and Asian participants, compared with 30% among Hispanic participants and 24% among White participants. Among U.S. adults aged 50 and older, inadequate calcium-intake risk was reported as 11.6% higher below a household income of $20,000 in the 2007–2014 data. These comparisons are descriptive and do not prove that income itself caused the intake difference.
Long-term U.S. intake trends show that different minerals can move in opposite directions. From 1999 to March 2020, adult calcium intake from food, beverages and supplements rose from 0.94 to 1.02 g/day. Magnesium intake from all sources rose from 308.07 to 321.85 mg/day, while iron fell from 19.17 to 16.38 mg/day and potassium fell from 2.65 to 2.50 g/day (National trends in nine key minerals intake). These are intake trends, not proof that supplement use caused the changes.
| U.S. adults aged 20+ mineral intake | Earlier value | Later value | Period |
|---|---|---|---|
| Calcium, all listed sources | 0.94 g/day | 1.02 g/day | 1999 to March 2020 |
| Magnesium, all sources | 308.07 mg/day | 321.85 mg/day | 1999 to March 2020 |
| Iron, all sources | 19.17 mg/day | 16.38 mg/day | 1999 to March 2020 |
| Potassium, all sources | 2.65 g/day | 2.50 g/day | 1999 to March 2020 |
In another U.S. NHANES analysis published in 2012, more than 14% of adults had inadequate usual intakes of calcium and magnesium even after supplement use was included. Supplement users had lower inadequacy prevalence than nonusers, but this association does not establish causation (Dietary supplement use is associated with higher intakes of minerals from food sources).
Calcium supplements and bone-related context
Calcium is the most extensively quantified mineral in the supplied U.S. supplement trends. About 22% of U.S. men, 32% of women and 4%–8% of children take calcium-containing supplements, according to the Office of Dietary Supplements summary of NHANES sources (Calcium – Health Professional Fact Sheet).
Among U.S. adults, supplemental calcium at or above the EAR rose from 2.5% in 1999–2000 to 4.6% in 2013–2014, after reaching 6.7% in 2003–2004. Supplemental calcium at or above the Tolerable Upper Intake Level (UL) peaked at 1.2% in 2007–2008 and was 0.4% in 2013–2014 (Trends in calcium supplementation, NHANES 1999–2014). The study also found higher supplemental calcium intake among women, non-Hispanic White adults and adults over 60 in every period from 1999 through 2014.
| Calcium supplementation measure | Result | U.S. period |
|---|---|---|
| At or above the EAR | 2.5% to 4.6% | 1999–2000 to 2013–2014 |
| Peak at or above the EAR | 6.7% | 2003–2004 |
| At or above the UL | 0.4% | 2013–2014 |
| Peak at or above the UL | 1.2% | 2007–2008 |
The physiological context is substantial: about 98% of total body calcium is stored in bone. An ODS-cited estimate says about 30% of postmenopausal women in the United States and Europe have osteoporosis, and at least 40% of those women develop a fragility fracture. These are estimates and physiological context, not findings that calcium supplements alone prevent fractures.
Iron and zinc patterns
Iron statistics combine supplement adoption, intake adequacy and deficiency burden. The World Health Organization estimate cited by ODS attributes about half of 1.62 billion worldwide anemia cases to iron deficiency, or approximately 810 million cases (Iron – Health Professional Fact Sheet). Adults typically contain 3–4 g of elemental iron, most of it in hemoglobin. Heme iron contributes about 10%–15% of total iron intake in Western populations.
The Swedish middle-aged study found that 70% of women were below recommendations for iron, 60% for zinc and selenium, 35% for magnesium and 21% for calcium. Among men, the reported below-recommendation ranges were 33%–47% for zinc, selenium and magnesium, compared with 5% for calcium and iron. The median calcium contribution from Swedish mineral supplements was under 110 mg/day, while iron supplements contributed about 45% of total iron intake among Swedish iron-supplement users. Anemia prevalence was 3% in Swedish premenopausal women and under 2% in postmenopausal women (The prevalence of anaemia and mineral supplement use).
These results illustrate why deficiency burden and supplement prevalence are different metrics. A group can have a high proportion below a recommendation without the survey proving clinical deficiency, and supplement users can differ from nonusers in diet or health behavior.
Magnesium, potassium, iodine, selenium and copper
Magnesium status is often described with both intake and biomarkers. Adults contain about 25 g of magnesium, with 50%–60% in bone. Normal serum magnesium is 0.75–0.95 mmol/L, while hypomagnesemia is below 0.75 mmol/L. Healthy adults excrete about 120 mg of magnesium in urine per day (Magnesium – Health Professional Fact Sheet). These physiological estimates and reference definitions should not be interpreted as personal testing guidance.
For potassium, a 175-pound adult contains about 140 g, equivalent to 45 mmol/kg body weight, and about 90% of ingested potassium is absorbed. Normal serum potassium is 3.6–5.0 mmol/L; hypokalemia is below 3.6 and hyperkalemia above 5.0 mmol/L (Potassium – Health Professional Fact Sheet).
U.S. iodine measurements provide both intake and urinary status. Foods sampled in the Total Diet Study from 2008–2012 supplied an estimated average of 216 mcg/day, with a range of 141–296 mcg/day. In NHANES 1999–2004, 28%–29% of U.S. adults used iodine-containing supplements. Median urinary iodine was 164 mcg/L among NHANES participants aged 6 and older in 2007–2008, and 119 mcg/L among U.S. women of reproductive age in 2007–2014 (Iodine – Health Professional Fact Sheet). More than 90% of dietary iodine is excreted in urine.
Mean serum selenium was 12.7 mcg/dL among U.S. males and females aged 8–80 in NHANES 2011–2016. In healthy people, serum selenium of at least 8 mcg/dL is usually considered sufficient for selenoprotein synthesis (Selenium – Health Professional Fact Sheet). In low-selenium areas of China associated with Keshan disease, cited adult average intakes were no higher than 10 mcg/day, while at least 20 mcg/day protected adults in the cited evidence. A 2018 meta-analysis of 41 studies found selenium supplements reduced Keshan-disease risk by 86%; this is a specific evidence base and not a general outcome estimate for all supplement users.
Average dietary copper intake was about 1,400 mcg/day for men and 1,100 mcg/day for women. Average adult total-body copper was estimated at 50–120 mg, with about two-thirds in the skeleton and muscle (Copper – Health Professional Fact Sheet).
Safety, absorption and measured outcomes
Product labels show how much mineral is delivered, but label amounts are not the same as measured health outcomes. Many U.S. women’s multivitamin/mineral supplements provide 18 mg of iron, or 100% of the Daily Value. Many iron-only supplements provide 65 mg, or 360% of the Daily Value (Iron – Health Professional Fact Sheet). For potassium, multivitamin/mineral products typically provide about 80 mg, and most potassium-only supplements contain up to 99 mg (Potassium – Health Professional Fact Sheet). Calcium-carbonate antacid pills or soft chews provide about 270–400 mg per pill (Calcium – Health Professional Fact Sheet).
Absorption also varies by mineral and product. A 2016 dose-response trial found about 94% absorption of supplemental potassium gluconate, but that specific result does not apply automatically to every potassium product or population. The body absorbs up to about 90% of selenium from common supplemental forms. These are absorption measures, not proof of a clinical benefit.
The available evidence therefore supports several distinct reporting layers: adoption surveys, usual-intake comparisons, EAR-based inadequacy estimates, product-label amounts, physiological estimates, biomarkers and selected trial or meta-analysis outcomes. Survey associations do not prove causation; intake below an EAR is not clinical deficiency; and biomarker or physiological estimates are not personal medical advice. The reviewed evidence does not establish a credible mineral-supplement market-revenue series, so no market-size forecast is asserted.