Mineral

Boron is a trace mineral that may play a role in bone health, calcium metabolism, and inflammatory regulation. Animal studies suggest boron supplementation can influence bone mineral density and biomechanical properties, particularly in the context of hormonal status, such as estrogen deficiency (PMID 12835499, PMID 34082267). In ovariectomized rats, boron in the form of boric acid increased estrogen-induced urinary calcium excretion but did not significantly alter serum osteocalcin or mineral levels, indicating its effects may be modulated by hormonal environment (PMID 12835499). In rabbits fed a high-energy diet, boron supplementation via drinking water altered bone and teeth mineral composition, with effects varying by chemical form—boric acid, borax decahydrate, and anhydrous borax—suggesting the delivery method and compound type influence outcomes (PMID 34082267). Boron may also affect metabolic parameters, as seen in diabetic rats where boric acid reduced oxidative stress and improved lipid profiles (PMID 29019104). However, human clinical evidence remains limited, and no established Recommended Dietary Allowance (RDA) exists. Current data support potential benefits for bone and metabolic health, but more research is needed to define optimal intake and long-term safety.

Calcium is an essential mineral critical for bone health, muscle function, nerve transmission, and vascular contraction. While calcium supplementation effectively increases bone mineral density (BMD), high-quality evidence shows it does not significantly reduce fracture risk in community-dwelling adults, particularly when combined with vitamin D (PMID 29596263). Some studies suggest modest blood pressure-lowering effects in normotensive individuals, supporting a potential role in primary hypertension prevention (PMID 26126003, 26420598). Calcium supplementation may also improve lipid profiles, with meta-analyses indicating a small but significant reduction in LDL cholesterol (PMID 33226265). However, concerns about cardiovascular safety have emerged: multiple meta-analyses report an increased risk of myocardial infarction and cardiovascular events with calcium supplements, especially without co-administered vitamin D, raising questions about risk-benefit balance (PMID 20671013, 21621353). Dietary calcium appears safer and similarly effective for bone health, suggesting supplements should be used judiciously.

Copper is an essential trace mineral involved in numerous enzymatic processes, including redox reactions, iron metabolism, connective tissue formation, and antioxidant defense. It is a cofactor for enzymes such as cytochrome c oxidase, superoxide dismutase, and lysyl oxidase, which are critical for energy production, oxidative stress protection, and collagen cross-linking (PMID 19874945, PMID 19906252). Copper deficiency can lead to anemia, neutropenia, osteoporosis, and skeletal abnormalities, particularly in individuals receiving parenteral nutrition. While animal and in vitro studies suggest a role for copper in bone metabolism, human evidence remains limited and inconsistent (PMID 34210051). Copper homeostasis is tightly regulated, primarily through intestinal absorption, and excess intake can be toxic due to its redox activity, especially in individuals with genetic disorders like Wilson’s disease (PMID 19906252, PMID 16305470). Serum copper and ceruloplasmin levels are commonly used but unreliable markers of copper status, particularly during inflammation (PMID 19874945, PMID 29927526).

Iron is an essential mineral critical for hemoglobin synthesis, oxygen transport, and cellular metabolism. Iron deficiency (ID) is the most common nutritional deficiency worldwide, affecting over 1.2 billion people, particularly women of reproductive age, pregnant individuals, children, and those with chronic diseases such as heart failure or cancer (PMID 40603791). ID can progress to iron deficiency anemia (IDA), characterized by low hemoglobin, microcytic red blood cells, and fatigue. Treatment involves oral or intravenous (IV) supplementation depending on severity, absorption issues, or underlying conditions. IV iron is effective in patients with malabsorption, inflammatory conditions, or functional iron deficiency, such as in heart failure or cancer, where oral iron may be ineffective (PMID 22925176, 26657161, 26373748). Oral iron is commonly used but can be limited by gastrointestinal side effects and hepcidin-mediated inhibition of absorption, especially with daily dosing (PMID 26289639). Vitamin C co-supplementation does not significantly enhance iron absorption or efficacy in adults with IDA (PMID 33136134), and intermittent dosing (1–2 times/week) appears as effective as daily dosing in children (PMID 36849195). Low-dose iron (20 mg/day) during pregnancy effectively prevents IDA with fewer side effects than higher doses (PMID 12816784).

Magnesium is an essential mineral involved in over 300 enzymatic reactions, including those regulating blood pressure, glucose metabolism, and cardiovascular function. Evidence suggests that magnesium supplementation may improve metabolic health, particularly in individuals with hypomagnesemia or metabolic syndrome. Supplementation has been shown to reduce systolic and diastolic blood pressure, especially in those with baseline hypertension or low magnesium levels (PMID 22318649, PMID 39380547). It may also improve metabolic parameters such as HDL-cholesterol in prediabetes (PMID 36307427) and enhance the metabolic profile in metabolically obese, normal-weight individuals (PMID 24830937). However, not all benefits are consistent—some studies show no effect on insulin sensitivity in type 2 diabetes despite correcting serum magnesium (PMID 37922013). Magnesium also supports vitamin D metabolism, and co-supplementation may enhance cardiometabolic outcomes (PMID 35576873). Overall, benefits are most evident in magnesium-deficient populations.

Phosphorus is an essential mineral critical for bone health, energy metabolism, and cellular function, with approximately 85% stored in bone as hydroxyapatite in dynamic equilibrium with extracellular fluid (PMID 19483271). Regulation of serum phosphate is tightly controlled by parathyroid hormone (PTH), vitamin D, and fibroblast growth factor 23 (FGF23), which collectively maintain calcium-phosphate balance and prevent ectopic calcification (PMID 19483271, 27282935). Chronic positive phosphate balance, particularly in individuals with impaired kidney function, is associated with increased cardiovascular risk, accelerated vascular calcification, and higher mortality, especially in chronic kidney disease (CKD) and dialysis populations (PMID 27282935, 24743045). Dietary phosphate restriction, phosphate binders (e.g., sevelamer, calcium-based agents), and improved cooking methods can effectively reduce serum phosphate levels in hyperphosphatemic patients (PMID 27282935, 25663645, 26141941). In clinical settings such as parenteral nutrition or malabsorption, alternative repletion strategies like rectal administration of diluted sodium phosphate enemas have been used successfully to correct life-threatening hypophosphatemia (PMID 24743045). Adequate phosphorus intake is also crucial in vulnerable populations such as preterm infants, who require supplementation of human milk to meet growth and skeletal mineralization needs (PMID 28238222).

Potassium is an essential mineral that plays a critical role in maintaining electrolyte balance, nerve conduction, muscle function, and cardiovascular health. Higher dietary potassium intake is inversely associated with blood pressure and cardiovascular events, likely due to its ability to counteract the hypertensive effects of sodium (PMID 29543505). Potassium supplementation has been shown to modestly increase serum potassium levels, particularly in individuals with chronic kidney disease (CKD), though the rise is variable and influenced by concomitant medications and renal function (PMID 38070196, PMID 35609996). While potassium may exert beneficial effects on blood pressure, it also stimulates plasma aldosterone secretion, which could modulate its long-term cardiovascular benefits (PMID 38780173). However, excessive potassium intake—especially via supplementation—can lead to hyperkalemia, a potentially life-threatening condition characterized by cardiac arrhythmias, particularly in individuals with renal impairment or those taking medications that impair potassium excretion (PMID 10996582, PMID 30972536).

Selenium is an essential trace mineral that plays a critical role in human health through its incorporation into selenoproteins, such as glutathione peroxidases, which are key components of the body's antioxidant defense system (PMID 22760983, PMID 24485058). These selenoproteins help protect cells from oxidative stress, support immune function, and regulate inflammation, with emerging evidence highlighting selenium's potential in disease prevention, including cardiovascular disease and certain cancers. Low selenium status has been associated with increased risk of heart disease, impaired immune response, and worse outcomes in critically ill patients, particularly those with sepsis or COVID-19 (PMID 22760983, PMID 37739705, PMID 35057464). While selenium shows pleiotropic effects in preclinical models, including antitumor and antidiabetic properties (PMID 30532534), clinical trials have yielded mixed results, especially in cancer prevention (PMID 24485058). In ICU settings, selenium supplementation may improve outcomes in deficient patients, though evidence remains inconsistent (PMID 37739705, PMID 18443480).

Silicon, commonly found as silicon dioxide (SiO2), is a trace element that plays a role in bone and connective tissue health. Although not classified as an essential nutrient for humans, emerging evidence suggests it contributes to bone mineralization by enhancing collagen cross-linking and glycosaminoglycan formation, which improves bone strength and mechanical properties (PMID 33715532). Studies in ovariectomized rat models of osteoporosis show that oral silicon supplementation significantly increases bone mineral density in the femur and lumbar vertebrae, suggesting potential utility in postmenopausal bone loss prevention (PMID 33715532, 10602845, 25572052, 18438624). Additionally, silicon may protect against aluminum absorption, potentially reducing aluminum accumulation in the brain—a factor implicated in Alzheimer’s disease (PMID 21198634). The bioavailability of silicon depends on its form, with stabilized orthosilicic acid showing superior absorption over polymerized forms (PMID 25738207). Furthermore, colloidal silicon dioxide has demonstrated efficacy as an enterosorbent in acute diarrhea, likely due to its high surface area and adsorptive properties (PMID 32286322).

Sodium is an essential mineral that plays a critical role in fluid balance, nerve transmission, and muscle function. However, excessive sodium intake is strongly associated with elevated blood pressure, a major risk factor for cardiovascular disease. Clinical evidence shows that reducing sodium intake lowers blood pressure, particularly in individuals with hypertension. Conversely, in specific populations such as premature infants, sodium supplementation may be beneficial; early sodium supplementation in preterm infants reduced the incidence of hyponatremia and improved weight gain without increasing common morbidities (PMID 26126003). In adults, high sodium intake counteracts the blood pressure-lowering effects of potassium, and interventions that modify the sodium-potassium balance significantly impact cardiovascular risk markers (PMID 25673113). Thus, while sodium is necessary for physiological function, optimal health outcomes are associated with balanced, context-specific intake.

Zinc is an essential trace mineral involved in numerous physiological processes, including immune function, DNA synthesis, cell division, and growth. Evidence supports zinc supplementation in specific clinical contexts, particularly in populations at risk of deficiency. In children with severe pneumonia, zinc supplementation at 2 mg/kg/day (up to 20 mg/day) significantly reduced symptom duration and improved clinical outcomes when used as an adjuvant to antibiotics (PMID 21660402, 22392179). However, in radiologically confirmed pneumonia, zinc did not significantly reduce recovery time or treatment failure (PMID 28575379). Zinc supplementation has also been shown to be safe and potentially cost-effective in severe cholera (PMID 18184630) and may benefit HIV-positive adults in low-income settings by addressing common micronutrient deficiencies (PMID 27814737, 28518221). In children under 5 in low- and middle-income countries, zinc supplementation did not consistently improve growth or nutritional status (PMID 30898990). Plasma zinc levels respond rapidly to supplementation, increasing within days of initiation and declining after discontinuation, indicating its dynamic regulation (PMID 20943956).