Abstract
Background: The long-term use of prescription medications is an established but systematically underappreciated cause of micronutrient deficiencies. Drug-induced nutrient depletion (DIND) arises from mechanistically distinct interactions — enzymatic pathway inhibition, transporter antagonism, acid-suppression-mediated solubility changes, and accelerated urinary excretion — which together constitute a form of iatrogenic malnutrition with significant clinical consequences. Medical education has historically prioritised drug–drug interactions, leaving drug–nutrient interactions comparatively neglected in prescribing practice.
Objective: This review examines the molecular and physiological mechanisms underlying DIND for three of the most widely prescribed drug classes: HMG-CoA reductase inhibitors (statins), biguanides (metformin), and proton pump inhibitors (PPIs). Emphasis is placed on mechanistic precision, clinical sequelae, and evidence-based recommendations for monitoring and intervention.
Conclusion: DIND is a clinically relevant, mechanistically explicable, and largely preventable complication of chronic pharmacotherapy. Routine surveillance for drug-specific nutrient deficiencies should be integrated into the standard of care for patients on long-term statin, metformin, or PPI therapy.
Keywords: drug-induced nutrient depletion; iatrogenic deficiency; statins; coenzyme Q10; metformin; vitamin B12; proton pump inhibitors; hypomagnesemia; mevalonate pathway; cubilin receptor
1. Introduction
The global burden of chronic non-communicable diseases has driven an unprecedented expansion of polypharmacy. In developed nations, a majority of adults over 55 years take at least one prescription medication daily, and a substantial proportion take five or more. [^1] This pharmacological landscape has created a population chronically exposed to drug–nutrient interactions — a category of adverse effect that develops insidiously over months to years and whose clinical manifestations are frequently misattributed to disease progression, ageing, or new pathology. [^2]
The conceptual framework of DIND distinguishes three broad mechanistic categories: (1) drugs that impair nutrient absorption, either by altering luminal chemistry or competing with specific membrane transporters; (2) drugs that inhibit biosynthetic or metabolic pathways on which endogenous nutrient synthesis depends; and (3) drugs that accelerate nutrient excretion or catabolism. [^3][^4] All three mechanisms are represented among commonly prescribed medications, yet surveys consistently demonstrate that prescribing physicians receive little formal training in drug–nutrient interactions, creating a knowledge gap with tangible patient harm. [^5]
This article presents a mechanistically focused review of DIND as exemplified by three drug classes of particular clinical importance: statins (blocking endogenous coenzyme Q10 synthesis via the mevalonate pathway), metformin (antagonising calcium-dependent ileal absorption of vitamin B12), and PPIs (impairing intestinal absorption of magnesium and iron through achlorhydria and transporter dysregulation). These three examples were selected because their mechanisms are molecularly well-characterised, their clinical consequences are serious and underdiagnosed, and their prevalence in chronic prescribing practice makes them of immediate relevance to any practising internist.
2. Molecular Classification of Drug–Nutrient Interactions
Before examining individual drug classes, it is useful to establish a mechanistic taxonomy. Boullata and Hudson (2012) proposed a framework categorising drug–nutrient interactions by the biological locus of interference: intestinal transport and metabolism, systemic distribution, hepatic and renal metabolism, and excretion. [^6] Drugs can reduce nutrient bioavailability through decreased oral intake (anorexia, dysgeusia), altered absorption kinetics, competitive inhibition of intestinal transporters, displacement from plasma binding proteins, induction of hepatic metabolising enzymes, or enhancement of urinary elimination. [^7]
A critical conceptual distinction must be made between drug–nutrient interactions (pharmacokinetic or pharmacodynamic effects on administered nutrients) and drug-induced nutrient depletion (reduction in endogenous nutrient status as a consequence of pharmacological mechanisms). The latter is arguably more clinically insidious because it does not require co-administration of the nutrient to manifest: the deficiency arises from the pharmacological mechanism itself, independent of dietary intake. It is in this category that statins, metformin, and PPIs are paradigmatic examples.
The clinical relevance of any DIND depends on multiple factors: the baseline nutritional status of the patient, the dose and duration of therapy, concomitant medications with overlapping depletion profiles, individual genetic variation in transporter or enzyme expression, and the physiological reserve of the nutrient in question. [^3] Elderly and chronically ill patients face a convergence of these risk factors: they take more medications, have reduced dietary intake and absorption capacity, and have diminished physiological reserves — making DIND in these populations both more likely and more consequential. [^8]
3. Statins and Coenzyme Q10 Depletion: Inhibition of the Mevalonate Pathway
3.1 Biochemistry of the Mevalonate Pathway
HMG-CoA reductase inhibitors exert their primary therapeutic effect by competitively inhibiting 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme catalysing the conversion of HMG-CoA to mevalonate. This reaction is the committed first step in the mevalonate pathway, a biosynthetic cascade responsible not only for cholesterol synthesis but also for the production of a series of biologically essential isoprenoid intermediates, including farnesyl pyrophosphate, geranylgeranyl pyrophosphate, dolichol, and critically, the isoprenoid side-chain of coenzyme Q10 (ubiquinone). [^9][^10]
Coenzyme Q10 (CoQ10, ubiquinone) is a lipophilic quinone synthesised in the inner mitochondrial membrane. Its primary function is as a mobile electron carrier within the mitochondrial respiratory chain, shuttling electrons between complex I (NADH:ubiquinone oxidoreductase) and complex III (ubiquinol:cytochrome c oxidoreductase), a role that is indispensable for oxidative phosphorylation and ATP generation. Beyond bioenergetics, CoQ10 functions as a potent lipophilic antioxidant and membrane stabiliser, capable of regenerating other antioxidants including tocopherols and ascorbate. [^11] Cardiovascular and skeletal muscle tissue are particularly dependent on adequate CoQ10 due to their exceptionally high metabolic demands.
3.2 Mechanism of Statin-Induced CoQ10 Depletion
Because the isoprenoid side-chain of CoQ10 is synthesised downstream of mevalonate via farnesyl pyrophosphate, any inhibition of HMG-CoA reductase necessarily restricts the substrate available for CoQ10 biosynthesis. Statin therapy has been consistently demonstrated to lower plasma and serum CoQ10 concentrations. [^12][^13] However, a nuanced distinction must be drawn between plasma CoQ10 levels — which are substantially influenced by the reduction in LDL cholesterol (the primary plasma carrier of CoQ10) that statins achieve — and actual tissue CoQ10 status, which reflects intracellular bioenergetic sufficiency.
Littarru and Langsjoen (2007) reviewed the biochemical evidence and noted that while plasma CoQ10 clearly falls during statin therapy, reductions have also been documented in platelets and lymphocytes, consistent with a genuine biosynthetic suppression rather than merely a redistribution effect secondary to LDL lowering. [^12] Hargreaves et al. (2005), reviewing human tissue data from studies that directly measured muscle CoQ10 content in statin-treated patients, found the evidence less conclusive, noting that most studies used sub-maximal statin doses and that tissue distribution to liver and muscle — the principal target organs of statin toxicity — may not be adequately captured by peripheral tissue sampling. [^14]
The clinical consequence most directly attributed to CoQ10 depletion is statin-associated myopathy (SAM), a spectrum ranging from asymptomatic creatine kinase elevation to debilitating myalgia and, at its most severe, rhabdomyolysis. Mas and Mori (2010) reviewed the inter-relationship between statin therapy and CoQ10 concentrations in plasma and tissues, concluding that CoQ10 deficiency is a plausible contributing mechanism to SAM through mitochondrial dysfunction and impaired bioenergetics in skeletal muscle cells, though this does not exclude parallel mechanisms such as mevalonate-dependent effects on isoprenylation of small GTPases. [^15]
Beyond myopathy, a body of evidence suggests that subclinical CoQ10 depletion may compromise myocardial bioenergetics. Silver et al. (2003) described a protocol examining diastolic left ventricular function — a highly ATP-dependent process — as an early marker of statin-induced myocardial dysfunction, hypothesising that CoQ10 restoration could reverse these subclinical changes. [^2] The broader implication is that a drug class prescribed for cardiovascular protection may, through CoQ10 depletion, simultaneously impose a low-grade bioenergetic burden on the very organ system it aims to protect — a pharmacological paradox with important clinical resonance.
3.3 The Case of Vitamin K2: An Underappreciated Secondary Depletion
Beyond CoQ10, the mevalonate pathway is also required for the geranylgeranyl pyrophosphate moieties involved in the prenylation of vitamin K2 (menaquinone) side chains. Statins have been proposed to reduce endogenous menaquinone bioavailability by restricting the isoprenoid precursors necessary for its synthesis; however, the clinical data on this specific interaction remain less robust than those for CoQ10. Mohn et al. (2018) noted in their comprehensive update of drug–nutrient interactions that statin-related effects on vitamin K2 status warrant further investigation given the vitamin's critical roles in carboxylation of matrix Gla protein (MGP) and osteocalcin — functions relevant to vascular calcification and bone metabolism. [^16]
3.4 Clinical Implications and Monitoring
Given that CoQ10 depletion is a mechanistically necessary consequence of HMG-CoA reductase inhibition, and given the high global prevalence of statin use (tens of millions of patients on chronic therapy), the clinical relevance is substantial. The Mohammadi-Bardbori and Hosseini (2015) review summarised clinical evidence that CoQ10 supplementation during statin therapy may reduce myopathic symptoms in susceptible patients. [^17] A randomised controlled trial by Mazirka et al. confirmed that CoQ10 supplementation attenuates statin-related myalgia in affected patients. [^18] While widespread routine supplementation is not yet supported by guidelines, Grober, Schmidt, and Kisters (2018), in a widely cited review in Critical Reviews in Food Science and Nutrition, recommend monitoring of CoQ10 status in patients on high-dose statin therapy or those experiencing unexplained fatigue and myalgia. [^19]
4. Metformin and Vitamin B12 Deficiency: Calcium-Dependent Ileal Absorption Antagonism
4.1 Normal Physiology of Vitamin B12 Absorption
Vitamin B12 (cobalamin) absorption is a multi-step process with several points of potential failure. Dietary cobalamin, released from food proteins by gastric pepsin, binds to haptocorrin (R-protein) in the stomach. In the duodenum, pancreatic proteases hydrolyse this complex, and free cobalamin binds to intrinsic factor (IF), a glycoprotein secreted by gastric parietal cells. The resulting IF-cobalamin complex transits to the terminal ileum, where it binds with high affinity to cubilin (CUBN), a multiligand endocytic receptor expressed on ileal enterocytes. This binding step is explicitly calcium-dependent: the cubilin receptor requires divalent calcium ions for conformational activation and for stable engagement with the IF-cobalamin complex. [^20][^21] Following receptor binding, the complex is internalised via megalin-mediated endocytosis, and cobalamin is subsequently released and transported to the portal circulation bound to transcobalamin II (TCII, holotranscobalamin).
4.2 Mechanism of Metformin-Induced B12 Malabsorption
Metformin's interference with this process centres on its action at the ileal brush border membrane. Bauman et al. (2000) published a landmark study in Diabetes Care demonstrating that oral calcium supplementation reversed the reduction in both total serum vitamin B12 and holotranscobalamin (holoTCII, the biologically active fraction) in metformin-treated patients — providing direct clinical evidence that metformin antagonises calcium-dependent ileal membrane function. [^20] This remains the most cited mechanistic evidence for metformin's B12-depleting effect.
Muralidharan et al. (2024), using a novel stable isotope tracer ($$[^{13}C]$$-cyanocobalamin) in a crossover pilot study, demonstrated that metformin administration reduced B12 bioavailability from approximately 42.6% at baseline to 30.8%, and that co-administration of 500 mg calcium restored bioavailability to 46.4% — a statistically significant reversal. [^22] This isotope-labelling methodology provides the strongest direct mechanistic evidence to date, confirming that metformin's inhibition of the calcium-dependent IF-B12/cubilin interaction is the primary mechanism, not merely an epiphenomenon.
Additional mechanisms have been proposed to contribute: altered small intestinal motility, changes in bile acid metabolism affecting cobalamin enterohepatic recycling, and gut microbiome dysbiosis with bacterial sequestration of cobalamin. Panou and Asimakopoulos (2025), in a recent comprehensive mechanistic review, concluded that while calcium-dependent cubilin antagonism remains the most evidenced mechanism, these secondary mechanisms may explain the cases where calcium supplementation provides incomplete restoration of B12 status. [^23]
4.3 Prevalence and Dose-Dependency
The prevalence of metformin-associated B12 deficiency is estimated at 6–30% of long-term users, with higher rates at greater doses and longer duration of therapy. Al Zoubi et al. (2024), in a narrative review in the Irish Journal of Medical Science, reported that daily dose appears more strongly associated with deficiency risk than duration alone, and that doses exceeding 2,000 mg/day over four or more years carry the highest risk. [^24] Male sex and concomitant PPI use (which independently impairs B12 absorption by reducing parietal cell IF secretion and gastric acid necessary for food-bound cobalamin release) are established aggravating factors. [^24]
4.4 Clinical Sequelae
The clinical consequences of cobalamin deficiency extend well beyond megaloblastic anaemia. Bell (2022), in a comprehensive review in Diabetes, Obesity and Metabolism, documented that metformin-induced B12 deficiency can initiate or accelerate distal symmetrical polyneuropathy, autonomic neuropathy, and cardiac autonomic neuropathy — the latter associated with increased arrhythmia risk and cardiovascular mortality. [^25] Crucially, the peripheral neuropathy of B12 deficiency is clinically indistinguishable from diabetic neuropathy, creating a diagnostic trap: the most common reason physicians may overlook DIND is that the drug-induced deficiency symptom mimics the underlying disease itself.
Hyperhomocysteinaemia is a secondary biochemical consequence of B12 deficiency, resulting from impaired methionine synthase activity and accumulation of homocysteine. Given that elevated homocysteine is an independent risk factor for atherothrombotic disease, metformin-induced B12 depletion carries cardiovascular implications beyond neuropathy — a further pharmacological irony in a drug prescribed in the context of a condition (type 2 diabetes) already associated with elevated cardiovascular risk.
4.5 Monitoring and Management
The American Diabetes Association standards of care recommend periodic assessment of vitamin B12 status in all patients on chronic metformin therapy. Bell (2022) advises annual monitoring with serum B12, and where borderline results are obtained, confirmatory measurement of methylmalonic acid (MMA) and homocysteine, which are more sensitive early markers of functional B12 deficiency than serum cobalamin alone. [^25] Sireesha et al. (2024) recommend monitoring at least annually, with consideration of prophylactic calcium and/or B12 supplementation in high-risk patients. [^26]
5. Proton Pump Inhibitors and the Depletion of Magnesium and Iron
5.1 Mechanisms of PPI-Induced Hypomagnesaemia
Proton pump inhibitors suppress gastric acid secretion by irreversibly binding to and inactivating the H⁺/K⁺-ATPase proton pump in parietal cells, resulting in sustained hypochlorhydria or achlorhydria. While this mechanism effectively controls acid-related pathology, it has far-reaching consequences for mineral absorption.
Magnesium homeostasis in humans depends on two intestinal absorption mechanisms: a saturable transcellular pathway in the small intestine, mediated principally by the transient receptor potential melastatin channels TRPM6 and TRPM7, and a paracellular pathway operating along the length of the intestine. Gommers, Hoenderop, and de Baaij (2022), in a detailed mechanistic review in Acta Physiologica, proposed that PPI-induced hypomagnesaemia results from multiple converging mechanisms: (1) reduced Mg²⁺ solubility in the intestinal lumen as luminal pH rises, since Mg²⁺ solubility is inversely related to pH; (2) pH-dependent downregulation of TRPM6/TRPM7 expression and activity in both small intestinal and colonic enterocytes; and (3) PPI-induced alterations in gut microbiome composition, which reduce microbial fermentation of dietary fibres and thereby diminish the luminal acidification that normally supports paracellular Mg²⁺ absorption in the colon. [^27]
The systematic review by Hess et al. (2012) in Alimentary Pharmacology & Therapeutics confirmed the association between long-term PPI use and hypomagnesaemia across multiple observational datasets. [^28] Cundy and Dissanayake (2008), examining the mechanism in affected patients, demonstrated that urinary magnesium excretion was markedly reduced — indicating a renal compensatory response to primary intestinal malabsorption, not renal wasting, as the driver. [^27] This finding effectively excluded renal tubular dysfunction as the mechanism and localised the defect to intestinal absorption. William and Danziger (2016) further elaborated that genetic variation in TRPM6/TRPM7 may explain why only a subset of long-term PPI users develop clinically significant hypomagnesaemia. [^29]
Hypomagnesaemia is not a benign biochemical finding. Severe cases — defined as serum Mg²⁺ below 0.4 mmol/L — can precipitate refractory hypokalaemia, hypocalcaemia (through impaired parathyroid hormone secretion), ventricular arrhythmias, and generalised seizures. Famularo, Gasbarrone, and Minisola (2013) reported that PPI-induced hypomagnesaemia was refractory to magnesium replacement therapy until PPIs were discontinued — a clinical observation with significant implications for management. [^30]
5.2 Mechanisms of PPI-Induced Iron Deficiency
Dietary non-haem iron absorption is governed by a reductive dissolution mechanism: ferric iron (Fe³⁺), the predominant form in plant-based foods and iron salts, is poorly absorbed unless reduced to the soluble ferrous form (Fe²⁺). This reduction is facilitated by gastric acid, which maintains the low pH of the proximal duodenal lumen necessary for the activity of duodenal cytochrome b (DCYTB), the ferric reductase expressed on the intestinal brush border. PPI-induced achlorhydria directly impairs this ionisation and reduction step, increasing luminal pH and reducing the solubility and subsequent absorptive efficiency of non-haem iron. [^31]
Beyond this physicochemical mechanism, a molecularly distinct pathway has been identified by Hamano et al. (2019). In HepG2 cell lines and mouse models, the PPI omeprazole upregulated hepatic hepcidin expression via the aryl hydrocarbon receptor (AhR)-mediated pathway, leading to reduced duodenal ferroportin protein levels and impaired iron export from enterocytes into the portal circulation. [^32] This represents a direct pharmacological effect on iron regulatory hormones independent of acid suppression, adding a second, mechanistically separate pathway through which PPIs impair iron homeostasis.
Sheen and Triadafilopoulos (2011), in a comprehensive review of long-term PPI adverse effects, noted that iron deficiency anaemia from PPI-associated malabsorption is most clinically significant in populations with high physiological iron demand or pre-existing borderline status: pre-menopausal women, patients with chronic blood loss, and those already on oral iron supplementation. [^33] Dado, Loesch, and Jaganathan (2017) documented a case of severe iron deficiency anaemia attributable to long-term PPI use in a patient in whom iron absorption studies confirmed gastrointestinal malabsorption reversible upon PPI discontinuation. [^34]
5.3 Additional PPI-Associated Depletions
The achlorhydric gastric environment created by PPIs does not selectively impair only magnesium and iron. Reduced gastric acid also compromises the proteolytic release of protein-bound vitamin B12 from food, impairs calcium ionisation and absorption (with implications for bone mineral density), and reduces zinc absorption. [^4] The co-prescription of metformin and a PPI — a common combination in patients with type 2 diabetes and acid reflux — creates a pharmacologically compounded depletion of vitamin B12, since both drugs impair its absorption through distinct mechanisms (metformin via calcium-dependent cubilin antagonism; PPIs by reducing both intrinsic factor secretion and the acid-dependent release of food-bound cobalamin). Bell (2022) specifically identified PPI use as an accelerating factor for hepatic B12 store depletion in metformin-treated patients. [^25]
6. Discussion
6.1 The Diagnostic Gap
A unifying feature of DIND across all three drug classes reviewed is the temporal mismatch between pharmacological exposure and clinical manifestation. CoQ10 depletion during statin therapy, B12 depletion during metformin therapy, and magnesium depletion during PPI therapy all develop gradually over months to years, and clinical symptoms typically emerge only when tissue reserves are substantially depleted. The insidious onset creates a diagnostic trap: by the time symptoms appear, the biochemical deficiency is often severe, and the causal connection to the prescribed medication is not intuitive to the prescriber.
This diagnostic gap is compounded by symptomatic mimicry: statin-associated myopathy may be attributed to deconditioning; metformin-induced neuropathy may be diagnosed as diabetic neuropathy; PPI-induced fatigue and cardiac arrhythmias may be attributed to the underlying disease or to ageing. Yalçın et al. (2020) emphasised that physicians should explicitly consider whether symptoms represent drug-induced nutritional disorders before attributing them to disease progression or initiating additional pharmacotherapy. [^35]
6.2 Polypharmacy and Additive Depletion
The problem is substantially amplified by polypharmacy. Samaras et al. (2013) noted that drug-induced micronutrient depletions may be the origin of otherwise unexplained symptoms that sometimes influence medication compliance, and emphasised that the cumulative effect of multiple medications with overlapping depletion profiles is rarely considered at the time of prescribing. [^36] Laight (2023) highlighted that vitamin and mineral depletion is an often under-recognised side-effect of pharmacotherapy and called for prescribers to consider these interactions more systematically. [^37]
The clinical scenario of an elderly patient on a statin, metformin, and a PPI — a combination that is common in the management of type 2 diabetes with dyslipidaemia and gastro-oesophageal reflux — represents a pharmacological convergence that simultaneously depletes CoQ10, vitamin B12, magnesium, calcium, iron, and zinc. No current prescribing guideline provides a systematic framework for managing this cumulative risk.
6.3 The Educational Dimension
The systematic exclusion of drug–nutrient interactions from standard medical curricula has been noted for decades. Knapp (1995) reported in the Journal of the American College of Nutrition that drug–nutrient interactions were systematically absent from medical training programmes. [^38] The persistence of this gap — documented across multiple subsequent surveys — suggests that the problem is structural rather than incidental. Medical students and resident physicians are trained to think in terms of pharmacokinetic drug–drug interactions (induction or inhibition of cytochrome P450 isoenzymes, P-glycoprotein competition) while the mechanistically analogous phenomena of drug–nutrient pathway interference remain largely invisible to clinical training.
6.4 Limitations of Current Evidence
Several important limitations qualify the evidence reviewed. For CoQ10 and statins, the mechanistic link between plasma CoQ10 depletion and tissue-level bioenergetic deficiency remains incompletely established in human studies, partly because of challenges in measuring intracellular CoQ10 in relevant tissues (myocardium, skeletal muscle) non-invasively. For metformin and B12, most prevalence data come from observational studies at risk of confounding by dietary intake and baseline nutritional status. For PPIs and magnesium, while the association is well-established, the precise contribution of each proposed mechanism (solubility, transporter downregulation, microbiome) to total impairment of absorption has not been quantified in controlled human studies. Mohn et al. (2018) noted that for the majority of drug–nutrient interactions, more high-quality interventional trials are needed. [^16]
7. Management Principles and Clinical Recommendations
Although universal supplementation is not warranted across unselected populations on these drug classes, a risk-stratified approach is clinically prudent.
For patients on statin therapy: monitor for myopathic symptoms and unexplained fatigue. In patients on high-dose statins (particularly atorvastatin 40–80 mg or rosuvastatin 20–40 mg) or those with pre-existing mitochondrial disease, cardiomyopathy, or statin-associated myalgia, measurement of CoQ10 status and consideration of supplementation (100–300 mg/day of reduced ubiquinol) is reasonable. Grober et al. (2018) and Mohn et al. (2018) support this risk-stratified approach. [^16][^19]
For patients on metformin therapy: annual measurement of serum vitamin B12 (with holotranscobalamin preferred for sensitivity) is recommended by the ADA and supported by the reviewed literature. Where deficiency is confirmed, oral B12 supplementation (1,000 µg/day) or intramuscular repletion is appropriate. Prophylactic co-administration of 500–1,000 mg elemental calcium daily is supported by the mechanistic evidence for calcium-dependent reversal of cubilin receptor antagonism. Periodic measurement of MMA and homocysteine is indicated when serum B12 is borderline or when neuropathy is present. [^20][^22][^25]
For patients on long-term PPI therapy: serum magnesium should be checked before initiating long-term therapy in at-risk patients (those on digoxin, anti-arrhythmics, or diuretics), and at regular intervals thereafter. Consideration of H2-receptor antagonist substitution should be made where acid suppression requirements permit, as this class does not impair TRPM6/TRPM7-mediated magnesium absorption. In patients with iron deficiency anaemia on long-term PPIs, the PPI itself should be considered as a contributing aetiology and parenteral iron may be required if oral iron therapy is ineffective. [^27][^30][^33]
8. Conclusion
Drug-induced nutrient depletion represents a mechanistically well-characterised, clinically underdiagnosed, and preventable iatrogenic phenomenon. The three examples examined — statins depleting CoQ10 through mevalonate pathway inhibition, metformin depleting vitamin B12 through calcium-dependent cubilin receptor antagonism, and PPIs depleting magnesium and iron through achlorhydria-mediated transporter dysregulation and hepcidin upregulation — collectively illustrate that the adverse nutritional consequences of pharmacotherapy operate through mechanisms as precise and teachable as any conventional pharmacological target. The central barrier to recognition and prevention is not the complexity of the science but the structural absence of this science from medical education and prescribing frameworks. Integrating drug–nutrient interaction surveillance into standard prescribing practice, commensurate with the attention given to drug–drug interactions, represents a straightforward and high-yield opportunity to reduce iatrogenic morbidity in the growing population of patients on chronic polypharmacy.
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This review is grounded in an initial targeted literature search; a systematic database review with PRISMA methodology would capture additional primary trials and may modify specific evidence gradings.
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[^2]: Mohn et al., 2018. Evidence of Drug–Nutrient Interactions with Chronic Use of Commonly Prescribed Medications: An Update. Pharmaceutics.
[^3]: White & Ashworth, 2000. How drug therapy can affect, threaten and compromise nutritional status. Journal of Human Nutrition and Dietetics.
[^4]: Yalçın et al., 2020. Drug-induced nutritional disorders.
[^5]: Felípez & Sentongo, 2009. Drug-induced nutrient deficiencies. The Pediatric clinics of North America.
[^6]: Boullata & Hudson, 2012. Drug-nutrient interactions: a broad view with implications for practice. Journal of the Academy of Nutrition and Dietetics.
[^7]: White & Ashworth, 2000. How drug therapy can affect, threaten and compromise nutritional status. Journal of Human Nutrition and Dietetics.
[^8]: Mohn et al., 2018. Evidence of Drug–Nutrient Interactions with Chronic Use of Commonly Prescribed Medications: An Update. Pharmaceutics.
[^9]: Mabuchi et al., 2007. Coenzyme Q10 Reduction with Statins: Another Pleiotropic Effect. Current Drug Therapy.
[^10]: Mthembu et al., 2022. Impact of dyslipidemia in the development of cardiovascular complications: Delineating the potential therapeutic role of coenzyme Q10. Biochimie.
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[^12]: Maleskey, 2009. Statins , Muscle Damage , and Coenzyme Ql 0.
[^13]: Hargreaves et al., 2005. The Effect of HMG-CoA Reductase Inhibitors on Coenzyme Q10. Drug Safety.
[^14]: Mas & Mori, 2010. Coenzyme Q10 and Statin Myalgia: What is the Evidence?. Current Atherosclerosis Reports.
[^15]: Silver et al., 2003. Statin cardiomyopathy? A potential role for Co‐Enzyme Q10 therapy for statin‐induced changes in diastolic LV performance: Description of a clinical protocol. Biofactors.
[^16]: Mohammadi-Bardbori & Hosseini, 2015. Therapeutic implication of coenzyme Q10 during statin therapy: pros and cons.
[^17]: Mazirka et al., 2015. Effect of Coenzyme Q10 Supplementation in Patients with Statin‐related Myalgia. The FASEB Journal.
[^18]: Gröber et al., 2018. Important drug-micronutrient interactions: A selection for clinical practice. Critical reviews in food science and nutrition.
[^19]: Bauman et al., 2000. Increased intake of calcium reverses vitamin B12 malabsorption induced by metformin. Diabetes Care.
[^20]: Metformin And Vitamin B12 Deficiency: A Concise Exploration, 2024. Journal of Clinical and Laboratory Research.
[^21]: Muralidharan et al., 2024. Effect of calcium supplementation on reversing metformin-based inhibition of vitamin B12 bioavailability in healthy adults using a [13C] cyanocobalamin tracer - A pilot study. Clinical Nutrition ESPEN.
[^22]: Panou & Asimakopoulos, 2025. What ultimately underlies vitamin B12 and folate deficiency in subjects treated with biguanides?. HORMONES.
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