What Nutrients Your Medication Lowers — and What to Take
Never stop a prescribed medicine because it lowers a nutrient. These medicines treat serious problems — the fix is a supplement and a check-up, not stopping the medicine. This is general information, not medical advice; talk to your doctor before making changes. As an Amazon Associate we earn from qualifying purchases; we pick products by tested cost per day, never by commission.
Some common medicines slowly lower certain vitamins and minerals in your body. The good news: for each one, there's a specific supplement that puts it back — usually for a few cents a day. This page shows you, for four common medicines, what each one lowers, how much, how strong the proof is, and exactly what to take.
What each medicine lowers — and how to fix it
This table shows, for each medicine: the nutrient it lowers, how much, how strong the evidence is, and the cheapest independently tested supplement that fixes it. Prices update on their own, so the cost is always current.
| Medicine | Lowers | How much | Evidence | What to take | Cost/day |
|---|---|---|---|---|---|
| Metformin Glucophage, Fortamet, Glumetza | Vitamin B12 | Lowers B12 about 19% over ~4 years. Roughly 1 in 9 long-term users ends up low. | Strong | A regular oral B12 tablet (cyanocobalamin is the best-tested; methylcobalamin is fine too) 1,000-2,000 mcg a day | $0.11 → |
| Statins Lipitor, Crestor, Zocor, atorvastatin, rosuvastatin, simvastatin | Coenzyme Q10 | Measurably lowers CoQ10 in your blood. | Moderate | CoQ10 (either ubiquinone or ubiquinol) 100-200 mg a day | $0.34 → |
| PPIs Prilosec, Nexium, Prevacid, omeprazole, esomeprazole, pantoprazole | Magnesium | Long-term use can lower magnesium (the FDA warned about this in 2011). | Moderate | Magnesium glycinate (gentle, absorbs well) 200-400 mg a day | $0.18 → |
| Vitamin B12 | Long-term use is linked to low B12. | Moderate | Any oral B12 (a supplement does not need stomach acid) 500-1,000 mcg a day | $0.11 → | |
| Calcium | Blocks calcium carbonate (the common cheap form). Calcium citrate still absorbs fine. | Moderate | Calcium CITRATE (switching the form is the key move) As needed alongside your diet | $0.17 → | |
| Iron | Long-term use is linked to low iron. | Moderate | Iron bisglycinate (gentler on the stomach than iron sulfate) Only if a blood test confirms you are low | $0.10 → | |
| Vitamin C | Lowers how much vitamin C you absorb from food. | Moderate | Plain vitamin C (a supplement easily makes up the difference) 250-500 mg a day if your diet is low | $0.07 → | |
| Birth control (estrogen) Combined pill / "the pill" | Folate, B6 & B12 | Linked to slightly lower folate, B6, and B12 (weaker evidence). | Limited | Methylfolate plus B12 — a methylated B-complex is the easy option A basic daily dose; 400-800 mcg methylfolate | $0.11 → |
| Magnesium | May slightly affect magnesium (weak evidence). | Limited | Magnesium glycinate 200-300 mg a day | $0.18 → |
Want the raw data? Download it as a free file: depletion-matrix.json (free to reuse with credit). Every study we used is listed at the bottom of this page.
| Item | Value |
|---|---|
| Metformin | $0.11/day |
| Statins | $0.34/day |
| PPIs | $0.18/day |
| Birth control | $0.11/day |
Why this matters: one gap can lead to a second prescription
Sometimes a missing nutrient causes a new symptom — and that symptom gets treated with a second medicine. Here's one example of how that can happen:
- You start a PPI for heartburn.
- Over 6 to 12 months, it lowers your magnesium.
- Low magnesium can cause anxiety and poor sleep.
- Those get treated with a second prescription — when the real cause was a mineral the first medicine lowered.
You can avoid this by knowing what your medicine lowers and covering it on purpose.
Metformin: what it lowers
Glucophage, Fortamet, Glumetza · Diabetes medicine · About 86 million US prescriptions a year
Metformin is the most common diabetes pill. Over years of use, it slowly lowers your vitamin B12. Most people stay fine, but about 1 in 9 long-term users ends up low — and it can cause tingling or numbness that looks just like diabetic nerve damage.
Don't stop the medicine. Do not stop metformin because of B12. It is a first-line diabetes medicine that helps you live longer. The fix is a cheap B12 supplement and an occasional blood test — not stopping the drug.
Vitamin B12: Lowers B12 about 19% over ~4 years. Roughly 1 in 9 long-term users ends up low.
What to take: A regular oral B12 tablet (cyanocobalamin is the best-tested; methylcobalamin is fine too), 1,000-2,000 mcg a day — from $0.11/day →.
How to check: Ask for a blood B12 test. If it comes back "low-normal" but you have symptoms, ask to add an MMA or "active B12" test — these catch a shortage that a normal B12 reading can miss (PMID 32089757).
Why it happens: Metformin blocks the spot at the end of your small intestine where B12 is normally absorbed. That step needs calcium, and metformin gets in the way.
The evidence: In a placebo-controlled trial, metformin lowered blood B12 by 19% over 4.3 years (de Jager, PMID 20488910). A meta-analysis found about 10.7% of users become deficient (Niafar, PMID 25502588). In the DPPOS trial, 4.3% were low at 5 years vs 2.3% on placebo, and each extra year of use added ~13% to the risk (PMID 26900641). A national survey put the odds of deficiency about 2.9x higher (PMID 22179958).
Honest note: A plain swallowed B12 tablet works fine — even though metformin blocks the gut, about 1% of a high dose still soaks in on its own (a 2,000 mcg pill matched B12 shots in a trial, PMID 9694707). Sublingual (under-the-tongue) and "methyl" B12 are sold as better, but they are not proven better than a plain tablet. The American Diabetes Association says long-term metformin users should get their B12 checked now and then, especially at higher doses or with tingling or anemia.
Statins: what it lowers
Lipitor, Crestor, Zocor, atorvastatin, rosuvastatin, simvastatin · Cholesterol medicine · About 92 million US adults
Statins are cholesterol medicines. They also lower a nutrient called CoQ10 in your blood. Whether taking CoQ10 back actually helps muscle aches is still an open question — the studies disagree — so it is worth a try, not a sure thing.
Don't stop the medicine. Do not stop a statin because of CoQ10. Statins prevent heart attacks and strokes. CoQ10 is a cheap thing to try for muscle aches, not a replacement for the drug.
Coenzyme Q10: Measurably lowers CoQ10 in your blood.
What to take: CoQ10 (either ubiquinone or ubiquinol), 100-200 mg a day — from $0.34/day →.
How to check: No blood test needed. People just try CoQ10 for a few weeks to see if muscle aches ease up.
Why it happens: Your body makes CoQ10 and cholesterol on the same assembly line. Statins shut down part of that line to lower cholesterol, and CoQ10 drops along with it.
The evidence: A meta-analysis of controlled trials found statins significantly lower CoQ10 levels in the blood (PMID 30414615).
Honest note: The drop in CoQ10 is real, but whether a supplement fixes muscle aches is mixed: one trial found no help (PMID 25545331), another found less mild-to-moderate aching (PMID 25375075), and a 2025 review weighs both (PMID 41158831). Also: statins do NOT lower vitamin D — that is a common myth (PMIDs 29067242, 36416841).
PPIs: what it lowers
Prilosec, Nexium, Prevacid, omeprazole, esomeprazole, pantoprazole · Acid-reflux medicine · About 33 million US users
PPIs are strong heartburn medicines. By cutting stomach acid, they make it harder to absorb a few nutrients when used long-term. The smartest fix here is often switching the FORM you take (for example, calcium citrate instead of calcium carbonate) — not just taking more.
Don't stop the medicine. Do not stop a PPI on your own — stopping suddenly can cause rebound heartburn, and untreated reflux has its own risks. These shortfalls matter mainly after a year or more of use. Ask your doctor about supplements or slowly cutting back.
Magnesium: Long-term use can lower magnesium (the FDA warned about this in 2011).
What to take: Magnesium glycinate (gentle, absorbs well), 200-400 mg a day — from $0.18/day →.
How to check: A blood magnesium test (note: blood can look normal even when your body stores are low).
Why it happens: PPIs interfere with the channels your gut uses to pull in magnesium (PMID 26981439).
The evidence: A meta-analysis of observational studies links PPI use to higher risk of low magnesium (PMID 31689852). The risk is highest after more than a year of use and when combined with water pills (diuretics). A 2024 review calls the link real but a bit inconsistent (PMID 35652564).
Vitamin B12: Long-term use is linked to low B12.
What to take: Any oral B12 (a supplement does not need stomach acid), 500-1,000 mcg a day — from $0.11/day →.
How to check: A blood B12 test, plus an MMA test if the result is borderline.
Why it happens: Your stomach needs acid to free B12 from food. PPIs cut that acid, so less B12 gets released (PMID 25083257).
The evidence: A large study (JAMA) linked 2+ years of PPI use to a higher chance of low B12 (PMID 24327038), and a meta-analysis confirms the link (PMID 37060552).
Calcium: Blocks calcium carbonate (the common cheap form). Calcium citrate still absorbs fine.
What to take: Calcium CITRATE (switching the form is the key move), As needed alongside your diet — from $0.17/day →.
How to check: Not usually tested — the practical fix is simply switching the form.
Why it happens: Calcium carbonate needs stomach acid to dissolve. Calcium citrate does not, so it still absorbs on a PPI.
The evidence: A randomized study showed PPIs cut absorption of calcium carbonate, which needs acid to dissolve (PMID 15989913); low stomach acid does the same (PMID 4000241). PPI use is also tied to a higher fracture risk (PMID 21483462).
Honest note: The key point: fix this by switching the FORM to calcium citrate, not by taking more calcium carbonate.
Iron: Long-term use is linked to low iron.
What to take: Iron bisglycinate (gentler on the stomach than iron sulfate), Only if a blood test confirms you are low — from $0.10/day →.
How to check: Get a ferritin and transferrin-saturation test first — do not take iron without a confirmed shortage.
Why it happens: Acid helps your gut absorb iron, and PPIs also raise a hormone (hepcidin) that blocks iron. Both push iron down (PMID 31669099).
The evidence: A large study links PPI use to iron deficiency (PMID 30141278), and a meta-analysis backs it up (PMID 35255801).
Honest note: Only take iron if a test confirms you are low. Too much iron is harmful.
Vitamin C: Lowers how much vitamin C you absorb from food.
What to take: Plain vitamin C (a supplement easily makes up the difference), 250-500 mg a day if your diet is low — from $0.07/day →.
How to check: Not usually tested; eating fruits and vegetables normally covers it.
Why it happens: With less stomach acid, vitamin C changes into a form that is harder to absorb.
The evidence: PPIs reduce how much vitamin C your body takes in and lower the amount in your stomach fluid (PMIDs 16167970, 19262546).
Birth control (estrogen): what it lowers
Combined pill / "the pill" · Estrogen birth-control pill · About 14 million US women
The estrogen birth-control pill is tied to slightly lower levels of a few B vitamins and minerals. This is the weakest evidence of the four here — mostly from observational studies — and not everyone is affected.
Don't stop the medicine. Do not stop your birth control over this — the effect is small and unproven. If you want insurance, a methylated B-complex covers the nutrients most often mentioned.
Folate, B6 & B12: Linked to slightly lower folate, B6, and B12 (weaker evidence).
What to take: Methylfolate plus B12 — a methylated B-complex is the easy option, A basic daily dose; 400-800 mcg methylfolate — from $0.11/day →.
How to check: Not usually needed — most relevant if you might become pregnant (folate) or have symptoms.
Why it happens: Estrogen shifts how the body handles B vitamins. The effect is small and varies from study to study.
The evidence: Pill users show higher homocysteine and lower folate, B6, and B12 in observational data (PMID 15013271), and reviews describe changed nutrient needs on the estrogen pill (PMID 23852908).
Honest note: Folate matters most if pregnancy is possible. B6 and zinc are also mentioned, but the evidence is thinner and we do not list a tested product for them.
Magnesium: May slightly affect magnesium (weak evidence).
What to take: Magnesium glycinate, 200-300 mg a day — from $0.18/day →.
How to check: Not usually tested.
Why it happens: Estrogen can shift where magnesium goes in the body; direct proof of a real shortfall is weak.
The evidence: Older research describes a link between magnesium and estrogen (PMID 8409107); how much this matters for today's low-dose pills is unclear.
Timing interactions: when the fix is separation, not repletion
Not every drug-nutrient issue is depletion. Some medicines are fine to take alongside supplements — as long as you space them apart. The most common example is a thyroid pill.
Levothyroxine (Synthroid, generic thyroid medicine)
Calcium, iron, and magnesium bind levothyroxine in the gut and block absorption — quietly weakening your dose if taken together. You do not have to give them up; take your thyroid pill in the morning and your minerals at lunch or dinner, at least 4 hours apart. Separately, high-dose biotin can throw off thyroid blood tests — stop it 2-3 days before labs.
Antibiotics (doxycycline, ciprofloxacin, and similar)
Tetracycline and fluoroquinolone antibiotics bind calcium, iron, magnesium, and zinc — take them at least 2 hours before or 4-6 hours after any mineral supplement, antacid, or dairy. Most other antibiotics (penicillins, amoxicillin, azithromycin) are not affected. We also cover the honest evidence on taking probiotics during a course.
More medication guides
Diuretics (water pills — HCTZ, furosemide, spironolactone)
Most diuretics lower magnesium, and some lower potassium while others raise it — so potassium is doctor-managed, not a supplement to add on your own. Read the diuretics guide →
Corticosteroids (prednisone and similar)
Long-term steroids cause bone loss; guidelines recommend calcium and vitamin D to protect your bones. Read the corticosteroids guide →
Warfarin (Coumadin blood thinner)
Keep vitamin K intake steady, and clear fish oil, ginkgo, and vitamin E with your clinic — several supplements change bleeding risk. Read the warfarin guide →
SSRIs (Zoloft, Lexapro, Prozac and other antidepressants)
The safety part matters most: never combine an SSRI with St John's Wort, 5-HTP, or SAMe (serotonin syndrome risk). Separately, methylfolate and omega-3 have real evidence as doctor-directed add-ons. Read the SSRI guide →
H2 blockers & antacids (Pepcid, Tums)
The milder cousin of PPIs — long-term use lowers vitamin B12 and iron absorption. A B12 supplement and occasional testing cover it. Read the H2/antacid guide →
ADHD stimulants (Adderall, Vyvanse, Ritalin)
The honest version: take large vitamin C doses away from your dose, and minerals only help if you're actually deficient — they don't replace medication. Read the stimulants guide →
Frequently asked questions
Which medicines lower your vitamins and minerals?
The four with the best evidence are: metformin (lowers vitamin B12 about 19% over ~4 years; about 1 in 9 long-term users ends up low), statins (measurably lower CoQ10), PPI heartburn medicines (make it harder to absorb magnesium, B12, calcium, iron, and vitamin C over the long term), and the estrogen birth-control pill (linked to slightly lower folate, B6, and B12). The metformin, statin, and PPI evidence is the strongest; the birth-control link is the weakest of the four.
Should I stop my medicine because it lowers a nutrient?
No. Never stop a prescribed medicine because it lowers a nutrient. Statins prevent heart attacks, metformin helps people with diabetes live longer, and heartburn medicines treat problems that carry their own risks. The fix is a cheap supplement — often just a few cents a day — and, when it matters, an occasional blood test. Talk to your doctor before making any changes.
How much does it cost to fix?
Very little — usually about 35 cents a day or less. A B12 tablet for metformin runs about $0.11 a day, CoQ10 for a statin about $0.34 a day, and magnesium glycinate for a PPI about $0.18 a day. Often the smartest move is picking the right form — for example, using calcium citrate on a PPI (it doesn't need stomach acid) instead of taking more calcium carbonate.
Related
- Depletion analyzer — enter your medicines and get a personalized list of what to check
- Stack builder — build a supplement plan around your medicines, goals, and health
- Always tired? — tiredness is the most common sign of a medicine lowering a nutrient
- Tingling hands & feet — a warning sign of low B12 that looks like diabetic nerve pain
- Which B12 to buy — methylcobalamin vs cyanocobalamin, and why "active" isn't automatically better
Sources
- PMID 20488910
- PMID 25502588
- PMID 26900641
- PMID 22179958
- PMID 10977010
- PMID 9694707
- PMID 29543316
- PMID 32089757
- PMID 30414615
- PMID 17560286
- PMID 25545331
- PMID 25375075
- PMID 41158831
- PMID 29067242
- PMID 36416841
- PMID 31689852
- PMID 26981439
- PMID 35652564
- PMID 24327038
- PMID 37060552
- PMID 25083257
- PMID 15989913
- PMID 4000241
- PMID 21483462
- PMID 30141278
- PMID 35255801
- PMID 31669099
- PMID 16167970
- PMID 19262546
- PMID 15013271
- PMID 23852908
- PMID 8409107
We checked every study above against the US National Library of Medicine database (PubMed) on 2026-07-14 — confirming each one is real, is about the claim we used it for, and has not been retracted.