Vitamin C (Magnesium Ascorbate)

Buffered vitamin C combined with magnesium for enhanced tolerance and dual mineral benefits

Scientific nameMagnesium L-Ascorbate FormulaC12H14MgO12 Molecular weight374.54 g/mol

85 absorption score

9 safety / 10

20 USD per month

6 elemental magnesium %

5 documented interactions

Check it against something

Evidence level A

Vitamin C (Magnesium Ascorbate) with:

99 out of 100

Works better together Compatible. Timing differs, so follow each supplement's own window.

Check it against your whole stack →

What it does

mechanism and evidence for each claim

Dual nutrient supplementation

Provides both vitamin C and magnesium in one supplement

Combined antioxidant and mineral supplementation Evidence A-grade 2-4 weeks

Enhanced stomach tolerance

Non-acidic form reduces gastric irritation

Buffered pH prevents stomach acid stimulation Evidence A-grade Immediate

Muscle and nerve support

Magnesium provides muscle relaxation and nerve function

Magnesium regulates calcium channels and muscle contraction Evidence A-grade 1-3 weeks

Cardiovascular benefits

Both nutrients support heart health synergistically

Antioxidant protection plus vascular muscle relaxation Evidence A-grade 4-8 weeks

Energy metabolism support

Magnesium enhances cellular energy production

Required for ATP synthesis and enzyme function Evidence A-grade 2-4 weeks

Others take these for the same thing

Same goal, different mechanism — check any of them against this one

Creatine Monohydrate Strength & power enhancement 3-5g A 95% Calcium Bone health & muscle function 1,000-1,200 mg A 30% Magnesium Glycinate Superior absorption sleep & muscle support 200-600 mg A 90% Whey Protein Muscle growth & recovery 25-75g A 95% Creatine HCL Enhanced muscle building 1.5-3g B 98% Oregano Oil Powerful respiratory antimicrobial 100-300mg B 85%

Every pair we checked

12 combinations scored by the engine

Vitamin C (Magnesium Ascorbate) + Caffeine No documented interaction either way No known interaction 70

Vitamin C (Magnesium Ascorbate) + Creatine Monohydrate No documented interaction either way No known interaction 70

Vitamin C (Magnesium Ascorbate) + Whey Protein No documented interaction either way No known interaction 70

Vitamin C (Magnesium Ascorbate) + Turmeric No documented interaction either way No known interaction 70

Vitamin C (Magnesium Ascorbate) + Lactase Improved calcium absorption when consuming dairy Works better together 82

Vitamin C (Magnesium Ascorbate) + Bovine Collagen Essential for collagen synthesis and cross-linking Works better together 82

Vitamin C (Magnesium Ascorbate) + DHA Prevents oxidation of DHA and enhances stability Works better together 82

Vitamin C (Magnesium Ascorbate) + Fish Oil (EPA/DHA) Protects fish oil from oxidation Works better together 90

Vitamin C (Magnesium Ascorbate) + Vitamin D3 Magnesium required for vitamin D activation Works better together 99

Vitamin C (Magnesium Ascorbate) + Calcium Carbonate High calcium can deplete magnesium Needs attention 99

Vitamin C (Magnesium Ascorbate) + Vitamin C (Ascorbic Acid) Magnesium required for vitamin D activation Works better together 99

Vitamin C (Magnesium Ascorbate) + Calcium Bone Formula High calcium can deplete magnesium Needs attention 99

Dosage

Divided doses with meals

Daily500-2000 mg

Maintenance500-1000 mg

Therapeutic1500-3000 mg

Magnesium content125mg magnesium per 1000mg vitamin C

Laxative thresholdAbove 400mg magnesium per day

Upper limit 2000 mg NIH ODS

Before you take it

VeganYes

When to expect it

First Effects24-48 hours for immune and muscle benefits

Peak Benefits4-8 weeks for combined cardiovascular and energy benefits

Deficiency DevelopmentVitamin C: 4-12 weeks, Magnesium: 2-8 weeks

Toxicity OnsetMainly laxative effects from magnesium

How to measure it

$60-120 for both tests

MarkerPlasma vitamin C + serum/RBC magnesium

OptimalVitamin C: 50-114 μmol/L, Mg: 0.75-0.95 mmol/L

Deficient belowVitamin C: <11 μmol/L, Mg: <0.75 mmol/L

FrequencyMonitor magnesium if using high doses regularly

What people actually reported to the FDA

CAERS, 245 reports naming it as the suspect

Most reported effects

Dyspnoea 50

Nausea 22

Hypersensitivity 18

Abdominal pain upper 18

Excluded from the list above: choking (41), dysphagia (19). Those are people struggling with the tablet itself, not with the compound.

Named as the suspect 245 reports of 1,000+ that mention it at all

Serious outcome 79% hospitalisation, emergency room or worse

Other Serious or Important Medical Event167

Visited a Health Care Provider57

Hospitalization53

Reports are voluntary and unverified — they record what someone experienced while taking something, not what the compound caused. Counts skew towards products people take a lot of, and a serious outcome is more likely to be reported than a mild one, so these are not rates. How we filter them →

What actually reaches you

The label counts the carrier, your body does not

Elemental magnesium 6.5% of 374.54 g/mol

Absorption Very high 85 of 100 · best absorbed form of this compound

Delivered daily 69.1 mg

Cost per 100 mg delivered $0.97 comparative — uses the absorption score, not a measured percentage

A 500 mg capsule of Vitamin C (Magnesium Ascorbate) contains 33 mg of magnesium. How much of that crosses into your blood is not measured for this form — the absorption score ranks it against other forms, it is not a share of the dose. How this is calculated →

Works better with

3 documented

Vitamin D

Magnesium required for vitamin D activation

Cofactor for vitamin D metabolizing enzymes · level A

Calcium

Magnesium balances calcium function

Maintains proper calcium:magnesium ratio · level A

Vitamin B6

B6 enhances magnesium cellular uptake

Improves magnesium transport into cells · level B

What not to take with Vitamin C (Magnesium Ascorbate)

2 documented

Calcium Excess

High calcium can deplete magnesium

Competition for absorption and cellular uptake · moderate significance

Alcohol

Depletes both vitamin C and magnesium

Increased excretion and impaired absorption · moderate significance

Medication interactions

Discuss these with a pharmacist before combining

antibiotics-tetracycline Major

Magnesium reduces antibiotic absorption

What to do: Space doses 2-4 hours apart

diuretics Moderate

Some diuretics increase magnesium loss

What to do: Monitor magnesium status

ppi-acid-blockers Minor

May reduce magnesium absorption

What to do: Monitor for deficiency signs

Available forms

bioavailability compared

Ranks 5 of 8 among vitamin c forms. Vitamin C (Liposomal) absorbs better — 95%. Compare all forms →

Magnesium Ascorbate 85

Magnesium Ascorbate: Non-acidic, Dual nutrients, Muscle support, Good tolerance

Food sources

before you supplement

Magnesium ascorbate is primarily supplemental Not found naturally in foods · 85

Too little

deficiency signs

Vitamin C deficiency symptoms:
Fatigue, poor immunity, slow healing
Plus magnesium deficiency symptoms:
Muscle cramps, anxiety, insomnia
Heart palpitations, headaches

Too much

toxicity signs

Mainly magnesium-related:
Diarrhea and stomach upset
Muscle weakness (high doses)
Low blood pressure
Breathing difficulties (extreme doses)
Vitamin C toxicity very rare

Who benefits most

athletes-active-individuals

Need both antioxidant support and muscle function

1000-3000 mg daily

stress-management

Both nutrients help with stress response and relaxation

500-2000 mg daily

cardiovascular-support

Synergistic benefits for heart and blood vessel health

1000-2500 mg daily

muscle-cramps-tension

Magnesium helps prevent cramps while C supports recovery

1000-2000 mg daily

sensitive-stomachs-need-magnesium

Gentle vitamin C plus essential magnesium

500-1500 mg daily

Where to buy it

compare forms first

Look for Vitamin C (Magnesium Ascorbate) at 500-2000 mg per serving. The form that matters here is Magnesium Ascorbate.

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What else affects it

Beyond other supplements

Alcohol

Depletes both vitamin C and magnesium

Increased excretion and impaired absorption

How it works

Same vitamin C mechanisms plus magnesium benefits
Magnesium serves as cofactor for 300+ enzymes
Buffered form prevents gastric acid stimulation
Magnesium enhances cellular vitamin C uptake
Synergistic cardiovascular and nervous system support
Combined antioxidant and electrolyte balance

Key findings

what the evidence supports

Gentler on stomach than ascorbic acid
Magnesium deficiency affects 50-80% of population
Synergistic cardiovascular benefits
Effective for muscle cramps and tension

Sources: NIH Examine.com · data reviewed 2026-08-02

Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →

Common questions

What are the benefits of Vitamin C (Magnesium Ascorbate)?

Documented effects: Dual nutrient supplementation; Enhanced stomach tolerance; Muscle and nerve support; Cardiovascular benefits. Provides both vitamin C and magnesium in one supplement

How much Vitamin C (Magnesium Ascorbate) should you take per day?

The common daily range is 500-2000 mg. By goal — maintenance: 500-1000 mg; therapeutic: 1500-3000 mg; magnesium content: 125mg magnesium per 1000mg vitamin C; laxative threshold: Above 400mg magnesium per day.

When is the best time to take Vitamin C (Magnesium Ascorbate)?

Divided doses with meals. First effects are typically reported within 24-48 hours for immune and muscle benefits.

What are the side effects of Vitamin C (Magnesium Ascorbate)?

At excessive doses: Mainly magnesium-related:, Diarrhea and stomach upset, Muscle weakness (high doses), Low blood pressure, Breathing difficulties (extreme doses). Safety rating at normal doses is 9 out of 10.

What should you not take with Vitamin C (Magnesium Ascorbate)?

Separate it from Calcium Excess, Alcohol by two to four hours. High calcium can deplete magnesium

Does Vitamin C (Magnesium Ascorbate) interact with medications?

Documented interactions with antibiotics-tetracycline, diuretics, ppi-acid-blockers. Discuss these with a pharmacist before combining.

How much Vitamin C (Magnesium Ascorbate) is too much?

The tolerable upper intake level is 2000 mg per day for adults, per NIH ODS. Above that, the risk of adverse effects rises: Mainly magnesium-related:, Diarrhea and stomach upset, Muscle weakness (high doses).

How do you know if you need Vitamin C (Magnesium Ascorbate)?

The marker is Plasma vitamin C + serum/RBC magnesium, optimal range Vitamin C: 50-114 μmol/L, Mg: 0.75-0.95 mmol/L. Common deficiency signs: Vitamin C deficiency symptoms:, Fatigue, poor immunity, slow healing, Plus magnesium deficiency symptoms:, Muscle cramps, anxiety, insomnia.

Taken for

43 Performance

Caffeine · Creatine Monohydrate · Whey Protein