Skip to content

24-Hour Magnesium Intake Measurement

Published: August 9, 2026Updated: August 16, 2026

This test measures the total amount of magnesium you consume over a 24-hour period, helping assess dietary magnesium intake.

Quick summary

["Understanding your magnesium intake helps identify dietary habits and potential deficiencies."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
81006-9
Short code
Magnesium intake 24h Measured
Synonyms
Magnesium intake 24h Measured
Category
electrolyte
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
1.7
Ref high
2.2
Critical range
1 N/A – 5 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
measured
CPT
83735
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Matters

Magnesium is an essential mineral that plays a key role in many bodily functions, including muscle and nerve function, energy production, and maintaining healthy bones. While blood tests measure magnesium levels in your body, this test focuses on what you eat and drink over a day.

How It Works

You’ll be asked to record all foods and beverages containing magnesium (e.g., nuts, leafy greens, whole grains, dairy, and certain meats) for 24 hours. A healthcare provider or dietitian may guide you through the process to ensure accuracy.

What to Expect

No special preparation is needed, but you may be asked to avoid certain supplements or medications that could interfere with the measurement. Follow your provider’s instructions carefully.

Common Uses

This test is often used to evaluate dietary habits, especially in people with suspected magnesium deficiency, chronic kidney disease, or those on strict diets (e.g., low-sodium diets). It can also help identify dietary patterns that may contribute to health concerns.

Reference range

Adult: 1.7-2.2 mg/dLN/A

Specimen: serum

No special preparation required. Stay well hydrated.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

24-Hour Magnesium Intake

Frequently asked questions

What causes someone to get this test?
Your doctor or dietitian may recommend this test if you have symptoms like muscle weakness, irregular heartbeat, or frequent cramps, or if you’re on a diet that limits magnesium-rich foods.
How long does it take to get results?
Results are typically processed within a few days to a week, depending on lab workload and follow-up instructions from your provider.
Can I change my diet while waiting for results?
Yes, but avoid making drastic changes. Focus on balancing magnesium intake with other nutrients while awaiting results to avoid misleading interpretations.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy