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Trusted to do 100,000+ tests and consultations per month.
Trusted to do 100,000+ tests and consultations per month.
Magnesium Blood Test

 


MAGNESIUM BLOOD TEST

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£49.00
£49.00 - £49.00
£49.00
£49.00 - £49.00
1 BIOMARKER
1-2 DAYS
INSTRUCTIONS
FAQ

Measure the levels of magnesium in your blood that can help detect conditions such as preeclampsia, or conditions affecting kidney or intestine function.

Simple and accurate blood test from a laboratory you can speak to.

STEP 1 - CHOOSE YOUR SAMPLE COLLECTION OPTION
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GABBY LOGAN - HEALTH AMBASSADOR FOR ONE DAY TESTS

Our amazing Health Ambassador, Gabby Logan, MBE, talks about the importance of preventative testing and why it is important to find the problem before it becomes a problem.

And the best way to do this? Find our what's in your blood, direct from a laboratory you can speak to, at One Day Tests.

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MAGNESIUM BLOOD TEST OVERVIEW

The magnesium blood test measures the amount of magnesium in your bloodstream, an essential mineral that supports many critical bodily functions.

Magnesium plays a key role in nerve and muscle function, heart rhythm, bone strength, and energy production. It also helps regulate blood pressure and supports a healthy immune system.

Although most magnesium in the body is stored in bones and tissues, a blood test can give a helpful snapshot of your magnesium status.

SHARE YOUR HEALTH STORY

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MAGNESIUM BLOOD TEST

Magnesium is a vital mineral and electrolyte that plays a key role in keeping your body functioning properly. It is involved in over 300 biochemical reactions, supporting essential processes such as muscle and nerve function, heart rhythm regulation, blood pressure control, bone health, and energy production.

Magnesium also helps maintain the balance of other minerals in the body, including calcium and potassium.

1 Biomarker

  1. ELECTROLYTES

    - Magnesium

  2. UPGRADE

    Need more biomarkers? Check out our Electrolytes Blood Test.

  1. TURNAROUND TIME

    We are extremely fast, with some results available within hours and others within a working day or less, from the time your sample is in our lab. However, this is not a guarantee and should not be taken as such. This is the guideline turnaround time that can be shorter or longer.


    THIS IS NOT A GUARANTEED TURNAROUND TIME.


    We are extremely proud of our very short turnaround times and a very efficient laboratory processes, you will start receiving results as soon as they are available and have completed clinical validation.


    Whilst we accommodate the shortest of time scales, with some results available within hours, for this particular test the usual turnaround time is: 1-2 working days.

  1. WILL I HAVE A GENERAL EXPLANATION OF MY RESULTS?

    Yes, our doctors put a huge amount of effort into your online Health Dashboard, which will have explanations of what each biomarker is, the normal reference ranges and what it means if you are outside of them.


    This service is included in the price of all our tests.

  1. CAN I SEE A GP TO DISCUSS MY RESULTS?

    Yes, usually the same or next day.


    One Day Tests has a fantastic clinical team of consultants and GPs. Once you have your results you can book an online video consultation to discuss your results.


    Our clinical team consists of practicing NHS and private GPs, who work closely with our laboratory and can tell you what your blood test results mean for you. Having an integrated laboratory and GP services makes your health journey seamless and extremely efficient.


    This service is not included in the price of the test, it is charged separately, should you wish to book it.

DOCTOR'S COMMENTS

Hi, I am Dr. Adam Staten and here's my view on this test as a GP and Clinical Director at One Day Tests.

DR. ADAM STATEN - GP VIEW AND RED FLAG SYMPTOMS

From a GP’s perspective, the magnesium blood test is a useful tool for assessing electrolyte balance and overall metabolic health. Magnesium is essential for nerve function, muscle control, and maintaining a healthy heartbeat. If you’re experiencing symptoms like muscle cramps, weakness, fatigue, or irregular heartbeat, this test can help us determine whether a magnesium imbalance might be contributing to your symptoms.

I may also recommend this test if you have certain chronic conditions, such as diabetes, kidney disease, or digestive issues that affect how your body absorbs or excretes magnesium. It’s also helpful if you’re taking medications that may lower magnesium levels, such as diuretics or long-term antacids.

Red flag symptoms for the Magnesium Blood Test

Your Results and Health Dashboard

The results of your Magnesium Blood Test will be emailed to you as a secured PDF file, ready for your GP and will also be uploaded to our Health Dashboard area of the website. It’s a unique and powerful tool, powered by our in-house clinical analysis research, to match your biomarkers across test panels and symptoms, as well as provide clinical commentary on all individual biomarkers you tested for.

The health dashboard will also provide "panel level" commentary - a birds eye view of the biomarkers that were tested. This feature allows you to view your test results and clinical commentary, and compare them to previous results, giving you a clear understanding of how your health is progressing.

By using the Health Dashboard, you can identify changes in your biomarkers and make necessary adjustments to your lifestyle. This added value is immense, as it empowers you to monitor your health and make informed decisions about your well-being.

It's free and is available with all of our tests.

SAVE ON CONTINUOUS MONITORING WITH OUR SUBSCRIPTION PLAN

The best way to look after your health is to do so regularly. This is easy to do with our continual monitoring plans which give you a discount on future blood tests. You choose the frequency and we'll do the rest.

When you purchase a subscription, we will deliver your home test kits or allow you to book appointments in line with your chosen frequency. You will be able to track your biomarkers over time in our powerful Health Dashboard, where results will be automatically updated for you. There is a minimum of 3 tests with any subscription, after which you can pause/restart/cancel at any time.

SPECIAL INSTRUCTIONS

Hi, I am Stefania Brown, I am the Laboratory Manager at One Day Tests and here are the lab's special requests for the Magnesium Blood Test.

SPECIAL INSTRUCTIONS

The results may be affected by the following:

Magnesium supplements, Diuretics, Proton pump inhibitors (e.g. omeprazole), IV drips and any other supplementation

Clinic appointment - how to prepare for the Magnesium Blood Test

If you are coming into one of our clinics for the test, this is what you need to do before you arrive:

  • Read the instructions in the SPECIAL INSTRUCTIONS section
  • Drink plenty of water about an hour before the appointment.
  • Avoid coffee/tea/energy drinks. Water is good!
  • That’s it! We’ll do the rest.

Home test kit - how it works with the Magnesium Blood Test

Our blood test kits are simple and convenient.

The most important step in doing a blood test at home is to read the instructions very carefully. The process is very simple, but there are a few pitfalls you need to be aware of - you will save yourself a lot of time if you do it right the first time around!

  • Full printed instructions will arrive with your kit - please read them carefully.
  • Drink plenty before taking the sample and warm your hands up in the sink with warm water for a few minutes. This will make your blood flow much better.
  • Fill the tubes to the top line. We don’t need much blood; filling tubes to the top line is about 15 drops of blood.
  • Post the samples on the same day you take them, before midday, Monday to Thursday. If you post it any other time it might get to us late or be stuck at a sorting office over the weekend. You will then have to do it again.
  • Package the sample in the same box the kit came in. Otherwise, Royal Mail or DPD will reject it. The sample tubes go into a pouch, then into a cardboard box, and then into a return envelope. All of this is provided in the kit: please use it.

We look forward to receiving your sample in our lab!

HOW OUR HOME KITS WORK

How the finger prick home blood test kit for Magnesium Blood Test works - from Dr. Adam Staten

Follow our step by step instructions on how to take your sample quickly and easily using the blood sample collection finger prick test.

WHY CHOOSE US?

Hello! My name is Dr. Vinesh Mistry, I am part of the GP team here at One Day Tests and here is why you should trust us to test your blood.

QUICK AND ACCURATE RESULTS DIRECT FROM A LABORATORY.

We run our own regulated laboratories and our own accredited clinics. We manufacture our own approved home sample collection kits. Your results are looked after by our fantastic clinical governance team and our super-talented biomedical science team.

When you book your test with us - you book directly with the lab. This means accuracy and responsible duty of care, direct access to the provider and extremely fast turnaround times.

Finally, our customer services rock! You can ask the lab a question any time or you can speak to a real human. You can email us on hello@onedaytests.com or give us a call on 0127 309 2844.

FREQUENTLY ASKED QUESTIONS

Hi, I am Lana Nela, Lead Nurse, and here is what we are frequently asked about this test.

FREQUENTLY ASKED QUESTIONS

Here are some of the most frequently asked questions about the Magnesium Blood Test.

Can I have low magnesium even if I eat a healthy diet?

Yes. While diet is important, certain conditions like digestive disorders (e.g. Crohn’s or coeliac disease), diabetes, or the use of medications like diuretics can impair how your body absorbs or retains magnesium. So, even with a balanced diet, you can still develop a deficiency.

What’s the difference between a blood magnesium test and a red blood cell (RBC) magnesium test?

A standard magnesium blood test measures the amount in your serum, which only reflects a small portion of total body magnesium. Some specialists may request an RBC magnesium test, which measures levels inside red blood cells and may provide a more accurate picture of long-term magnesium status, though it's not usually used in standard investigations.

Can magnesium levels affect heart health?

Absolutely. Magnesium plays a key role in maintaining a normal heart rhythm. Both low and high levels can lead to arrhythmias (irregular heartbeat) and other heart-related symptoms. That’s why this test is often recommended for people with cardiac concerns or those on medications that influence electrolyte balance.

WHY HAVE THE TEST?

Hi, I am Nader Eldarf, I am a Biomedical Scientist in our laboratory and here is why it's important to take this test.

  1. WHY HAVE THE MAGNESIUM BLOOD TEST?

    The magnesium blood test is important because it helps detect imbalances that can significantly affect your muscles, nerves, heart, and overall health.

    Magnesium is a vital mineral involved in hundreds of bodily processes, including energy production, muscle contractions, nerve transmission, and maintaining a normal heart rhythm.

    Even a slight deficiency or excess can lead to noticeable and sometimes serious symptoms.



    Measuring magnesium levels is especially crucial if you have conditions like kidney disease, diabetes, gastrointestinal disorders, or are on medications that affect magnesium absorption or excretion (such as diuretics or certain antacids).

IS THIS TEST RIGHT FOR YOU?

Hi, I am Sandeep Patel, I am the Laboratory Director at One Day Tests. Here are the symptoms that you may wish to address with this test.

  1. IS THE MAGNESIUM BLOOD TEST RIGHT FOR YOU?

    The magnesium blood test may be right for you if you’re experiencing symptoms that suggest your magnesium levels are too low or too high.

    Common signs of low magnesium (hypomagnesaemia) include muscle cramps, fatigue, weakness, tremors, irregular heartbeat, or even numbness and tingling.

    On the other hand, high magnesium levels (hypomagnesaemia), usually only seen in people with kidney problems or those taking supplements or certain medications, can cause nausea, low blood pressure, confusion, or slowed reflexes.



    Your GP might also recommend this test if you have conditions or treatments that are known to affect magnesium balance, such as chronic diarrhoea, diabetes, kidney disease, or use of diuretics or proton pump inhibitors.

  1. SYMPTOMS AND TAGS

WHY ARE BLOOD TESTS IMPORTANT?

Health monitoring is very important, you are in charge of your health - look after it.