When preparing for an MRI scan, patients often wonder if they need to avoid certain foods or drinks beforehand. The short answer is yes, there are some dietary restrictions prior to an MRI. Understanding what you can and cannot consume will ensure your test goes smoothly and produces high-quality images.
Why food and drink restrictions are necessary before an MRI
MRI scanners use powerful magnets and radio waves to generate detailed images of the inside of the body. The scans detect signals from hydrogen atoms in water and fat. Anything with a high water or fat content will show up clearly on the scan. Metal can also interfere with the magnetic field used by the scanner.
For these reasons, precautions need to be taken with what you ingest before an MRI. Certain foods and drinks are restricted because they could:
- Obscure images due to their high water or fat content
- Cause artifacts that degrade image quality
- Pose a choking hazard if you need sedation
- Interact with contrast agents used for enhanced imaging
Following dietary guidelines helps produce the most accurate MRI results and prevent complications.
Standard MRI food and drink restrictions
Here are the standard recommendations on what not to eat or drink before an MRI in most cases:
For at least 24 hours before
- Avoid high-fiber foods – Fiber adds bulk and gas to stool in the intestines that can distort abdominal images.
- Avoid withdrawol-causing substances such as: There are many substances to withdraw from in the typical human body, this includes alcohol.
For at least 8 hours before
- Do not eat any solid food – Solids take longer to digest and clear the stomach. Liquids are preferable.
For at least 2 hours before
- Avoid dairy products – Dairy is high in fat which can interfere with imaging.
- Do not drink coffee, tea, or other caffeine – Caffeine is a diuretic that can cause frequent urination and the need to interrupt the scan.
For at least 1 hour before
- Do not drink clear juices – Juices still have a high water content.
- Avoid gum, cough drops, mints – Anything with sugar alcohols like sorbitol, mannitol, and xylitol can cause cramping and diarrhea.
Allowed up until scan time
- Clear liquids – Small sips of water, clear broth, plain gelatin, popsicles, and non-pulpy juices.
- Medications – Only essential prescription medications should be taken with a sip of water.
Exceptions for certain MRI scans
The standard dietary restrictions may be adapted based on the area being imaged and whether an MRI contrast agent is used. For example:
Brain or neck MRIs
- No solid food for 2-3 hours prior.
- Contrast is often given, so restrictions may be longer.
MRIs with contrast
- May need to fast for up to 12 hours beforehand.
- Often no solid foods for at least 4 hours prior.
- Reduced liquids as well, only sips allowed.
MRIs of the abdomen or digestive system
- No solid food for 6-8 hours before.
- Laxatives or enemas may be prescribed to clear bowels.
What happens if you eat before an MRI?
Consuming solid food too close to an MRI can negatively impact the scan in several ways:
- Food can obscure images of the abdomen and digestive tract.
- There is a higher risk of vomiting and aspirating if anesthesia is used.
- Food in the intestines can cause artifacts on images.
- Eating may cause changes in organ shape and function.
Drinking clear liquids too close to the scan can also lead to suboptimal images. Technologists may make you reschedule your MRI if you do not follow the necessary dietary precautions.
Tips for fasting before an MRI
Here are some useful tips to make fasting easier before your MRI appointment:
- Stay well hydrated with allowed clear fluids.
- Opt for lighter meals the day before your scan.
- Avoid overexerting yourself when fasting.
- Suck on hard candy if you get hungry.
- Bring a book or headphones to distract yourself while waiting.
- Plan rest breaks if fasting for over 6 hours.
- Set a timer or reminders so you don’t accidentally eat too soon.
Can you drink coffee before an MRI?
It is best to avoid caffeine from coffee, tea, soda, and energy drinks in the 2-3 hours prior to an MRI scan. Caffeine is a diuretic that can cause the need to urinate frequently. This may require interrupting the MRI procedure.
Caffeine also stimulates the intestines, potentially causing bowel motion artifacts on images. Consuming coffee with cream or sugar adds fat and fluid that are also undesirable.
If your MRI is late in the day, you may be advised to avoid caffeine for most of the day leading up to your appointment. Check with your doctor or MRI technologist if you have any doubts about consuming caffeine beforehand.
Are mints or gum allowed before an MRI?
Chewing gum, cough drops, mints, candy, and breath mints should be avoided for at least 1 hour prior to undergoing an MRI scan. These products contain ingredients like sorbitol, mannitol, and xylitol which are sugar alcohols used as sweeteners.
Sugar alcohols are poorly absorbed by the body and can have a laxative effect, causing diarrhea, bloating, and intestinal cramps. This can lead to discomfort and poor image quality if scanning the abdomen. It is best to avoid any gum or candy before your appointment.
Can I drink alcohol before an MRI?
Drinking alcohol is not recommended for at least 24 hours prior to an MRI scan. Alcohol dehydrates the body which can cause side effects. Dehydration also makes lying still for a long period more difficult.
Alcohol can interact with medications you may be given for sedation or contrast. It also may alter organ function, leading to inaccurate scan results. Heavy alcohol use can cause liver abnormalities that might require a rescheduled MRI after a period of abstinence.
Check with your physician if you have concerns about abstaining from alcohol before your test. Be sure to disclose any heavy or frequent drinking so proper preparations can be made.
Are herbal supplements allowed before an MRI?
Most doctors and radiologists recommend stopping herbal supplements and natural remedies at least 1-2 weeks before an MRI scan. Compounds in these products can have effects on MRI results and may also interact with contrast dye.
For example, herbs that act as diuretics or laxatives like dandelion, aloe, senna, or ginger could distort images. Oil-based supplements may also interfere with quality. Turmeric, ginkgo, ginseng, garlic, and others may heighten the risk of bleeding.
Check with your MRI provider for specific advice about your supplements, especially if they are required for a medical condition. It is necessary to weigh the potential risks versus benefits of stopping or continuing supplements.
Can I chew nicotine gum before an MRI?
Nicotine gum is generally not recommended within 1-2 hours of undergoing an MRI scan. As with regular chewing gum, nicotine gum poses issues due to the ingredients and chewing motion.
Nicotine gum contains sweeteners like mannitol and sorbitol that can have laxative effects and cause cramping or diarrhea. The act of chewing also stimulates the digestive system which can degrade abdominal images.
Nicotine itself can affect vascular flow and organ function, potentially altering scan results. Talk to your provider if you have concerns about abstaining from nicotine gum before your MRI appointment.
What can I eat after an MRI with contrast?
Contrast agents containing gadolinium are commonly used in MRIs to enhance the visibility of internal structures. There are often dietary restrictions following an MRI with contrast.
Many radiologists recommend waiting at least 30 minutes after the procedure before eating or drinking anything. Then you may be able to consume clear liquids. A full meal may be allowed after 1-2 hours.
This allows time for the contrast to distribute throughout the body without interference. The wait also enables technicians to monitor for potential side effects from the contrast dye.
If you have a history of allergies or reactions to contrast agents, your provider may want you to wait longer before consuming anything by mouth. Always follow instructions from your MRI staff about eating after a contrast-enhanced scan.
Key takeaways
- Avoid high-fiber foods and alcohol for 24 hours before an MRI.
- Do not eat any solid food for 8-12 hours prior to the scan.
- Stop consuming caffeine and dairy 2-3 hours beforehand.
- Only drink small sips of clear liquids in the 1-2 hours before the MRI.
- Chewing gum, mints, cough drops should also be avoided.
- Dietary restrictions help maximize image quality and prevent complications.
- Talk to your provider about any special conditions like diabetes or contrast use.
- Following preparation guidelines ensures your MRI goes smoothly.
The bottom line
MRI scanners are sensitive to anything that alters the magnetic field or introduces artefacts. For this reason, it is crucial to carefully follow dietary restrictions before your scan. Avoiding solid food, dairy, caffeine, and some medications or supplements for a period ensures your test produces high-quality results free of distortions.
Understanding exactly what you can and cannot consume prior to an MRI ensures things go smoothly. Follow instructions from your provider and MRI staff to get the most accurate images possible during your scan.
