Radiology/pet scan


Thank you for your time, Delia.  I am a six year cancer survivor who has to do an occasional pet scan.  I have had probably over 20 scans in the past years.  Recently my sister told me that usually people are told not to eat carbs before a pet scan.  I was never told this but now I wonder if I should avoid carbs.  Have you ever heard this before?  Thanks again for your time.

Hello, Tanya.

A quick search of the internet gave me lots of information about special diets for PET scans. From , here's an explanation about why a low carb diet is recommended:

Your PET-CT scan provides a picture showing where certain molecules are in your body; in most cases, where glucose or “sugar” is located. This is greatly affected by the level of sugar in your blood, therefore your diet the day before the scan makes a BIG difference in the quality of pictures that we get. Obviously, it is very important for you to get the best scan possible, so please try to follow this diet as closely as possible.

Many of the websites I found regarding a special diet for PET scans do recommend a low carb diet. For the best results, you should contact the facility where you will go for your PET scan to ask for their PET prep instructions.

Hope this helps,


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Delia White


I am not qualified to interpret diagnostic imaging or to diagnose disease. Please consult a physician for that information. I am the photographer. I can tell you what to expect during most MRI, CT and X-ray procedures.


I now have more than 30 years experience in diagnostic imaging. My specialty is MRI. I am also very familiar with CT and the way we used to take x-rays (everything's digital now)!

I received my Bachelor of Science degree in Radiologic Technology.

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