Your diet in the 24 hours prior to an 18F-FDG PET-CT scan directly dictates the clarity of your diagnostic images. Failing to adhere to dietary rules can cause high background muscle and heart uptake, obscuring tiny tumors.
Pre-Scan Diet Golden Rules:
• 24 Hours Before: Low-carb, high-protein diet (Eggs, grilled chicken, paneer, tofu, green salads). Avoid rice, rotis, sugar, fruits, and sweets.
• 6 Hours Before: Strict Nil-by-Mouth except plain water.
• No Chewing Gum or Mints: Even sugar-free gums stimulate salivary and masseter muscle uptake.
• Hydration: Drink 2-3 glasses of plain water before reaching the centre.
Why is Carbohydrate Restriction Crucial?
When you consume carbohydrates or sugars, your pancreas produces insulin. Insulin signals your normal skeletal muscles and adipose tissues to soak up glucose. If 18F-FDG is injected while insulin is elevated, the tracer floods into healthy muscles rather than the tumor, making tumor identification difficult.
Clinical Dietetics Team
PET-CT Patient Care Division
Dedicated to high-precision nuclear oncology imaging and patient-centric diagnostic safety at Molecular Diagnostics & Therapy Indore.