Even if you do throw out old boxes of Chinese food before it goes bad, you (most likely) aren’t rigorous about cleaning out your entire fridge.
Start by taking everything out (yes, we mean everything) and throw out anything that is old or has a strange smell and/or resembles something of a science project (e.g. mold).
Remove the drawers and shelves from the fridge and wash off any dirt, crust or old food. You can also scrub difficult-to-get areas with a scrub brush and/or an old toothbrush.
Throughout the spring and summer get in a habit of regularly cleaning your fridge and freezer by making it a part of your normal cleaning schedule (about twice a month).
If you have small jobs such as refrigerator cleans or cupboard cleans and no extra time, book a one hour blitz with Your Maids, or get a thorough one off clean.