How to clean MacBook body scratches? Toothpaste?

I vote for "let it be." You are not looking at bare aluminum.

A bit of manufacturing info from someone who worked in an industry that made aluminum products:

To protect the metal from staining and corrosion, almost all aluminum products go through a final process called anodization. This produces a clear aluminum oxide layer that resists environmental influences that can attack bare aluminum and a bit of surface hardening that helps mitigate minor scratching but not gouges.

The coating is developed in an electro-chemical bath. That added layer is what gives the MacBook Pro case that "slick" feel when you run your hand across it. Bare aluminum has a more sticky feel. If color is required (like Apple's "Space Gray" or "Rose Gold"), special dyes can be added to the process.

Skip ahead to today. Any effort on your part to eliminate the scratches will also eliminate the oxide layer and the protection it affords. Because you cannot work on only the narrow scratch, you will end up with a wider unprotected patch of bare aluminum much larger than the area of original damage. You cannot restore the original look and feel that Apple put on the case.

The larger area of bare aluminum you create in attempting the repair will, with time, turn dark and and ugly. You will have made the problem much, much worse.

Allan

Leave the scratches. The repair may look worse. The scratches just indicate use and experience.

Automotive rubbing compound has a mild abrasive (which is the part that does the work when you use toothpaste, it is not a chemical process).

Metal polish is for removing tarnish, so it always contains ammonia, but its abrasive and absorbents content varies by manufacturer. Different types for different metals are generally the same formula in a different bottle. Some have no abrasive, some have a lot.

I've tried cleaning a lot of metal objects. The location worked on always looks different in the end than the spots not worked on. Feel free to do as you wish. Personally I do not have the patience or time to take on such a task that may turn out "blotchy". Same as when you spot clean anything. I'm sure with enough time and effort you'll get it to look pretty good but I'd rather live with the scratches.

BobTheFisherman has been the voice of reason and wisdom and experience through all of this.

I have offered the types of products that contain stronger abrasives than the very mild abrasive in toothpaste, but your mileage WILL vary. The "repaired" area will always look somewhat different. How different depends on how much you are willing to work at it.