I put a hot mug directly on my grandmother’s old end table. No coaster. Twenty minutes later there was a white ring burned into the finish — the kind that makes your stomach drop because you know you just ruined something irreplaceable.

I panicked. I googled. I found a method involving mayonnaise that sounded completely fake. Mayonnaise removes white water rings from wood furniture. It works because the oil in the mayo penetrates the finish and displaces the trapped moisture. I have now used this trick four times and it has not failed once.

The mayonnaise method, step by step

Dab a small amount of regular mayonnaise onto the water stain. Not Miracle Whip — actual mayo with oil and egg. Spread it into a thin layer covering the entire ring plus a little extra around the edges. Leave it for at least two hours, or overnight for bad stains.

Wipe it off with a clean cloth. The white ring should be significantly faded or completely gone. If there’s still a faint trace, do a second application. My worst stain — the hot mug ring — took two overnight treatments but it came out entirely.

The science: white water rings are caused by moisture trapped in the finish layer, not the wood itself. The oil in mayonnaise works its way into the finish and pushes the water out. It’s the same principle as using olive oil or petroleum jelly, but mayo has the right texture to stay in place for hours.

When mayo does not work

If the ring is black or dark brown, not white — that is different. Dark rings mean the water has penetrated past the finish and into the actual wood. Mayo will not help. For black rings, you need to strip and refinish, or use oxalic acid (wood bleach) — both of which are a whole different project.

Also: if the wood feels rough or the finish is visibly peeling, the moisture damage is structural. Mayo only works on trapped-moisture stains in an otherwise intact finish.

Alternative for people who hate the mayo idea

Put a clean white cloth over the stain. Set your iron to low heat (no steam). Iron over the cloth for 10-15 seconds. Lift and check. Repeat until the ring fades. The gentle heat draws the moisture out of the finish and into the cloth. This method is faster than mayo and works equally well for most white rings.

I prefer the mayo method because I cannot accidentally burn my furniture with an iron. But if you’re in a hurry, the iron trick takes five minutes instead of overnight.

• White rings (trapped moisture): Mayo overnight OR iron + cloth method
• Dark/black rings (wood damage): Needs refinishing — mayo won’t help
• Peeling finish: Structural damage — call a furniture restorer