How to Work Out Which Ingredients Your Skin Reacts To

If your skin flares but you don't know why, here's a practical way to narrow down your trigger ingredients without guesswork.

The principle

You cannot spot a pattern in chaos. The trick is to simplify, then reintroduce slowly, so each reaction points clearly at one product, and then at one likely ingredient.

The method

1. Reset: drop everything non-essential and use a plain fragrance-free cleanser and moisturiser for a week or two.
2. Reintroduce one product at a time, leaving several days between each so a delayed reaction lands on the right suspect.
3. Compare ingredient lists. If two products you reacted to share an ingredient, that overlap is your prime candidate. Fragrance and certain preservatives are the usual suspects.
4. Keep a record of product, date and what happened. Patterns are far easier to see written down.

Turn it into a list you can use

Once you have suspects, the useful step is checking every future product against them. ClearaScan stores your avoidance list and flags those ingredients on any product you scan, and it keeps a Reaction Journal to log flare-ups, a shared Care Circle so others can scan for you, and a Trusted Products list. (We co-founded ClearaScan and are not paid to mention it.) If symptoms persist, ask a dermatologist about formal patch testing.