I don't know. I have not tried this myself but I have come across two recipes for using avocado to strengthen and nourish hair.
Combine 1 avocado, 1 egg yolk and 1 tablespoon of olive oil. Mash the avocado until smooth and mix in egg yolk and oil until well combined.
1 ripe avocado, 2 tablespoons yoghurt, 1 gee, 1/2 teaspoon rosemary oil, 1 tablespoon jojoba oil.
Blend all the ingredients together until smooth and well combined.
The idea is to work it into the scalp. Massage the mixture into the scalp and hair. Leave it in for about 20 minutes. Wash out with shampoo and conditioner.
It is supposed to help the hair regain elasticity, shine and body.
While I haven't tried this I can quite well believe that it could have very beneficial effects due to the wonderful nutrients in avocado.
Natural beauty aids from the kitchen are useful though this one sounds messy. If you try this one let us know how it goes and whether you liked it.