From Longman Dictionary of Contemporary Englishdo somebody a/the world of gooddo somebody a/the world of goodto be very good for someone’s health or mental state A bit of fresh air and exercise will do her a world of good. → world
Examples from the Corpus
do somebody a/the world of good• Not only do they do you a world of good if you drink them but they also have cosmetic uses.• He could become so unaccountably miserable that a small amount of collusion some-times did him a world of good.• But physically - this type of exercise will do you the world of good.• All the family can enjoy eating the low-fat way and it will do everyone a world of good.• Come on a Club 18-30 holiday and there's every chance it will do you the world of good.• A week by the ocean will do you a world of good.• All of them stressed that a holiday would do Valerie the world of good.• A good run in pastures new would do you a world of good. 