There are few long-term (for first-world babies) once you adjust for socioeconomic and socioenvironmental factors: http://researchnews.osu.edu/archive/sibbreast.htm; http://www.slate.com/articles/health_and_science/medical_exa... http://www.ntnu.edu/news/breastfeeding; http://www.skepticalob.com/2014/02/hold-the-guil-new-study-f... http://time.com/99746/its-time-to-end-the-breast-is-best-myt....

I would put "huge benefits to breastfeeding" right up there with medical myths that have been recently debunked, such as "dietary cholesterol raises blood cholesterol" or "salt causes hypertension."