Surely selective breading may bring harm. For example, tinkering with wheat to make it easy to process with machines resulted in kinds where gluten is less tole

Surely selective breading may bring harm. For example, tinkering with wheat to make it easy to process with machines resulted in kinds where gluten is less tolerant by humans [1]. What is important is speed and scale. I.e. making most plants less nutritional by 5-10% within 50 years is something very new. [1] https://ncbi.nlm.nih.gov/pubmed/20664999 https://ncbi.nlm.nih.gov/pubmed/20664999