What is a healthy weight for a male 5ft.7in.

Variable. The adult standard for a healthy weight includes those with a body mass index from 18.5 to 24.9. At 5'7" this equates to between118 and 160. The BMI assumes average bone structure and muscularity so it is not a great gauge for individuals with different physiques.
Body knows. You body seeks the weight it wants to be when you stop eating bread, sugar, potatoes, artificial sweeteners, and most fruit juice. Weight/belly fat put on by these foods is not healthy.