Ketosis can be dangerous and is highly unnecessary. The key to losing weight is simple: burn more calories than you consume.
There is nothing wrong with consuming carbs (even in large amounts). The problem is when you don't use the energy it gives you and they turn into fat.
There isn't anything "dangerous" about ketosis. It's literally the way our bodies work. In paleolithic times, paleo man would've gone for extended periods of time without any carbohydrate sources, and would've relied on their own stored fat for energy. There wasn't any domesticated fruits or veggies back then, they were all wild and seasonal and generally unavailable in harsh winters. It's how our bodies are designed, this is millions of years of evolution at work here.
Losing weight is actually slightly more complicated that simply burning more calories than you consume. It's about
what you eat more than anything, and controlling carbohydrate intake. We Americans eat far, FAR too many carbohydrates -- mostly the bad kind. There isn't necessarily anything "wrong" with that, other than we are one of the fattest countries in the world with an obesity epidemic spiraling out of control.
By the way -- I'm in keto right now. It's getting easier. I also eat 5 times per day while remaining in ketosis.