Sugar is sugar.

Complex carbs simply get digested slower than simple carbs (from Healthline and medicalnewstoday).

The impact on your body is the same: no ketosis, low quality energy source to your brain, and spike in blood sugar (albeit lower than with simple carbs).

Sugar is unhealthy, period.

But since it's the number 1 consumed drug in the world, no one in the mainstream will ever tell you that.

For more info, check out the keto and carnivore crowd.

Diet Doctor and Revero are great places to start.