How healthy is real sugar?

Not at all.

According to endocrinologist Dr Robert Lustig, it's a toxin, and he has scientific evidence to back up his claim.

Table sugar has no nutritional value. None. However, it has a powerful effect on the pleasure center of the brain, lighting it up like a Christmas tree, almost like cocaine. That's why it's so addictive.

• Sugar has a similar effect on the brain as cocaine - Business Insider

But it gets even better. Since table sugar is 50% fructose, and fructose can only be stored as fat in the liver until it's converted to glucose at a later date, the liver of someone on a high sugar diet ends up like this:

The liver of a high sugar consumer is indistinguishable from the liver of an alcoholic. Fatty liver leads to insulin resistance, metabolic syndrome, and eventually type 2 diabetes.

In addition, sugar is highly inflammatory and has been linked to heart disease, cancer, an Alzheimer's, to name just a few ailments.

• Eating too much added sugar increases the risk of dying with heart disease - Harvard Health Blog

The average American consumes 60 to 75 lbs of sugar per year, most of it coming from ultra-processed food.

Processed foods, calories and nutrients: Americans' alarming diet - American Institute for Cancer Research

https://www.aicr.org/resources/blog/processed-foods-calories-and-nutrients-americans-alarming-diet/