In my amateur opinion, yes. The principal difference is pleasure: sugar and other sweet things are more pleasurable to eat than bland foods like white bread.

https://www.nature.com/articles/nn.4224

This is important because eating when you're not hungry is a huge risk factor for obesity. It's not rewarding or fun to eat bland foods when you're not hungry, but it is still fun to eat candy when you're not hungry. This can be particularly problematic when sugary foods become a form of hedonic substitution or a coping strategy in bored or depressed individuals. Additionally, there are some studies which suggest that the tongue may become desensitized to sweetness when habitually eating sugary foods, potentially motivating individuals to choose sweeter foods at meal times:

https://onlinelibrary.wiley.com/doi/abs/10.1111/ejn.13149

White bread isn't good for you, but it lacks these effects.

Sugar is 50% glucose 50% fructose while white bread is only long chains of glucose, unless sugar was added to it too (only a thing in the US AFAIK).

Sugar is needed for yeast to raise the dough. It's common everywhere not in the US alone. I'm in Europe and most bread has sugar added during preparation. Small amounts but still sugar.

Added sugar is not necessary for yeast. The yeast is breaking down and using the carbs naturally present in wheat. The simplest breads, like french baguettes, are only made with flour, water, salt and yeast. Sugar is added to many commercial breads because it can make production easier and more consistent and sell more to consumers, but it's not added because it's necessary.

It's less than one flat teaspoon per loaf, and most of that is metabolised by the yeast. You can do without it, but it takes much longer to rise.

Ok, of the carbs in white bread here there is 0.6% sugar. That's completely negligible and now what I'm referring to at all. I am talking about added sugar where it will be 10-20% of the carbs in the white "bread" (I consider that pastry :D).

The yeast metabolises that sugar.

I think people are talking about adding sugar for taste, beyond what the yeast can metabolise, which is common in US food culture but not generally elsewhere.

Check out Czech bread. Completely sugarless.

Yes. Complex carbs are chains of glucose. Sugar has fructose which is much worse for you than glucose (assuming you are not diabetic of course).

But they do contain the same amount of calories per gram, so obesity is unaffected.

That’s only true if you eat the same quantity of both. The other problem with sugar is that it doesn’t satisfy hunger as effectively as starch so you typically end up consuming more of it. The best bang for the caloric buck in terms of hunger satiation is actually fat and protein.

Don't forget fiber. Honestly, a good, high-fiber carbohydrate is about as good as you can get for satiety/gram, except maybe for fat.

I think you'll find a bowl of oatmeal hard to beat for satiety, and that's super high in carbohydrates (~70% carbs). Compare that to a glazed donut, which has fewer carbs and more fat, and I think you'll find that the oatmeal is more satisfying.

I think most diets ignore perhaps the most important part of successfully losing weight: feeling reasonably full. IMO, the macros don't matter nearly as much as the satiety of the food you eat, since feeling full is a huge help when trying to avoid excess calories.

Some difference - definitely. Does it count as "much"? Depends on your definition of "much". Glycemic index is interesting starting point to look into this.

Not all white bread is identical either. Sugar content may vary a lot from brand to brand. Glycemic index too.

No the body will convert all sugars / carbs the same. The only difference is how fast it will get in your blood.

Not all sugar is actually processed by the body the same though.

Fructose gets processed in the liver whereas glucose goes into the blood stream triggering insulin response.

Other very fine points are glycemic index, for example a low glycemic index food breakdown to glucose, bypassing the liver, but is absorbed into the bloodstream relatively slowly for glucose and minimizes the insulin spike/response promoting more stable blood sugar levels.

Yes that's definitely true I meant they will end up as the same end result. The fast sugars will end up causing you want more of it again in a shorter amount of time so it is ofcourse better to eat veggies instead of a candy bar to get your required energy.

And thats the problem. Insulin spikes are bad for you.

That's only half the story. Simplest sugars (monosacchrides like fructose) get absorbed almost instantly in your stomach/instentine while more complex sugars/carbs (disacchrides and starches) get finally broken down and absorbed further down your intestine. This can have a dramatic impact on your biome.

Fiber content, caloric density, and palatability.