Each generation is getting taller than the last. Maybe this has plateaued now, but at least in the last few generations.
I can only image that this is because of a more energy dense diet, so I think that sweets more than anything over time would add to final height, not subtract from it.
As for alcohol and nicotine, studies have shown that both can have a negative impact on bone growth.
Nicotine as much as an inch according to a Canadian study.
As for alcohol I could not find a study saying by what amount, however there was a study that showed evidence that the effect is caused by depressing the release of growth factors from the pituitary gland.
I guess that makes sense as alcohol depressing the central nervous system and the gland is directly connected to the brain, and the brain signals the release of hormones from the gland.