A couple things will happen if you do not eat sugar for 3 weeks ,see below:
Your brain gets a hard reset. When you consume something you build up tolerance to it so you seek out more of it.
Like scented candles they ‘stop smelling nice’ after a day or two, or cat piss. Cat piss stinks, but that’s not because the scent goes away but your brain filters it out as it gets used to it.
So anything sweet you eat will taste incredibly sweet afterwards as you’ve reset your brain and you can taste the fistfuls of sugar in it. Someone who quitted sugar for a year
He said:
'I quit sugar for a year. I still have the odd bit of chocolate now and again. I lost tons of weight. I then tried to drink a can of cola 140 calories fist full of sugar. It was overwhelming and it tasted horribly sicky sweet. I tossed it away after a mouthful and spat it out.'
Second:
You get thinner, sugar has enormous amounts of calories in it.
It’s also not very filling