Discipline?

Twice a day, I drink green tea
Swallow a multivitamin each day
In the hope that I’ll stay healthy
But really, who’s to say.

I wake up each morning
Go for a run, assume strange stances
In the hope that I’ll stay in shape
Seriously, what are the chances.

I try and watch what I eat
Avoid butter, have dinner before nine
But all my goodness goes for a toss
When I open a bottle of wine.

Surely you can’t fault me
It’s a tough life, we all need our vices
While my waistline may take a hit
I hope my wit suffices.