26-year-old Lena Lupari is from Ireland and she's going blind.

I feel bad because it was totally avoidable!

The reason Lena is losing her vision is that she spent the past several years drinking 28 cans of Red Bull a DAY.  28 per freaking day!  That's 3,000 calories!

She gained a lot of weight, and ballooned up to over 360 pounds which made her develop a rare condition where her brain swelled up and stopped her optic nerve from working.

It's called idiopathic intracranial hypertension.

Don't worry, doctors say she can start to reverse the process but she'll need to lose at least 30% of her weight and have surgery to keep her eyesight.

But, the good news is, she has stopped drinking all that Red Bull.

And, in case you were wondering, she was spending up to $10,000 a year on her habit!  That's so nuts!

Click here to see a picture of Lena.

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