Has anyone ever used the Acai Berry supplements to lose weight or heard of any bad side effects?

It doesn’t work save your money.

The short answer is no, it’s an expensive advertising campaign funded by the poorpeople that fall for the lies.
The loss is to your bank balance.
Many have reported on here that they are useless.
Type in acai and scam.
açai juice has only middling levels of antioxidants—less than that of Concord grape, blueberry, and black cherry juices. antioxidants do not aid weight loss.
Oprah Winfrey, Mehmet Oz, and Rachael Ray have all publicly disassociated themselves from the açai sites that make unauthorized use their names.
There are no magical berries from the Brazilian rainforest that cure obesity. Claims are unproven, evidence is anecdotal, antioxidants are beneficial, but do not aid weight loss.

"These diet ‘bloggers’ are just a mirage," Schardt said. "Their weight loss is courtesy of Photoshop, not açai."

The colon is self cleansing. All the cleanser does is give you diarrhoea – water weight lost.
Colon cleansing can cause vomiting, nausea and abdominal cramps. It can cause a dangerous loss of water and electrolytes, which can lead to dehydration and even abnormal heart rhythms

Its a scam, you’d be better off drinking green tea a couple of times a day.

It sure sounds like a GREAT food to add to one’s diet to help with weight loss.
But it seems expensive.
I haven’t tried it myself, and I hear it’s not so easy to get ahold of.

But either way, your better off with good ole jumping jacks, crunches, running and some healthy meals.