Experts say drinking a lot of sweetened beverages can lead to obesity, diabetes, and heart disease.

This week, the federal government reversed decades of policy and allowed states to ban the use of food stamps to buy soda and other sweetened drinks.

In addition, a handful of cities have put taxes on them over the strong objections of the beverage industry.

To find out more, we went to opposite coasts.

At a corner shop in Philadelphia, steps from the Liberty Bell, a 20-ounce bottle of Coca-Cola

cost $3.9.

But just a few miles south, beyond the city limits, a PBS news producer found a price of

279, 30 cents cheaper. Why the difference? Since 2017, Philadelphia has taxed sugar, sweetened

drinks at a rate of one and a half cents an ounce. The city council imposed the

levy as a public health measure. I did not think a sweetened beverage tax was going to actually

impact health. Why not? Well, it's just very, very difficult to influence weight. Our bodies

are biologically designed to actually help us keep weight on once we gain it.

Christina Roberto and researchers at the University of Pennsylvania track the effects of the tax.

Some of what they found surprised them.

The overall effect of the tax in Philly was a 35% reduction in sales of these tax strings.

Now I've been working in this area for about 20 years,

and I have never seen a behavioral effect that large, right?

Like, eating behavior is so hard to change,

let alone change it over the long term.

And so to me, I just felt like, oh my gosh,

this is an incredible intervention to

actually get people to, you know, stop or consume fewer of these drinks that we know are making

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