These before-and-after photos show why the future of Weight Watchers is uncertain

Instagram/21 Day Fix

What's next for Weight Watchers?

The future looks uncertain for an old-school brand facing a new wave of competition from free or less expensive diet plans popular on Instagram and Pinterest. 

Weight Watchers' typical membership would cost about $460 per year, while the new competitors are free or a fraction of the price. 

The brand's shares fell Thursday after the company's outlook for growth failed to meet Wall Street's expectations. 

We broke down the main competition that's challenging Weight Watchers' future as Instagram continues to change how people diet and share results. 

There's the 21 Day Fix.

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The 21 Day Fix is coupled with a workout program.

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The workouts include pilates, yoga, cardio, and upper and body strength training. People who order the workout DVDs through Beachbody get a seventh bonus workout.

The workouts are led by trainer Autumn Calabrese.

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