Eating healthy is only half the battle.

Perhaps you’ve swapped your pancake and sausage breakfast for avocado toast, gone cold turkey on M&Ms, and even added salad to your meal repertoire.

But if you haven’t started paying attention to what you’re drinking, you may not have really made a dent.

Sweetened beverages like soda and juice can make up a surprising portion of the calories you consume each day, yet they don’t fill you up the same way solid food does.

Those are some of the reasons that Cara Anselmo, a nutritionist and outpatient dietitian at New York’s Memorial Sloan-Kettering Cancer Center, advises her clients who are trying to lose weight to stop drinking beverages with calories.

“If you drink 500 calories of liquid versus eating 500 calories of food you’re going to feel much less satiated, which is one of the reasons soda and sweetened drinks are such horrible things. You don’t get a sense of fullness,” Anselmo tells Business Insider.

Researchers from Harvard University and Children’s Hospital in Boston tested this idea in an 8-year study that included nearly 50,000 women.

When compared to participants who slashed their intake of sweetened drinks like soda or fruit punch, those who started drinking more sugary beverages gained weight and increased their risk of developing type 2 diabetes. The more their sweet drink intake increased, the more weight they gained and the more their disease risk went up.

This is partially because the calories we get from sugary beverages don’t fill us up, as several short-term studies exploring people’s appetite and eating behaviour after drinking sweetened beverages have suggested. In fact, they may do the opposite.

“When drinking fluid calories, people often end up eating more calories overall,” Richard Mattes, a professor of nutrition at Purdue University tells Live Science.

The key takeaway: If you’re trying to lose weight, you can start by reducing your intake of sugary drinks like juice, soda, and fruit punch. Instead, wash down your meals with water.

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