If you search for diet coffee online, you’ll see two things: people selling it and people calling it a scam. But does this popular beverage really have potential to help you lose weight?

The key may be in how you prepare your coffee. For best results, stick to plain black coffee without milk, sugar or flavored additives. That way, you’ll get all the benefits of coffee — including its ability to increase fat-burning and boost energy levels — without all the extra calories.

Java Slim: A Comprehensive Guide to Weight Loss Coffee Benefits

In a recent study, researchers found that people who drank coffee had lower weight gains than those who didn’t. This was true even when controlling for many factors, such as age, exercise and diet. In fact, those who drank one cup of plain, unsweetened coffee per day gained only about a quarter of the expected weight gain over four years. The reason is likely because the coffee was a source of additional fiber, which helps us feel full and satisfied with our meals. It also increased a hormone called peptide YY, which signals our brains that we’re satiated.

But before you run out to stock up on all the new weight loss coffees on the market, be aware that this research is just in its early stages and doesn’t prove that coffee actually caused the decreased weight gains. Also, if you have gastrointestinal issues (such as acid reflux, heartburn, or IBS), drinking coffee can make them worse.