We've all heard the "everything in moderation" rule, and it seems like such a common sense way to approach your diet. Allowing yourself small portions of all sorts of foods, including treats like ice cream and bacon, lets you enjoy yourself while still saving calories, right?

Not necessarily, says a new study published in the journal PLOS ONE. For the study, researchers recruited more than 5,000 adult men and women, and then followed them over a period of 5-7 years, periodically surveying them about their diets. They also tracked how their waist circumferences (which measures belly fat) and overall weights changed over time.

In the end, they found that people who tended to eat a little bit of everything were much more likely to gain belly fat over time. In fact, among the people with the most diet diversity, waist circumference grew 120% by the end of the study.

RELATED: Best Superfoods for Weight Loss

They also found that those who consumed a broader spectrum of foods tended to eat more unhealthy ones, like processed meats, desserts, and soda, rather than fruits and veggies.

So should you stop enjoying a wider variety of small indulges and just really go for it with fewer, healthier foods? Maybe, but there’s a little more to it than that. Here are my five tips for making moderation work for both your taste buds and your waistline.

Rank potential splurges

Any time you're faced with a treat use a scale from 1 to 5 to rank it, with 1 being “meh” and 5 being “can’t-live-without.” If something doesn’t score at least a 4, skip it. I bet you won’t regret passing up these foods in the moment, and you especially won't be missing them the next day when you're stepping into your jeans. This simple strategy can help you cut back on foods that add extra calories, but aren’t satisfying enough to prevent you from still reaching for something else.

Budget your shopping trips

Rather than budgeting financially I’m referring to limiting the number of splurge-y foods you bring home at one time. A 2013 study from the journal Appetite, found that more often you eat a food without mixing things up, the less exciting it becomes— kind of a “been there, done that” phenomenon.

In fact, even small variations can stimulate your senses in new ways, which can prompt you to eat more. So if you bring several different treats home from the supermarket at once (a pint of ice cream, chips, cookies, and candy) you’re likely to sample a little of each, which can add up to downing far more calories than if you had fewer options available. Test this trick out for yourself to see if it impacts your overall intake.

RELATED: 13 Best (and Worst) Ways to Measure Body Fat

Make room for splurges

To create balance and reduce the number of total foods you eat, omit some things to build in others. For example, if you want fries, order your turkey burger wrapped in lettuce instead of a bun. Or if you’re craving a cookie, have stir fried veggies and protein without the rice, or a salad topped with lean protein in place of a wrap. Most of my clients’ favorite indulgences are high in carbs, so omitting other carb-rich foods within the same meal just makes sense.

Go for quality first

Make it a rule to only treat yourself after consuming quality calories first, like splitting a dessert after lunching on lean protein and a generous portion of veggies. Or take it a step further and make nutrient-rich foods your treats, like a few squares of 70% dark chocolate, or a sliced apple dipped in almond butter.

Even if you're tracking your food intake religiously and making room for your treats with the smart swaps, focusing on quality is still key. For example, a University of Florida study found that people who ate more whole plant-based foods had smaller waist measurements, and lower body fat percentages than those who had low intakes, even though they consumed about the same number of daily calories.

RELATED: 7 Foods That Fight Fat

Track yourself, even briefly

Most people underestimate how much they eat, sometimes significantly.

In a Cornell University study researchers used a hidden camera to spy on people at an Italian restaurant. Just five minutes after the meal they asked diners how much bread they had consumed. Most people ate about 30% more than they thought, and 12% who were seen eating bread on camera denied having any at all.

If you tend to mindlessly munch, like many people do, one of the only ways to get a handle on your intake is to track it. You can use good old-fashioned pen and paper, an app on your smartphone, or a website. If that's too time consuming I ask some of my clients to simply snap a photo of everything they eat and drink and text them to me. Within a day or two they’re often shocked by how much more they eat, or how many more foods they eat, than they realized. But once they're aware of it, they learn to cut back.

Just a few days of tracking can raise your awareness significantly, and allow to catch yourself before you follow through with nibbling on autopilot.

What’s your take on this topic? Chat with us on Twitter by mentioning @goodhealth and @CynthiaSass.

Cynthia Sass is a nutritionist and registered dietitian with master’s degrees in both nutrition science and public health. Frequently seen on national TV, she’s Health’s contributing nutrition editor, and privately counsels clients in New York, Los Angeles, and long distance. Cynthia is currently the sports nutrition consultant to the New York Yankees, previously worked with three other professional sports teams, and is board certified as a specialist in sports dietetics. Cynthia is a three-time New York Times best-selling author, and her brand new book is Slim Down Now: Shed Pounds and Inches with Real Food, Real Fast. Connect with her on Facebook, Twitter and Pinterest.