New Year’s gets all the buzz when it comes to making healthy-eating resolutions, but summer is the perfect time to revamp your diet.

Fresh produce is at its peak, lean proteins are beckoning to be grilled, and you’ve got plenty of incentive to show off your results in a sexy swimsuit or shorts. But it’s not just about how good your abs look in a bikini. This is a great time to regain a smarter relationship with food. One way to do this is by using the wildly popular Whole30 program, which has helped hundreds of thousands of people reset their diets by focusing on clean foods and eliminating sugar, grains, alcohol, dairy, and more. The premise: These foods have the potential to cause digestive, metabolic, and inflammatory disorders that can compromise your health.

“The only way to know what foods might be causing problems is by pushing them off your plate for 30 days,” says Melissa Hartwig, the co-creator of the Whole30 program. Even if you don’t have any food sensitivities, it’s still an opportunity to get the junk out of your diet while crushing your cravings for sugar and processed carbs, and adding in more fruits, vegetables, healthy fats, meat, and seafood.

It’s also perfect for active women who want to fuel up for performance. “Your blood-sugar levels will be better regulated, so you won’t have those highs and lows,” says Hartwig. Plus, without inflammation-causing sugar and processed carbs, you can recover faster post-workout. Try the Whole30 diet for one month, then follow the guidelines for adding foods back to your diet. You’ll soon feel lighter, stronger, and ready to take on all that the season has to offer.

The rules

The Whole30 isn’t meant to be done halfway. “You have to go all in to see the full benefits the program has to offer,” says Hartwig. “Doing something in moderation can actually be harder because it’s not as concrete. It’s easier on your brain and willpower to just say ‘no.’” Plus, if you don’t eliminate everything that could potentially be causing problems, you may never be able to hone in on your specific needs. So, no exceptions—follow these rules for just 30 days.

Rule 1

No added sugars of any kind.
Eliminate real sugars (cane, brown sugar, maple syrup, honey, agave, coconut sugar) and the manufactured kind (Splenda, Equal, NutraSweet, xylitol, stevia, etc.). Be sure to read labels, since sugar can sneak into a wide variety of foods (spaghetti sauce, salad dressing, marinades, etc.).

Rule 2

No alcohol. Not for sipping nor cooking.

Rule 3

No grains or pseudo grains.
Cut out all forms, even if they don’t contain gluten. Think: wheat, rye, barley, oats, corn, rice, millet, bulgur, sorghum, sprouted grains, amaranth, buckwheat, and quinoa, as well as forms of these foods, like bran, germ, and starch. Reading labels here is again key.

Rule 4

No legumes. Beans (black, red, pinto, navy, white, kidney, etc.); peas, soy (tofu, edamame, soy sauce, miso); chickpeas, lentils, and peanuts (including peanut butter) are gone. Also be on the lookout for soybean oil, soy lecithin, and other soy products that sneak into foods and vitamins.

Rule 5

No dairy. Eliminate cow’s milk, sheep’s milk, cheese, kefir, and yogurt. Only clarified butter (which is simmered down at a low temperature to separate milk solids from pure butter oil) and ghee (butter that is simmered even longer, until the milk proteins begin to brown and clump; or purchase premade ghee) are OK.

Rule 6

No carrageenan (a concentrated, processed seafood weed extract used to thicken foods), MSG, or added sulfites. Be on the lookout for these pro-inflammatory additives on nutrition labels.

Rule 7

No re-creating junk food. We love protein pancakes as much as the next person, but, for the next 30 days, these and other healthier remakes of comfort foods like Paleo zucchini bread are off-limits. “This program is about changing your emotional relationship to food. It doesn’t matter if those muffins or brownies are gluten-free. We want you to find other ways to self-soothe and find comfort that won’t have you falling into the same bad habits,” says Hartwig.

Rule 8

No scales. Don’t weigh yourself, analyze your body fat, or take any other measurements for the next 30 days. “People get so enamored with numbers, but they really tell you nothing about your health, habits, or relationship with food,” says Hartwig. This plan is about far more than weight loss, she adds. “Remove measurements from the equation, and you can focus on how you really feel.”

The exceptions

As with every rule, there are a few exceptions, including the ones below. Feel free to add these foods into your Whole30 plan.

Clarified butter or ghee: Neither contain milk proteins, so these are both on the OK list.

Fruit juice as a sweetener: Use orange, apple, and other fruit juice in moderation.

Green beans, snow peas, sugar snap peas: These are technically legumes, but there’s enough good stuff in them to keep them on the list.

Vinegar: Avoid flavored vinegars with added sugars and malt vinegar, but white, balsamic, apple cider, red wine, white wine, and rice vinegar are OK.

What comes next?

You’ve stuck to the rules for the past 30 days, so what happens on Day 31? While it’s tempting to indulge in everything you’ve missed, it’s important to take it slow. “This is your chance to reintroduce foods, and to carefully evaluate how they make you feel,” says Hartwig. If something once beloved doesn’t make you feel well during this phase, try to avoid it going forward. If you’re anxious to get back to “normal,” try the “Fast Track” program; or slowly reintroduce the groups you’ve cut out, one at a time, over a longer period.

Day 1

Add in: Gluten-free alcohol (Note: If you’re not a drinker, go directly to Day 4)

How to: Enjoy a cocktail made with vodka, gin, rum, or tequila, or have some wine or gluten-free beer. Return to the Whole30 for the next two to three days and see how you feel.

Day 4

Add in: Legumes

How to: Anything in the beans and legumes group is now fair game, from peanut butter on an apple to a gluten-free veggie burger. Again, go back to the Whole30 for the next two to three days and evaluate how you feel.

Day 7

Add in: Non-gluten grains

How to: Now’s the time to try rice (white and/or brown), corn, oats, quinoa, and other grains labeled gluten-free. Keep the rest of your diet in line with Whole30. See how you feel, then go back to a stricter Whole30 for the next two days.

Day 10

Add in: Dairy

How to: Bring back your yogurt, your coffee with creamer, salad with shredded cheese. You can even use butter on your baked potato or with your eggs. Evaluate how you feel, then go back to the Whole30 for the next two days.

Day 13

Add in: Grains with gluten

How to: Say hello to whole-grain bread, wheat crackers, pasta, even beer, and see how your body reacts. Return to the Whole30 plan for the next two days.

Day 14

Add in: Your choice

How to: Now that you’ve gone through the full cycle to identify the most common food sensitivities, you’re able to bring back most of the food sources you’ve eliminated over the past month. Just be careful about overdoing it, especially when it comes to sugar. Hopefully your sugar addiction has been tamed, and you may not even miss it. While the occasional indulgence is OK, try not to get swept away into the high-sugar habit.

For more on the challenge, check out Whole30.com and the Whole30 series of books by Melissa and Dallas Hartwig.