Whether you grew up eating classic PB&J sandwiches or mac and cheese, you probably remember exactly where your parents kept the peanut butter jar. Now, this spread is a protein-packed favorite for many, but is peanut butter keto or is it off-limits to people who follow this lifestyle?

First, a quick recap: The keto diet emphasizes filling your plate with more fats and fewer carbs. After two to seven days, you go into a state called ketosis, where your body realizes it doesn't have enough carbs to use for energy and burns fat instead to keep it running.

Everyone's needs are different. But as a general rule of thumb, the keto diet recommends getting 60 to 75 percent of your calories from fat, 15 to 30 percent from protein, and five to 10 percent from carbs. This translates to eating a maximum of 50 grams of carbs per day. Some strict keto fans stick to just 20 grams a day.

Nuts, like peanuts, can absolutely play a role in the keto diet, says Jessica Harvey, RD, a clinical educator at Keto-Mojo. "The thing about nuts is that they contain a lot of calories," she says. "So if your goal for doing keto or low carb is to lose weight, you just need to be very mindful about your portion sizes."

This is a breakdown of regular peanut butter's nutritional value, according to the USDA.

Serving size: 32 grams (two tablespoons)

Natural peanut butter, on the other hand, looks more like this.

Serving size: 32 grams (two tablespoons)

So, yep, peanut butter is keto—in small amounts. It's a great source of fat, fiber, and protein, says Priscilla Blevins, RD, the owner of Keto Girl Nutritionist.

One note, though: The calories and carbs can add up quickly, so it's best to stick with one serving or less per day, Harvey notes.

"It's always best to stick to peanut butters that are organic or really from the source," says Blevins, which means no added sugars. You'll also want to steer clear of products that contain fillers, like palm oil or other kinds of hydrogenated oil, which are usually added to preserve freshness, per Harvey.

Getting freshly ground peanut butter from your local grocery or health food store is the best way to go, since it's usually made with just the nuts and maybe a little salt. "That is amazing because then it's extra nutritious," explains Blevins.

If you can't find that, Justin's Classic Peanut Butter is also a great and convenient option you can buy. It only contains six grams of carbs per serving and no added sugar. It's also available in individual packets for an easy keto snack on the go.

Common brands like Jif and Skippy ballpark at around a similar number for carbs (eight grams and six grams, respectively), but both products have added sugars. You can definitely still have some while on keto, but opting for naturally sweetened versions is still your best bet.

There's no shame in eating it straight out of the jar. You can also incorporate it into your favorite meals and snacks. For a high-protein breakfast, Harvey recommends mixing peanut butter into your favorite low-carb yogurt.

Pairing veggies with peanut butter is also a win-win. Celery is a great choice, but you can pick any low-carb option you like. Harvey suggests dipping apple slices into this creamy spread too—just watch your portions.

Plenty of other nut butters are keto-friendly too, such as macadamia nut, almond butter, cashew, and sunflower butter. Many even come in crunchy varieties (just make sure to stick with natural brands and pay attention to how much of it you're eating).

Here's a quick breakdown of each type, according to the USDA.

Macadamia nut butter. Serving size: 32 grams (two tablespoons), 195 calories, four grams of carbs, and two grams of net carbs

Almond butter. Serving size: 50 grams (roughly three tablespoons), 322 calories, 10.5 grams of carbs, and six grams of net carbs

Cashew butter. Serving size: 32 grams (two tablespoons), 194 calories, 9.5 grams of carbs, and eight grams of net carbs

Sunflower seed butter. Serving size: 32 grams (two tablespoons), 197 calories, 7.5 grams of carbs, and 5.5 grams of net carbs

As with any other foods, remember to enjoy it in moderation. While you need to watch your carbs on the keto diet, know that you can still eat the peanut butter you love.

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