Lube formulas have gotten, oh, let’s say, “creative” in recent years. It’s 2019 and you can now slather your nether regions with CBD, but there are still a few ingredients you should never (repeat: never) allow near your bits. Lauren Steinberg, founder of feminine wellness brand Queen V, says you should comb through the contents of the lube label the same way you would with your beauty products or your food.

“I always recommend taking a quick look at the back of a bottle before using it,” says Steinberg. “There are certain ingredients that aren’t super vagina-friendly, ingredients that don’t match the pH level of your vagina and shouldn’t go inside your body.” Specifically, glycol (which is used as a base for anti-freeze), glycerin (which has been linked to yeast infections), and fragrances (an umbrella term for carcinogens, reproductive toxins, and allergens) don’t belong within a mile of your vagina.

In addition, the World Health Organization (WHO) recommends only using lubricants with a pH of 4.5 and an osmolality—that is, electrolyte-water balance—below 1200 mOsm/kg. (You can find a list of common lubes and their pH and osmolality levels here.) And remember: oil-based lubes can cause latex condom breakage—so look for water- or silicone-based formulas instead.

For her part, Steinberg says she always seeks out one ingredient in a bottle. “I highly recommend looking for an aloe-based lubricant. Aloe is super hydrating,” she says. Queen V’s P.S. I Lube You ($9) fits the bill, as well as Sustain Natural Organic Lubricant ($20 for a pack of two) and LOLA personal lubricant ($14). But if you’re in the mood and in a pinch, Aimee Eyvazzadeh, MD, a board-certified OB-GYN and reproductive endocrinologist, previously told Well+Good that you can DIY with ingredients from your pantry, or some good old saliva. “Natural products really are the best,” she said. “For my fertility patients, I recommend using either egg whites, olive oil, or coconut oil. You likely have many of these at home and know they’re not toxic.”

Even when you’re being dirty, let’s keep the ingredients clean, folks.

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