For most people, a water-based lube is still the best personal lubricant, but the details on the label now matter more than the base. This update adds what our original advice left out: osmolality (how much a lube pulls water out of tissue), why many people are moving away from glycerin, and where oils do and don't belong. The toy compatibility rules are the same as before.
If you want the fundamentals first, our original lube guide still covers the difference between water, silicone and oil bases. This post builds on it.
Water-based vs silicone lube with toys
Our long-standing advice holds: use water-based lube with silicone toys. Silicone lube can react with the surface of some silicone toys, leaving them tacky or pitted, and the damage doesn't wash off. Softer, lower-grade silicone is most at risk. Some well-made toys tolerate it, but if you want to try a silicone lube with a silicone toy, test a small dab on the base first and check it the next day.
Silicone lube is still a great choice elsewhere. It lasts longer than water-based, works in the shower, and is fine with glass, stainless steel and ABS plastic toys. Doctors writing in the British Columbia Medical Journal suggest that anyone using silicone sex aids keep a water-based lube on hand for exactly this reason.
What osmolality in lube means
Osmolality is a measure of how concentrated a liquid is. Your body's own fluids sit in a fairly narrow range. A lube that is far more concentrated, called hyperosmolar, draws water out of the cells it touches as it tries to even things out.
That matters because the lining of the vagina and rectum is thin. Lab research has shown that hyperosmolar lubes can damage these tissues. A 2012 study in PLOS One that tested over-the-counter lubricants found the hyperosmolar products reduced tissue viability and caused the surface layer of cells to slough off, while the iso-osmolar and silicone-based products tested were the gentlest. Earlier research found a similar effect on rectal tissue.
A 2012 advisory note from the World Health Organization, UNFPA and FHI 360 on lubricants for condom use flagged osmolality as a safety factor. WHO's later technical specification for personal lubricants requires osmolality below 1,200 mOsm/kg.
What to look for: products that describe themselves as iso-osmotic, body-balanced or low-osmolality, ideally with a number published. If a brand won't say, that's worth noting.
Why many people now skip glycerin
Glycerin has long been a common ingredient in water-based lube. It adds body, keeps the lube slick for longer, and gives it a faintly sweet taste. It is also one of the main ingredients that pushes osmolality up, along with glycols such as propylene glycol.
Some clinicians now recommend avoiding lubes with glycerin, propylene glycol, fragrance and flavorings, particularly for people who get irritation or recurring infections. If you or your partner notice itching, burning or more infections after using a particular lube, switching to a glycerin-free formula is an easy first step. Many of those use cellulose-based thickeners to get a long-lasting glide without the glycerin.
Where oil-based lube fits
Coconut oil and other oil-based products are popular for massage and hand play. They're thick, they don't dry out quickly, and they feel good on skin.
The catch is latex. The CDC's condom guidance says not to use oil-based products like baby oil, lotion or petroleum jelly with condoms, because they can cause the condom to break. Oil is also hard to wash off toys and out of sheets. Keep oils for external massage, away from latex condoms and away from your toys.
How to pick the best personal lubricant for toys and sex
- Start with a water-based lube for anything silicone, including strokers and couples vibrators.
- Check the ingredient list and pass on glycerin, propylene glycol, fragrance and flavor if either of you is sensitive.
- Look for a brand that publishes its osmolality or calls its formula iso-osmotic.
- Keep a silicone lube for the shower and for glass, steel and ABS toys.
- Use a generous amount and reapply. Friction from too little lube causes more trouble than most formulas.
Dryness that changes with age or hormones is its own topic, and we cover it for couples in sex after 40. This is general information, not medical advice. If you have pain, bleeding, or irritation that keeps coming back, see a doctor.
You can find water-based, silicone and glycerin-free options in our lube and care collection. Read the back of the bottle before you buy, and keep one water-based bottle next to your silicone toys.