The question regularly comes up on warming silicone toys and if it’s even safe, for the toys or for oneself. Unlike other materials like PVC, Vinyl, TPR, and TPE that can’t withstand higher temperatures without beginning to outgas chemicals or even melt, silicone is unaffected by heat at these lower temps and is perfect for warming up toys before play.
As you guessed, there is no research on the topic, only the community collective wisdom passed down over time.
So why do people do it? Warming can offer a more lifelike play experience, and help the body to relax the sphincters. It also adds a little variety in play by producing different sensations. In much the same way chilling a toy is also practiced, but not as widely. A cooler toy often helps people feel better where it is inside and perhaps help in self discovery in where the toy is.
Water Bath – The easiest and safest way is to simply bathe them in a sink of water the temperature you want them to be. It’s important to not overheat them because you can actually scald your tender colon if they are hot enough. How hot is too much? You can think about how hot foods have to be in your mouth before they hurt, but then consider too there is constant contact between the toy and your colon and no chance of it cooling down. Holding a warmed toy against the inside of your wrist for 30 seconds is a good indicator too of what is too much. You must err on the side of caution here, pain receptors are absent in the colon except for pressure, so you won’t feel the heat the same way as you do on your skin.
Heating Pad – An old playroom trick. Keeping a low bench with a heating pad on it in your play area is a tried and true method for warming toys for play. Simply lay the toys out you want to play with, throw a towel over them and plug the pad in. You’ll find the correct setting that will warm them and not make them too hot. This method is great for extend play sessions when you might not use a toy for an hour or so. Just watch out for any hot spots.
Microwave – This can be done, but caution needs to be exercised when warming silicone in the microwave. The danger being that the core can heat up beyond what you feel on the surface and then not exit until it’s buried deep inside you, causing a harmful rise in temperature. This method is best used in a pinch for a single toy to simply “take the chill off” rather than the goal of heating it.