Osmolality is something not many manufacturers talk about or feature on their products. This could be because they would rather say "low irritation" because more consumers will know what that means. The other more concerning reason is that their lubricant does not have the recommended level of osmolality that body safe products should strive for.
What on earth am I talking about
In simple terms, osmolality refers to how concentrated the particles in a water-based lubricant is. This is important as lubricants that are too concentrated can affect the body's natural epithelial skin. Our skin and especially genital tissue are always trying to maintain an equilibrium of osmolality (some very vague memories of high school science might be coming back right about now). If the cells in our epithelial skin break, we may possibly feel skin irritation, become prone to infection and may even affect fertility. In other words, it's important to know about!
We're getting a bit more technical now. When your body comes into contact with a water-based lubricant, cells undergo osmosis. Osmosis refers to water leaving bodily cells in the hopes of maintaining an equilibrium between particles within the cell and the fluid surrounding it. If the concentration of the incoming liquid is higher than that of the cell, this causes osmotic pressure. The higher the amount of concentration, the more water your cells will release in an attempt to dilute the lubricant. However, if too much water is released, the cell itself becomes too concentrated, causing the cell to die and eventually the network of surrounding cells as well. This is why high concentration lubricants can potentially be detrimental to your safety.
So, water-based lubes can be categorised into one of three levels of concentration. An easy way to think about it, imagine any juice cordial you like. The more cordial you put into your favourite drink, the more concentrated it becomes.
Hypotonic refers to solutions that has a lot of water content, diluted! A dilute solution means that a lot of water is going to be entering and leaving cells. This is awesome for anyone experiencing vaginal dryness as it will reinvigorate the tissue and encourage natural lubrication. What we can further learn from hypotonic solutions is why sex in the shower can be dangerous. Water is not a lubricant and will actually dry your skin! This is because too much water entering cells in your delicate areas will cause them to break, resulting in dryness.
Solutions that are perfectly in the middle, they boast a very similar concentration solution to the ones found in our cells. Therefore, equal amounts of water cycles in and out of the cell, reducing friction, nobody gets hurt and everyone's happy. An isotonic lubricant would otherwise be known as having low osmolality and is the recommended pick by sexual health specialists.
High concentration solutions! The concentration of the incoming solution is greater than the cell. These liquids are likely to cause too much water to leave the cell, causing it to be damaged or die. You can see how any hypertonic lubricants can increase the risk of skin irritation and yeast infection.
As mentioned at the start of this article, one problem is that many manufacturers don't volunteer this information about their products. They will say that lubricant will positively reduce friction and keep your sex life safe, but will not specifically say if something is low osmolality. Therefore, things become confusing when popular well reviewed products are seemingly safe and pleasure enabling, yet mention little about why they are recommended.
Let's take our most popular water based lubricant Wet Stuff Gold for example. Every review is positive, yet there is no suggestion about having a low osmolality. It could be isotonic, yet it's still possible that this lube doesn't meet recommended osmolality levels. The body can still handle higher concentrated solutions and everyone's body will be different in how well it copes. If you feel any discomfort during or after using any type of lube, an overly concentrated lube might be to blame.
What can give you a good indication of low osmolality lubricants?
When reading product descriptions or doing further research on a lubricant, one thing you want to look for is glycol content. Basically, glycerine or propylene glycol-based lubes generally are hypertonic (high concentration).
Here's a few low osmolality water-based lubes identified from SMARTSEXLUBE's reviewed list.
JimmyJane - Feel Sexy
This lube actually claims low osmolality! Brilliant, props to JimmyJane. Notice how the description says "free of glycerin, parabens, and propylene glycol."
"Protects mucus membranes, and if necessary, supports healing." The information provided for this lubricant is exemplary.
Sir Richards - Slick Dicks
Better than spit apparently... and also better than a lot of other lubricants.
Blossom Organics Arousal Gel
100% free of harsh ingredients and expertly formulated by a woman.