Sexual chemistry is electrifying, and you know it when you feel it. The overwhelming desire to be with someone, the butterflies, the nerves, the excitement! It's magical and intoxicating, and it's often completely unexplainable. Science goes some way to clarifying the practical side of things in sexual relationships, but exactly why it strikes remains one of life's greatest (and most thrilling) mysteries.
Everyone experiences sexual chemistry differently but, broadly speaking, it's a very strong but ineffable feeling, an almost euphoric feeling, in your body drawing you to another person.
Usually, this attraction is physical, although it can also be intellectual or emotional.
There are some unmistakable behaviors, such as stomach flutters, giddiness, dilated pupils, an increased heart rate, blushing or sweatiness, glowing facial expressions, as well as the symptoms you experience when you feel sexual desire, such as increased vaginal lubrication or an erection.
Mentally, you might find it hard to eat, sleep or concentrate because you're so excited about this connection. And because you are brimming with positive feelings and experiencing a huge sense of longing to be near this person. This is usually the physical chemistry talking!
It often hits like a lightening bolt, but sexual chemistry isn't always immediate. For many couples, it's built up over time.
This kind of sexual attraction comes down to a combination of factors.
From a biological perspective, some researchers believe sexual chemistry occurs as a physical response to another person's pheromones (the sex hormones we humans emit through our skin and sweat). When your physiology identifies a match - bingo!
Neuroscientists have also found that when we have a romantic attraction to someone, our brains release high levels of dopamine and norepinephrine, which gives us that energetic, giddy feeling. In fact, sexual chemistry disrupts your frontal lobe system so much it's like your brain is on drugs for a period of time (which is why heartbreak or rejection can hurt so much, because it's akin to drug withdrawal).
Then there are social factors. We might be attracted to someone because they fit the mould of what we've been taught is attractive by our various cultures and communities. Or the person in question might remind us of an earlier pleasurable experience.
As many romantic partners will tell you, however, you can never know when sexual chemistry is going to strike.
Apart from the fact that sexual chemistry is absolutely thrilling, it quite often leads to sex, which itself has lots of physical benefits including improved immune function and positive cardiac effects. Studies also show that having sex as a result of experiencing sexual chemistry provides relief from stress, and promotes higher rates of happiness and sleep quality.
Sexual chemistry can also result in new romantic relationships, and contribute to a deeper connection in existing ones.
However, there are some downsides of explosive sexual chemistry. Sometimes, this connection is based solely on physical attraction, and doesn't necessarily spell success for a lasting relationship or meaningful emotional connection. If you've ever seen a friend fall head over heels for someone you know is completely unsuitable for them, that'll be sexual chemistry at work.
It can also muddle communication between those involved. If one person is pursing the chemistry for sexual gratification alone, this can be upsetting to a person who might be seeking a long term, loving relationship.
Potent sexual chemistry is not sustainable forever. Eventually hormones will settle down and a couple will either decide to part ways, or will continue onwards together thriving on the intimacy, trust, love and sexual compatibility that remains. This doesn't mean you stop having sex, of course, but rather that the heady breathlessness of your early encounters has evolved into a deeper, calmer and more emotionally fulfilling rhythm.
Sexual attraction isn't always linear, however. It can ebb and flow throughout long-term relationships for many reasons. Life events such as moving house, a stressful job or parenting can put a dampener on things temporarily, only for those feelings to come rushing back once the stressors have been removed.
Equally, sexual chemistry doesn't always hit like a bolt of lightning. Consider the couples who were friends for years before starting to date and have sex. The sexual chemistry there wasn't instant, but instead built over time from a growing sense of romantic attraction.
The short answer is 'no'. People's individual needs and desires within relationships are wholly unique, and there are many people for whom sex and sexual attraction are not key ingredients. As long as you and your partner are on the same page about what makes your relationship fulfilling, whether that's trust, companionship, romantic attraction or shared values, then sex absolutely does not have to feature in your partnership.
For others, sex and sexual chemistry are a vital part of a relationship, which is equally valid.
However, couples that are experiencing difficulties in their relationship might put undue emphasis on sexual chemistry, which can become disruptive. In these instances, it's helpful to consider whether the problems are explicitly linked to your sex life, or if there are deeper underlying issues outside of the bedroom.
You can't force sexual chemistry with someone you're not attracted to, but you can cultivate an existing feeling of attraction to keep sexual chemistry alive. Communicate openly with one another, share your emotions and spend time together trying new things, whether that's a new hobby or sharing sexy fantasies. Just because the chemistry isn't there right now, doesn't mean it won't come back.