The expert behind Married at First Sight shares the one dating mistake we all make.

Tonight, season four of Married at First Sight will premiere at 7:30 pm on Channel 9.

In preparation for the biggest and most controversial season yet, Mamamia spoke to one of the resident experts, Dr Trisha Stratford.

Stratford is a a clinical neuropsychotherapist, which means she studies the chemicals associated with love, and what makes two potential partners biologically compatible.

Here are some fascinating hints about tonight’s episode of Married at First Sight. Post continues below…

The process of matching couples (in this season there will be 10 – more than ever before) they have each participant wear a t-shirt overnight, with no deodorant or fragrances to deter from their natural scent.

They then store the t-shirts in air tight bags, and have each person perform a “sniff test”, whereby they report whether or not they find the scent attractive.

Dr Stratford explains that a woman can detect a mans pheromones from more than three metres away, and it’s an unconscious biological process designed to assess the immune system of a potential mate.

We want an immune system that is different and complementary to ours, so we can produce strong offspring.

But not everyone can perform a laboratory standard sniff-test on every dude/chick they’re dating. So we asked Dr Stratford: what’s the biggest mistake we’re all making when it comes to dating?

Her response was simple. Never ignore your gut.

"Well what I would give as a tip is listen to your gut. And if your gut says 'not the right person', move on," she said.

If something doesn't feel right, she says "stop it there, because you're wasting your time and their time."

"It's that lovely line," she added. "Don't waste five seconds with someone you're not going to spend 15 minutes with."

It could be that - unconsciously - your pheromones aren't all that compatible.

Often, we over invest because we so desperately want it to be right. We might reason that they have a lot to offer, and, as the cliche goes, "they look good on paper".

But what you want, Dr Stratford says, is "always the butterflies in the stomach stuff."

She advises you "keep yourself open to love, knowing that it's going to come."

There was one other thing we were dying to ask Dr Stratford. Is love at first sight really possible?

Her response was simple; "absolutely".

"A lot of people are saying that they met their partners and it was love at first sight," she said.

Once we feel that overwhelming connection with a person, we then "... make a choice whether to stay with them and that's when it turns into profound love."

Tonight, we will meet all the singles, and watch two couples marry.

Laura Brodnik and Tiffany Dunk discuss all the TV on this weeks episode of The Binge. You can listen to the full episode, here. 

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