Celebrity couples: They are good-looking, loved up and know how to work it on the red carpet, but there’s an increasing number of A-listers getting X-rated when it comes to Public Displays of Affection.

For Justin Bieber & girlfriend Selena Gomez, a day at the beach turned into something of a love-in, but they are not alone. Many celebs have become experts in all types of public affection, so here’s a selection of my favorites:

First up and with plenty of cringe factor is The Steamy Smooch: Will Smith & wife Jada Pinkett-Smith were caught on a Jumbotron going for a Hollywood kiss at a basketball game, while J-Lo and Casper Smart have been snapped smooching anywhere and everywhere.

The Passionate Peck: Restrained and reassuring. David Beckham kissed Victoria’s nose after receiving his Order of the British Empire, while President Barack Obama seems to prefer the First Lady’s forehead.

The United Front is a favorite of Tom Cruise and Katie Holmes: They love the show of solidarity, but Brad and Angelina manage to pull it off with a few more hands.

The Grope: Justin Timberlake and Mila Kunis are offenders. Perhaps they went a bit too far at the MTV awards, thankfully it was tongue-in-cheek (they aren’t even a couple.) Brad Pitt was a little subtler at a film premiere, reaching for Angie’s derriere as they were photographed upfront.

Of course it’s not just celebrities displaying their affection for each other, so how far would you go?

You may find yourself cringing when you see your favorite celebs and their wandering hands, but new research actually shows that when we see people kiss and cuddle in public, it triggers positive emotions in the brain, leaving us with that warm and fuzzy feeling inside.

And if that’s the case, well I say, smooch away!

Hi Simone, 

I’ve heard callers on Loveline talk about their younger guys! I’m in my mid 30s and my boyfriend is seven years younger than me (lucky me!). Our sex life is great, but I’ve heard that women reach their sexual peak around my age so I’m worried that in a year or two I’m going to be past it. Is there anything I could do to prolong my peak?

Once a week, eat three cloves of garlic, mixed with horny goats weed from China… I’m sure I’ve read that somewhere. Like most other claims about prolonging your sexual peak, I haven’t seen any convincing evidence that any of them actually work. So I remain sceptical about this kind of thing and anything like it.

The idea of men and women having different peaks arose after Alfred Kinsey, the renowned sexologist, discovered that women in their 30’s had more orgasms than they did at any other time in their lives. Beneath the attention grabbing statistics, there are many factors – other than the physiological – that will have contributed to his findings. One of them is as simple as a woman feeling more confident and content as a thirty something. This may or may not be the case for you. But my point is, your sexuality is unique. It’s made up of physical, emotional and environmental factors. What’s going on for you both personally and in your relationship can change from day to day and week to week. For example, whatever your age, if you suffer some kind of loss or stress, the frequency of how often you want sex will change (and most likely be reduced). Alternatively, if you are having a good run of things, your sex drive could be as rampant as it was in your early 20s.

Of course it’s true that levels of testosterone (dubbed the desire hormone) in women drops as we age. But, testosterone alone doesn’t account for your sex drive. It’s simply one part of the mix. You could always get your levels checked, but no amount of testosterone will make you like (and want to be physically close to) your boyfriend if you’re arguing. The point is, sex isn’t about reaching a mythical peak at age 31 ¾ before everything goes downhill from there for the rest of your life.  Ask any 70 year old who enjoys their sex life (and many do, believe me). So in answer to your question: Are you on your way down or your way up on the (fictitious) chart? Who cares! The only sex rule you need to be following is the one that it sounds like you know already – enjoy it!