It's been dubbed the 'pink tax': an inexplicable mark-up in pricing which sees women paying a premium on the same products as men, whether it's plain cotton T-shirts, pens, razors, designer perfume or even just shower gel.

After a recent investigation found that the average price difference between men and women's products is around 36 per cent, the debate has been thrust into public spotlight once more.

And now a petition has been launched, urging the executive vice president of Boots, Simon Roberts, to 'charge women fairly' when it comes to like-for-like products.

Scroll down for video

Studies suggest that women are being ripped off when it comes to buying the same products as men. A quick Boots shop showed that women's products like deodorant, razors and shaving gel cost almost 8% more

Left to right: men's disposable razors, shaving cream, deodorant, shower gel, and moisturiser all cost less

The petition, which has garnered 41,000 signatures, has a manifesto that reads: 'Women already buy things that men don't have to buy, like make-up, hair products and tampons which are taxed as luxuries, plus we earn less than men on average across our lifetimes.'

But it raises an important question: instead of paying more for pink, scented, beautifully-packaged versions of male-orientated products, should we bother buying them at all?

Skincare expert Sharon Hilditch told FEMAIL that, when it comes to skincare at least, there is a difference. 'Testosterone determines the masculine characteristics of male skin and gives it a different structure to female skin,' she said.

'While every man’s skin is unique, in general, male skin – on both the face and the body - is thicker, oilier and ages differently. Men will benefit from a tailored approach to skincare.

'Male skin is about 20 per cent thicker than a females and therefore doesn’t age in the same way. Men have more sebaceous glands and sebum production is double that of a female so a male's skin tends to be oilier and more prone to impurities and acne.

'It is also less prone to become dry unlike a more mature female's. Obviously dry, dehydrated skin looks older.

Unity Blott, 26, from London, bought a haul of Boots products from the men's and women's section; the men's products cost on average 7.5% more, with little or no difference in overall quality in some cases

'Men tend to prefer a no-frill approach with simplicity being key whereby the female counterpart wants to indulge and awaken the senses with smells and look and feel.

'Female products tend to address the ageing factor as their skin is thinner and we look for products that lock moisture in and with more innovative and powerful active ingredients that address the ageing and photo damage.'

She added: 'The price will vary as female products tend to incorporate more hi-tech anti-ageing ingredients or actives that brighten and glow.'

With that in mind, writer Unity Blott, 26, from London, decided to put those all-important products to the test to see if we really are being ripped off.

Heading to high street giants Boots and Topshop, she set out to see whether the sexist surcharge was justified or not. Here's what she found...

The Change.org petition, calling for the executive vice president of Boots Simon Roberts to review its 'sexist pricing', has now had more than 34,000 signatures

After loading her basket with moisturiser, shaving gel, disposable razors and shower gel, Unity pitted the male and female items against each other to see if women really are being ripped off

The anti-ageing day cream

While some commentators have compared Clarins' more expensive women's moisturiser to the ClarinsMen £29 Moisture Balm, the beauty assistant in Boots assured me that ClarinsMen Line Control Balm was the closest equivalent.

Just one pound cheaper at £41 (a difference of 2.4 per cent), it's not going to leave you hugely out of pocket, and the two products are certainly the closest in price.

ClarinsMen Line Control Balm, 50ml: £41

The balm's lightweight formula is designed to iron out wrinkles on your face and neck without leaving a greasy finish. Clarins recommends using it 'in the morning after shaving' or at night. Not having any stubble to speak of, I used it before bed and found it had a nice, lightweight texture that left my skin feeling smooth - even my boyfriend commented that it felt extra soft.

Of course, I haven't been using it for long enough to ascertain its anti-ageing qualities, but one online reviewer called it 'a joy to use morning and night'.

ClarinsMen Line Control Balm cost £41, left, while Clarins Multi-Active Day Cream for women, right, was £42

Clarins Multi-Active Day Cream, 50ml: £42

Like its masculine counterpart, this cream aims to fight the early signs of ageing - so it's not for someone who already has deep-set wrinkles.

It has a thicker texture than the men's balm, and as a result it felt quite heavy on the skin - perhaps a bit much to wear under your daily make-up.

However, some online reviewers claim they've suffered bad reactions to the product, with irritated and spotty skin. As day creams go, I'd probably go for the men's Line Control Balm as it's lighter (and £1 cheaper).

The shave gel

I've always been baffled at the cost of women's gels compared to men's, though it's worth remembering that men's shave gel isn't designed for legs and women's gel isn't designed for faces and necks.

But does that mean we should be paying up to 69 per cent more? I stuck to trusted brand Gillette, whose men's shave gels start at £1.85 for a 200ml bottle and £3.49 for women's.

I went for the cheapest version of 'sensitive' shave gel, reasoning this would be the fairest comparison.

Unity found that Gillette Classic Shave Gel Sensitive, left, produced a better lather than the women's version despite costing 69% less at £2.10 compared to £3.55

Gillette Classic Shave Gel Sensitive, 200ml: £2.10

This comes in a plain black/blue bottle and certainly doesn't have the feel of a premium product. The gel itself came out a radioactive green colour with a pungent 'manly' smell that was a little overpowering. But it felt thicker and lathered a lot more easily than the women's version.

Gillette Satin Care Pure & Delicate Shave Gel, 200ml: £3.55

The bottle comes in a much more feminine design, all swirly writing and floral patterns. But while it promises a 'rich lather', it felt a bit thin on the ground compared to the men's version.

Perhaps it offers a more 'luxury' shaving experience on the whole, but I'm not convinced it warrants the 69 per cent price hike. I'll be sticking to men's shaving gel from now on.

The £2.10 Gillette Classic Shave Gel Sensitive came out a radioactive green, left, while the £3.55 Gillette Satin Care Pure & Delicate Shave Gel was a different colour and texture

The deodorant

Mitchum commonly tops lists as one of the most effective antiperspirant deoderants, but why does the women's version cost 7 per cent more than the men's 'Ice Fresh'?

Mitchum Advanced Men 48HR Protection Ice Fresh Anti-Perspirant & Deodorant, 41g: £2.99

The manufacturers call it their 'most advanced formula ever' and its oxygen control technology promises to keep you dry for 48 hours. I've been a fan of the women's version for years, but the only real difference I could see from trying them both out was a slightly harder texture and some ultra-manly packaging (dark green and blue as opposed to pastel hues).

Mitchum Advanced Women 48HR Protection Unscented Anti-Perspirant & Deodorant, 41g: £3.20

Reviewers on Boots.com call it the 'best deodorant yet' but is it any better than the men's version? Not really. While I found it softer and therefore slightly easier to apply, it didn't offer any magical properties that made it worth the mysterious 7 per cent price hike.

Unity could see no difference between the men and women's Mitchum deoderant, apart from the price

No7 Men Energising Moisturiser, left, was 55p cheaper than the women's Essential Moisture Day Cream, right

The moisturising face cream

Like with the Clarins anti-ageing creams, the main difference here appears to be the packaging and that's probably the reason behind the 55p price difference. But does the women's version really need to come in a fancy glass pot with a rose-pink box? Probably not.

No7 Men Energising Moisturiser, 50ml: £8.95

This comes in a simple black tube and could almost pass for a hotel freebie. But with added SPF 15 and an added boost of vitamin C, it's serious skincare that has earned the product a five-star rating on Boots.com. While I wasn't keen on the 'refreshing' smell (Lynx Africa comes to mind), my skin definitely felt pepped up after applying a few blobs as part of my morning skincare routine.

No7 Essential Moisture Day Cream, 50ml: £9.50

This fragrance-free day cream was a real find, and perfect for dry winter skin. While I wasn't convinced by the bulky packaging or deceptively small quantities - I'm not sure it would last more than a couple of weeks - it left my skin feeling soft and supple.

Unity tries out No7's moisturising day creams, and is rather taken by the cheaper £8.95 men's version

Radox Men Feel Sporty with Watermint & Sea Minerals 2in1 Shower & Shampoo, left, was £1 - almost half the price of the women's version, Radox Uplifting Pink Grapefruit & Basil Shower Gel, right, which was £1.99

The shower gel

Radox bath and shower products come in a mind-boggling array of shapes, sizes and scents. The alluringly-named 'Men feel sporty' two-in-one shampoo and conditioner was on special offer at £1, while the prettily-packaged women's shower gel was almost twice the price at £1.99.

Radox Men Feel Sporty with Watermint & Sea Minerals 2in1 Shower & Shampoo, 250ml: £1

This multitasking 'shampoo and shower gel' is found only in the men's section of your local pharmacy or supermarket. While I wouldn't personally use shower gel in my hair, it was a perfectly acceptable soap alternative that left my skin feeling clean and refreshed. Minus points for its slightly sterile, masculine smell.

Radox Uplifting Pink Grapefruit & Basil Shower Gel 250ml, £1.99

I was a big fan of this gel, although I couldn't help but ponder why the women's equivalent of 'feel sporty' was 'feel uplifted'. It had a sharp, fruity smell, but it seems a wasted opportunity for it not to double up as a shampoo like the men's version.

Gillette's men's disposable razors cost just 4p each, while the women's equivalent cost £1 each

The razor

Again, the mind boggles at the dazzling array of razors on offer (Boots alone stocks 77 varieties for women and 194 for men). While you can spend more than a day's wages on the high-end versions, I thought the fairest comparison would be the trusty old disposable from Gillette.

Gillette Blue II Mens Disposable Razors 10 pack, £4.25 (4p each)

At 4p a pop (less than 5 per cent of the cost of the women's version) this represents the biggest price discrepancy out of all the products I tried. I used it with the Gillette Classic Shave Gel Sensitive (see above) and it did just a good a job as any women's razor I've tried.

Gillette Simply Venus 3 Women's Disposable Razors 4 pack, £4 (£1 each)

This is my usual razor of choice, and after trying out the men's version I've decided to stick with it. With a comfortable rubber handle and a pivoting head, it's easy to use and feel like you're using a 'proper' razor as opposed to something you found in your dad's toolbox.

Unity tries out a Gillette men's razor and shaving gel, left, and her usual Simply Venus, right

The T-shirt

Not a beauty product but still worth mentioning. There is a massive 50 per cent mark-up between these basic white tees from Topshop and Topman. They're both 100 per cent white cotton, 'classic fit' and machine washable, so why does the one that undoubtedly uses more material, cost £4 less than the other?

Topman White Roller Crew Neck T-Shirt, £8

After trying on both styles, I was none-the-wiser as to why there was such a big difference in price. The tee comes in six sizes, but I won't be rushing out to buy one instead of my preferred Topshop wares - the style was baggy and swamped my figure.

Topshop Roll Up Tee, £12

It costs 50 per cent more than its male counterpart and only comes in three sizes, but in spite of that I'd still pick this one over the Topman version. It hangs more easily and has a slightly slimmer, more flattering fit.

Topman's White Roller Crew Neck T-Shirt was £8, while Topshop's Roll Up Tee cost 50% more at £12

MEN'S PRODUCTS ClarinsMen Line Control Balm, 50ml: £41 Gillette Series Classic Shave Gel Sensitive, 200ml: £2.10 Mitchum Advanced Men 48HR Protection Ice Fresh Anti-Perspirant & Deodorant, 41g: £2.99 No7 Men Energising Moisturiser, 50ml: £8.95 Radox Men Feel Sporty with Watermint & Sea Minerals 2in1 Shower & Shampoo, 250ml: £1 Gillette Blue II Mens Disposable Razors 10 pack, £4.25 (4p each) Topman White Roller Crew Neck T-Shirt, £8 TOTAL = £66.77 Advertisement

WOMEN'S PRODUCTS Clarins Multi-Active Day Cream, 50ml: £42 Gillette Satin Care Pure & Delicate Shaving Gel, 200ml: £3.55 Mitchum Advanced Women 48HR Protection Unscented Anti-Perspirant & Deodorant, 41g: £3.20 No7 Essential Moisture Day Cream, 50ml: £9.50 Radox Uplifting Pink Grapefruit & Basil Shower Gel 250ml, £1.99 Gillette Simply Venus 3 Women's Disposable Razors 4 pack, £4 (£1 each) Topshop Roll Up Tee, £12 TOTAL = £75.12 Advertisement

The verdict:

My initial Boots shop came to £63.25 for women's products and £58.77 for men's, with a total difference of more than 7.62 per cent. If you factor in the Topshop and Topman T-shirts, that difference climbs to 12.5 per cent.

While there are certainly some women's products I'll be sticking to (razors and T-shirts), it's definitely worth saving yourself some cash by opting for things that come in blue packaging.

See you in the men's aisle!

A Boots spokesperson said: 'At Boots UK, we are committed to offering all of our customers great value and quality.

'We have clear pricing principles that ensure all of our products are priced individually based on a range of factors including formulation, ingredients, and market comparison and were surprised and disappointed to see recent examples in the press that did not reflect our own standards.

'We immediately conducted a review on all Boots own brand and proprietary ranges to better understand the cited examples.