When it comes to the oh-so important first step in your skincare routine, it's worth splashing the cash, Dr. Gunatheesan tells marie claire.
"You need a high-quality cleanser that effectively removes make up, sunscreen and environmental pollutants, without compromising or drying out your lipid rich skin membrane, whilst maintaining your acidic skin pH," she explains.
The exception: If, however, you're in your twenties, have a normal skin type and don't tend to slather on makeup, you can get away with spending less on a cleanser, she notes.
Alpha-H Balancing Cleanser with Aloe Vera, $37.36 at Adore Beauty
Toner: SAVE (slash, don't buy it)
While it is perhaps the most controversial product of all when it comes to skincare (to buy, or not to buy?), Dr. Gunatheesan says it's one you can largely afford to skip entirely.
"If you have the right cleanser, it's an unnecessary step," she notes.
The exception: "[If you have] super oily skin."
Paul's Choice Pore-Reducing Toner with Niacinamide for Oily Combination Skin 190ml, $29 at Paula's Choice
Serums & Actives: SPEND
Think of serums and active ingredients as the heavy lifters in your skincare routine. Like a set of highly trained special agents, they are deployed to tackle specific skin concerns, such as pigmentation, smoothly and quickly to deliver real results.
However, many of them require certain concentration levels to be effective, or packaging that doesn't compromise the quality of the formula, and that's why spending on high-performing products, for the most part, will reap the rewards in the long run. Dr. Gunatheesan's personal favourites?
"My two favourite multipurpose, super potent actives are niacinamide (vitamin B3) and vitamin C, both of which are important antioxidants that combat hyperpigmentation and wrinkling of the skin," she said.
The exception: "Teenagers, and those in their early twenties without skin issues, but who have invested in a high SPF broad-based sunscreen."
SkinCeuticals C E Ferulic Serum 30ml, $218 at Adore Beauty
Retinol (Retinoids): SPEND
In the case of retinol, the reason for spending is less to do with having the highest concentration or a prescription product, and more about using carefully crafted formulas to actually make a difference to the skin.
"It is not about the highest strength or using prescription retinoic acid, which can be too irritating on most skin," Dr. Gunatheesan says.
"Look for tertiary complex retinols—retinyl-esters that are conjugated with DNA repair enzymes to optimise a slow delivery system for constant depot like release for skin cell renewal."
The exception: If you have blemish-free or sensitive skin.
Drunk Elephant A-Passioni Retinol Cream 1.0% retinol 30ml, $119 at MECCA
Anti-Ageing Creams: SAVE
Surprised? There's actually a very logical reason why anti-ageing creams generally fall on the 'save' side of the spectrum.
"Using a layered multi system approach of day time actives and nighttime Alpha and Beta Hydroxy Acids (AHAs and BHAs), and vitamin A (retinoids) is more efficacious than a blended anti-ageing cream," Dr. Gunatheesan explains.
The exception: None!
Olay Regenerist Micro-Sculpting Night Cream, $24.49 at Chemist Warehouse
If you're trying to decide whether to drop a few extra coins on an exfoliant, the good news is, you're most likely safe to go with the less pricey alternative. And according to Dr. Gunatheesan, chemical exfoliants are the best ones to go with, with lactic acid being her recommended option.
"Lactic acid is great at recalibrating skin to a youthful, slightly acidic pH, and optimising skin renewal and turnover," she says.
The exception: You may want to research and shop around if you have sensitive or easily irritated skin.
The Ordinary Lactic Acid 10% + HA 30ml, $12.70 at Adore Beauty
Now, we know sunscreens are often a deeply personal choice—especially for those of us who have darker skin tones and know the Casper the Friendly Ghost look all too well—so, at the end of the day, whichever sunscreen you like using and will use consistently, regardless of price, will be the one to go with.
That said, if there is any one product in which to invest both your money and discipline, it's sunscreen. Easily the most important step in your routine for both short and long term skin health, good sunscreen formulas that cooperate with your skin type, provide a smooth base for makeup, banish the white cast and actually withstand the Australian sun, do tend to fall into the 'splurge' basket.
And while there are a number of good chemical sunscreens out there (the kind that sits in the skin), Dr. Gunatheesan recommends opting for a well-formulated physical sunscreen (the kind that sits on the skin), where possible.
"Physical is best. Look for zinc and iron oxides to cover a larger spectrum of visible light, UVB and UVA," she says.
Ultra Violette Lean Screen SPF50+ 50ml, $45 at Adore Beauty
Face Masks (Clay and Sheet): SAVE
Think of face masks as your quick-hitting skin boosters, whether that's quickly banishing excess oil or plumping your visage before a party. For the most part, they aren't going to do anything that offers long-term results, so it's more than okay to skimp on face masks if you're not thrilled by the idea of spending too much on them.
"There's really no need [for face masks] if you have a systematic skincare regimen," Dr. Gunatheesan says.
Burt's Bees Hydrating Sheet Mask with Clary Sage, $9.50 at Adore Beauty
Eye Cream: SAVE
Remember when we said toner was the most controversial product? We take that back—eye cream might just take the cake! Having said that, Dr. Gunatheesan says it's not a product you need to spend on, for the most part.
"If you have a high-quality night cream, you could use a small amount, tapping it around the eye area," she says.
The exception: "If orbital pigmentation, wrinkling or puffiness is an issue for you, invest in a good eye cream," she says.
In this case, you're still okay to start on the lower end of the range (usually starting around the $50 mark for a good one), if you have specific concerns regarding the skin around your eyes.
Ole Henrksen Banana Bright Eye Crème 15ml, $57 at Sephora