Dr Sebagh is Cindy Crawford’s Paris-based derm and the expert inspiration behind her mediocre Meaningful Beauty line (which has been reviewed by Truth In Aging readers, such as Lynne without much enthusiasm (although Diane had a more generous verdict). The good doctor’s personal and much more upscale range, the eponymous "Dr Sebagh" has just launched in Barney’s and so I was curious to see if his formulas would improve when left to his own devices.

If anything, they are worse. Especially considering the steep prices. First, I took a look at Dr Sebagh Serum Repair $140.  The first thing that I was struck by was the claim that it “contains 50% hyaluronic acid”. Oh, is that a fact? Actually, I don’t think so.

I once did some digging into products that claim high percentages of hyaluronic acid (sodium hyaluronate) and even half that amount would be a physical impossibility. Most skincare formularies recommend HA be used at a rate of .01% to 1%. Anything more results in a useless, thick goo. Imagine making Jell-O but only using 1/10th the water and you will get the idea. I had lot of fun making a video to demonstrate this.

More plausibly Serum Repair also has hydrolyzed collagen, glycerin and the peptide known as Matrixyl. However, Dr Sebagh seems to be a bit of a micro-phobe as about half the ingredients – seven to be exact – are preservatives including most parabens known to man, the possible neurotoxin, phenoxyethanol, and two irritants.

Priced audaciously at $350, Dr Sebagh’s newest product is Supreme Night Secret, which is supposed to use “the latest biotech cosmetic ingredients to work with the skin’s natural body clock”.  Most of the first 20-odd ingredients are worthless and the rest are not much to write home about. The exception might be an alga and it is this that seems to be the “biotech” ingredient that works with the body clock. I found a patent application that makes all sorts of claims about its ability to repair cellular structures. The amusing part is that this particular algae euglena gracilis lives and multiplies in the absence of light – hence, its use in night cream I would guess. So if you do fork out $350 for Supreme Night Secret, don’t sleep with the light on as you may render this active ineffective.

In order to buy Supreme Night Secret, you’d have to believe in it as there isn’t much else here apart from perfectly good, but not game-changing, ingredients such as shea butter, wheat germ, rosehip and tribehenin. As far as being an active, I’m not sure I understand what this alga does in skincare. Another cosmetic brand, Cellbone, says it “triggers cell metabolism by stimulating calcium release”. But I haven’t found anything to back this up, despite the myriad studies on this it. One of those studies said that euglena gracilis can synthesize tryptophan, an amino acid that is a natural sedative (its in turkey and explains the Thanksgiving nap). So perhaps Supreme Night Secret at the very least will send you off for a good night’s sleep.

See our FIVE BEST recommendations including Five Best for sagging skin, Five Best with vitamin C and Five Best eye creams

Ingredients in Serum Repair: Aqua (Water) - Hydrolyzed Collagen - Sodium Hyaluronate - Glycerin - Butylene Glycol - Carbomer - Polysorbate 20 - Palmitoyl Pentapeptide-3 - Phenoxyethanol - Methylparaben - Butylparaben - Ethylparaben - Propylparaben- Methylchloroisothiazolinone – Methylisothiazolinone

Ingredients in Supreme Night Secret: Aqua (Water), Cyclopentasiloxane, Glycerin, Dicaprylyl Ether, Peg-12, Euglena Gracilis Extract, Caprylic/Capric Triglyceride, Biosaccharide Gum-4, Cetyl Alcohol, Glyceryl Stearate, Butyrospermum Parkii Butter, Cetearyl Alcohol, Dimethicone, Polymethyl Methacrylate, Silanediol Salicylate, Hexyldecanol, Hydrogenated Palm Kernel Glycerides, Caprylic/Capric/Succinic Triglyceride, Phenoxyethanol, Glyceryl Dibehenate, Magnesium Aluminum Silicate, Rosa Canina Fruit Oil, Polyacrylate-13, Peg-75 Stearate, Aroma (Flavor), Tribehenin, Alpha-Glucan Oligosaccharide, Propanediol, Ceteth-20, Steareth-20, Polyisobutene, Chlorphenesin, Caprylyl Glycol, Sesamum Indicum Oil, Glyceryl Behenate, Safflower Oil / Palm Oil Aminopropanediol Esters, Hydrogenated Palm Glyceride, Bht, Wheat Germ Glycerides, Algin, Geranylgeranylisopropanol, Phoenix Dactylifera (Date) Seed Extract, Polysorbate 20, Tocopheryl Acetate, Rhizobian Gum, Sodium Hyaluronate, Potassium Sorbate, Sodium Methylparaben, Tocopherol, Methylparaben, Propylparaben, Butylparaben, Ethylparaben, Ci 14700 (Red4), Isobutylparaben, Magnesium Nitrate, Citronellol, Benzyl Alcohol, Geraniol.