What is better, a serum or a cream?

Sometimes I get asked questions like this. I call this type of question a Tardis (as seen in the TV series ‘Dr Who’, scared me to death as a kid but I’m OK now) question because it looks like its only a tiny question when in fact, it’s massive.  Well when I say it’s a massive question, that’s what I hear, the person who asked it still thinks I’m going to give them a quick, one word answer, usually one that starts and ends in the word ‘serum’ but I don’t…

If you are one of those people who come on here and get the shits with my pedestrian thinking-though-a-problem post then the other quick answer to the question is that there is no simple answer to this question as it depends on how you are defining each of the parts – better, serum, cream.

Another quick answer is for me to assume  that by better you mean works better / delivers results more efficiently;  for serum you are talking about a water based gel serum formula and for cream you are talking about a non-ionic or traditional soap style emulsion (soap meaning it has an anionic emulsifier holding it together, like in the good old days when that’s all we had).  With all that in mind I would say ‘well that depends on the active you are trying to deliver and its concentration I guess’.

By now you might be either wanting to punch me or you can start to see how much of a Tardis this question really is.

I’m not well read in philosophy enough to know if this type of thinking is truly reductionist but it certainly feels like it might be to me. I get a lot of questions like this and attribute  it to the fact that people have access to an awful lot of information and seek to distill it down to something simple and easily digestible so they can absorb the data into their mindset and so they can use it in their marketing.  So, you might have a situation where a brand is trying to justify why they are now telling their clients to use a serum and a cream when before creams did it all.  They read online about how good and potent serums are and then decide that the easiest way to sell their new range addition is to suggest that serums are the best way to get fast-targeted results from actives. This relegates the creams to the status of generalists or ‘slower performers’ or something else entirely, most brands find a way to make room and in doing so, some brand owners get the wrong idea about serums vs creams.

So this is how I really go about thinking about this question when it appears.

1. Identify the active(s) that we are talking about and investigate their chemistry.
   1. Actives are the ingredients in a product that are mostly responsible for the big-hitting results be they moisturising, brightening, colour correcting, tightening or cleansing.  Finding out if the active(s) are oil or water soluble,  their shape and size, their chemistry in terms of polarity, affinity for the skin etc is really important. It is also vitally important to have an appreciation for where the active(s) have to get to in order for them to work.  Are we talking the top layer epidermis or right down at the dermal/ epidermal junction.  Knowing more about the active will help us decide how best to deliver it. For me, this step always includes a review of scientific literature to see if there is any dermal penetration data that I can use to help inform my formulating.
2. Identify the activity level of the product.
   1. Not all cosmetic actives are easy to formulate with and some will be very hard to stabilise in an emulsion, especially when present at very high levels.  It is worth looking into this early as the answer may not be what is best but what is possible.  I think this is one reason why people automatically assume serums are better,  because they can, in many situations, simply hold more active than a typical cream base.   However, more isn’t necessarily better and so holding this conclusion in mind as an absolute law is not that helpful.
3. Delve into how the customer will experience the product.
   1. This includes both the packaging you wish to use and the application data – how much, how often, with what?  If you make a serum to deliver a peptide to soothe and restore moisture to chronically dry skin there is a good chance that your customers will immediately apply a moisturising cream over the top of it unless the serum feels sufficiently protective.  This co-application of products may undo your carefully thought out delivery system plans and render a serum-only product a bit of a failure.
4. Reflect on what your customer are used to.
   1. I’ve said it before and am saying it again (yes I do sound like your mother), you get zero results if the product never leaves the shelf.  Sometimes we have to pull back from the idea-on-paper scientific solution to a problem in order to create something that customers will relate to.  Brand owners need not despair completely at that news, often you can warm customers up by scaffolding your approach – give them something familiar first then add to your range with more interesting and advanced products later.  That’s a good way of building trust.

Serums and creams present different sets of challenges and benefits to the cosmetic formulator. It can be easier to load up a serum with heaps of actives but it can be harder to get said serum to feel moisturising, un-sticky and nutritive.  Creams have the benefit of being able to accomodate both oil and water soluble actives in the same product, often with their own specific delivery systems but active levels are limited by the fragility of the emulsion structure.

In general, my best advice would be to avoid reducing your thinking to this ‘serum vs cream’ mentality as it may well check-mate you in future.  It is far better to talk about why you chose a serum for THIS formula and a cream for THAT and talk to the specifics of each rather than trying to make sweeping general statements.

I hope that has been somewhat helpful.

Amanda