By Dr Craig Sheridan MBChB MRCGP BSc (Hons) MSc SEM (Distinction)
Having a sports and exercise medicine background, I am acutely aware of the misinformation delivered to the public about the dubious benefits of sugary sports drinks. It is potentially worrying therefore to now see the drinks industry turning its attention to the growing field of aesthetic medicine. After all, as ‘beauty comes from within’ surely it follows that an ingested product fortified with rejuvenating vitamins, minerals and proteins would have the potential to turn back the clock and enhance beauty? This article seeks to explore the evidence surrounding drinks marketed as being able to improve skin appearance.
Whats in these drinks to justify the claims?
The nutraceutical industry, which explores the health benefits of dietary macro and micronutrients have turned their attention to the cosmetic industry, creating the ‘nutracosmecueticals’ industry (1) – a mouthful even for the food and drinks industry.
The process of aging is a complex one. From the perspective of skin there are many intrinsic and extrinsic factors that contribute to aging. Intrinsic causes include age, genetics and your cells innate ability to self-repair. Extrinsic causes include exposure to toxins such as cigarette smoking as well as solar radiation. Having identified causes of aging skin, the nutracosmecueticals industry has focused on nutrients which in theory are thought to affect these factors. The problem is that there is often quite a jump between theory and proof.
It appears that theories are applied with the following logic. For example:
1. Reduced ability for skin cells to repair is a cause of aging skin.
2. Anti-oxidants help cellular repair (by mopping up free radicals).
3. Berries contain anti-oxidants.
4. Therefore a drink rich in berries is good for your skin right?!
Unfortunately science does not work like this. The answer until proven otherwise is no or maybe. It is a reasonable hypothesis. However a hypothesis is only the first stage of research. The first thing that most research scientists will do when planning an experiment is come up with a theory or hypothesis. Then, given that at this stage they do not know if their theory will be confirmed, they reverse the statement to form a null hypothesis. So rather than starting with the hypothesis ‘Berries contain anti-oxidants and will reduce the effects of skin aging’, they would state a null hypothesis namely ‘Berries contain anti-oxidants but do not reduce the effects of skin aging’.
Their research can then move on by designing and performing experiments which might disprove their null hypothesis (or prove their hypothesis). This might take the form of a trial. For example two identical groups in terms of age, skin complexion, smoking history etc are divided into two groups. One is given a drink containing a specific quantity or berries. The other is given water. Then after a defined period of time objective measurements of skin quality are made or perhaps a validated questionnaire of skin quality is used (validated meaning the questionnaire has been scientifically tested to ensure that it is a reliable tool for measuring the question being asked). If this study finds a difference, then you are part way towards rejecting the null hypothesis and may perhaps be able to conclude that berries are good for your skin.
However, this relies on the study being high quality (so lots of people tested, appropriate statistical analysis and a well-constructed method) and unbiased (it is difficult to trust studies performed by the owner of the product in question as there is an inherent conflict of interest). The scientist performing this study might be out of a job if the findings don’t support the claims the company hope to make, opening the risk of conscious or unconscious manipulation of outcomes and statistics
As it stands, there is just too much of gap in knowledge between the theory and many of the statements made by the nutrocosmeceutical drinks industry and individual drink products coming onto market. This has led unfortunately to potentially unjustified claims about many drinks products marketed as anti-aging or skin nourishing. The next series of blogs therefore aims to look at some of the commonly used nutrients within these anti-aging drinks, to see if there is good evidence to support the claims. In turn we will also focus on certain drinks containing these products and look at the evidence they are citing and see whether their interpretations are indeed justified.
My working theory as it stands is that ‘there is little or no evidence to support the claims behind drinks marketed as anti-aging and skin replenishing’. However, if the studies can convince me otherwise I will happily reject this null hypothesis!
(1)Cosmeceutical Science in Clinical Practice
edited by Neil S. Sadick, Mary Lupo, Diane S. Berson, Zoe Diana Draelos