María Monterrubio

If used in moderation, caffeine exerts several health benefits. Those happen with oral ingestion or local application of caffeine to the skin. Many of the advantages of caffeine are well understood. However, others remain controversial. Gain clarity on what oral or topical caffeine can do for your skin, why, and how to handle this powerful biomolecule to obtain the most beneficial results.

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Hi everyone! If you are reading this, I guess your health & fitness New Year’s resolutions may include a skin upgrade. So let’s get into it!

Have you ever wondered whether you are wasting your time by rubbing skincare products with caffeine, for instance, on your eye contour? Or whether oral or topical caffeine does help with other skin issues? Then you are on the right page. Keep reading!

What does happen in your body when you ingest caffeine?

Caffeine is structurally related to some of the nitrogenous bases of the DNA. To be more specific, it is a purine and structurally similar to adenine (A) and guanine (G), two of the four letters in our genetic code or DNA (see the image below).

Adenosine is an adenine nucleoside (see image below). And a signaling molecule within our cells and systems. It acts through binding to adenosine receptors, widespread throughout different tissues in our body, such as the central nervous system or the blood vessels. Adenosine promotes vasodilation when it binds to A2a adenosine receptors, abundant in blood vessels. And caffeine antagonizes that effect. 

That effect of caffeine stems from the structural similarity between caffeine and adenosine. Such resemblance allows caffeine to compete with adenosine for A2a receptors and inhibit their action. When caffeine tethers to those receptors, adenosine cannot bind them and, thus, they remain inactive and do not promote vasodilation. In the brain, adenosine also regulates the release of neurotransmitters (and caffeine can also interfere with that). Those two mechanisms are behind the primarily awakening effects of caffeine.

Therefore, we could say that caffeine acts in the first instance as a vasoconstrictor. Nonetheless, caffeine can activate signaling mechanisms different from those implicating adenosine receptors. And that is how it can also be a vasodilator in certain instances (depending on its concentration and type of blood vessels involved). Indeed, vasodilation can also enhance blood microcirculation depending on the tissue and context. 

As you can imagine, with such biochemistry involved, we cannot take the health effects of caffeine lightly. The European Food Safety Authority (EFSA) recommends up to 400 mg per day (roughly four espresso coffee cups) and no more than 200 mg for pregnant women.

Within that range, caffeine can be beneficial for our bodies. There are scientific studies with large numbers of participants that associate caffeine consumption with a significantly reduced risk of several types of cancer (including skin cancer). Those outcomes might be mostly related to the antioxidant properties of caffeine rather than its vascular effects.

How does caffeine affect your skin?

Caffeine is both fat and water-soluble. That chemical nature allows it to travel freely throughout our entire body and get across the stratum corneum (the outermost, waxy layer of the skin) when topically applied. It also quickly penetrates further down into the epidermis, the dermis, the hair follicles, cutaneous blood vessels, and the fatty tissue underneath the dermis.

Regardless of the amount of caffeine applied, all of it sinks into the various layers of the skin, where it is biologically active. Once there, it quickly gets into the systemic circulation, and our body metabolizes it mainly in the liver and excretes it in the urine (the same as orally taken caffeine). 

When you take caffeine orally, it also reaches the skin (through the blood vessels in the dermis) and works within it. However, given that the oral intake of caffeine should be moderate, the positive effects of oral caffeine on the skin are gained with regular consumption of it.

Then, what skin issues can oral or topical caffeine tackle effectively?

Skin cancer and photoaging

Besides being a psychoactive and also a regulator of blood vessel dilation, caffeine is a powerful antioxidant that helps counteract oxidative stress in the skin due to ultraviolet light exposure (or other external or internal aggressors, such as air pollution or internal toxins).

Years ago, researchers found out that the topical application of caffeine diminished the incidence of benign and malignant skin tumors by increasing the apoptosis (or programmed cell death) of premalignant or malignant cells. 

And now we know that the regular, oral consumption of caffeine is inversely associated with the risk of at least certain skin cancers (such as basal cell carcinoma, which arises from the highly proliferative cells in the innermost layer of the epidermis)¹. 

So, if you like coffee or other sources of caffeine (such as tea), know that as long as you keep your drinking reasonable, you are most probably benefiting your skin (and other organs).

The excellent cutaneous penetration of caffeine and its antioxidant and anti-carcinogenic effects – especially in the epidermis (the outermost skin layer)– raises the possibility of using it to make more effective topical sunscreen formulations. A potential issue here could be that a percentage of caffeine (usually included from 1 to 5% in cosmetics) applied to widespread skin areas would increase the daily dosage of caffeine in your body. And remember, it should be below 400 mg. 

Dark circles and eye puffiness

That is the most widely known effect of topical caffeine. And, yes, if you apply a product with an adequate amount of pure caffeine, it works! Caffeine constricts the vessels around the eye area transiently, hence reducing the accumulation of fluids, dark circles, and swelling near the eyes for a few hours. That said, caffeine will not be the appropriate treatment for your dark circles if the cause behind them is different, such as the accumulation of melanin (pigmentation) due to genetics or sun exposure.

In addition, if you suffer any inflammatory condition (such as eczema, allergies, or ocular rosacea) that exacerbates the dark circles or puffiness around your eyes, topical caffeine can transiently help. But the proper medical treatment of the underlying condition to keep inflammation under control should provide you with longer-lasting internal and external relief. And most probably, you could still apply caffeine.

Skin irritation

If you get some isolated skin redness, swelling, or irritation, topical caffeine can aid in relieving it thanks to its antioxidant, vasoconstrictor, and immune system regulation properties. Diminishing excessive blood flow and oxidative stress will attract lower and less reactive immune system cells into the area. The result? A quieter environment, and a chilled-out immune system, will soothe the skin and hopefully prevent a more persistent irritation.

Rosacea

Rosacea involves the dilation of cutaneous micro-vessels and a degree of skin inflammation and redness. Although hot beverages are generally not recommended for people with rosacea predisposition due to the risk of flares, coffee does not seem to be one of them. 

Despite the previous controversy regarding the benefits of coffee on rosacea, a massive study comprising thousands of women (and spanning decades) has proved that drinking caffeine from coffee significantly decreases the risk of rosacea flares². That means that neither decaffeinated coffee nor other known sources of caffeine have similar effects. The lower amount of caffeine in sources other than coffee or the combination of caffeine with molecules present only in coffee could explain that.

The abilities of caffeine to regulate vasodilation and immune system reactivity seem to keep rosacea flares at bay. Thus, as long as sipping on coffee makes you feel good, there is no reason to stop doing it to improve your rosacea. Just don’t overdo it, and, of course, you choose whether your coffee is hot.

Hair loss (androgenetic alopecia)

Caffeine antagonizes adenosine receptors in the nervous system or the blood vessels. But it also inhibits cellular enzymes called phosphodiesterases (PDE). The inhibition of PDEs activates the metabolism of lipids (lipolysis), which provides the cells with higher energy (ATP). With more ATP available, the cells proliferate more.

The most common type of hair loss in men and women is androgenetic alopecia. It involves the shortening of the growth phase of the hair cycle. And the lengthening of the resting phase (when the hair does not grow anymore and then sheds off). That results in the miniaturization of the hair follicles and shorter hairs in specific scalp areas. In men, the scalp regions with more receptors for androgens (like the hormone testosterone) are affected. In women, the association with androgens is not clear. 

Caffeine penetrates the skin through hair follicles and inter-follicular regions (the skin in-between hair follicles). When it enters the hair follicles, it remains within them for hours. Caffeine stimulates cellular proliferation within the hair follicle and thus helps extend the growth phase, which yields longer hair again. It also inhibits the conversion of testosterone to 5-dihydrotestosterone (a much more potent activator of androgen receptors than testosterone and, therefore, hair loss).

In men and women, topical caffeine can reverse the shortening of the growth phase and, therefore, hair miniaturization and loss. And its effect is similar to that of minoxidil (a medication for hair loss), at least in men³. 

But there’s a caveat here: you need still active hair follicles for caffeine to work, so you should act fast. And, of course, visit your dermatologist ASAP if the results are not good enough or you have waited for too long (caffeine can be an adjuvant to other treatments that require a medical prescription).

Why does caffeine not work for your cellulite?

Caffeine penetration on the skin is independent of skin thickness. Thus, you would think that there should be no problem for topical caffeine to reach the fat deposits of cellulite in the hypodermis and activate their destruction through lipolysis.

But, in most cases, it is not as simple. Why? Because the tissue around those lipid deposits hardens, giving rise to cellulite nodules, and making them quite unreachable for caffeine. That is the reason why most cellulite creams with caffeine are pretty ineffective.

My experience using 5% topical caffeine

I started using The Ordinary Caffeine Solution 5% + EGCG almost two months ago. That is an aqueous, fragrance-free serum with a high concentration of caffeine. 

It also contains a form of a bioactive molecule from green tea, the polyphenol EGCG (an antioxidant). I haven’t gone through the studies from the provider on that EGCG form. Thus, I don’t know how it compares with the actual EGCG from green tea. At the very least, it will act as an antioxidant to preserve the formulation. I bought the serum because of the caffeine content, and I will focus on that now.

I never used a dedicated serum with a high concentration of caffeine before, even though I have had dark circles around my eyes and cuperose on the top of my cheeks since I was a child. Luckily, my skin has an olive undertone that slightly counteracts all that 😉

In 2021 I had several vascular laser sessions done by a dermatologist. Getting rid of dilated (visible) blood vessels around my eyes improves ocular rosacea in my case. I had the last session by the end of October and decided to give caffeine a try to see whether it minimized the dark circles and some swelling I got after the laser on top of my left cheek.

The results: it works, dark circles improve, and the swelling is under control. I suggest applying the caffeine just once a day (I do it in the morning, before moisturizing the skin) for issues like mine.

There are two reasons for that from my point of view. Firstly, caffeine could make your skin drier. And secondly, the chronic use of topical caffeine can lead to a rebound effect if one day you stop it. Free adenosine will suddenly bind the adenosine receptors that caffeine used to block. And might stimulate excessive dilation of your blood vessels after being in almost constant vasoconstriction for a while.

In other words, know when you cannot downplay your dark circles with just topical caffeine (hello moisturizer + makeup pigments!). A product with a dose of caffeine is an excellent addition to your skincare stash only when used in moderation. 

I hope you liked this post. Please feel free to ask me anything about the subject below or on Instagram (@drmariamonterrubio). 

Take care and see you next time!

Love,

María

For your reference:

¹ Increased caffeine intake is associated with reduced risk of basal cell carcinoma of the skin. Song F et al., Cancer Res, 2012; 72 (13): 3282-9.

² Association of caffeine intake and caffeinated coffee consumption with risk of incident rosacea in women. Li S et al., JAMA Dermatol, 2018; 154 (12): 1394-1400.

³ An open label randomized multicenter study assessing the noninferiority of a caffeine-based topical liquid 0.2% versus minoxidil 5% solution in male androgenetic alopecia. Dhurat R et al., Skin Pharmacol Physiol, 2017; 30 (6): 298-305.

Caffeine and its pharmacological benefits in the management of androgenetic alopecia: a review. Völker JM et al., Skin Pharmacol Physiol, 2020; 33 (3): 93-109.

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