Lab Notes

The Beginner's Guide to (Evidence-Based) Skincare

Skincare can be overwhelming. With thousands of options, where do you start?  This guide helps you avoid costly mistakes when starting skincare.

Let’s start at the top: why skincare?

Your skin is the largest organ in your body. Every day, it performs the incredibly difficult job of protecting you from the outside world, keeping the good stuff in and the bad stuff out. Good skincare means supporting your skin with the tools it needs to do this for the rest of your life.

We've created this guide to give everyone access to the best1: information about what you should, and shouldn't, do to achieve that goal. We've tirelessly scoured in-depth research, journal articles, lab experiments, and real-world studies to ensure each recommendation is evidence-based and rooted in modern science.

We're scientists and inherent skeptics, so we're going to explain the underlying biological processes of skincare in detail (but not too much detail - this is a beginner's advanced guide, after all).

This guide will be updated with your feedback and as new research emerges. Check the release notes at the bottom to see how it's evolving. Ok, let’s go.

Obvious question: what is "good" skin?

Good skin is healthy skin. While there’s no precise definition for “healthy” skin, the medical consensus is that healthy skin is healthiest when it is well hydrated, not inflamed, and is free from the signs of damage - sun spots, acne marks, and a rough or uneven texture.2

Is this where you tell us we NEED skincare products to get good skin?

Although skincare products can be used, to some degree, to reverse the damage that's already been done, the best benefits from skincare are preventative. Following a skincare regimen is an investment in your health and reducing the risk of skin cancer, sun damage, and disease.

A skincare regimen is what we call the regular use of tools, products, and practices to keep our skin healthy.

Of course, "healthy" skin is a broad spectrum. Where we are on that spectrum determines what each of us can do to support skin's natural3 biological processes to help it become happier4 and healthier.

An important note: when in doubt, or if you have more serious concerns (sensitivity, acne, new or growing moles, etc.), consult a doctor before beginning any new skincare practice or product.

A few things to keep in mind before we start:


There's no such thing as "flawless" skin, and it's not a realistic goal for a skincare regimen. We believe that healthier skin looks and feels better, but remember that so much of the "skin" we see online and in advertising is the work of makeup, strategic lighting, and filters.


Skin is a complex organ. And everyone's is different.5 What works perfectly for someone else might do nothing for you (or worse - cause a breakout or reaction). There are no universal "holy grails" that work for everyone, so focus instead on finding the products that work for you.


Your skin won't change overnight. Some of the best skincare ingredients take weeks or months to provide real benefits,7 despite how they may be marketed by brands or talked up by influencers.

Where to start?

Skincare is a science. And to get good skin, you have to act like a scientist. At the beginning, skincare can feel like a lot of trial and error. And that's a good thing - as long as we're always learning from those experiments.

The best way to learn from experiments is to make them as small and controlled as possible - so we can know what we did, how our skin reacted, and what we learned.

That's why we should start with a simple skincare routine and focus on getting it right. The core products most people should start with are:

  • Cleanser: to clean your face, removing dirt and excess oil that your skin accumulates during the day
  • Moisturizer: to seal in your skin's natural moisture and improve its ability to defend from damage
  • Sunscreen: to keep your skin healthier for longer and keep wrinkles, UV damage, and the risk of skin cancer at bay

Don't take our word for it (yet). Let's talk about what these things do and why you should bother giving them a shot.

1. Cleansers

Simply put, cleansers help you remove the stuff you don't want from the surface of your skin. This includes gunk from the outside world, like dirt, pollutants and bacteria, and the dead skin cells and excess oily secretions that are a natural part of our skin ecosystem (yes, we said ecosystem). If you don't clean it away, this accumulation of dirt and bacteria can lead to issues like acne, irritated skin, blackheads, and sensitivity.

If you wear makeup or sunscreen, those usually utilize some sort of water-repelling ingredients that make them hard to wash with water alone. A cleanser makes it far easier to remove those substances and keep them from clogging your pores.

Regardless of who you are, you should probably be using a cleanser if you have skin that ever comes into contact with the outside world.


Diagram Showing How Skin Cleansers Work

How Cleansers work

In a cleanser, the active ingredient - the ingredients most responsible for removing dirt and excess oil from the skin - are called Surface Active Agents, or surfactants.

Oil and water usually repel one another, making it challenging to wash oil off your face using only water. Surfactants reduce the skin's surface tension and help oil and water stick together in a form that's easy to wash away.

The magic behind surfactants is in their molecular form. They have a polar head, which attracts water, and a non-polar tail, which attracts oil. When surfactants come into contact with water, they arrange themselves into an organized structure called a micelle, with the non-polar tails creating an oil-attracting core and the polar heads creating a water-soluble outer layer. The oil-loving inner core acts like a magnet for dirt and oil, while the water-loving outer layer means that the micellar, and the dirt trapped inside it, are easily washed away when it comes into contact with water.

"Good" Oil vs "Bad" Oil

Although excess oil and dirt to lead to issues with your skin, oils, just like bacteria, are not all created equal. In fact, when we're talking about "oil" in skincare, we're actually talking about lipids. Some of the lipids your skin generates are an essential part of the skin barrier, a set of structures that protect the skin's deeper layers from the outside world. Without these "good" lipids, skin can become raw, and the barrier can become compromised, so it's important to make sure you're using a cleanser that doesn't wash them away.

Sebum is another one of the "good" lipids, but it's also the one most commonly overproduced by your skin, which contributes to making skin look and feel oily. Proper cleansing removes this excess sebum without washing away all of the lipids on the surface of your skin.

What Cleanser should you use?

Cleansers vary significantly in their strength6; the trick is to find one strong enough to effectively remove dirt and oil but not so strong that it irritates7 your skin.

Most cleansers we studied, including very popular ones, are probably too strong for most people8. Not-so-fun fact: that tight, "squeaky clean" feeling you experience after using a cleanser likely means the cleanser is either too strong for you or is leaving residue on your skin9. On the other hand, if you notice blackheads or whiteheads forming after regular use, it probably means your cleanser isn't strong enough for your skin.

There are a few types of cleansers that broadly correlate with strength:

Note: this is just a general guide. The skincare world is loosely regulated, so there are no standards for these categories or their strengths. But you already guessed that, didn't you?


Most people should start with a foaming cleanser, particularly those who wear little makeup and don't have particularly sensitive skin. Surfactants are the reason that cleansers foam. They're also the reason foaming cleansers tend to be stronger than their non-foaming counterparts. Still, there are strong and gentle foaming cleansers out there10. Below you'll see the ingredients we suggest looking out for.


If you have sensitive skin, you should use a non-foaming cleanser. These use few-to-no surfactants and usually leave a softening layer11 that can help people with dry skin. Since these are generally milder than foaming cleansers, they may require a little extra work or need to be paired with an oil cleanser to clean the skin effectively.

What to look for in the Ingredients List?

Our research indicates that the best cleansers should use mild, amino acid-based surfactants that selectively remove sebum and break down amino acids, which hydrate the skin.

  • Mild surfactants like Sodium Cocoyl Glutamate, Sodium Cocoyl Glycinate, Sodium Methyl Cocoyl Taurate, Sodium Lauroyl Methyl Isethionate, Decyl Glucoside, etc.
  • Ingredients that can prevent irritation like Glycerin, Betaine, Allantoin, Panthenol etc. 
  • pH of 4.0-5.0 to minimize irritation. Water usually has a neutral to basic pH which is not great for the skin. Using a low-pH cleanser can balance your skin pH during cleansing.

Tips for Cleansing:

  • Be gentle with your skin when cleansing. We recommend using your hands or a soft silicone brush to lather your face AND neck.
  • Use lukewarm water. Hot water allows more penetration of surfactants which can disturb your barrier. Coldwater, on the other hand, may disrupt barrier repair processes
  • Make sure to rinse the cleanser really well. Some cleansers can leave your face squeaky clean (which we don’t want), that’s usually residual cleanser that is not properly washed off.
  • Don't scrub or lather too long. Keep it to a minute or two to prevent irritation.
  • Most importantly, moisturize immediately right after cleansing. This is when your moisture barrier is at its weakest. Help it by applying a moisturizer right away. It is hard not to wipe your face but applying your moisturizer in the shower can boost its effect and prevent irritation. 

How to know if your Cleanser is working for you?

Too weak? If you feel like your cleanser isn't removing enough dirt and oil, try increasing the amount used or spend more time working it onto the skin. Ensure the cleanser makes contact with all areas of the skin. Massage firmly, making sure to get in the nooks and crooks of your face (e.g. the sides of your nostrils). If this doesn't help, try adding an oil cleanser to your Regimen (if applicable).

Too strong? If your cleanser leaves your face feeling tight, try using less product or reducing the time spent lathering. Sometimes cleansers leave a thin film that can make your skin feel tight, so be sure to rinse thoroughly and use plenty of water. If this doesn't help, switch to a non-foaming cleanser.

2. Moisturizers

There's plenty of evidence that well-hydrated skin is critical to maintaining healthy skin.12 Dehydration is the cause of a wide range of skin problems like acne, inflammation, and even oily skin (which can be the result of the skin producing more oil in an attempt to better retain moisture).

Because skin is porous, it's always losing moisture to evaporation (we call this trans-epidermal water loss, or TEWL). Moisturizers are an easy way to help your skin retain its natural moisture, critical to alleviating and preventing the multitude of skin problems caused by dryness.

Moisturizers also smooth the skin's surface (moisture increases your skin cells' volume and thereby reduces the gaps between them). Some moisturizers also contain substances that fill in bigger gaps like wrinkles, though this is more for cosmetic effect.


Diagram showing how facial moisturizers work on the skin

How Moisturizers work

Unlike cleansers, most of which have a similar mechanism and vary primarily on strength, moisturizers have a wide variety of forms. Good moisturizers should add water, help your skin retain that water, and provide skin barrier protection.

To explain moisturizers, we need to go into a little more detail, starting with four categories of ingredients that any good, modern moisturizer should have:

  • Emollients
    The word "emollient" comes from the Latin emollire meaning "to make soft," and unsurprisingly, emollients make the skin soft and smooth. They are usually made of oils and lipids that flatten the ridges on the surface of the skin to make the skin softer and more pliable. Some also have the ability to repair your natural skin barrier and help heal damaged tissue.
  • Humectants
    From the Latin humere meaning "to be moist." Humectants increase moisture in the skin by either enabling the skin to hold more water, or helping the skin by "holding" water molecules on the skin.
  • Occlusives
    This one comes from the Latin occludo (to "close up") and refers to how occlusives form a protective layer on, or in, the skin to reduce water loss. This keeps our existing moisture and the additional moisture added by humectants in a moisturizer inside the skin. It's a common myth that occlusives clog pores and cause blackheads or folliculitis. In reality, that's very rarely the case.
  • Actives
    "Active" ingredients in skincare are generally proven13 to assist or enhance specific biological processes in your skin. They generally aren't found in low-quality moisturizers, and tbh they're often poorly executed in high-quality moisturizers (tantalizing statement… we'll get to this!).

What to look for in the Ingredients List:

  • Good emollients to make your skin softer like Capric/Caprylic Triglycerides, Dicaprylyl carbonate, or essential fatty acids like Linoleic and Linolenic acid
  • Effective humectants to hold water like Glycerin, Acetamidoethoxyethanol, Hydroxyethyl Urea, Sodium PCA, Sodium Lactate, Amino Acids, etc.
  • Occlusives like Petrolatum, Mineral Oil, Dimethicone, Allantoin and Shea Butter. 
  • Actives: a modern moisturizer should include scientifically proven actives like Ceramides (which in turn should be in the proper ratio with cholesterol and fatty acids.)
  • Moisturizers generally require a pH of 4.0-5.0 to maximize ceramide integration - watch out, many don't!

Tips for Moisturizing:

  • Apply it on wet or damp skin to get the most out of your moisturizer. It not only helps spread it, but it also boosts your skin at its weakest moment.
  • You don't need a lot. Applying a thin layer on your face 2 pumps is usually enough especially when applied on wet skin.
  • Don't forget your neck. It also needs some TLC and applying products up to the neck keeps your skin evenly healthy.

    3. Sunscreen

    Sunscreen is probably the most widely-known skincare product in the world. Even people who don't care about skincare know about it and use it, and that's a very good thing.

    The sun emits three kinds of UV radiation; UVA, UVB, and UVC. The Earth's atmosphere blocks UVC, but we need sunscreen to help us block UVA and UVB.14 Skin cells have a limited capacity to withstand UV before they become damaged, in some cases causing cell mutations.

    The reason the medical community is so worried about sun exposure and UV damage is that just a single mutation of a single cell can lead to skin cancer if your skin can't repair it.15 Thankfully, our body has a built-in defense mechanism called "apoptosis"- where cells undergo programmed cell death and self-destruct rather than mutating into cancer cells. Sunburn is an indication that our cells have destroyed themselves, intentionally, to avoid becoming cancerous.

    Aside from cancer, UV damage also causes wrinkles and sunspots that contribute to aged skin. For these reasons, dermatologists recommend wearing sunscreen all year round, even if you are only briefly exposed to sunlight.


    Diagram showing how sunscreens work on the skin

    How does sunscreen work? What is SPF?

    SPF (Sun Protection Factor) is the multiple of how much longer it takes skin treated with sunscreen to experience sunburn than skin without sunscreen.

    Let's say it usually takes you 15 minutes to experience signs of sunburn. If you wear an SPF 30 sunscreen, you'll experience that same sunburn 30 times slower than with no sunscreen at all. That means that if you're using sunscreen correctly, it would take you 7.5 hours to get burned.

    The issue with SPF, from a skincare perspective, is that it's only a measure of protection against UVB rays. While it's true that UVB rays are more strongly linked to mutations and cancer, UVA penetrates deeper into the skin and causes damage that results in wrinkles and premature signs of aging — and can also result in skin cancer.

    Unfortunately, finding good UVA protection isn't as easy as it should be, especially for people in North America. One way of knowing if your sunscreen has UVA protection is to check if it has a symbol of the word "UVA" with a circle around it, or if it says "broad spectrum" (a term we don't love16). These indicate simply that product has ⅓ the amount of UVA protection as it does UVB protection.

    What to look for in a Sunscreen?

    • SPF of greater than 30
    • Protection against UVA

    Our Faves:

    • Anthelios Ultra-Fluid SPF 50+ Facial Sunscreen
    • Biore UV Aqua Rich Watery Essence SPF 50+
    • Supreme Screen SPF 50+ Hydrating SKINSCREEN™
    • Skinceuticals Physical Fusion UV Defense SPF 50

    How to use sunscreen

    Most sunscreens recommend application 30 min before sun exposure. And, once you're out there, it typically needs to be reapplied every 2 hours. Not because the SPF protection doesn't last, but because every time you sweat, swim, or even wipe your face, some parts of your UV "shield" comes off.17

    Note: although UVB rays are largely blocked by glass, UVA can still penetrate your windows, damage your skin, and cause premature aging, even if you spend the majority of your time indoors.

    Using sunscreen every day is one of the most beneficial habits you can start. It's a simple habit that doesn't take a lot of effort but has compounding effects over time. If it's not part of your regimen already, make it one today.

    How to start your Regimen

    Now that you know what products should be a part of your skincare regimen, you need to know how to use them. Remember, skincare is an adventure of trial and error, but if we try and change too many things at once, we'll never know what worked and what didn't. It's a good idea to try introducing products one at a time.

    A note on introducing new products

    In some cases, it's possible your skin might react negatively to a product, no matter how high quality it is. You want to make sure that you're not allergic to something or that your skin won't hate it before you go ahead and rub it all over your face. That's why we use patch testing.

    Patch testing is the safety practice of testing the product on a small area of the skin before putting it to broader use. Start by applying a small amount of the product behind your ears, just behind your earlobes. If nothing happens, go ahead and apply the product on the most prominent part of your cheekbone below your eye. If you're still reaction free, that's a pretty good sign that you can safely apply the product to the rest of your face and neck.

    How and when to apply products

    Start with the cleanser. We know it seems simple, but cleansing is one of the most important things you can do to get healthy skin and is very often the culprit when it comes to skin issues. The key with a cleanser is balance. You need to find the right amount of contact (foaming) time with your face to cleanse the dirt properly without damaging or aggravating the skin.

    Start with a quarter-sized amount of cleanser and massage it around your skin for a full minute. Believe it or not, bubbles aren't an indication of cleansing, so don't worry if you feel like you have too few as long as you're getting it all over your skin. Afterwards, wash the cleanser with plenty of lukewarm water. There is evidence that hot water may cause surfactants to penetrate your skin, potentially damaging your skin barrier.

    After washing correctly with lots of water, immediately (as in really right away) apply your next step, the moisturizer. Every time you use a cleanser or even apply water to your skin, water gets into your skin and then gets replaced by air. This causes barrier damage. After washing the skin, quickly apply a quarter-sized amount of moisturizer evenly on your face and neck. Again, time is of the essence here. Commercials try to make it look relaxing, but skincare is a race against the clock.

    Finally, apply half a teaspoon of sunscreen to your face, neck, and the back of your neck. Try to do all that in 3 minutes. Then, at night, rinse and repeat (minus the sunscreen). If everything works, you should start seeing results after a couple of weeks of consistent application.

    Conclusion (Here’s the tl;dr you scrolled down for)

    1. Approach skincare like a scientist. There will be some trial and error to find the products that work for you
    2. If you're starting from nothing or looking for a reset, start with:
      • A foaming cleanser (if it's too strong, look for a non-foaming cleanser. If it's not strong enough, work product in longer or add an oil cleanser to remove makeup)
      • A high-quality moisturizer that contains a high ceramide content
      • Sunscreen
    1. Remember to introduce products one at a time; it's the only way to know if they are working or what is causing potential reactions you may experience

    We of course recommend our cleanser and our moisturizer (we don’t yet make an SPF). While we believe they are the best products out there (and we have the research behind us!), we just told you above that even ‘the best’ products don’t work for everyone. Our YMMV guarantee lets you try the products, return them if they don’t work for you, and best of all - IF OURS DON’T WORK FOR YOU WE WILL HELP YOU FIND THE PRODUCTS THAT DO!

    Coming soon: The Intermediate Guide to Science-based Skincare

    The Intermediate Guide builds on the simple 3-step routine we introduce in this guide, adding serums that contain well-studied active ingredients, like antioxidants. We also dive into the concept of "skin types," specific skin issues, including hyperpigmentation, dry skin, oily skin, and more. Oh, and we'll include a heck of a lot more footnotes.

    Tell us if you'd like an early look at the guide before we publish it!

    PS, we're highly feedback-driven. If you have comments on this guide, disagree or would like to challenge something, or just have a question email us at


    • v2.0 09Mar2022 WM
      • added more tips and recommendations
      • corrected pH
      1. “Best” meaning based in high-quality peer-reviewed studies, promising research, or when those are unavailable, grounded in biological principles. ↩︎
      2. There is no precise definition of "healthy" skin, this definition mirrors the general consensus of the medical community ↩︎
      3. "Natural" is probably the most overused and abused word in skincare. How we refer to it here is to highlight that most skincare products simply boost or inhibit the skin's inherent biological processes. ↩︎
      4. “Happy” skin is not a scientific term, but it’s what we use in-house here at Regimen Lab to describe skin that’s so healthy you can see it and feel it. ↩︎
      5. Skin’s "natural" state is influenced by genetics, environment, diet, stress, sleep, etc. Those also affect how your skin will react to different products, ingredients, treatments, etc. ↩︎
      6. "Strength" typically refers to the concentration of surfactant in a cleanser. The "stronger" the cleanser, the better it can clean dirt and oil. ↩︎
      7. That irritation is the result of surfactants penetrating and disturbing the skin's deeper layers. ↩︎
      8. Most people don't realize this because they quickly apply serums and moisturizer after cleansing, masking the irritation - but not necessarily addressing the skin barrier damage! ↩︎
      9. That tight "squeaky" clean feeling means you've either removed those "good" lipids from your skin's surface and opened yourself up to barrier damage, or your cleanser is leaving residue on your face, which can dehydrate the skin. Unfortunately, the skincare industry has come to train consumers that the ‘tight’ feeling means its working, so many of us assume if we don’t feel it - we’re not clean! ↩︎
      10. While foaming is generally associated with strength, many companies add ingredients that increase the foaming effect without adding cleansing strength. Welcome to the complex world of skincare! ↩︎
      11. Often from an ingredient like glycerin, which provides a bit of hydration and doesn't get washed away by the cleanser's surfactants. ↩︎
      12. If you clicked on this, we realize you're probably surprised by this. More on this in an upcoming article, we promise! ↩︎
      13. Well, they ought to be scientifically proven, but beware of wild claims! ↩︎
      14. We also included UVC to see if you're still paying attention ↩︎
      15. We don't mean to do fearmongering here, but sun exposure is a real risk factor. Read more here citation. ↩︎
      16. "Broad-spectrum" is, as of 2011, a marketing claim regulated by the FDA. This study highlights the poor consumer understanding of the term. ↩︎
      17. The FDA allows some products to be marketed as "water-resistant" if they can prove this claim. If you're interested in the test used to approve this claim, see Question 11 here. ↩︎