What’s the difference between physical and chemical sunscreens? And which one should you choose?

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Sun exposure can accelerate ageing, cause skin burns, erythema (a skin reaction), skin cancer, melasmas (or sun spots) and other forms of hyperpigmentation – all triggered by solar ultraviolet radiation.

Approximately 80% of skin cancer cases in people engaged in outdoor activities are preventable by decreasing sun exposure. This can be done in lots of ways including wearing protective clothing or sunscreens.

But not all sunscreens work in the same way. You might have heard of “physical” and “chemical” sunscreens. What’s the difference and which one is right for you?

How sunscreens are classified

Sunscreens are grouped by their use of active inorganic and organic ultraviolet (UV) filters. Chemical sunscreens use organic filters such as cinnamates (chemically related to cinnamon oil) and benzophenones. Physical sunscreens (sometimes called mineral sunscreens) use inorganic filters such as titanium and zinc oxide.

These filters prevent the effects of UV radiation on the skin.

Organic UV filters are known as chemical filters because the molecules in them change to stop UV radiation reaching the skin. Inorganic UV filters are known as physical filters, because they work through physical means, such as blocking, scattering and reflection of UV radiation to prevent skin damage.

Nano versus micro

The effectiveness of the filters in physical sunscreen depends on factors including the size of the particle, how it’s mixed into the cream or lotion, the amount used and the refraction index (the speed light travels through a substance) of each filter.

When the particle size in physical sunscreens is large, it causes the light to be scattered and reflected more. That means physical sunscreens can be more obvious on the skin, which can reduce their cosmetic appeal.

Nanoparticulate forms of physical sunscreens (with tiny particles smaller than 100 nanometers) can improve the cosmetic appearance of creams on the skin and UV protection, because the particles in this size range absorb more radiation than they reflect. These are sometimes labelled as “invisible” zinc or mineral formulations and are considered safe.

So how do chemical sunscreens work?

Chemical UV filters work by absorbing high-energy UV rays. This leads to the filter molecules interacting with sunlight and changing chemically.

When molecules return to their ground (or lower energy) state, they release energy as heat, distributed all over the skin. This may lead to uncomfortable reactions for people with skin sensitivity.

Generally, UV filters are meant to stay on the epidermis (the first skin layer) surface to protect it from UV radiation. When they enter into the dermis (the connective tissue layer) and bloodstream, this can lead to skin sensitivity and increase the risk of toxicity. The safety profile of chemical UV filters may depend on whether their small molecular size allows them to penetrate the skin.

Chemical sunscreens, compared to physical ones, cause more adverse reactions in the skin because of chemical changes in their molecules. In addition, some chemical filters, such as dibenzoylmethane tend to break down after UV exposure. These degraded products can no longer protect the skin against UV and, if they penetrate the skin, can cause cell damage.

Due to their stability – that is, how well they retain product integrity and effectiveness when exposed to sunlight – physical sunscreens may be more suitable for children and people with skin allergies.

Although sunscreen filter ingredients can rarely cause true allergic dermatitis, patients with photodermatoses (where the skin reacts to light) and eczema have higher risk and should take care and seek advice.

What to look for

The best way to check if you’ll have a reaction to a physical or chemical sunscreen is to patch test it on a small area of skin.

And the best sunscreen to choose is one that provides broad-spectrum protection, is water and sweat-resistant, has a high sun protection factor (SPF), is easy to apply and has a low allergy risk.

Health authorities recommend sunscreen to prevent sun damage and cancer. Chemical sunscreens have the potential to penetrate the skin and may cause irritation for some people. Physical sunscreens are considered safe and effective and nanoparticulate formulations can increase their appeal and ease of use.The Conversation

Yousuf Mohammed, Dermatology researcher, The University of Queensland and Khanh Phan, Postdoctoral research associate, Frazer Institute, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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  • Managing Chronic Pain (Realistically!)

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    Realistic chronic pain management

    We’ve had a number of requests to do a main feature on managing chronic pain, so here it is!

    A quick (but important) note before we begin:

    Obviously, not all chronic pain is created equal. Furthermore, we know that you, dear reader with chronic pain, have been managing yours for however long you have, learning as you go. You also doubtlessly know your individual condition inside out.

    We also know that people with chronic health conditions in general are constantly beset by well-meaning unsolicited advice from friends and family, asking if you’ve heard about [thing you heard about 20 years ago] that will surely change your life and cure you overnight.

    It’s frustrating, and we’re going to try to avoid doing that here, while still offering the advice that was asked for. We ask you, therefore, to kindly overlook whatever you already knew, and if you already knew it all, well, we salute you and will not be surprised if that’s the case for at least some readers. Chronic pain’s a… Well, it’s a chronic pain.

    All that said, let’s dive in…

    How are you treating your body right now?

    Are you hydrated; have you eaten; are you standing/sitting/lying in a position that at least should be comfortable for you in principle?

    The first two things affect pain perception; the latter can throw a spanner in the works if something’s not quite right.

    Move your body (gently!)

    You know your abilities, so think about the range of motion that you have, especially in the parts of your body that hurt (if that’s “everywhere”, then, our sympathies, and we hope you find the same advice applies). Think about your specific muscles and joints as applicable, and what the range of motion is “supposed” to be for each. Exercise your range of motion as best you can (gently!) to the point of its limit(s) and/or pain.

    • If you take it past that limit, there is a good chance you will make it worse. You don’t want that.
    • If you don’t take it to the limit, there is a good chance your range of movement will deteriorate, and your “safe zone” (i.e., body positions that are relatively free from pain) will diminish. You definitely don’t want that, either.

    Again, moderation is key. Yes, annoying as the suggestion may be, such things as yoga etc can help, if done carefully and gently. You know your limits; work with those, get rest between, and do what you can.

    For most people this will at least help keep the pain from getting worse.

    Hot & Cold

    Both of these things could ease your pain… Or make it worse. There is an element of “try it and see”, but here’s a good general guide:

    Here’s How to Choose Between Using Ice or Heat for Pain

    Meditation… Or Distraction

    Meditating really does help a lot of people. In the case of pain, it can be counterintuitively helpful to focus for a while on the sensation of the pain… But in a calm, detached fashion. Without judgement.

    “Yes, I am experiencing pain. Yes, it feels like I’m being stabbed with hot knives. Yes, this is tortuous; wow, I feel miserable. This truly sucks.”

    …it doesn’t sound like a good experience, does it? And it’s not, but paying it attention this way can paradoxically help ease things. Pain is, after all, a messenger. And in the case of chronic pain, it’s in some ways a broken messenger, but what a messenger most needs is to be heard.

    The above approach a) is good b) may have a limit in how long you can sustain it at a time, though. So…

    The opposite is a can be a good (again, short-term) approach too. Call a friend, watch your favorite movie, play a video game if that’s your thing. It won’t cure anything, but it can give you a little respite.

    Massage

    Unless you already know this makes your pain worse, this is a good thing to try. It doesn’t have to be a fancy spa; if the nature of your pain and condition permits, you can do self-massage. If you have a partner or close friend who can commit to helping, it can be very worth them learning to give a good massage. There are often local courses available, and failing that, there is also YouTube.

    Here’s an example of a good video for myofascial release massage, which can ease a lot of common kinds of chronic pain:

    !

    Some quick final things to remember:

    • If you find something helps, then it helps, do that.
    • That goes for mobility aids and other disability aids too, even if it was designed for a different disability. If it helps, it helps. You’re not stealing anyone’s thunder (or resources) by using something that makes your life easier. We’re not in this life to suffer!
    • There is no such thing as “this pain is not too much”. The correct amount of pain is zero. Maybe your body won’t let you reach zero, but more than that is “too much” already.
    • You don’t have to be suffering off the scale to deserve relief from pain

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  • Honeydew vs Cantaloupe – Which is Healthier?

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    Our Verdict

    When comparing honeydew to cantaloupe, we picked the cantaloupe.

    Why?

    In terms of macros, there’s not a lot between them—they’re both mostly water. Nominally, honeydew has more carbs while cantaloupe has more fiber and protein, but the differences are very small. So, a very slight win for cantaloupe.

    Looking at vitamins: honeydew has slightly more of vitamins B5 and B6 (so, the vitamins that are in pretty much everything), while cantaloupe has a more of vitamins A, B1, B2, B3, C, and E (especially notably 67x more vitamin A, whence its color). A more convincing win for cantaloupe.

    The minerals category is even more polarized: honeydew has more selenium (and for what it’s worth, more sodium too, though that’s not usually a plus for most of us in the industrialized world), while cantaloupe has more calcium, copper, iron, magnesium, manganese, phosphorus, potassium, and zinc. An overwhelming win for cantaloupe.

    No surprises: adding up the slight win for cantaloupe, the convincing win for cantaloupe, and the overwhelming win for cantaloupe, makes cantaloupe the overall best pick here.

    Enjoy!

    Want to learn more?

    You might like to read:

    From Apples to Bees, and High-Fructose Cs: Which Sugars Are Healthier, And Which Are Just The Same?

    Take care!

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  • The Keys to Good Mental Wellbeing

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    The Nine Keys To Good Mental Wellbeing

    Today’s main feature is a bit “pop psychology”, but it has its underpinnings in actual psychology, and is especially useful if approached from that angle.

    What it’s most popularly enjoyed as:

    • A personality-typing system.
    • People love little quizzes and identifiers and such.

    What it’s actually really useful as:

    • A tool for understanding why people (including ourselves) are the way we are
    • A foundational knowledge for living better ourselves, and helping others too

    This stems from the fairly simple principle, uncontroversial in psychology:

    • We have needs, desires, and aversions
    • We act in a way that tries to get our needs met and avoid suffering
    • Thus: Need/Fear → Motivation → Action

    The Enneagram

    The Enneagram (ἐννέα = “nine” in Ancient Greek) system posits that we each have one fundamental need/fear (from a list of nine) that’s strongest for us. A deep-seated insecurity/longing, that we’ll go to almost any lengths to try to meet. Sometimes, in good ways, sometimes, bad.

    The Nine Basic Fears/Insecurities, And Their Corresponding Needs/Desires:

    1. Fear of being a fundamentally bad, wrong person / Need to be good and correct
    2. Fear of being fundamentally unloveable / Need to be loved
    3. Fear of being fundamentally worthless / Need to be valued
    4. Fear of being like everyone else / Need to be different
    5. Fear of being useless / Need to be useful
    6. Fear of being outcast / Need to have a set place in the group
    7. Fear of missing out / Need to experience things
    8. Fear of being hurt or controlled / Need to be in control
    9. Fear of conflict / Need to be at peace

    Of course, most of us have most of these fears/needs to some extent, though usually one will stand out—especially if we aren’t managing it well. The less healthy our coping mechanisms, the more obvious it is how we’re trying to overcompensate in some fashion. For example:

    1. A person who fears being wrong and so becomes a perfectionist rules-abider to a fault
    2. A person who fears being unloveable, and so exaggerates problems to get pity, as the next best thing
    3. A person who fears being worthless, and so exaggerates their accomplishments in order to be admired and valued
    4. A person who fears being like everyone else, and so descends into a “nobody could ever possibly understand me” black hole of pathos.
    5. A person who fears being useless, so burns themself out trying to be an omnicompetent Leonardo da Vinci without ever actually taking the time to stop and smell the flowers as Leonardo did.
    6. A person who fears being outcast, so becomes clingy, passive-aggressive, and suspicious
    7. A person who fears missing out, so tries to experience all the things all the time, ruining their health with dizzying highs and crushing lows.
    8. A person who fears being hurt or controlled, so becomes aggressive and domineering
    9. A person who fears conflict, so shuts down at the slightest hint of it

    If we have healthier coping mechanisms, these same nine people can look a lot different, but in much more subtle ways because we’re not trying to overcompensate so badly:

    1. A person who lives their life rationally by principles that can be adapted as they learn
    2. A person who loves and is loved, as perhaps the most notable part of their character
    3. A person who sets reasonable goals and accomplishes them, and seeks to uplift others
    4. A person who creates and innovates, enriching their own life and the lives of others
    5. A person who is simply very competent and knowledgeable, without overstretching
    6. A person who is dependable and loyal, and a reliable part of something bigger than themself
    7. A person who is fun to be around and loves trying new things, while also knowing how to relax
    8. A person who develops their leadership skills and is a tower of strength for others
    9. A person who knows how to make peace and does so—by themself, and with others

    By being aware of our own fears/insecurities that may drive our motivations and thus underpin our behaviors, we can usually manage them in a much more mindful fashion. Same goes when it comes to managing interactions with other people, too:

    • Letting the Type 3 know you value them, not their accomplishments or what they can do for you.
    • Appreciating the Type 5’s (varied or specialist) skills and knowledge.
    • Giving love to a Type 2 unprompted, but on your own terms, with your own boundaries.
    • And so on for other types

    Or for yourself…

    • As a Type 8, remembering that you can let go sometimes and let someone else be in charge.
    • As a Type 1, catching yourself holding yourself (or others) to impossible standards, and then easing up on that a little.
    • As a Type 9, remembering to stand up for yourself and others, however gently, but firmly.
    • And so on for other types

    If you’re unsure what to focus on, ask yourself: what’s your worst nightmare or greatest daydream? Then work out what it is about that, that makes it feel so bad or good.

    Then, approach things mindfully. Catch yourself in your unhealthy coping mechanisms, and find healthy ones instead.

    What if I get my type wrong? Or I get someone else’s type wrong?

    Obviously it’s better to get them right for maximum effect, but you can never go too far wrong anyway… because we all have all nine of those qualities in us, it’s just a matter of how strong a factor each is for us. So in the worst case scenario, you’ll make someone feel more secure about something that was only a very minor insecurity for them, for example.

    Or in the case of your own type, you may mistakenly think you’re acing being the world’s healthiest Type 5, until you realize you’re actually a Type 3 who thought learning all those things would make you more worthy (spoiler: those things are great, but you’re worthy already). Again, not the end of the world! No matter what, you’re learning and growing, and that’s good.

    Want to delve further?

    Read: The Nine Enneagram Type Descriptions (Basic, but more detailed descriptions than the above)

    Read: How The Enneagram System Works (More complex. Now we’re getting into the more arcane stuff we didn’t have time for today—wings and lines, triads, health levels, directions of integration and disintegration, and more)

    Like learning from books? Here are our top two picks, depending on your learning style:

    We’d love to offer a quick free test here, but all the tests we could find either require paid registration or are wildly inaccurate, so we’ll not waste your time.

    However, we do also think that working it out for yourself is better, as it means you have a handle on what those ideas, fears, insecurities, desires, needs, really mean to you—that way you can actually use the information!

    We’ll close by repeating our previous advice: If you’re unsure what to focus on, ask yourself: what’s your worst nightmare or greatest daydream? Then work out what it is about those scenarios that make them so bad or good. That’ll help you find your real fears/needs, such that you can work on them.

    Good luck!

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  • What’s the difference between shyness and social anxiety?
  • How to Find Happiness In Yourself – by Michelle Mann

    10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.

    A lot of books about happiness tell you what to pursue, generally. What things to focus on, and that’s good, but incomplete. This book does cover those things too (complete with academic sources to back up what really works), but also goes further:

    Michelle Mann gives 25 key habits that will cumulatively build happiness, which is what it’s really about. After all:

    • If you watch your favourite movie, you’ll be happy for 90 minutes (or 9 hours if it’s The Lord of the Rings).
    • If you build daily habits that add happiness to you, your surroundings, and those around you, you’ll be happy for life.

    They do also cover happiness while going through difficult times, such as divorce, job loss, illness, or bereavement.

    Sometimes, knowing what we “should” do in theory is the easy part. Where Mann excels here is in providing explanations of each habit. This means that rather than it being some platitude, the principles underlying it are truly understood… and thus motivate us to actually apply the advice and build the habits into our life.

    While the explanations are therefore the greatest value of the book, we do recommend copying out the 25 habits (which are effectively subchapter headings) and putting them somewhere to read often.

    Bottom line: we recommend getting yourself (and/or your loved ones!) a copy of this book. You (and/or they) will be happy you did!

    Order “How to Find Happiness In Yourself: 25 Habits Guaranteed to Help You Live a Happier Life” on Amazon today!

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  • Exercise and Fat Loss (5 Things You Need To Know)

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    It’s easy to think “I’ll eat whatever; I can always burn it off later”, and if it’s an odd occasion, then that’s fine; indeed, a fit and healthy body can usually weather small infrequent dietary indiscretions easily. But…

    You can’t outrun a bad diet

    Exercise can create a calorie deficit, but over time, the body balances this out by adjusting one’s metabolism, leading to a plateau in fat loss—and as you might know, you can’t out-exercise a bad diet. On the contrary, dietary adjustments are crucial for fat loss and body recomposition.

    About that calorie deficit in the first place, by the way: extreme calorie deficits through exercise alone can lead to muscle loss, reduced energy, and thus sabotage long-term fat loss because having muscle mass increases one’s base metabolic rate (while having fat does not).

    Another thing to bear in mind about exercise is that longer workouts without adequate rests in between can cause burnout, injury, or weight gain due to the body doing its best to conserve energy.

    So, a good diet is a necessary condition for both muscle maintenance and fat loss.

    Five Key Diet Tips:

    1. Include foods you love: don’t feel obliged cut out favorite foods that are a little unhealthy; incorporate them in moderation for sustainability.
    2. Keep adjustments small: avoid making drastic dietary changes all at once; make gradual tweaks to prevent feeling deprived.
    3. Prioritize protein: focus on including a protein source in every meal to increase satiety and aid in muscle building.
    4. Avoid low-calorie diets: drastically cutting calories can lead to muscle loss, metabolic adaptation, and overeating.
    5. Embrace diet evolution: changes may not feel sustainable at first, but adjustments over time help achieve long-term balance. You can always “adjust course” as you go.

    For more on all of this, enjoy:

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    Want to learn more?

    You might also like to read:

    Are You A Calorie-Burning Machine?

    Take care!

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  • Replacing Sugar: Top 10 Anti-Inflammatory Sweet Foods

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    For those with a sweet tooth, it can be challenging to indulge one’s desires while also avoiding inflammation. Happily, Dr. Jia-Yia Lui has scientific insights to share!

    Dr. Liu’s Top 10

    We’ll not keep them a mystery; they are:

    • Grapes
    • Goji berries
    • Barberries
    • Persimmons
    • Longans
    • Lychees
    • Raisins¹
    • Applesauce²
    • Plums³
    • Dates

    ¹Yes, these are technically also grapes, but there are enough differences that Dr. Liu tackles them separately.
    ²It makes a difference how it’s made, though.
    ³And dried plums, in other words, prunes.

    For more details on all of these, plus their extra benefits and relevant considerations, enjoy:

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