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.
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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How To Avoid Self-Hatred & Learn To Love Oneself More
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Alain de Botton gives a compassionate, but realistic, explanation in this video:
The enemy within
Or rather, the collaborator within. Because there’s usually first an enemy without—those who are critical of us, who consider that we are bad people in some fashion, and may indeed get quite colorful in their expressions of this.
Sometimes, their words will bounce straight off us; sometimes, their words will stick. So what’s the difference, and can we do anything about it?
The difference is: when their words stick, it’s usually because on some level we believe their words may be true. That doesn’t mean they necessarily are true!
They could be (and it would be a special kind of hubris to assume no detractor could ever find a valid criticism of us), but very often the reason we have that belief, or at least that fear/insecurity, is simply because it was taught to us at an early age, often by harsh words/actions of those around us; perhaps our parents, perhaps our schoolteachers, perhaps our classmates, and so forth.
The problem—and solution—is that we learn emotions much the same way that we learn language; only in part by reasoned thought, and rather for the most part, by immersion and repetition.
It can take a lot of conscious self-talk to undo the harm of decades of unconscious self-talk based on what was probably a few years of external criticisms when we were small and very impressionable… But, having missed the opportunity to start fixing this sooner, the next best time to do it is now.
We cannot, of course, simply do what a kind friend might do and expect any better results; if a kind friend tells us something nice that we do not believe is true, then however much they mean it, we’re not going to internalize it. So instead, we must simply chip away at those unhelpful longstanding counterproductive beliefs, and simply build up the habit of viewing ourselves in a kinder light.
For more on all this, enjoy:
Click Here If The Embedded Video Doesn’t Load Automatically!
Want to learn more?
You might also like to read:
- Escape From The Clutches Of Shame
- To Err Is Human; To Forgive, Healthy
- How To Get Your Brain On A More Positive Track (Without Toxic Positivity)
Take care!
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The Worry Trick – by Dr. David Carbonell
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Worry is a time-sink that rarely does us any good, and often does us harm. Many books have been written on how to fight anxiety… That’s not what this book’s about.
Dr. David Carbonell, in contrast, encourages the reader to stop trying to avoid/resist anxiety, and instead, lean into it in a way that detoothes it.
He offers various ways of doing this, from scheduling time to worry, to substituting “what if…” with “let’s pretend…”, and guides the reader through exercises to bring about a sort of worry-desensitization.
The style throughout is very much pop-psychology and is very readable.
If the book has a weak point, it’s that it tends to focus on worrying less about unlikely outcomes, rather than tackling worry that occurs relating to outcomes that are likely, or even known in advance. However, some of the techniques will work for such also! That’s when Dr. Carbonell draws from Acceptance and Commitment Therapy (ACT).
Bottom line: if you would like to lose less time and energy to worrying, then this is a fine book for you.
Click here to check out The Worry Trick, and repurpose your energy reserves!
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The Brain-Skin Doctor
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Of Brains And Breakouts
Today’s spotlight is on Dr. Claudia Aguirre. She’s a molecular neuroscientist, and today she’s going to be educating us about skin.
What? Why?
When we say “neuroscience”, we generally think of the brain. And indeed, that’s a very important part of it.
We might think about eyes, which are basically an extension of the brain.
We don’t usually think about skin, which (just like our eyes) is constantly feeding us a lot of information about our surroundings, via a little under three million nerve endings. Guess where the other ends of those nerves lead!
There’s a constant two-way communication going on between our brain and our skin.
What does she want us to know?
Psychodermatology
The brain and the skin talk to each other, and maladies of one can impact the other:
- Directly, e.g. stress prompting skin breakouts (actually this is a several-step process physiologically, but for the sake of brevity we’ll call this direct)
- Indirectly, e.g. nervous disorders that result in people scratching or picking at their skin, which prompts a whole vicious cycle of one thing making the other worse
Read more: Psychodermatology: The Brain-Skin Connection
To address both kinds of problems, clearly something beyond moisturizer is needed!
Mindfulness (meditation and beyond)
Mindfulness is a well-evidenced healthful practice for many reasons, and Dr. Aguirra argues the case for it being good for our skin too.
As she points out,
❝Cultural stress and anxiety can trigger or aggravate many skin conditions—from acne to eczema to herpes, psoriasis, and rosacea.
Conversely, a disfiguring skin condition can trigger stress, anxiety, depression, and even suicide.
Chronic, generalized anxiety can create chronic inflammation and exacerbate inflammatory skin conditions, such as those I mentioned previously.
Chronic stress can result in chronic anxiety, hypervigilance, poor sleep, and a whole cascade of effects resulting in a constant breakdown of tissues and organs, including the skin.❞
So, she recommends mindfulness-based stress reduction (MBSR), for the above reasons, along with others!
Read more: Mind Matters
How to do it: No-Frills, Evidence-Based Mindfulness
And as for “and beyond?”
Do you remember in the beginning of the pandemic, when people were briefly much more consciously trying to avoid touching their faces so much? That, too, is mindfulness. It may have been a stressed and anxious mindfulness for many*, but mindfulness nonetheless.
*which is why “mindfulness-based stress reduction” is not a redundant tautology repeated more than once unnecessarily, one time after another 😉
So: do try to keep aware of what you are doing to your skin, and so far as is reasonably practicable, only do the things that are good for it!
The skin as an endocrine organ
Nerves are not the only messengers in the body; hormones do a lot of our body’s internal communication too. And not just the ones everyone remembers are hormones (e.g. estrogen, testosterone, although yes, they do both have a big impact on skin too), but also many more, including some made in the skin itself!
Dr. Aguirra gives us a rundown of common conditions, the hormones behind them, and what we can do if we don’t want them:
Read more: Rethinking The Skin As An Endocrine Organ
Take-away advice:
For healthy skin, we need to do more than just hydrate, get good sleep, have good nutrition, and get a little sun (but not too much).
- We should also practice mindfulness-based stress reduction, and seek help for more serious mental health issues.
- We should also remember the part our hormones play in our skin, and not just the obvious ones.
Did you know that vitamin D is also a hormone, by the way? It’s not the only hormone at play in your skin by a long way, but it is an important one:
Society for Endocrinology | Vitamin D
Want to know more?
You might like this interview with Dr. Aguirre:
The Brain in Our Skin: An Interview with Dr. Claudia Aguirre
Take care!
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Menopause: 50 Things You Need to Know – by Dr. Felice Gersh
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Can you list 50 important facts about the menopause? If not, you’ll surely find things to learn in here.
The book is divided into three main sections:
- What to expect in perimenopause
- What to expect in early menopause
- What to expect in late menopause
Each section comes with an alarming array of symptoms, ranging from perimenopause fatigue and acne to late menopause tooth loss and vaginal prolapse. This is not to say that everyone will experience everything (fortunately), but rather, that these are the things that can happen and should not arrive unexpected.
Helpfully, of course, Dr. Gersh also gives advice on how to improve your energy and skin health, as well as keep your teeth and vagina in place. And similar professional insights for the rest of the “50 things you need to know”.
The style is like one big (182 pages) patient information leaflet—thus, very clear, explaining everything, and offering reassurance where possible and also what things are reasonable cause for seeking personalized medical attention.
Bottom line: if menopause is in your future, present, or very near past, this is an excellent book for you.
Click here to check out Menopause: 50 Things You Need To Know, and know them!
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The Bare-Bones Truth About Osteoporosis
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In yesterday’s issue of 10almonds, we asked you “at what age do you think it’s important to start worrying about osteoporosis?”, and here’s the spread of answers you gave us:
The Bare-bones Truth About Osteoporosis
In yesterday’s issue of 10almonds, we asked you “at what age do you think it’s important to start worrying about osteoporosis?”, and here’s the spread of answers you gave us:
At first glance it may seem shocking that a majority of respondents to a poll in a health-focused newsletter think it’ll never be an issue worth worrying about, but in fact this is partly a statistical quirk, because the vote of the strongest “early prevention” crowd was divided between “as a child” and “as a young adult”.
This poll also gave you the option to add a comment with your vote. Many subscribers chose to do so, explaining your choices… But, interestingly, not one single person who voted for “never” had any additional thoughts to add.
We loved reading your replies, by the way, and wish we had room to include them here, because they were very interesting and thought-provoking.
Let’s get to the myths and facts:
Top myth: “you will never need to worry about it; drink a glass of milk and you’ll be fine!”
The body is constantly repairing itself. Its ability to do that declines with age. Until about 35 on average, we can replace bone mineral as quickly as it is lost. After that, we lose it by up to 1% per year, and that rate climbs after 50, and climbs even more steeply for those who go through (untreated) menopause.
Losing 1% per year might not seem like a lot, but if you want to live to 100, there are some unfortunate implications!
About that menopause, by the way… Because declining estrogen levels late in life contribute significantly to osteoporosis, hormone replacement therapy (HRT) may be of value to many for the sake of bone health, never mind the more obvious and commonly-sought benefits.
On the topic of that glass of milk…
- Milk is a great source of calcium, which is useless to the body if you don’t also have good levels of vitamin D and magnesium.
- People’s vitamin D levels tend to directly correlate to the level of sun where they live, if supplementation isn’t undertaken.
- Plant-based milks are usually fortified with vitamin D (and calcium), by the way.
- Most people are deficient in magnesium, because green leafy things don’t form as big a part of most people’s diets as they should.
See also: An update on magnesium and bone health
Next most common myth: “bone health is all about calcium”
We spoke a little above about the importance of vitamin D and magnesium for being able to properly use that. But potassium is also critical:
Read more: The effects of potassium on bone health
While we’re on the topic…
People think of collagen as being for skin health. And it is important for that, but collagen’s benefits (and the negative effects of its absence) go much deeper, to include bone health. We’ve written about this before, so rather than take more space today, we’ll just drop the link:
We Are Such Stuff As Fish Are Made Of
Want to really maximize your bone health?
You might want to check out this well-sourced LiveStrong article:
Bone Health: Best and Worst Foods
(Teaser: leafy greens are in 2nd place, topped by sardines at #1—where do you think milk ranks?)
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Managing Jealousy
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Jealousy is often thought of as a young people’s affliction, but it can affect us at any age—whether we are the one being jealous, or perhaps a partner.
And, the “green-eyed monster” can really ruin a lot of things; relationships, friendships, general happiness, physical health even (per stress and anxiety and bad sleep), and more.
The thing is, jealousy looks like one thing, but is actually mostly another.
Jealousy is a Scooby-Doo villain
That is to say: we can unmask it and see what much less threatening thing is underneath. Which is usually nothing more nor less than: insecurities
- Insecurity about losing one’s partner
- Insecurity about not being good enough
- Insecurity about looking bad socially
…etc. The latter, by the way, is usually the case when one’s partner is socially considered to be giving cause for jealousy, but the primary concern is not actually relational loss or any kind of infidelity, but rather, looking like one cannot keep one’s partner’s full attention romantically/sexually. This drives a lot of people to act on jealousy for the sake of appearances, in situations where they might otherwise, if they didn’t feel like they’d be adversely judged for it, be considerably more chill.
Thus, while monogamy certainly has its fine merits, there can also be a kind of “toxic monogamy” at hand, where a relationship becomes unhealthy because one partner is just trying to live up to social expectations of keeping the other partner in check.
This, by the way, is something that people in polyamorous and/or open relationships typically handle quite neatly, even if a lot of the following still applies. But today, we’re making the statistically safe assumption of a monogamous relationship, and talking about that!
How to deal with the social aspect
If you sit down with your partner and work out in advance the acceptable parameters of your relationship, you’ll be ahead of most people already. For example…
- What counts as cheating? Is it all and any sex acts with all and any people? If not, where’s the line?
- What about kissing? What about touching other body parts? If there are boundaries that are important to you, talk about them. Nothing is “too obvious” because it’s astonishing how many times it will happen that later someone says (in good faith or not), “but I thought…”
- What about being seen in various states of undress? Or seeing other people in various states of undress?
- Is meaningless flirting between friends ok, and if so, how do we draw the line with regard to what is meaningless? And how are we defining flirting, for that matter? Talk about it and ensure you are both on the same page.
- If a third party is possibly making moves on one of us under the guise of “just being friendly”, where and how do we draw the line between friendliness and romantic/sexual advances? What’s the difference between a lunch date with a friend and a romantic meal out for two, and how can we define the difference in a way that doesn’t rely on subjective “well I didn’t think it was romantic”?
If all this seems like a lot of work, please bear in mind, it’s a lot more fun to cover this cheerfully as a fun couple exercise in advance, than it is to argue about it after the fact!
See also: Boundary-Setting Beyond “No”
How to deal with the more intrinsic insecurities
For example, when jealousy is a sign of a partner fearing not being good enough, not measuring up, or perhaps even losing their partner.
The key here might not shock you: communication
Specifically, reassurance. But critically, the correct reassurance!
A partner who is jealous will often seek the wrong reassurance, for example wanting to read their partner’s messages on their phone, or things like that. And while a natural desire when experiencing jealousy, it’s not actually helpful. Because while incriminating messages could confirm infidelity, it’s impossible to prove a negative, and if nothing incriminating is found, the jealous partner can just go on fearing the worst regardless. After all, their partner could have a burner phone somewhere, or a hidden app for cheating, or something else like that. So, no reassurance can ever be given/gained by such requests (which can also become unpleasantly controlling, which hopefully nobody wants).
A quick note on “if you have nothing to fear, you have nothing to hide”: rhetorically that works, but practically it doesn’t.
Writer’s example: when my late partner and I formalized our relationship, we discussed boundaries, and I expressed “so far as I am concerned, I have no secrets from you, except secrets that are not mine to share. For example, if someone has confided in me and asked that I not share it, I won’t. Aside from that, you have access-all-areas in my life; me being yours has its privileges” and this policy itself would already pre-empt any desire to read my messages.
Now indeed, I had nothing to hide. I am by character devoted to a fault. But my friends may well sometimes have things they don’t want me to share, which made that a necessary boundary to highlight (which my partner, an absolute angel by the way and not prone to unhealthy manifestations of jealousy in any case, understood completely).
So, it is best if the partner of a jealous person can explain the above principles as necessary, and offer the correct reassurance instead. Which could be any number of things, but for example:
- I am yours, and nobody else has a chance
- I fully intend to stay with you for life
- You are the best partner I have ever had
- Being with you makes my life so much better
…etc. Note that none of these are “you don’t have to worry about so-and-so”, or “I am not cheating on you”, etc, because it’s about yours and your partner’s relationship. If they ask for reassurances with regard to other people or activities, by all means state them as appropriate, but try to keep the focus on you two.
And if your partner (or you, if it’s you who’s jealous) can express the insecurity in the format…
“I’m afraid of _____ because _____”
…then the “because” will allow for much more specific reassurance. We all have insecurities, we all have reasons we might fear not being good enough for our partner, or losing their affection, and the best thing we can do is choose to trust our partners at least enough to discuss those fears openly with each other.
See also: Save Time With Better Communication ← this can avoid a lot of time-consuming arguments
What about if the insecurity is based in something demonstrably correct?
By this we mean, something like a prior history of cheating, or other reasons for trust issues. In such a case, the jealous partner may well have a reason for their jealousy that isn’t based on a personal insecurity.
In our previous article about boundaries, we talked about relationships (romantic or otherwise) having a “price of entry”. In this case, you each have a “price of entry”:
- The “price of entry” to being with the person who has previously cheated (or similar), is being able to accept that.
- And for the person who cheated (or similar), very likely their partner will have the “price of entry” of “don’t do that again, and also meanwhile accept in good grace that I might be jittery about it”.
And, if the betrayal of trust was something that happened between the current partners in the current relationship, most likely that was also traumatic for the person whose trust was betrayed. Many people in that situation find that trust can indeed be rebuilt, but slowly, and the pain itself may also need treatment (such as therapy and/or couples therapy specifically).
See also: Relationships: When To Stick It Out & When To Call It Quits ← this covers both sides
And finally, to finish on a happy note:
Only One Kind Of Relationship Promotes Longevity This Much!
Take care!
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