From straight to curly, thick to thin: here’s how hormones and chemotherapy can change your hair

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Head hair comes in many colours, shapes and sizes, and hairstyles are often an expression of personal style or cultural identity.

Many different genes determine our hair texture, thickness and colour. But some people’s hair changes around the time of puberty, pregnancy or after chemotherapy.

So, what can cause hair to become curlier, thicker, thinner or grey?

Curly or straight? How hair follicle shape plays a role

Hair is made of keratin, a strong and insoluble protein. Each hair strand grows from its own hair follicle that extends deep into the skin.

Curly hair forms due to asymmetry of both the hair follicle and the keratin in the hair.

Follicles that produce curly hair are asymmetrical and curved and lie at an angle to the surface of the skin. This kinks the hair as it first grows.

The asymmetry of the hair follicle also causes the keratin to bunch up on one side of the hair strand. This pulls parts of the hair strand closer together into a curl, which maintains the curl as the hair continues to grow.

Follicles that are symmetrical, round and perpendicular to the skin surface produce straight hair.

A diagram shows the hair follicle shape of straight, curly and coiled hair.
Each hair strand grows from its own hair follicle.
Mosterpiece/Shutterstock

Life changes, hair changes

Our hair undergoes repeated cycles throughout life, with different stages of growth and loss.

Each hair follicle contains stem cells, which multiply and grow into a hair strand.

Head hairs spend most of their time in the growth phase, which can last for several years. This is why head hair can grow so long.

Let’s look at the life of a single hair strand. After the growth phase is a transitional phase of about two weeks, where the hair strand stops growing. This is followed by a resting phase where the hair remains in the follicle for a few months before it naturally falls out.

The hair follicle remains in the skin and the stems cells grow a new hair to repeat the cycle.

Each hair on the scalp is replaced every three to five years.

A woman with curly hair works on her computer.
Each hair on the scalp is replaced every three to five years.
Just Life/Shutterstock

Hormone changes during and after pregnancy alter the usual hair cycle

Many women notice their hair is thicker during pregnancy.

During pregnancy, high levels of oestrogen, progesterone and prolactin prolong the resting phase of the hair cycle. This means the hair stays in the hair follicle for longer, with less hair loss.

A drop in hormones a few months after delivery causes increased hair loss. This is due to all the hairs that remained in the resting phase during pregnancy falling out in a fairly synchronised way.

Hair can change around puberty, pregnancy or after chemotherapy

This is related to the genetics of hair shape, which is an example of incomplete dominance.

Incomplete dominance is when there is a middle version of a trait. For hair, we have curly hair and straight hair genes. But when someone has one curly hair gene and one straight hair gene, they can have wavy hair.

Hormonal changes that occur around puberty and pregnancy can affect the function of genes. This can cause the curly hair gene of someone with wavy hair to become more active. This can change their hair from wavy to curly.

Researchers have identified that activating specific genes can change hair in pigs from straight to curly.

Chemotherapy has very visible effects on hair. Chemotherapy kills rapidly dividing cells, including hair follicles, which causes hair loss. Chemotherapy can also have genetic effects that influence hair follicle shape. This can cause hair to regrow with a different shape for the first few cycles of hair regrowth.

A woman with wavy hair looks in a mirror
Your hair can change at different stages of your life.
Igor Ivakhno/Shutterstock

Hormonal changes as we age also affect our hair

Throughout life, thyroid hormones are essential for production of keratin. Low levels of thyroid hormones can cause dry and brittle hair.

Oestrogen and androgens also regulate hair growth and loss, particularly as we age.

Balding in males is due to higher levels of androgens. In particular, high dihydrotestosterone (sometimes shortened to DHT), which is produced in the body from testosterone, has a role in male pattern baldness.

Some women experience female pattern hair loss. This is caused by a combination of genetic factors plus lower levels of oestrogen and higher androgens after menopause. The hair follicles become smaller and smaller until they no longer produce hairs.

Reduced function of the cells that produce melanin (the pigment that gives our hair colour) is what causes greying.The Conversation

Theresa Larkin, Associate professor of Medical Sciences, University of Wollongong

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

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  • Is it OK to lie to someone with dementia?

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    There was disagreement on social media recently after a story was published about an aged care provider creating “fake-away” burgers that mimicked those from a fast-food chain, to a resident living with dementia. The man had such strict food preferences he was refusing to eat anything at meals except a burger from the franchise. This dementia symptom risks malnutrition and social isolation.

    But critics of the fake burger approach labelled it trickery and deception of a vulnerable person with cognitive impairment.

    Dementia is an illness that progressively robs us of memories. Although it has many forms, it is typical for short-term recall – the memory of something that happened in recent hours or days – to be lost first. As the illness progresses, people may come to increasingly “live in the past”, as distant recall gradually becomes the only memories accessible to the person. So a person in the middle or later stages of the disease may relate to the world as it once was, not how it is today.

    This can make ethical care very challenging.

    Pikselstock/Shutterstock

    Is it wrong to lie?

    Ethical approaches classically hold that specific actions are moral certainties, regardless of the consequences. In line with this moral absolutism, it is always wrong to lie.

    But this ethical approach would require an elderly woman with dementia who continually approaches care staff looking for their long-deceased spouse to be informed their husband has passed – the objective truth.

    Distress is the likely outcome, possibly accompanied by behavioural disturbance that could endanger the person or others. The person’s memory has regressed to a point earlier in their life, when their partner was still alive. To inform such a person of the death of their spouse, however gently, is to traumatise them.

    And with the memory of what they have just been told likely to quickly fade, and the questioning may resume soon after. If the truth is offered again, the cycle of re-traumatisation continues.

    older man looks into distance holding mug
    People with dementia may lose short term memories and rely on the past for a sense of the world. Bonsales/Shutterstock

    A different approach

    Most laws are examples of absolutist ethics. One must obey the law at all times. Driving above the speed limit is likely to result in punishment regardless of whether one is in a hurry to pick their child up from kindergarten or not.

    Pragmatic ethics rejects the notion certain acts are always morally right or wrong. Instead, acts are evaluated in terms of their “usefulness” and social benefit, humanity, compassion or intent.

    The Aged Care Act is a set of laws intended to guide the actions of aged care providers. It says, for example, psychotropic drugs (medications that affect mind and mood) should be the “last resort” in managing the behaviours and psychological symptoms of dementia.

    Instead, “best practice” involves preventing behaviour before it occurs. If one can reasonably foresee a caregiver action is likely to result in behavioural disturbance, it flies in the face of best practice.

    What to say when you can’t avoid a lie?

    What then, becomes the best response when approached by the lady looking for her husband?

    Gentle inquiries may help uncover an underlying emotional need, and point caregivers in the right direction to meet that need. Perhaps she is feeling lonely or anxious and has become focused on her husband’s whereabouts? A skilled caregiver might tailor their response, connect with her, perhaps reminisce, and providing a sense of comfort in the process.

    This approach aligns with Dementia Australia guidance that carers or loved ones can use four prompts in such scenarios:

    • acknowledge concern (“I can tell you’d like him to be here.”)
    • suggest an alternative (“He can’t visit right now.”)
    • provide reassurance (“I’m here and lots of people care about you.”)
    • redirect focus (“Perhaps a walk outside or a cup of tea?”)

    These things may or may not work. So, in the face of repeated questions and escalating distress, a mistruth, such as “Don’t worry, he’ll be back soon,” may be the most humane response in the circumstances.

    Different realities

    It is often said you can never win an argument with a person living with dementia. A lot of time, different realities are being discussed.

    So, providing someone who has dementia with a “pretend” burger may well satisfy their preferences, bring joy, mitigate the risk of malnutrition, improve social engagement, and prevent a behavioural disturbance without the use of medication. This seems like the correct approach in ethical terms. On occasion, the end justifies the means.

    Steve Macfarlane, Head of Clinical Services, Dementia Support Australia, & Associate Professor of Psychiatry, Monash University

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

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  • 16 Overlooked Autistic Traits In Women

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    We hear a lot about “autism moms”, but Taylor Heaton is an autistic mom, diagnosed as an adult, and she has insights to share about overlooked autistic traits in women.

    The Traits

    • Difficulty navigating romantic relationships: often due to misreading signs
    • Difficulty understanding things: including the above, but mostly: difficulty understanding subtext, when people leave things as “surely obvious”. Autistic women are likely to be aware of the possible meanings, but unsure which it might be, and may well guess wrongly.
    • Masking: one of the reasons for the gender disparity in diagnosis is that autistic women are often better at “masking”, that is to say, making a conscious effort to blend in to allistic society—often as a result of being more societally pressured to do so.
    • Honesty: often to a fault
    • Copy and paste: related to masking, this is about consciously mirroring others in an effort to put them at ease and be accepted
    • Being labelled sensitive and/or gifted: usually this comes at a young age, but the resultant different treatment can have a lifetime effect
    • Secret stims: again related to masking, and again for the same reasons that displaying autistic symptoms is often treated worse in women, autistic women’s stims tend to be more subtle.
    • Written communication: autistic women are often more comfortable with the written word than the spoken
    • Leadership: autistic women will often gravitate to leadership roles, partly as a survival mechanism
    • Gaslighting: oneself, e.g. “If this person did this without that, then I can to” (without taking into account that maybe the circumstances are different, or maybe they actually did lean on crutches that you didn’t know were there, etc).
    • Inner dialogue: rich inner dialogue, but unable to express it outwardly—often because of the sheer volume of thoughts per second.
    • Fewer female friends: often few friends overall, for that matter, but there’s often a gender imbalance towards male friends, or where there isn’t, towards more masculine friends at least.
    • Feeling different: often a matter of feeling one does not meet standard expectations in some fashion
    • School: autistic women are often academically successful
    • Special interests: often more “socially accepted” interests than autistic men’s.
    • Flirting: autistic women are often unsure how to flirt or what to do about it, which can result in simple directness instead

    For more details on all of these, enjoy:

    Click Here If The Embedded Video Doesn’t Load Automatically!

    Related reading:

    You might like a main feature of ours from not long back:

    Miss Diagnosis: Anxiety, ADHD, & Women

    Take care!

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  • Managing [E-word] Dysfunction Reactions

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    It’s Q&A Day at 10almonds!

    Have a question or a request? You can always hit “reply” to any of our emails, or use the feedback widget at the bottom!

    In cases where we’ve already covered something, we might link to what we wrote before, but will always be happy to revisit any of our topics again in the future too—there’s always more to say!

    As ever: if the question/request can be answered briefly, we’ll do it here in our Q&A Thursday edition. If not, we’ll make a main feature of it shortly afterwards!

    So, no question/request too big or small

    We had several requests pertaining to veganism, meatless mondays, and substitutions in recipes—so we’re going to cover those on a different day!

    As for questions we’re answering today…

    Q: Information on [e-word] dysfunction for those who have negative reactions to [the most common medications]?

    When it comes to that particular issue, one or more of these three factors are often involved:

    • Hormones
    • Circulation
    • Psychology

    The most common drugs (that we can’t name here) work on the circulation side of things—specifically, by increasing the localized blood pressure. The exact mechanism of this drug action is interesting, albeit beyond the scope of a quick answer here today. On the other hand, the way that they work can cause adverse blood-pressure-related side effects for some people; perhaps you’re one of them.

    To take matters into your own hands, so to speak, you can address each of those three things we just mentioned:

    Hormones

    Ask your doctor (or a reputable phlebotomy service) for a hormone test. If your free/serum testosterone levels are low (which becomes increasingly common in men over the age of 45), they may prescribe something—such as testosterone shots—specifically for that.

    This way, it treats the underlying cause, rather than offering a workaround like those common pills whose names we can’t mention here.

    Circulation

    Look after your heart health; eat for your heart health, and exercise regularly!

    Cold showers/baths also work wonders for vascular tone—which is precisely what you need in this matter. By rapidly changing temperatures (such as by turning off the hot water for the last couple of minutes of your shower, or by plunging into a cold bath), your blood vessels will get practice at constricting and maintaining that constriction as necessary.

    Psychology

    [E-word] dysfunction can also have a psychological basis. Unfortunately, this can also then be self-reinforcing, if recalling previous difficulties causes you to get distracted/insecure and lose the moment. One of the best things you can do to get out of this catch-22 situation is to not worry about it in the moment. Depending on what you and your partner(s) like to do in bed, there are plenty of other equally respectable options, so just switch track!

    Having a conversation about this in advance will probably be helpful, so that everyone’s on the same page of the script in that eventuality, and it becomes “no big deal”. Without that conversation, misunderstandings and insecurities could arise for your partner(s) as well as yourself (“aren’t I desirable enough?” etc).

    So, to recap, we recommend:

    • Have your hormones checked
    • Look after your circulation
    • Make the decision to have fun!

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  • Uric Acid’s Extensive Health Impact (And How To Lower It)

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    Uric Acid’s Extensive Health Impact (And How To Lower It)

    This is Dr. David Perlmutter. He’s a medical doctor, and a Fellow of the American College of Nutrition. He’s a member of the Editorial Board for the Journal of Alzheimer’s Disease, and has been widely published in many other peer-reviewed journals.

    What does he want us to know?

    He wants us to know about the health risks of uric acid (not something popularly talked about so much!), and how to reduce it.

    First: what is it? Uric acid is a substance we make in our own body. However, unlike most substances we make in our body, we have negligible use for it—it’s largely a waste product, usually excreted in urine.

    However, if we get too much, it can build up (and crystallize), becoming such things as kidney stones, or causing painful inflammation if it shows up in the joints, as in gout.

    More seriously (unpleasant as kidney stones and gout may be), this inflammation can have a knock-on effect triggering (or worsening) other inflammatory conditions, ranging from non-alcoholic fatty liver disease, to arthritis, to dementia, and even heart problems. See for example:

    How can we reduce our uric acid levels?

    Uric acid is produced when we metabolize purine nucleotides, which are found in many kinds of food. We can therefore reduce our uric acid levels by reducing our purine intake, as well as things that mess up our liver’s ability to detoxify things. Offsetting the values for confounding variables (such as fiber content, or phytochemicals that mitigate the harm), the worst offenders include…

    Liver-debilitating things:

    • Alcohol (especially beer)
    • High-fructose corn syrup (and other fructose-containing things that aren’t actual fruit)
    • Other refined sugars
    • Wheat / white flour products (this is why beer is worse than wine, for example; it’s a double-vector hit)

    Purine-rich things:

    • Red meats and game
    • Organ meats
    • Oily fish, and seafood (great for some things; not great for this)

    Some beans and legumes are also high in purines, but much like real fruit has a neutral or positive effect on blood sugar health despite its fructose content, the beans and legumes that are high in purines, also contain phytochemicals that help lower uric acid levels, so have a beneficial effect.

    Eggs (consumed in moderation) and tart cherries have a uric-acid lowering effect.

    Water is important for all aspects of health, and doubly important for this.

    Hydrate well!

    Lifestyle matters beyond diet

    The main key here is metabolic health, so Dr. Perlmutter advises the uncontroversial lifestyle choices of moderate exercise and good sleep, as well as (more critically) intermittent fasting. We wrote previously on other things that can benefit liver health:

    How To Unfatty A Fatty Liver

    …in this case, that means the liver gets a break to recuperate (something it’s very good at, but does need to get a chance to do), which means that while you’re not giving it something new to do, it can quickly catch up on any backlog, and then tackle any new things fresh, next time you start eating.

    Want to know more about this from Dr. Perlmutter?

    You might like his article:

    An Integrated Plan for Lowering Uric Acid ← more than we had room for here; he also talks about extra things to include in your diet/supplementation regime for beneficial effects!

    And/or his book:

    Drop Acid: The Surprising New Science of Uric Acid―The Key to Losing Weight, Controlling Blood Sugar, and Achieving Extraordinary Health

    …on which much of today’s main feature was based.

    Take care!

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  • How Much Alcohol Does It Take To Increase Cancer Risk?

    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.

    Alcohol is, of course, unhealthy. Not even the famous “small glass of red” is recommended:

    Can We Drink To Good Health?

    Alcohol also increases all-cause mortality at any dose (even “low-risk drinking”):

    Alcohol Consumption Patterns and Mortality Among Older Adults

    …and the World Health Organization has declared that the only safe amount of alcohol is zero:

    WHO: No level of alcohol consumption is safe for our health

    But what of alcohol and cancer? According to the American Association of Cancer Research’s latest report, more than half of Americans do not know that alcohol increases the risk of cancer:

    Source: AACR Cancer Progress Report

    Why/how does alcohol increase the risk of cancer?

    There’s an obvious aspect and a less obvious but very important aspect:

    • The obvious: alcohol damages almost every system in the body, and so it’s little surprise if that includes systems whose job it is to keep us safe from cancer.
    • The less obvious: alcohol is largely metabolized by certain enzymes that have an impact on DNA repair, such as alcohol dehydrogenases and aldehyde dehydrogenases, amongst others, and noteworthily, acetaldehyde (the main metabolite of alcohol) is itself genotoxic.

    Read more: Alcohol & Cancer

    This is important, because it means alcohol also increases the risk of cancers other than the obvious head/neck, laryngeal, esophageal, liver, and colorectal cancers.

    However, those cancers are of course the most well-represented of alcohol-related cancers, along with breast cancer (this has to do with alcohol’s effect on estrogen metabolism).

    If you’re curious about the numbers, and the changes in risk if one reduces/quits/reprises drinking:

    ❝The increased alcohol-related cancer incidence was associated with dose; those who changed from nondrinking to mild (adjusted hazard ratio [aHR], 1.03; 95% CI, 1.00-1.06), moderate (aHR, 1.10; 95% CI, 1.02-1.18), or heavy (aHR, 1.34; 95% CI, 1.23-1.45) drinking levels had an associated higher risk than those who did not drink.

    Those with mild drinking levels who quit drinking had a lower risk of alcohol-related cancer (aHR, 0.96; 95% CI, 0.92-0.99) than those who sustained their drinking levels.

    Those with moderate (aHR, 1.07; 95% CI, 1.03-1.12) or heavy (aHR, 1.07; 95% CI, 1.02-1.12) drinking levels who quit drinking had a higher all cancer incidence than those who sustained their levels, but when quitting was sustained, this increase in risk disappeared.

    Results of this study showed that increased alcohol consumption was associated with higher risks for alcohol-related and all cancers, whereas sustained quitting and reduced drinking were associated with lower risks of alcohol-related and all cancers.

    Alcohol cessation and reduction should be reinforced for the prevention of cancer.❞

    Source: Association Between Changes in Alcohol Consumption and Cancer Risk

    Worried it’s too late?

    If you’re reading this (and thus, evidently, still alive), it isn’t. It’s never too late (nor too early) to reduce, or ideally stop, drinking. Even if you already have cancer, drinking more alcohol will only exacerbate things, and abstaining from alcohol will improve your chances of recovery.

    For a reassuring timeline of recovery from alcohol-related damage, see:

    What Happens To Your Body When You Stop Drinking Alcohol

    Want to stop, but have tried before and find it daunting?

    There are a few ways to make it a lot easier:

    Rethinking Drinking: How To Reduce Or Quit Alcohol

    Take care!

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  • The 5 Resets – by Dr. Aditi Nerurkar

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    What this book isn’t: an advice to go on a relaxing meditation retreat, or something like that.

    What this is: a science-based guide to what actually works.

    There’s no need to be mysterious, so we’ll mention that the titular “5 resets” are:

    1. What matters most
    2. Quiet in a noisy world
    3. Leveraging the brain-body connection
    4. Coming up for air (regaining perspective)
    5. Bringing your best self forward

    All of these are things we can easily lose sight of in the hustle and bustle of daily life, so having a system for keeping them on track can make a huge difference!

    The style is personable and accessible, while providing a lot of strongly science-backed tips and tricks along the way.

    Bottom line: if life gets away from you a little too often for comfort, this book can help you keep on top of things with a lot less stress.

    Click here to check out “The 5 Resets”, and take control with conscious calm!

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