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How light helped shape the color of our skin, eyes and curly hair

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For most of our evolutionary history, human activity has been linked to sunlight. Technology has liberated us from these ancient sleep-wake cycles, but there’s evidence that sunlight has left and continues to go away its traces.

Not only are we still awake during the day, but we sleep at night, we will thank light for a lot of other facets of our biology.

Light could have made our ancestors walk upright on two legs. Light helps explain the evolution of our skin color, why some of us have curly hair, and even the size of our eyes.

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As we’ll learn in future articles on this series, light helps shape our mood, our immune system, our gut function, and way more. Light could make us sick, tell us why we’re sick, and then heal us.

Millions of years of evolutionary history mean that humans are still largely creatures of light.

We got up and left Africa

The first modern humans evolved in the warm African climate. And reducing exposure to brilliant sunlight Is one explanation why people began walking upright, on two legs. When we stand up and the Sun is directly above us, much less sunlight reaches our body.

They also can have curly hair he protected us from the hot sun. The idea is that it provides a thicker layer of insulation than straight hair to guard the scalp.

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Early had additional sun protection in the form of highly pigmented skin. Sunlight breaks down folic acid (vitamin B9), accelerates aging and damages DNA. In our light ancestral climates, dark skin was protected against this. But this dark skin still confessed enough UV light to stimulate the obligatory production of vitamin D.

However, as humans colonized temperate zones with lower light, this occurred lighter skin has evolved again and againthrough different genes in several populations. This happened quickly, probably inside the last 40,000 years.

With reduced UV radiation closer to the poles, less pigmentation was needed to guard sunlight from breaking down folic acid. Lighter skin also let in additional thin light, allowing the body to provide vitamin D. But there was one big drawback: less pigmentation meant less protection against sun damage.

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How our skin’s pigmentation adapts to migration patterns and changing light.

This evolutionary background is why Australia has one of the highest rates of skin cancer in the world.

Our colonial history signifies that over 50% of Australians are of Anglo-Celtic descent, have fair skin and are transplanted to an environment with high levels of UV radiation. No wonder we’re described as “a rustic scorched by the sun“.

Sunlight has also contributed to changes in human eyes. People living in high latitudes have less protective pigment of their irises. They have too larger eye sockets (and probably eyeballs), perhaps let in the more precious light.

Again, these characteristics make Australians of European descent particularly liable to our harsh light. So it’s no surprise that Australia has this unusual thing high rate of eye cancer.

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We cannot move our biological clock

Our circadian rhythm – the wake-sleep cycle driven by our brains and hormones – is one other piece of heavy evolutionary baggage triggered by light.

Humans are adapted to sunlight. In the brilliant light people can see well and improved it color vision. But we see poorly in dim light, and we lack senses like acute hearing or acute smell to make up for it.

Our closest relatives (chimpanzees, gorillas, and orangutans) are also lively during the day and sleep at night, supporting the concept that early humans exhibited similar daytime behaviors.

This lifestyle probably goes back further in our evolutionary history, before the appearance of great apes, to the origins of primates.

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The earliest mammals were generally nocturnal, using their small size and cover of darkness to cover from dinosaurs. However, the meteorite impact that worn out these fearsome reptiles allowed some surviving mammals, especially primates, to largely evolve each day lifestyle.

If we inherited our daylight activity pattern directly from these early primates, then this rhythm would have been part of the evolutionary history of our lineage for nearly 66 million years.

This explains why it is vitally difficult to maneuver our 24-hour clock; it’s so deeply rooted in our evolutionary history.

Next improvements in lighting technology they freed us more and more from our dependence on daylight: fire, candles, kerosene and gas lamps, and finally electric lighting. So theoretically we will work and play at any time.

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However, our cognitive and physical performance deteriorates when our internal circadian cycles are disruptedfor instance, because of lack of sleep, shift work or jet lag.

Futurists have already considered the required circadian rhythms life on Mars. Fortunately, a day on Mars lasts about 24.7 hours, which is analogous to ours. This slight difference must have been the least of the worries of the first intrepid Martian colonists.

How would humans cope on Mars? At least they would not should worry an excessive amount of about their biological clock.
NikoNomada/NASA/Shutterstock

The light continues to alter us

Over the last 200 years, artificial lighting has helped (partially) disconnect us from the circadian rhythms of our ancestors. However, in recent many years this has come at the expense of our eyesight.

Many genes are related to myopia (nearsightedness). develop into more common in only 25 years, a striking example of rapid evolutionary change in the human gene pool.

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And if you’ve a genetic predisposition to myopia, reduced exposure to natural light (and spending more time in artificial light) increases your likelihood of developing myopia. These noticeable changes have occurred over the course of many individuals’s lives.

Light will undoubtedly proceed to shape our biology for millennia to return, but the long-term effects could also be difficult to predict.

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This article was originally published on : theconversation.com
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Health and Wellness

Supporters call FDA to prohibit formaldehyde in hair products

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FORMALDEHYDE,relaxer, hair, Back women, straightener


A gaggle of environmental and public health protection organization has united to write an open letter to the American Food and Drug Agency (FDA), calling for immediate prohibition of formaldehyde in hair suppression products.

A letter of April 15, developed in cooperation between women’s voices for Earth (WVE) and 41 environmental organizations and public health throughout the country, calls on the newly confirmed FDA Commissioner, Dr. Marta Makary to act after years of stopping progress and omitting deadlines.

“Repeated FDA failures to implement a formaldehyde prohibition in hair straightening products reflect the wider problem of regulatory inertia, which threatens our health”, programs director Jayla Burton programs he said in a press release. “Regulatory authorities still cannot sideways for bureaucratic delays and budget cuts. Time for action is now.”

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Supporters called on the FDA to examine the threats to formaldehyde in hair -entertaining products and smoothing treatments. Dangerous carcinogens expose the workers of salons and consumers to the chance of cancer, respiratory complications and severe allergic reactions. Especially hairdressers who serve black and Latin women who’ve recent studies show an increased exposure to toxic LZO in chemical hair products, exposing their serious health.

The open letter is the newest WVE step to support the formaldehyde ban. It comes almost 10 years after the organization took the FDA to court in 2016 for ignoring a six -year petition calling on the agency to examine the health threats related to formaldehyde in hair products. While the FDA made the guarantees of taking motion in April 2024, the agency has postponed its proposed date of operation 4 times, with the newest in March 2025.

The longer the delay, the more the health of salon and consumers employees is in danger. But since the FDA has recently released almost 3,500 FDA employees, delays in critical matters are still unsatisfied.

“Black and brown women have long been borne by the burden of toxic beauty standards and products that are associated with them. A continuous delay in prohibiting formaldehyde – a known carcinogenic factor – this is not only regulatory failure, it is injustice of public health,” said Diamond Spratling, founder and executive director of Girl Plus Environment. “We call the FDA to the priority of life, health and dignity of the most affecting and rapid movement to prohibit formaldehyde in hair suppression products.”

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(Tagstranslat) voices of girls for Earth

This article was originally published on : www.blackenterprise.com
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Why midwives matter – and what most people commit in them

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Myqueen “Nurse Queen” Dickens, MSN, CNMHe has a mission to set a record about midwives – and raising black people in this process.

As a nurse from DMV, she recently visited the headquarters of Black Girl Magic to speak in regards to the locations: what midwives do, how they differ from Dous and why their care model is especially essential for black moms and future parents.

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While some still confuse midwives from Dous, the role of the midwife is evident – and removed from the brand new one. A midwife practice, which concentrates the holistic care led by patients, comes from precedent days. But because medicine has grow to be more institutionalized, childbirth transferred from home to the hospital, and the face of maternity care has grow to be more and more male and clinical. Not to say that deliveries have grow to be more surgical than natural with the growing birth of the imperial.

Still, midwives never left. Known for contributing to higher results, corresponding to lower indicators of section C, more rare complications and a more satisfied mother, midwives experience a powerful revival.

In honor of the Black Health Week of Mother, Dickens shares what every present or future parent should learn about this basic type of care and reminds people born by people about their power, decisions and support they deserve day by day of the yr.

Why midwives matter - and what most people commit in them
Micheal Kirby Jr.

Essence: Can you tell us why the Black Week of Mother’s Health, above all, is so essential? Knowing the whole lot that happens and the whole lot that black women are coping with when they struggle to offer birth?

Queen of nurse: I believe that generally the mother’s black health may be very essential because black women deserve beautiful delivery stories. Often, women die and die because they are usually not heard. Because they are usually not advisable. So I do know that the black maternal health, staff give birth to actually enter the image and change this narrative about what birth stories seem like. So black women and black families can live.

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How did you realize that being a midwife was your calling?

When I used to be younger, I desired to be Ob-Gyn. I desired to grow to be a physician, so I went the best way. My mother is Jamaican, so I had just a few decisions: a nurse, a physician or lawyer. So I went to nursing, and then began childbirth and delivery. I loved it. And I went through to get a master’s degree in nursing, which led me to becoming a licensed midwife. So I even have a master’s degree in nursing as a licensed midwife. But I really like all born things, I really like all things, women’s health, baby health, and I really like black women, so being a part of their experience of birth and pregnancy may be very essential to me.

I find it irresistible. Can you in a way check with what you do in the course of the day as a midwife, what you do to your patients and what can people expect once they have a midwife with a nurse such as you?

Yes. So there are such a lot of misunderstandings about what the midwife does, but I’m in a hospital midwife. So I work in the hospital, and my day by day in principle I enter each inductions, where I manage delivery, deliver children, fix the vagina after delivery and make postpartum rounds. But my aspect of the supplier enters the hospital and makes sure that the pregnancy is strictly because the patient wants it, informing the patient that they’re the writer of their history and that they will support themselves and I’m with them on the best way.

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And what in regards to the biggest misunderstandings or confusion relating to obstetrics?

There are so many misunderstandings, but the largest misunderstanding is that the midwife and doula are the identical. So let me clean it now. Midwives and Doulas, each are crucial suppliers for delivery, but midwives are providers of medical service. So we’re suppliers who provide a toddler. So when the kid leaves, we deliver. When the vagina have to be repaired, we repair. And Dulas, also they are needed, but they are usually not suppliers in the physical aspect, but more emotional and spokeswoman. Basically, I wish to frame them as a second daddy. And they’re in favor of the patient. They are educated to assist their mother during childbirth, pregnancy, prenatal, postpartum. So each are needed, but midwives provide children like Ob-Gyn. And Dulas helps from an emotional standpoint.

What do you want on the work you do best?

I really like to be a part of the most sensitive, exciting a part of a lady’s life. You do not have many such moments as a lady. So being a part of it with women, especially black women, when it is commonly terrifying, lots means to me because I can support them once they are unable to support themselves.

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Pretty. I find it irresistible. I find it irresistible. So a nurse, she is here to offer us not only this information, but additionally break down some myths and things that it’s essential to know and take into consideration whether you might be preparing for a toddler and you desire to have a certain birth team that’s more supporting, understanding and helpful, and be certain that you might be protected and have the perfect possible delivery. So we’ll give her floor and let her divide five things it’s best to know for those who are considering a midwife.

Why midwives matter - and what most people commit in them
Courtesy of the topic

Hello everyone. My name is Myqueen Dickens. I’m a licensed midwife, and today I will provide you with five things it’s best to know in regards to the midwife’s care.

Number one: The biggest misunderstanding in regards to the midwife’s care is that the midwife and doula are the identical. Midwives are suppliers who deliver children and Dulas are from an emotional standpoint. Both are needed throughout the birth.

Number two: The second misunderstanding is that midwives can only deliver at home. In fact, we will provide in different settings. So we’re talking about home birth, a middle of delivery and a hospital. So knowing you can be protected in every setting that you’re going to select until birth. You do not have to be afraid of hospital ladies, spokeswoman is for you. You can have doula in the hospital. You can have a midwife. You can have the specified delivery team.

Number three: Most people imagine that midwives are only available while pregnant and postpartum, but midwives can deal with you throughout their life. As a midwife woman, she will be able to deal with a newborn baby up to twenty-eight days, in addition to the health of Gyn and Women. So we’re talking about prenatal, postpartum, birth, in addition to perimenopaus and menopaus.

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Number fourth: When we discuss delivery, it’s best to definitely have a plan. Now I do not really like resonance with delivery plans, but I believe you have got to have a delivery guide. Your birth, your job, might not be as planned, but I need you to call. I need you to have something in place. Having a delivery guide that can lead you thru this experience will probably be very essential that exactly the way you will move after birth, delivery, after delivery, and there are various different resources to make use of. There is a tremendous company called Motherly Touch, which actually has postpartum bags, in addition to delivery guides for girls who will help them plan the experience of childbirth.

Number five: You are the writer of your delivery history. You have control. You are capable of support yourself. You are capable of create your dream birth team, no matter whether it’s a midwife, doula, lactation consultant. You are capable of do it in any environment.


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This article was originally published on : www.essence.com
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Health and Wellness

The loss of empathy is a key problem in people with frontal and anti -protection dementia – our studies show what is happening in the brain

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The frontally and defense dementia has gained significant attention in recent years after the actor’s family Bruce Willis announced in 2023 that he was The state was diagnosed. A yr later it was revealed that she was hosting Chat in the USA Wendy Williams The state was diagnosed.

However, despite this recent attention, we still have no idea much about the frontal and protective dementia – including what mechanisms cause certain symptoms and how we will higher detect the signs of the disease. But Our research He discovered brain processes underlying one of the earliest symptoms of the disease. This discovery brings us a step cling to higher diagnosis and treatment of state.

Frontal dementia About 5% of dementia cases. Symptoms often start in the sixties or seventies. The disease primarily affects the behavior, personality and language skills.

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The diagnosis of frontally -protective dementia, which distinguishes it from other forms of dementia (equivalent to Alzheimer’s disease), is the early loss of empathy. This often manifests itself as reduced heat and concern for family members. This symptom may be deeply disturbing for members of the family and family members much like the patient. They may feel as if the patient’s personality has modified – and that his efforts to assist and support meet with indifference.

One sec Loss of empathy He was the subject Many research From the scientific community, precise brain mechanisms underlying the loss of empathy in the front -protective dementia remain unclear.

Together with colleagues from the Karolinska Institute, Lund University and Umeå University in Sweden, we conducted a study that was trying Understand how empathy decreases In front -and -protection dementia. We checked out 28 patients with frontal -protective dementia and compared them with 28 healthy people.

To conduct our study, we used a type of brain scanning called functional magnetic resonance imaging (FMRI). During the FMRI scanner, participants checked out the images of hands punctured by the needles. These paintings were contrasted with images affected by Q-tip hand. This is a well -established neuronouki test, which goals to cause a sense of care and suffering as a witness of one other person in pain. We analyzed the brain activity of patients with frontal and protective dementia while viewing images.

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In healthy volunteers, the front of the front rims and the hill are the regions of the brain chargeable for monitoring internal body signals (equivalent to pain). These cerebral systems became energetic after they observed paintings in pain.

In patients with frontal and protective dementia (poem D), their brain activity has hardly modified while watching a person in pain.
AuthorIN Author given (without reuse)

But in patients with frontal and protective dementia, activity in these key areas of the brain has been significantly reduced. These reductions were strikingly related to the degree of empathy, which patients showed in their every day lives, as they’re assessed by questionnaires filled by members of the family.

Empathy and brain function

It is often believed that empathy consists of two dimensions. Empathy is the ability to answer the feelings of others (equivalent to their suffering and care). Cognitive empathy is the ability to grasp the intentions of others.

Although each are closely related, they aren’t the same. It is also possible that a person has one aspect of empathy, but not the other. The difference between Two points of empathy You can actually illustrate two psychiatric conditions, anti -social personality disorder and autism.

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People who’ve been diagnosed with anti -social personality disorder are frequently good in understanding other people’s intentions and motivations (Cognitive empathy), but he cannot feel emotionally. This can result in disregarding other people. On the other hand, a person with autism often has the ability to emotional empathy, but may not find a way to use for other people’s intentions (Cognitive empathy).

Our study revealed reduced activity in the brain part associated with monitoring the brain of body states, which are frequently used during emotional empathic with one other person. These discoveries emphasize the critical relationship between this brain system and our ability to consider others.

In the light of these findings, the next step in our research is to look at whether and in how the flow of signals of the body needed to create an internal I is modified in frontal and temporary dementia-as it refers to empathy.

https://www.youtube.com/watch?v=W6vejeqobqe

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Apart from About 30% of cases are geneticThe causes of the frontal and protective dementia remain unclear. Despite intensive efforts from the community, there is no cure. But due to the brave suffering and their families coming forward, consciousness is growing. This is a key continuation.

We hope that understanding how the brain converts empathy into frontal -protective dementia can’t only help improve the diagnosis, but in the future can pave the path of potential treatment that soothes some of the destructive effects of this disease.

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This article was originally published on : theconversation.com
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