“Science has been a process of continuous advancement towards objective truth”

October 26, 2017 in In the News

 

This is one statement from which I wrote an essay for, in a past paper for the BMAT. The BioMedical Admissions Test, alongside the UKCAT, is one of the medicine admissions tests that medical schools might ask for and consists of 3 sections: Aptitude and Skills, Scientific Knowledge and Applications and a writing task. Unfortunately, pretty much the only way to prepare for either admissions test is practice, practice, practice so I decided to share one of my practice writing tasks with you….

 

This statement suggests that developments in science have all, always been working towards the discovery of a set of unchanging and unbiased facts. It suggests that the goal of all science is eventually to uncover these facts that have been consistent throughout mankind’s scientific journey. For example, the ‘discovery’ of gravity by Newton. Gravity has been around and affecting us always but only became apparent relatively recently, and cannot be denied or manipulated.

However, it can be argued that advancements in science have not been continuous, as we have had periods of rapid advancement followed by periods of stagnation often due to the limits of technology preventing further advancement. For example, the improvements in the microscope allowed for the Germ Theory to be discovered consequently. Sometimes, incidentally, stagnation was not brought on by technological limits but by limits to scientific advancement out of fear such as the Church historically discouraging new theories and discoveries of Galileo’s out of fear that they would challenge their teachings.

What’s more, it can be argued that the truths we work towards discovering are in fact not objective, nor as they unchanging as the statement might suggest. This ‘objectivity’ supposes that scientific fact is not affected by societal influences however I would argue the contrary, as the way those truths are perceived very much depends on when in history they are discovered and the state in which society is in at the time. Moreover, the scientific truths have not and will not always be the same as science is not as constant as it may seem. Facts are constantly changing, for examples evolution drives changes and adaptations in organisms, the universe is constantly changing with its expansion and the emergence or disappearance of stars.

The truths that science offers are always changing slowly but surely so that we are not working towards the same truths they may have worked towards a millennia ago an for this reason I cannot agree with this statement. Whilst science is about advancement, it is not always continuous and the truth is not objective.

Should school start times be changed to accommodate the change in circadian rhythm which occurs during adolescence?

October 9, 2017 in Difficult Debates

 

Okay, I know it’s a longer-than-normal title but that’s because it was also the title to the EPQ I carried out last year. For those of you that are unfamiliar with the EPQ, it stands for ‘Extended Qualification Project’ and is essentially a research project about anything you choose. At the end, you either make a product or write an essay; guess which I did? I wrote an essay debating whether or not high school start times should be changed or not, and found the topic so interesting that I thought I’d share a condensed version with you readers!

First things first: are teenagers actually sleep deprived? Constant tiredness is a stereotypical feature attributed to teenagers but are they really losing out on sleep or is it just every day complaining? The recommended amount of sleep for a teenager is about 9.25 hours, but the average that teenagers actually get is around 7 hours per night. This means that they are indeed sleep deprived, so much so that British children are rated to be the 6th most sleep deprived worldwide!

Sleep deprivation is very much a public health issue in my eyes, as the effects of it are detrimental to both physical and mental health. Coordination and endurance are hindered by tiredness, as well as skin problems and even metabolic deficits like obesity being linked to it. Mood can be poorly affected too, with higher occurrences of feeling unhappy or depressed. Outward behaviour can also change from being sleep deprived, with aggressiveness and irritability being seen in subjects lacking in sleep. This can harm relationships between teens and their friends and family. This, coupled with the increased feelings of sadness can lead to incidences of depression. Inordinate sleepiness also makes it difficult to concentrate and stay alert, as I’m sure any teenager you asked could testify to, making it hard to maximise learning at school.

But why are young people so tired? Well, some of this sleepiness could be explained by the teenage circadian rhythm. The circadian rhythm regulates when you fall asleep and wake up, but this sleep timing is all pushed back by 1-3 hours during puberty. More specifically the secretion of the ‘sleepy’ hormone, melatonin, happens and stops happening later into the night and morning. This means that teenagers naturally fall asleep later at night and wake up later in the day than an adult would.

As a result, waking up early enough to get to school by 8:30am clashes with the natural teenage sleep cycle. This impacts not only sleep length, but also quality. Clearly, if an adolescent struggles to fall asleep before 11pm but must wake at 6:30am then they’re not going to get the recommended 9+ hours of sleep needed. But the social jet lag effect created by ignoring your natural body clock results in poorer quality of sleep. Not to mention, the famed weekend lie-in is actually caused by a build-up of ‘sleep debt’ over the week. The body makes an effort to catch up on missed sleep after a week of deficit, but this later waking time on weekends leads to irregular sleep patterns. As I mentioned in my previous post about sleep, lack of routine damages sleep quality so lie-ins aren’t actually good for you.

So… could changing school start times help? Well, researchers at Oxford University predict that by changing high school start times from 8:30am to 10am, GCSE attainment could improve by 10%! This is because of the improved cognitive ability, concentration and attitude that would be seen as teenagers got more, better quality sleep. Thus by starting later, schools would be helping themselves and their students to maximise the time spent at school. Not only that, but the time spent out of school would also be put to better use as increased productivity would mean homework would be completed faster leaving more time for extra-curricular activities.

As I said before, sleep deprivation has very poor effects on young people. Naturally, by allowing teens to get the sleep they need many of these effects would be reversed leading to happier and healthier young people. The actual scale of these improvements can’t be predicted, but given the huge issues that the NHS currently faces with obesity and depression in youths, any improvements would be worth it- or would it?

Changing school start times, as simple as it sounds, would actually be a massive change. Transportation would need to be reorganised, new contracts for teachers would need drawing up, parents would need to change shifts or hire childcare and there would be less time available at the end of the school day. As well as school buses being used, many high school students and staff also use public transport. The shift in timings could affect costs to schools hiring buses and increase congestion, as the later finish would add to rush hour traffic and therefore travel times. This argument is full of faults though. I struggle to understand how the exact same route and the exact same number of buses and drivers would somehow result in higher costings just because it happens 2 hours later in the day. Also, whilst I can see how congestion could be made worse, at least less congestion would be found in the mornings as the rush to school and work would occur in staggered waves.

The later finish time is a common concern amongst young people, as it would leave less time after school for extra-curricular activities, homework and free time. For sports teams relying on outdoor practice, the loss of daylight hours could lead to less practice time and more competition between clubs for use of facilities. Similar competition over facilities could be found in other extra-curricular clubs, as well as less time being available for use of public services like the library. Less time to do homework after school is also a worry, though I have already mentioned the increased productivity that has been found in well-rested subjects meaning less time would actually be required to carry out the same amount of work.

Opposition from teachers would inevitably arise if school start times changed, for one thing because the later finish time added to the work many teachers do after school would result in very late finishes and isolation from their families as schedules clash. However, because adults do not need to wake up as late as adolescents do, teachers could easily adapt to the new school timings by moving all their extra work to the morning hours before school began and would still have the evenings to enjoy with their families.

Additionally, with high schools no longer starting and finishing around the same time as primary schools, childcare issues could cause a lot of stress for families. With older siblings no longer available to supervise younger siblings, parents would either need to change their shifts to make sure they’re home or pay for childcare. This would hit lower-income families the hardest, as lower-paid jobs often correspond with a lack of flexible working hours and to pay for childcare would leave behind less disposable income.

Finally, the sleep deprivation found in teenagers cannot be linked solely to their circadian rhythm. As with most things, a multitude of factors can be blamed either partially or wholly for the trend found and in this case the other considerations to think about are behaviour and the homeostatic system. The homeostatic system is yet another biological process that affects our sleep, but this time it affects sleep/wake length. Regardless of the time of day, the homeostatic system causes ‘sleep pressure’ to build up which can only be relieved by sleep. Now in teenagers, this sleep pressure takes longer to build up over the course of the day than it does in younger children which means that the desire to go to sleep kicks in later in teenagers which could explain the late bedtimes.

Another bit of biology for you: the circadian rhythm is controlled by the hypothalamus which detects light and dark signals in the environment and responds by releasing hormones, adjusting body temperature, etcetera to make you fall asleep. The key role that light plays in controlling our sleep timing and our ever-increasing use of technology may be a big contributor to why teenagers struggle to fall asleep at night. The blue-wavelength light emitted by electronic devices mimics daylight, tricking and stimulating the brain into staying awake and not triggering all of those bodily functions which make us feel tired. No doubt if you asked any young person, they could confirm to you that they routinely utilise some kind of electronic device in the 30 minutes before going to bed. And it is this behaviour which could be making it difficult for teenagers to fall asleep at night thus adding to sleep deprivation.

So you see, there is no simple answer to the seemingly simple question. There may be some biological component which fights against adolescents waking up early, but would fixing that fix the whole problem? And is it worth the effort it would require to implement such a huge change? In my opinion, even the smallest improvements are worth it. I know from experience what a huge difference just one extra hour of sleep makes to my mood and to how I receive the rest of my day. Imagine millions of people just that little bit happier, and what might’ve seemed like a small difference at first becomes something a lot bigger and better. As for the other question, realistically I don’t think that to only change school start times would completely fix the issue of sleep deprivation, but it is a start. For the best results, I would say that education on the importance of sleep and good sleep hygiene should be taught in schools alongside the start time changes.

Genetically Engineering the Human Embryo- is it ethical?

September 29, 2017 in Difficult Debates

 

Genetically engineered crops have been in use since the late 90s, and even that has flared up opposition based on possible risk to human health, the environment and other unforeseen repercussions. So mention genetic modification of humans, and the immediately conjured image is that of a perfect, superior and absolutely terrifying race of people that seem far less human than us. Whilst the technology for such things aren’t quite in our grasp yet, I think it is worth keeping tabs on just how advanced genetic engineering is becoming and start considering the consequences… before it’s too late (dun dun duuuuuun!).

So where are we at right now? Well, in 2015 this debate was reignited by a group of Chinese researchers who attempted to remove a mutated gene causing a deadly blood disorder from non-viable embryos. They did this using the game-changing gene-editing CRISPR-Cas9 tool which came about in 2013. CRISPR is part of a natural defence mechanism within bacteria against viruses, and cas9 is an associated enzyme to CRISPR. When it comes to genetic modification CRISPR-Cas9 can be manipulated to cut out any section of DNA, and if a new piece of DNA is placed near the cut site it is accepted by the body as a replacement. This means that ‘bad’ genes can be removed and replaced by the healthy version, but it’s not as straightforward as it seems. The research in China had to be abandoned partway through, because unintended mutations were found in the genome which could cause cell death and transformation. Clearly, not a great outcome but it did, as I said, grab the public’s attention and get people talking about it which in itself is a much needed effect.

Since then, research on human embryos has been carried out in various places but never with the intent to implant them into a woman. Recently, details of the first successful genetic modification of a human embryo in the US were released. The scientists also used CRISPR, this time to remove the mutation causing a heritable heart condition which can cause sudden cardiac death. This was an exciting discovery but again would not result in implantation. So why not? Implantation of genetically modified embryos is illegal everywhere, with any research at all in the UK being very limited. But should it be?

Let’s first consider how genetic engineering of embryos could be an asset to the medical world. The most obvious use for genetic modification is to use it to eradicate genetic diseases. Countless diseases, many of which are very dangerous, are caused not by viruses or bacteria but due to mutations in our DNA. Whilst genetic engineering cannot help those already living with such a disease, it can prevent those diseases from being passed on to offspring and future generations. Long term, this could lead to targeted diseases eventually dying out. Clearly, that would be a desirable outcome which could save many lives. But as well as how dangerous a disease may be, it is important to also consider how living with that disease affects quality of life.  Many genetic diseases, like cystic fibrosis, can only be managed rather than cured. That management can sometimes require a lot of care to be provided by medical staff and/or family members and can limit the freedom and capability of sufferers. By correcting the mutation in an embryo which screens positive for a certain disease, the resultant baby when born would be void of the disease as opposed to having to manage the condition for the rest of their lives.

Some have suggested that the need to eradicate genetic diseases is unnecessary, given that embryo screening means parents who are concerned about passing on a disease to their offspring can screen embryos and select to use those which are healthy. However, this method still results in diseased embryos being destroyed which in itself is considered unethical dependant on at what point you believe life begins. Furthermore, some parents can go through countless expensive IVF treatments, screening each time, and still be unable to produce an embryo which doesn’t have the disease. In this case, the only other way to ensure a child can be born from those parents is from the use of genetic engineering.

One fear voiced by some is that any change to our DNA could create a butterfly effect, with unpredictable consequences affecting future generations with altered genes. Indeed any change would always carry a risk of unexpected and unwanted repercussions and so any and all genetic modifications would need to be considered carefully to try to minimise the occurrence of such ramifications. Some say that better yet, no changes should be made full stop to the human genome as the risk isn’t worth the benefit. This argument could be coupled with the above one, ensuing that genetic engineering is not necessary as alternative options are available so why take the risk for something that isn’t an absolute must?

A similar issue surrounding genetic modification is the idea that by selecting or ‘deselecting’ certain genes and versions of genes, we make the gene pool smaller and reduce genetic diversity. In the future, this could cause problems should the deselected genes became useful, desired or even necessary. For example, if a disease was deadly to everyone except those with a certain mutation but that mutation was no longer around due to genetic engineers targeting the removal of it, then the human race could be seriously under threat. Of course, this is a worst-case-scenario example but one which still needs to be considered, not to mention that lower scale versions of this could happen also. There is a flaw with this argument though, in that I struggle to see how the mutation for, say, Down’s syndrome could benefit future generations. Whilst I understand that we should preserve as much genetic variety as possible, I do not think that retaining genes which are not just ‘undesirable’ but are actually harmful and causes suffering is necessary for the sake of genetic diversity.

Finally, and most importantly to most people, there’s the matter of designer babies. Even with the emergence of genetically modified crops, worries about the applications in humans to create designer babies were loudly voiced. The selection of certain characteristics which are considered more desirable, such as intelligence, would clearly be wrong… wouldn’t it? Of course, one could say that a great many characteristics, physical or otherwise, do have some sort of health benefit so it is ethical to seek them. After all, medicine looks not just to cure illness but prevent it and improve quality of life. So it stands to reason that if freckles are associated with a higher risk of developing skin cancer, then genetic modification to remove freckles makes sense, no? And if self-esteem issues could be prevented by genetically engineering babies to make attractive adults, would that not improve the mental health of the general population?

I’m hoping at this point that you can see the point I am leading into, and not just cheering me on. Almost all genetic modifications can be argued to be of value medically, with some arguments being admittedly less believable than others, and so we reach the heart of the problem with genetic engineering; at what point is the modification acceptable, and when have we gone too far? And so the solution for many is to just proclaim all modifications are unacceptable, and the result is that no progress can be made because everyone is too busy worrying about the worst case scenario.

But how likely is this scenario, really? Already, research happening now must have ethics approval. The currently proposed use of genetic engineering would be carefully monitored and controlled. Any governments that endorsed it would no doubt be setting guidelines and restrictions to make sure it didn’t get out of control, wasn’t misused and was safe and ethical. If these rules set out were even in the least bit breached, the watchful eye of the authorities would be alerted and the scientists could be stopped long before they got anywhere close to the production of ‘designer babies’.

What’s more, many characteristics are not solely controlled by genes, but by environmental influences. And even though genes do play a part in it, often more than one gene affects a feature that a person may have. So qualities like intelligence or sportiness can’t just be ‘manufactured’ into a person, and the emergence of designer babies isn’t quite as realistic as people fear it could become.

Whether you agree with genetic engineering embryos or not, the most important thing right now is that the matter is brought to the public eye in a big way. We need people talking and thinking about where they stand on the matter, so we can begin to put regulations like the ones mentioned above into place. Perhaps society will continue to ban genetic engineering altogether, as it generally has in the past. Or maybe, common sense and a little faith in the human race not to take it too far will push us into the future, one with fewer genetic diseases and less suffering.

Vampire or Victim?

August 3, 2017 in History, The Science Behind...

 

Brasov in Transylvania, Romania

Following my recent trip to Transylvania in Romania for work experience, I have decided to dedicate this post to the monsters and myths which stem from the region: specifically vampires. Like many historical ideas and beliefs, the creation of such a supernatural being likely served as an attempt to explain ailments that couldn’t otherwise be explained, before the emergence of scientific understanding. In this post, I will describe the medical condition most popularly believed to have led to belief in vampires.

The most commonly referenced illness used to explain away vampirism is porphyria, a group of inherited metabolic disorders in which haem (used in haemoglobin) production is disrupted. The production of haem from a chemical called ALA involves several steps, and each step requires the use of an enzyme. In people suffering from porphyria, one of those enzymes is faulty due to the inheritance of a mutated gene which codes for the synthesis of that enzyme. This means that the production of haem is slowed or even stopped, and as a result the ‘transitional chemicals’ made in the stages between ALA and haem, known as porphyrins, can build up to harmful levels. As well as this, the limited haem production can mean that not enough healthy red blood cells can be made. There are different types of porphyria depending on which enzyme is dysfunctional, most of which produce different symptoms with some overlap.

The most common form, and the one best related to vampires, is porphyria cutanea tarda (PCT) which affects the skin. PCT causes photosensitivity in which exposure to sunlight can cause painful, blistering and itchy skin… sound like something you’ve heard of before? A well known characteristic of vampires is that they burn in sunlight, hence must stay out of the sun and so have a dramatically pale complexion. Similarly many porphyria sufferers are indeed pale as, naturally, they avoid the sunlight due to their photosensitivity.  What’s more, healing after this reaction to sunlight is often slow and, with repeated damage, can cause the skin to tighten and shrink back. If this shrinking causes gums to recede, you can imagine that the canines may start to resemble fangs.

Another general symptom of porphyria is that when the accumulated porphyrins are excreted, the resultant faeces may turn a purple-red colour. Whilst the same conclusion may not be reached in modern times, historically this may have given the impression that the sufferer had been drinking blood which is another vampire hallmark. Interestingly, drinking blood could- and I say this tentatively- actually relieve some symptoms of porphyria. Whilst the haemoglobin would be broken down, the haem pigment itself could survive digestion and be absorbed from the small intestine meaning in theory that drinking blood would do the same for relieving symptoms as a blood transfusion would. Finally, garlic. Seemingly the most random trait of vampires is their aversion to garlic however even this could be explained by porphyria. Garlic can stimulate red blood cell and haem production which, for a person with porphyria, could worsen their symptoms as more porphyrins build up. This could lead to an acute attack in which abdominal pain, vomiting and seizures may occur. Seems like an extreme reaction, but perhaps…

So does porphyria explain how the legends of vampires came about? I would say so, but some folklorists and experts would disagree. It is suggested by such people that porphyria doesn’t accurately explain the original characteristics of vampires but more the fictional adaptations that have more recently been referred to. Folkloric vampires weren’t believed to have issues with sunlight at all and were described as looking healthy, ‘as they were in life’, which contradicts the pale complexion and blistering skin seen in PCT. Furthermore, it is still unclear whether or not drinking blood would truly relieve symptoms of porphyria and even so, how those affected would know to try it with no understanding of their disease and no craving for blood makes it all seem rather unlikely. Speaking of probability, reports of vampires were rampant in the 18th century yet porphyria is a relatively rare  occurrence and its severity ranges from full-on vampire to no symptoms developing at all, making it seem even less probable that such an apparently widespread phenomenon could be the result of PCT.

Whether you believe that porphyria caused the vampire myths or not, it certainly is an interesting disease that sadly has no cure (so far), is difficult to diagnose and relies generally on management rather than treatment. Here’s hoping that future developments using gene therapy and even research spun off of use of ‘vampire plant’ models could lead to improvements some day.

‘Carbon dating’ cancer? What’s that all about?

May 16, 2017 in In the News

 

Last week, the Institute of Cancer Research announced that scientists have been able to precisely pinpoint the timing in which different stages of a patient’s cancer developed. This could result in some interesting progress in the treatment and understanding of cancer and I will explain how researchers are doing this, but first- what is cancer?

Cancer is a group of diseases caused by the uncontrollable division of damaged cells. Cells can become damaged in this way due to a mutation in their DNA which intervenes with the regulation of mitosis (cell division). More specifically, the genes proto-oncogenes and tumour suppressor genes can become mutated. Proto-oncogenes trigger division, however mutated ones (known as oncogenes) trigger mitosis to happen at a much faster rate than normal. Meanwhile, mutated tumour suppressor genes fail to inhibit cell division as they should. Both mutations, as you can imagine, lead to the fast and furious growth of a cell into a tumour.

Mutations naturally occur quite frequently, but not all mutations cause cancer, and in fact it often requires more than one mutation in a cell in order for it to become cancerous. Most of the time either the mutation is relatively harmless, the DNA is repaired or the cell ‘kills itself’ before it can do any harm (apoptosis). However, in cancer cells the signals telling them to undergo apoptosis can be overridden so that the damaged cell continues to divide, producing even more damaged cells.

There are multiple methods currently in use to treat cancer, but the three most common treatments are surgery, chemotherapy and radiotherapy. In surgery, the tumour is simply removed from the body however this only completely cures if the cancer is contained in one area and hasn’t spread. Surgery is often used in combination with other treatments such as chemotherapy to shrink the tumour before surgery (neo adjuvant treatment).

Chemotherapy is the use of drugs to treat cancer, usually by stopping cells from dividing. The drugs do this by either preventing DNA from replicating (which occurs in the time preceding mitosis) or by interrupting mitosis during the metaphase stage. Chemotherapy is most effective against rapidly dividing cells like cancer cells but it can also effect other cells which divide frequently such as hair-producing cells. This explains some of the side effects such as loss of hair that can occur during chemotherapy.

Radiation works by damaging the DNA in cells that are dividing using high-energy rays (normally x-rays). Seems confusing, doesn’t it, given that cancer itself occurs due to damage to DNA in the first place? Radiation is different because the way in which it damages the cells means that they can’t grow or divide anymore. That damage can generally be repaired in normal cells, but not always which is why there are unwanted side effects to radiotherapy, but cancer cells cannot fix themselves so they die over time.

So now that you are clued up on how cancer occurs and can be stopped, back to carbon-dating. Carbon dating is used to determine the age of organic matter by measuring the amount of carbon-14 that they contain, but here’s the burn- I’m not really talking about carbon dating. Sorry! Don’t leave just yet, because what these scientists did to find out when various stages of cancer progressed in a patient is still pretty interesting. The researchers used genetic analysis and mathematical models that’s normally used in evolutionary biology and applied it to cancer instead. In evolutionary biology, genetic data from current species can be used in combination with carbon-dated fossils of ancestral species to estimate when the current species- or species in between ‘now’ and ‘then’- arose throughout history. Now you can perhaps see why the carbon-dating link comes in.

These methods could only be applied, however, due to a needle tract tumour which occurred when a biopsy of the patient’s tumour was taken. What this means is that a sample of the cancer was taken using a needle and where that needle was removed, some of the cancer cells contaminated the needle track. These cancer cells grew into a metastatic tumour (tumour which has spread from the primary site of cancer to a different area) but because the scientists knew exactly when this tumour happened, the genetic data from these cancer cells could be analysed and compared etcetera etcetera so that a timeline of how the cancer had started and spread was made.

This timeline is useful because it could help with diagnosis and treatment, not only directly but also from what else the scientists found. The researchers discovered that the cancer spread faster during the first year, however after metastasis this progression slowed. What this suggests is that the degree of genetic instability may play a more important part in the deadliness of cancer  than the amount that the cancer has spread. This could be used to determine a patient’s prognosis more accurately, and could help doctors when evaluating how well a treatment might- or might not- work. Furthermore, tracking a cancer’s progression could enable doctors to better predict the cancer’s behaviour in the future thus influencing the strategy for treating it.

So that’s a bit of information about what cancer is, how it can be treated and a recent research development in the field. Some of what I have shared in this post, I learnt at a ‘medicine insight day’ hosted by a group of medical students at Oxford University. They shared with us tips on how to get into university, explained some of the science in cancer and educated us about ovarian and testicular cryopreservation- a method to preserve the fertility of teenagers who have survived cancer.

This preservation is necessary because if a young person survives cancer, the treatment against cancer is often so aggressive that an ‘early menopause’ is triggered in the patient meaning they become infertile (unable to have children). The Future Fertility Trust is  charitable trust fund which offers cryopreservation in which ovarian or testicular tissue is collected, stored and re-implanted after cancer treatment. This enables young cancer survivors to have children in later life, however the work is not funded by the NHS so relies on donations and fundraising. I would like to see ovarian and testicular cryopreservation help more young people and hope that it might become available to all young people by the NHS is the future, and this could be possible if enough cases are funded to show the usefulness and success of  the technique. If you would like to find out more about cryopreservation, Future Fertility Trust, or to donate, go to http://www.futurefertilitytrustuk.org.

Peanut or Pea-not?

April 29, 2017 in The Science Behind...

 

The humble peanut is much loved around the world, making up 67% of all nut consumption in the US and can be found as an ingredient in a ridiculous number of foods or eaten as a savoury snack. Unfortunately, peanut allergy is also one of the most common food allergies with about 1 in 100 people in the UK being allergic.

My interest in this topic arose when someone broke the news to me that the peanut is not actually a nut. Okay, so maybe not the most ground-shaking piece of information but a surprise to me all the same. Turns out, the peanut is actually a legume. This is because a nut is considered to be a fruit whose ovary wall become very hard at maturity, hence the phrase “tough nut to crack”. Also, nuts tend to grow on trees. In contrast, peanut pods split open when ripe and they grow underground. In fact, they are scientifically classified as Arachis hypogaea with hypogaea meaning ‘under the earth’.

Peanuts actually play a lot of roles in health and medicine. In terms of nourishment, peanuts are a great source of protein. They are richer in protein than soy beans and just two tablespoons of peanut butter has more protein than an egg. They also contain nearly 50% fat- but don’t worry! 70% of that fat is unsaturated so whilst that still makes them rather calorific, they are a very good source of energy. Mineral content such as potassium, phosphorus, iron, zinc, copper and magnesium is also proportionately high in peanuts. Finally, peanuts have a lot of vitamin B.

In relation to medicine, peanuts are rich in resveratrol which has antioxidant properties. This helps control cholesterol and prevent heart disease. Peanuts also have an abundance, it seems, of genistein which is known to combat PMS and also prevent the development of cancer cells. One of the many amino acids in peanuts is tyrosine. Tyrosine is used by our bodies to make dopamine, also known as one of the ‘happy hormones’. Lack of dopamine is actually associated with ADHD (attention deficit hyperactivity disorder) in children which can cause problems at school. However, as with everything in life I would not recommend a huge intake of peanuts just for these health benefits as anything in excess can be harmful.

Speaking of harmful, what is a peanut allergy and why does it happen? A peanut allergy occurs when the body’s immune system mistakenly believes that peanuts or something in the peanuts are harmful, so produces an immune response to attack those allergens. During an allergic reaction, histamine is released by mast cells which are found in connective tissues, like the skin. One of the effects of histamine is that it causes capillaries to become more permeable to white blood cells. As a result, fluid moves out of capillaries creating symptoms like watery eyes and runny noses.

Antihistamine can be used to relieve the symptoms of a mild allergic reaction but in a severe reaction anaphylactic shock can occur in which case emergency medical treatment or an injection of epinephrine (adrenaline) as advised by a doctor is required. The best treatment is to steer clear of peanuts if you’re allergic. Although peanuts are not a nut, as we recently found out, if you have a nut allergy you are likely allergic to peanuts too (and visa versa). This is because the allergens are similar so the body responds in the same way.

So that’s a bit about peanuts and nut allergies, but also about some of the benefits of the superfood too. With over 40 million tonnes of shelled peanuts produced worldwide, peanuts are indeed a very popular foodstuff, whether they are a nut or not…

Peanut or Pea-not?

April 29, 2017 in The Science Behind...

 

The humble peanut is much loved around the world, making up 67% of all nut consumption in the US and can be found as an ingredient in a ridiculous number of foods or eaten as a savoury snack. Unfortunately, peanut allergy is also one of the most common food allergies with about 1 in 100 people in the UK being allergic.

My interest in this topic arose when someone broke the news to me that the peanut is not actually a nut. Okay, so maybe not the most ground-shaking piece of information but a surprise to me all the same. Turns out, the peanut is actually a legume. This is because a nut is considered to be a fruit whose ovary wall become very hard at maturity, hence the phrase “tough nut to crack”. Also, nuts tend to grow on trees. In contrast, peanut pods split open when ripe and they grow underground. In fact, they are scientifically classified as Arachis hypogaea with hypogaea meaning ‘under the earth’.

Peanuts actually play a lot of roles in health and medicine. In terms of nourishment, peanuts are a great source of protein. They are richer in protein than soy beans and just two tablespoons of peanut butter has more protein than an egg. They also contain nearly 50% fat- but don’t worry! 70% of that fat is unsaturated so whilst that still makes them rather calorific, they are a very good source of energy. Mineral content such as potassium, phosphorus, iron, zinc, copper and magnesium is also proportionately high in peanuts. Finally, peanuts have a lot of vitamin B.

In relation to medicine, peanuts are rich in resveratrol which has antioxidant properties. This helps control cholesterol and prevent heart disease. Peanuts also have an abundance, it seems, of genistein which is known to combat PMS and also prevent the development of cancer cells. One of the many amino acids in peanuts is tyrosine. Tyrosine is used by our bodies to make dopamine, also known as one of the ‘happy hormones’. Lack of dopamine is actually associated with ADHD (attention deficit hyperactivity disorder) in children which can cause problems at school. However, as with everything in life I would not recommend a huge intake of peanuts just for these health benefits as anything in excess can be harmful.

Speaking of harmful, what is a peanut allergy and why does it happen? A peanut allergy occurs when the body’s immune system mistakenly believes that peanuts or something in the peanuts are harmful, so produces an immune response to attack those allergens. During an allergic reaction, histamine is released by mast cells which are found in connective tissues, like the skin. One of the effects of histamine is that it causes capillaries to become more permeable to white blood cells. As a result, fluid moves out of capillaries creating symptoms like watery eyes and runny noses.

Antihistamine can be used to relieve the symptoms of a mild allergic reaction but in a severe reaction anaphylactic shock can occur in which case emergency medical treatment or an injection of epinephrine (adrenaline) as advised by a doctor is required. The best treatment is to steer clear of peanuts if you’re allergic. Although peanuts are not a nut, as we recently found out, if you have a nut allergy you are likely allergic to peanuts too (and visa versa). This is because the allergens are similar so the body responds in the same way.

So that’s a bit about peanuts and nut allergies, but also about some of the benefits of the superfood too. With over 40 million tonnes of shelled peanuts produced worldwide, peanuts are indeed a very popular foodstuff, whether they are a nut or not…

The Secret to Getting Good Sleep

April 21, 2017 in Everyday Medicine

 

Now I’m not particularly athletically inclined, try as I might, but the one thing that I could win at is getting good sleep. Of course practice makes perfect, but a few tips on how to fall asleep faster and sleep better can really make all the difference…

 

First of all, what should you be aiming for? It varies, but in general teenagers need around 9 hours and adults need about 8 hours. That’s the first step to winning; make sure you actually give your body enough time to grow, repair and everything else mentioned in my previous post, ‘The Science Behind Sleep’.

The next key aspects are the two R’s: regularity and routine. If you regularly go to bed and wake up at the same time everyday, your internal body clock will become ‘synchronised’ with your timings which will promote better sleep. And when I say everyday, I mean it! Weekend lie-ins can skew this schedule so try to wake up as close to your regular time as you can. This may seem like a real sacrifice but if you are able to improve your sleep quality and get enough sleep on weekdays, then weekend lie-ins will become redundant anyway.

Establishing a nightly routine before bed will indicate to your body that it’s time to wind down. Your routine could consist of a warm bath, relaxation exercises like yoga and reading a book or listening to music. Watching TV or using electronics, however, could hinder your sleep as the blue-wavelength light of bright screens can trick your body into thinking it’s daytime. This in turn causes hormones involved with falling asleep to be delayed. Therefore it is recommended you avoid such screens in the last 30 minutes before bed.

Make sure your sleeping environment is optimal with a comfortable mattress and pillow. The room should be dark, quiet, cool (between 18-24°C) and relaxing. Your diet should also work to your advantage when it comes to falling asleep. Avoid stimulants like caffeine and nicotine in the hours before sleep, and limit alcohol intake as too much alcohol before bed can disrupt sleep later at night.

Stress not only spoils the daytime, but can also cause insomnia by keeping you distracted and awake at night. It is important that you find ways to manage stress. The most obvious way of doing this would be to remove yourself from whatever is causing the stress but I’m well aware that it is not always that simple. Take basic steps to ensure at least some stress is relieved by being organised, allowing yourself to take breaks, eating well and doing exercise. Also, make time for hobbies and being with friends and do not be afraid to talk about your problems. Another good tip is to write a to-do list of what needs to be done the next day before you go to bed.

As little as 10 minutes of aerobic exercise daily can promote sleep as well as the numerous other health benefits to exercising, although in general you should avoid strenuous exercise close to bedtime. Finally, try to cap daytime sleeping to a maximum of 30 minutes. Even if you haven’t gotten enough sleep in the night, a daytime nap cannot make up for that. That said, a power nap between 20-30 minutes in the afternoon can improve alertness and mood.

The Science Behind Sleep

April 16, 2017 in Everyday Medicine, The Science Behind...

 

UntitledWe spend about a third of our lives sleeping, and many aspects of it remains a mystery to scientists but what they do know is that it is very important in brain development, muscle repair, memory consolidation and growth.

Historically, sleep was thought to be a way of conserving energy however the energy actually saved is minimal and sleeping for 8 hours only actually saves about 50kcal- the same amount of energy as a slice of toast! Another theory is that the sleep period keeps animals safe at a time of day most dangerous in terms of predator encounters. However, the lack of consciousness and response to stimuli leaves sleeping animals vulnerable so this theory is also not very strong.

The more widely accepted theory is that physical restoration occurs during sleep. During REM sleep, the majority of what happens is brain repair, restoration and development whilst non-REM sleep is mainly devoted for body repair and restoration. Many studies also show how sleep improves long-term memory processing and converting short-term memories into long term.

 

Sleep is generally split into REM and Non-REM (NREM), in which the NREM is sub-split into 3/4 other stages. NREM makes up about 75% of sleep whilst REM has the rest- in adult. Infants spend closer to 50% of sleep time in REM.

Stage 1 of NREM is Light Sleep, a state between asleep and awake. In light sleep muscle activity slows down, breathing and heart rate begins to slow down and people can be easily awoken. In stage 2, sometimes known as True Sleep, breathing and heart rate are regular, body temperature drops (by about 1o) and awareness of surroundings begins to fade. A sleeper spends more time in stage 2 than in any other.

Stages 3 and 4 are often lumped together as Deep Sleep. Breathing and heart rate reaches their lowest levels and responsiveness to the environment reduces even further. There is no eye movement or muscle activity and most of the information processing and memory consolidation takes place in deep sleep- although it does to some extent happen in stage 2 and REM. Stage 3/4 is where tissue growth and repair happens and hormones like growth hormone is released. Children may experience night terrors, bed-wetting or sleep walking during deep sleep.

Following Deep Sleep we move into REM which stands for Rapid Eye Movement. These side-to-side eye movements are intermittent and considered to be due to images seen internally during dreaming. The majority of dreams happen during REM although scientists do not know why we dream. Unlike in NREM, heart rate and blood pressure increases and breathing becomes faster and irregular. What’s more, most muscles become temporarily paralyzed during REM as brain impulses which control movement are suppressed. This is called atonia, and is thought to prevent us from acting out our dreams and possibly hurting ourselves. This theory was developed by Michel Jouvet who stopped this atonia from occurring in an experiment on cats, and consequently observed that the cats would physically run, jump and stalk prey during their dreams.

The first occurrence of REM lasts for around 90 minutes before the whole cycle begins again. Recurrence of REM becomes longer whilst periods of deep sleep become shorter over the course of the night.

 

So that’s what happens each night when you fall asleep, it’s not as simple as just ‘being unconscious’ as your body takes that opportunity to store memories, heal and dream. Watch this space for a follow up post on how to get that much needed sleep!

 

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The Science Behind the Sun

March 31, 2017 in The Science Behind...

 

As we approach Easter time, many of us will be noticing the blooming flowers and longer, sunnier days- for many of us, a reason to rejoice! The better weather definitely seems to cheer people up and boost ice cream sales, and whilst most people know to some degree that catching a bit of sun can both benefit and harm health, sun protection advice is increasingly ignored by teens wanting to tan and children wanting to play out in the sun. So I’m here to educate and tentatively advise a little bit about the sun.

 

As most people can confidently tell me, sunlight is a great- the best, in fact- source of vitamin D. But what is vitamin D? For one thing, it’s not technically a vitamin. Vitamins are generally defined as organic chemicals that are obtained from a person’s diet because they’re not produced by the body. Yet vitamin D is produced by the body and about 90-95% of it is obtained through sunlight. Also, it isn’t found in any natural foods except egg yolks and fish. Still, old habits die hard so it’s referred to as a vitamin even so.

Vitamin D is obtained from sunlight by using the sun’s ultraviolet B energy to turn a chemical in your skin into vitamin D3. D3 is then carried to your liver and kidneys, each time picking up oxygen and hydrogen molecules, to finally become 1,25(OH)2D aka calcitriol or vitamin D.

Now what vitamin D actually does is a bit more interesting. It’s best-known role is to keep bones healthy. The way it does this is by increasing the amount of calcium that can be absorbed in the intestines. Without enough vitamin D, the body only absorbs 10-15% of the calcium in our diets whilst 30-40% can be absorbed with the right amount of it. It also helps the body to absorb phosphate in our diet, which is also required for bone health.

Without sufficient vitamin D, bones can become soft and weak leading to bone deformities like rickets in children. Rickets is no longer as common as it used to be, but it causes bone pain, poor growth and deformities of the skeleton.

 

Sunlight has many other benefits, such as mood improvement. Exposure to sunlight can increase the brain’s release of the hormone serotonin, which is associated with mood boosting and a deficit of serotonin can lead to depression. There is also a correlation between the number of deaths from heart disease in the summer as opposed to the winter suggesting that the sun can reduce heart disease. UV radiation from sun exposure can be used to treat eczema (dry itchy skin), jaundice (yellowing of skin and whites of eyes) and acne and is sometimes recommended by doctors if they think light treatment would help. Finally, a moderate amount of sunlight may prevent cancer. According to a study from Environmental Health Perspectives, people who live in areas with less sun/daylight hours are more likely to have a variety of cancers including ovarian, pancreatic and colon cancer. However, too much sun can also cause cancer so it’s important to get the right balance.

 

As too many people have experienced first hand, staying out in the sun too much without protection can cause sunburn which not only is painful but also increases your chance of getting skin cancer. Sunburn is caused by the UV light from the sun which can damage the DNA in cells. As a result, the cell with damaged DNA ‘commits suicide’ (apoptosis). Cancer can occur if cells with damaged DNA do not die as they should, but instead continue to multiply. According to the Skin Cancer Foundation, people who have had 5+ sunburns have twice the risk of developing skin cancer. Another thing to be aware of is you can still get sunburnt in the UK and/or if it’s cloudy.

 

Heat exhaustion and stroke are two other serious conditions that can happen when you get too hot, sometimes from being in the direct sun but other times just from being in a hot climate.Heat exhaustion describe the condition in which you become very hot and begin to lose water and/or salt from your body leading to feelings of weakness, dizziness, sickness and various other symptoms.

If heat exhaustion is not treated it can lead to heatstroke, which is when your body can no longer cool itself so your body temperature becomes dangerously high. This puts a strain on multiple organs including the brain, heart and lungs and can be life-threatening. If you have heatstroke, symptoms of heat exhaustion can develop into more serious symptoms like seizures (fits) and loss of consciousness.

If a person displays signs of heat exhaustion, you should try to cool them down by moving them to a shaded or air conditioned area, using a wet flannel to cool their skin and rehydrating them. However, the best advice that can be given is to not get heat exhaustion, heatstroke or sunburnt in the first place.

 

To ensure you are safe in the sun, you should spend time in the shade when the sun is at it’s strongest (between 11am-3pm in the UK) and use at least factor 15 suncream. Even if you are wearing water resistant suncream, it should be reapplied after you’ve been in water or if you’ve been sweating. You should protect your eyes using sunglasses with the CE mark and wear a wide-brimmed hat to shade your face and neck. Children are especially at risk as their skin is more sensitive than adult skin, so children should be encouraged to play in the shade, cover up in loose cotton clothes and wear lots of suncream. Finally, you should not spend a longer time in the sun wearing suncream than you would normally spend without it- my mum’s general rule of thumb is to limit it to 20 minutes of being in direct sunlight at any one time.

 

Whilst the sun does present some dangers, it’s warmth is also essential for human life to even exist and I still encourage you to enjoy it this spring and summer. All I ask is that you do so sensibly, because no sane person enjoys sunburn and heatstroke.