Sun’s out!

Get outside! It’s here! Quick before you miss it! There’s not been a huge number of warm sunny days but hopefully plenty to come. If you’re stuck at home this summer, you need to make sure you get outside as much as you can to get some warmth, a golden tan and some vitamin D. “Tan” is one of those words now used secondary to its original meaning as the verb, with the tanning of animal skins et cetera; so after the era when being pale and staying inside was popular, from the 1930s getting a tan was cool. Thenceforth the sun was our friend. Until a few years later when official advice was given about the damage the sun can do, increasing the likelihood of skin cancer. But let’s not get ahead of ourselves, we’ll start simple…

What is tanning?

Tanning is the process of darkening the skin colour by exposure to UV light. It involves a wee group of molecules called melanins. There are different kinds of melanins responsible for your skin colour and other coloured bits of you, like your eyes, hair, and lips. The lack of one kind of melanin with age results in those grey hairs and albinism is a condition where there’s no melanin present. Melanin is made by cells called melanocytes and then cells in the skin grab it and it sits around the nucleus to protect the DNA within from damage by radiation like UV from the sun. This explains why people living closer to the equator have darker skin as they are exposed to more UV than me, in Edinburgh, looking like a ghost! (And no, that’s not me confirming my belief in the supernatural – ghosts aren’t real…)

I won’t get too genetics involving melanin, mostly because I don’t like genetics; but a mutation has caused my eyes to be blue – lots of melanin = brown, less = green, little = blue. It’s more complicated than that but I don’t really know much more – like I say, I don’t like genetics.

504_Melanocytes
The epidermis – the top, outermost section of the skin.  Melanin is released from melanocytes at the bottom in little pods (vesicles) moving up the keratinocyte cells.  There’s far more melanin in darker-skinned people.

So tanning is all about melanin which is there to protect you; it’s a fine balance as I’ve experienced, you don’t want to be scarlet, accelerate aging or worse, be exposed to too much and maybe get cancer. For those not up on what cancer is: normal cells have a process of dying when they can’t function properly, like if DNA gets mutated (changed), and it’s stopped from making copies of itself by checkpoints. Cancer cells ignore this and keep going and dividing: they are your own cells but the code of the DNA has been changed – it won’t do its job! That’s why melanin surrounds the nucleus of the cell, stopping it being attacked. It sort of makes sense that if you’re pale and expose yourself to more UV light, you won’t have enough melanin to protect you properly.

Protecting yourself by covering up with your classy hat and sunnies works, then you’ll probably be slathering on that white coloured sun lotion. Sunscreens scatter and absorb UV light to different degrees, measured by how much longer than usual it’ll stop you being burnt. This is what that SPF (sun protection factor) indicates, so 15 SPF would protect you 15 times longer that without it. It won’t block 100% of UV light and with you moving about, sweating and diluting it, that’s why you’ll have that weird patch of burnt skin! So keep your lotion topped up, and look here for all the best advice on how to protect yourself in the sun.

The infographic below explains how sunscreens work, with the chemicals involved; also it defines the differences between specific forms of UV radiation.

Chemistry-of-Sunscreen.png

If you’re a bit pale and are tempted to get some fake tan.  This stuff wasn’t really a thing until the 1960s.  The effects of the chemical in it called DHA (dihydroxyacetone) have been known since the 1920s.  Its discovery for tanning was completely accidental in the 1950s when Eva Wittgenstein was trying to treat children with a glycogen storage disease when it spilled and stained the skin.  After research on this, the first tanning lotion was sold in the 1960s.  It works the same as the Maillard reaction which happens when meat browns when it’s baked/roasted. That doesn’t mean your arm will be nice and tender after, it only the top layers that naturally fall off that are affected, meaning you’ll have to top it up when the cells go and the tan fades. Have a look below to see the process involved.

Chemistry-of-Fake-Tan-2015-1

The ultimate consequence of being unprotected in the sun for too long is skin cancer. Cancer is a scary word, but the most common type of skin cancer is the most easily treated because it doesn’t like to spread. Melanoma is far less common but is harder to treat, it loves to spread (metastasise) and ignores a lot of treatments.  But even when I was writing this post, a new breakthrough was made by researchers in finding a way to make melanoma respond to treatments better.  So although there are aggressive cancers, there is research giving results every year that provides new targets for drug treatment that is taken advantage of; unfortunately, to ensure efficacy and safety it’s usually years before something is available for treatment.  There are some cases though, where there’s a similar drug that can help which does save lives.  You can find information about skin cancers more here and see the lovely image below which gives a nice summary of everything you need to know! Enjoy the sun but be careful – don’t look like a lobster!

Skin Cancer: UV Rays on the Rise
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The science of gin

Time for a drink? Maybe today’s one of those rare occasions where it’s not raining, perhaps it’s actually warm and the yellow thing in the sky makes an appearance. If it’s a pleasant evening then gin is what you need to match it. Gin and tonic maybe? Gin has had a huge renaissance just in the past five years; in Scotland alone there’s been a few brands gaining huge support and many more being set up. One of the main reasons for its popularity for producers is its relative simplicity and speed in making; many whisky distillers have chosen to make gin whilst they’re waiting at least three years for their batch to be ready. If you’ve ever been to a gin distillery you’ll have heard the history of gin, and it is quite interesting; the word itself coming from the dutch “geniver”. Living in Edinburgh it has also been interesting to learn about the local history of gin.

 

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All the different gins across Scotland – there’s quite a few!

To start making your gin, you need some neutral grain spirit. It’s the basic, tasteless, odourless highly pure alcohol used for making spirits like vodka and gin. They come from grain crops that are fermented. Next, you’ll need some botanicals: legally you’ll need juniper berries. It’s the most important and defining ingredient. They grow wild in Scotland but are protected; they’re often imported from other countries like Greece and various places in Europe, southwest Asia, and North America. Juniper is part of the pine family and that’s what it tastes like. It’s been used for hundreds of years for medicinal properties: diuretic, antiseptic, stomachic, antimicrobial, anti-inflammatory, and antirheumatic. They all come from an oil inside; specifically there’s terpinen-4-ol that makes your kidneys filter more, which will make you need the toilet more often (diuretic); there’s amentoflavone that’s found in a few other plants and has a number of properties like antimalarial and anticancer, as well as inhibiting enzymes that metabolise some drugs (in the liver). If you get cold sores a lot, chemicals called desoxypodophyllotoxins might inhibit the virus that causes them (herpes simplex virus) – so drink up! Or just use a normal cream that definitely works… Other parts of the berry – the resins are tars – can be used for topical treatments for things like psoriasis. A really useful little berry then. Find out more about Juniper

Other botanicals add depth of flavour, bind flavours together and add special characteristics. Coriander, angelica, citrus peel and orris root are common ones used. There are a few different ways to infuse the botanical flavours into the gin, the infographic below describes them. You’ll probably add a bit water at some point soon to help everything mix properly. It’s heated and the first to be cooled, the “heads”, aren’t pure and aren’t collected. The product will be about 80% pure, once the product falls under about 60% again it’s not collected. After it all, there will just be the water and what’s left of your botanicals. The stuff that’s not collected for the final product can be scrubbed and the pure alcohol recovered to use again. Your final gin will be roughly 40% ABV (alcohol by volume) if you’re going for Navy Strength, closer to 60% ABV. There’s a bit more to it than that but that’s basically it.

 

The-Chemistry-of-Gin.png
The molecules important in all gins

A good tonic water will complement your gin nicely; the quinine gives a bitter taste and balances it all nicely. Then once you’ve got your bottling and PR sorted, you can go ahead and sell your gin! To get your “perfect serve” you’ll need to match whatever botanicals you have with the contents of good quality tonic, then a garnish of fruit or herb that will complement it too. It really makes all the difference. So you can say it’s for medical reasons, or just because it’s just really refreshing, either way, have a gin. If you want a proper review of any gins, head over to Juniper Daze – Steph’s even got a gin of the month going on!

Ginfographic-2016

The science of cider

Now that we’ve all experienced at least one day of sun so far, I think it’s fair to start planning some relaxing days in the garden just soaking in the warmth, vitamin D and drinking a nice cold beverage. Such a situation calls for cider. The cold, crisp, sweet and fizzy drink is the perfect refreshment. It really is unparalleled in its ability to quench and relax on those warm days. Sure there’s beer but I don’t like beer. There’s wine, but you need a lot of liquid to replenish and feel satisfied. Maybe a cocktail if you can be bothered with all the faff, or a long spirit based drink for a simple solution. But cider, oh cider. It has a complexity of flavour that makes you feel as though you’re drinking something special. You can just sit with a nice pint and feel like you’ve achieved in your life. In hindsight, this post should really have been sponsored by a cider brand… but ah well, I’m new at this.

Away from my self-indulgent delusions of being an eloquent advertiser, let’s get down to some definitions to get us started. Cider is basically fermented apple juice maybe some sugar; usually, there has to be a specific percentage of apple juice to call it cider. Fermentation involves yeast and sugar which provides alcohol (ethanol specifically) and carbon dioxide.

From the beginning then, you get some apples. Good start. It’s not usually your bog-standard apples though, it’ll have to be ones that would normally not be that pleasant to eat. Have you ever tried a crab apple? Different properties make apples more suitable for fermenting – if they are particularly acidic, sugary and high in compounds called tannins (bitter and astringent tasting compounds). Once you have your perfect apples and maybe some extra ones to add sweetness at the end, you need to get them pulped and pressed to get out the juice. If you filter it, it’ll be a clearer cider, or leave it for a cloudy one, depends on what your preference is. Next to ferment it. It would happen by itself by natural yeasts just in the air, but that not very predictable – who knows what kind of cider you’d get from that. Predictable fermentation would use a yeast like Saccharomyces bayanus which is the most common for wines and ciders, you can buy it pretty cheap, just like bread-making yeasts (Saccharomyces cerevisiae for bread, by the way). If you want a dry cider, leave the fermenting going until all the sugars have been used up, otherwise take out the yeast a bit early for a sweeter taste. This is done at pretty low temperatures, colder than room temperature, which is unusual since yeasts like things a bit cozier at maybe 30 degrees. But this low temperature makes things happen a bit slower which seems to benefit cider getting the best out of your apples. You’ll need to leave it a while to mature, all the flavours develop and you can add any extras like fresh apple juice if you want to mix things up a little. Bear in mind adding more sugar to make it sweeter would probably start the fermenting again so you could add artificial sweetener. I’d just keep it natural and see what happens. With all your carbon dioxide being produced it should have some fizz once you bottle your cider, then you can get it chilled and enjoy! Phew. It’s not that complex a process but a lot of tweaks to make to get the taste you’re looking for. See the infographic below for a nice summary of the process and all of the molecules involved in making a tasty fruity pint.

The-Chemistry-of-Cider
The main molecules involved in a pint of the good stuff
The UK is arguably the best place to get a good pint of cider. There’s a lot of big brands and the recent resurgence in popularity means there’s even more choice from loads of smaller brewers. We’re pretty lucky. Everyone’s got their preference, I’m not too keen on a dry cider but it’s got to have plenty flavour. Magners is probably what I’d aim for, the right balance I think. And as I’m sure all the purists will tell you: if it’s not apples, it’s not cider. If it’s pear it’s perry and if it’s any other fruit, alcoholic fruit wine?

THATCHERS_A4_APPLE_TABLE
Example of the variety of apples used in making cider
Unfortunately, if you’re going to drink alcohol and be diabetic, cider probably shouldn’t be your first choice. With all the sugar it’s not to treat you nicely. Up to five teaspoons of sugar are in a pint of cider and not much other nutritional value just calories. There are some antioxidants in cider, about the same as in red wine; I think antioxidants are overrated but they do have value and a genuine function in the body clearing up toxins. With all that sugar though there’s not really much benefit from it: it’s bad for drinking if you are diabetic and drink too much and it could make you diabetic. If you’re drinking responsibly though it’s not too bad. If you are gluten intolerant at least cider is a tasty drink.

sugar content
A few (albeit American) examples of the nutrition of cider compared to popular beers
Below you’ll see an informative wee graphic describing the effects of alcohol on the organs and how alcohol is processed. It’s well known how alcohol can affect the liver and this is because it’s the main site of alcohol metabolism. There are a few enzymes that deal with alcohol and it gets metabolized into something toxic in the first place, but then quickly into something that can be broken up to get rid off. Of course, these enzymes can only work so fast and the alcohol in the bloodstream starts to inhibit brain function, starting from the back. That’s why you get disorientated and stumble as the alcohol gets into the medulla, cerebellum then the big bit, the cerebrum as the alcohol starts affecting the senses, slowing down processing of information we get from the eyes, ears, and nose. Movement slows and responses slow as alcohol hits the motor cortex and then memories in areas like the hypothalamus until you eventually black out as basic processes shut down. The area of the cerebrum controlling behavioral inhibition is affected making most people more social… although some are just annoying. Alcohol affects a lot of processes in the brain, the chemistry of the brain can change dramatically in the presence of alcohol. When you’re taking benzodiazepines they work by increasing the effect of the inhibitory system of the brain – a chemical called GABA. It promotes sedation and relaxation. So when combined with alcohol it can relax you to a dangerous level when heart rate decreases a bit too low to do its job and pump blood enough. I think we all know how important pumping blood is…

http://visual.ly/how-alcohol-travels-through-body

So when you’re relaxing in the sun this summer, just think what that pint of cider is doing to your brain and how it was made. By this point, you’ll probably have lost your inhibition and will explain it all to your friend!

Disclaimer: please always drink sensibly – get some good info at Drinkaware

A horrible life with histamine

It’s that time of year again. As the sun comes out and shines, plants and trees come into blossom. Beautiful… and causing pain for millions. Summer is somewhat oxymoronic for me: it’s great looking at the weather forecast to see it’ll be sunny tomorrow, opposed with the dread of seeing the pollen count will be anything other than “low”. Seasonal allergic rhinitis or hayfever can be a nightmare, ruining that rare opportunity to get some much-needed vitamin D. First thing in the morning with itchy eyes, tickly throat and runny nose – brilliant. Having said that, I don’t only get these symptoms in the summer, there have been a few Christmases when I’ve had itchy eyes; I’ll blame the turkey. It’s always worse in the summer though, I’m glad I managed to get medication on prescription, otherwise, it’d be an expensive inconvenience.

The whole thing is caused by our fantastic immune systems overreacting to something which is actually innocuous – it’s nothing that’s going to do harm. The body attacks it with everything it’s got, trying to get rid of it.  Mucous membranes leaking left, right and center making eyes and nose stream, itching to get us to scratch it all away, sneezing to expel it – like having a cold in the middle of the summer. It’s definitely more prevalent in recent generations, maybe I wasn’t exposed to enough dirt and fields as a child. Although that’s not my parents’ fault, I didn’t like getting dirty – always a well-presented child. Nothing’s changed much…  I know far more people my age and younger that have hayfever and other allergies than I do my elders.  Maybe my compromised immune system makes me more susceptible? A new area of research I’m sure I’ll get round to one day.

So billions of tablets, sprays and whatever else they’ve come up with this year are being sold to combat this summer destroyer. The culprit – histamine. This little molecule is usually pretty useful, but no… it’s turned against us. Histamine is made by cells of the immune system, hidden in connective tissue. It opens up the tiny blood vessels (capillaries) to make them more permeable to their pals white blood cells (leukocytes) who would normally do the business of destroying invaders. It’s got loads of functions around the body but it helps make the body more sensitive to itch (hypernociception) and get things nice and inflamed to let more of those lovely white blood cells get to work. None of this is useful when pollen goes up your nose, ends up binding to white blood cells sending out antibodies which bind to a fun mast cell which releases histamine and begins that familiar set of symptoms. For some, that increased itchiness even means a lovely red rash – thanks, histamine!

histamine
The main culprit – this small Histamine molecule.
Antihistamines for allergies are aimed at those receptors on mast cells that cause you to feel rubbish. Cetirizine, loratadine (Claritin) and chlorphenamine (piriton) all work at this receptor – H1. They all work differently to try and stop the receptor telling the cell to release it’s histamine stores. The trouble with drugs generally is the myriad functions each receptor has: each receptor could have multiple functions both wherever that cell is, but other kinds of cells may also have the same receptor somewhere else for something completely different! This is why drugs aim to be a specific as possible to a receptor and a location. You’ll have heard of side-effects – being as specific to a receptor as possible decrease these effects around the body. In the case of antihistamines an example is that histamine in the brain acts to regulate sleep and wakefulness, so stopping it here causes drowsiness.  It’s the same pathway I was chatting about last week. The brain isn’t connected to the bloodstream like most other parts of the body, there’s a thin barrier – the blood-brain barrier cleverly named. It means only certain things can cross over that meet specific criteria. So you design the drug that it doesn’t meet those criteria. A simple concept, but drug discovery and design are definitely extremely difficult. Sometimes that’s why a drug is chosen to be specific to one particular area, by controlling how it is administered. If you’re taking a tablet, the hope it that it gets into the bloodstream which goes all around the body. That may mean only a small concentration of the drug gets to where you need it if your target is really common. For antihistamines nasal sprays and eye drops are a good example; they get to where they need to go, limiting the side effects and usually do their job quicker.

 

That’s the point of antihistamines, but they’re far from ideal and don’t work to stop symptoms 100%. Of course, there are many types of antihistamine because there are other types of histamine receptor elsewhere with other functions, so they’re not only given for allergies. But a similar inflammatory response is seen in the common cold, which I find helps, but there is only weak evidence to show this actually is effective – so perhaps it’s just a placebo effect with me. An extreme treatment for extreme symptoms would be immunotherapy. This involves giving the body small doses of the specific problem allergen, e.g. grass pollen, weed pollen, in small doses over a long period. It essentially trains the immune system to recognize it as harmless. This has been a treatment for a while and commonly involves trips to get injections on a regular basis. Recently there’s been a tablet that dissolves under the tongue (referred to as sublingual by the way) which is a quick way into the bloodstream; it still involves the long-term training of the immune system but makes it easier to use. It’s just grass pollen extract – the bit that the antibodies would be attacking the help the body get used to it. Clever stuff!

death star pollen meme

When drugs have failed and before the time of the pharmaceutical industry, nature has always provided a helping hand. Vitamin C is a known antihistamine and things like chillis, garlic, honey, and carrots can all help the symptoms like congestion, or protect your body in the first place. Capsaicin for example found in chili peppers helps to decrease congestion as well as garlic. Carotenoids found in carrots, pumpkins, sweet potatoes and others are antioxidants that can be anti-inflammatory. As in many drugs, nature provides a solution. Not that natural remedies are necessarily better, but if they work, obviously it’s worthwhile. I’m sure that’s a debate for another time.

I don’t think I’ll ever win the war against hayfever but it’s ruined so many summer days so far, I’m willing to fight it. I’ve found wearing my contact lenses actually helps if I can get them in quickly enough; sort of makes sense if they form a barrier, but then the pollen still gets breathed in so the other symptoms still occur. It’s been better though, so that’s one battle won. I’m taking Piriton (chlorphenamine) which works best before symptoms occur and I have few side effects, definitely no drowsiness. The side effects seem to decrease as the body gets used to the drug. Usually, it’s too late for the drug to be most effective – itchy eyes are my worst symptom and the first, as soon as they twitch, I’m running towards the tablets! The war continues then: timing it right, maybe researching when it’s going to be a bad day, research will always help to understand allergies and how to better combat them, especially for the worst affected. Trying to suppress the immune system can never be a good thing, it’ll leave you open to goodness knows what else, but I don’t think the drugs last long enough in the body to do anything. Maybe over a longer time, there would be an effect – taking any drug for years is going to result in some sort of unwanted effect. So that’s how the drugs work, and maybe you’ve learned something – so go away and dry your eyes, tomorrow might be a low pollen day…

Here’s more info and advice or if you fancy some more reading (very sciency)

Here’s a quick video for all you visual learners and the infographic below for a nice summary of the facts.

Disclaimer: please don’t be taking any drugs just because I said they work, I’ve been prescribed them. There are pharmacists and GPs for a reason – seek medical advice, especially if you have a pre-existing medical condition.

Hay Fever; You Really Get Up My Nose!