Planet-Friendly Gardening

I have long been interested in reducing my impact on the planet, not least when gardening. I became a serious gardener in the 1980s when climate change was just entering into the public consciousness and a cold winter would conveniently put everyone’s minds at rest about global warming. My neighbour two doors away proudly boasted of all the peat she had lavished on her garden, and it was indeed lush and orderly. Years later, I still haven’t forgotten the deep discomfort I felt at this situation. Why should I judge my neighbour for wanting a beautiful garden and for spending large amount of money on bags of peat to achieve it? Deep down, I wanted to rant about the damage to irreplaceable peat bogs, but I was aware that I had also bought bags of compost containing peat. And I didn’t want to fall out with my neighbour. There was very little choice in those days, apart from making your own, which I did.

Nearly forty years later, I wonder how much has changed. I let my eco-crusade progressively slip as I focused on my career, relationships and caring for a family. Last year, after all this time, Monty Don began promoting the use of peat-free compost. I went to my local nursery and asked them if they would consider stopping the use of peat-based compost, and they said they would if everyone else did, otherwise they would become less able to compete on price. Peat-based commercial compost still seems to be the industry standard, although the alternatives are now more widely available.

I’ll come back to peat and compost later, as there is plenty more to say, but I have used it as an example of how the gardening industry can perpetuate damage to our planet, and to make the point that a well-informed consumer can make a difference. There is so much to being a planet-friendly gardener, and I will organise this blogpost around the principles of being a ‘green consumer’ –  ‘Reduce, reuse, recycle’ –  along with information about garden habitats for the organisms we share the world with.

Being a planet-friendly consumer

1. Reduce

The idea of ‘reduce’ is to ask yourself, Do I really need this new piece of equipment? Do I need to buy this bag of compost? Do I need to use these chemicals? Do I need to buy new plastic pots? Even peat free compost can come in plastic bags and takes energy to transport. It’s important to say that I am not against the use of plastic until practical replacements come along, but we gardeners can easily end up with a shed bulging with empty plastic bags and broken pots that we are loathe to throw out because we know they won’t be recycled. The first principle has to be to reduce our demands on the planet’s finite resources.

Some products have less impact on the planet’s finite resources because they are made from renewable resources. Plant labels can be made from wood or bamboo and plant pots can be made from plant fibres, commonly coir, paper, and sometimes composted cow manure. You would pay a lot more for these products than the equivalent plastic ones, and their lifespan is shorter, mainly because they are biodegradable.  For UK consumers, coir may be less desirable as it comes from coconut and has to be shipped some distance. Beware of the biodegradable pots made with peat!  Peat is not a renewable product, unless you are working on a 500+-year cycle. Peat bogs play an important role in storing carbon and more than ever, we need peat bogs to be left undisturbed and restored.

Reducing the use of chemicals is something everyone can do. Consumer regulations have tightened recently, meaning that it will soon be against the law to sell or use metaldehyde slug pellets in the UK. This is good news for our wildlife. Although the alternative, ferric phosphate, will still be allowed, these pellets contain chemicals that are harmful to earthworms and can also harm mammals in large quantities, so are best avoided. Insecticides and herbicides are rarely necessary in gardens, and there are plenty of other measures that can allow gardeners to exist side-by-side with nature rather than club it with chemicals. Artificial fertilisers are chemicals too. They can upset the soil ecosystem and affect soil structure. The production of garden chemicals uses energy and creates greenhouse gases as by-products. A far more planet-friendly way to look after your plants is to look after your soil by applying compost. More on this later.

Another way of reducing your product consumption is to make your own compost.  Some of the best advice I have come across is from Charles Dowding, and you can see one of his videos here https://youtu.be/BIV4lljN6Aw .   Making your own may not meet all your needs, but will reduce the amount you need to buy.

2. Reuse

Reusing is one of the easiest and most cost-effective thing gardeners can do.  If you can re-use your plastic pots and propagation trays year on year, you are limiting your consumption of the earth’s finite resources. As long as you keep on using them, you are keeping them out of landfill and you are not replacing them with more. You don’t really need to wash your pots either, so you can save on water that way.

In our neighbourhood, the gardening club organises plant stalls where gardeners bring plants they have propagated and buy plants that others have contributed. This is a type of re-use, where plants and their pots go to a new home. The local hardware shop takes unwanted pots off people’s hands and re-uses them, and sometimes gardeners will leave empty pots outside to be picked up and re-used by other gardeners who are in need of them.

I have used pots as an example, but you’ll be able to think of many more items that can be re-used or given a new home through in addition to other objects such as washing machine drums or old baths and sinks.

3. Recycle

Some garden products are made from recycled plastic, which is good because it is keeping plastic out of landfill. These products can include watering cans, garden planters, raised beds, and benches. It may be less easy to find ways of recycling your broken plant pots if you live in an area where they are not collected from the kerbside. Black pots are the most challenging because they are not detected by the sorting machinery in recycling centres. If there is no kerbside collection where you live, ask your local nursery whether they are able to take pots for recycling.

As for the compost bags bulging out of garden sheds, many people find ways to re-use them for other purposes, but there probably comes a time when they are too tattered to be of any use, or you just have too many. You might want to try giving the good ones away in case someone else as a use for them, or find a place where they can be recycled. Check out the bag recycling scheme at your local supermarket – you might be surprised at what they will accept, although you’d probably have to give your compost bags a good wash. There is also general advice available on recycling plastic bags.

Looking after the soil

So far, I have considered the consumer side of being a planet-friendly gardener. I’d like to focus on the garden itself now, starting with the soil.

Soil is a rich habitat, which in the recent past was poorly understood. Soil life ranges progressively in size from microorganisms that can only be seen through a powerful microscope through to larger organisms easily visible to the naked eye, such as slugs, millipedes, beetles, earthworms and small mammals. Soil organisms rely on a supply of dead organic matter (both plant and animal origin) to fuel their food web, although some will eat other living soil organisms. This is similar to the interdependence you would see in food webs above ground.

As a gardener, you want to optimise your soil for growing plants. Plants need the mineral nutrients found in soil to support their metabolism, and obtain their fuel by converting atmospheric carbon dioxide to sugar by the process of photosynthesis powered by sunlight. Plants also need a supply of water to take in through their roots along with the minerals. Waterlogging can damage some plants and very dry soils can cause wilting and eventually death of a plant. A good soil structure can help to maintain good water drainage as well as encourage water retention in a dry spell, and this is where it helps to cultivate your soil organisms. Look after your soil, and the soil will look after your plants!

These are some of the ways soil organisms promote healthy plants and gardens:

  • By ingesting and breaking up organic material such as dead animals, leaf litter and other dead plant material
  • Making the nutrients within organic matter available for re-use by other organisms including plants
  • By creating physical spaces within the soil that allow aeration and water drainage. Air in soils allows plant roots and soil organisms to ‘breathe’.
  • By distributing the organic matter, which can absorb and hold water

‘Mycorrhizal fungi’ have become very popular products in gardening circles lately. In nature, mycorrhizal fungi co-exist as tiny strands networked through the soil, living in symbiosis with plants. The fungi benefit from the sugars exuded from the plant roots and in return, they extend the plant’s reach into the soil by channelling water and minerals towards the root and aiding absorption. Digging the soil and adding chemicals can upset the soil ecosystem, which is one of the reasons we have become so dependent on fertilisers. Fertilisers themselves can contribute to this damage, so perpetuating a cycle of dependency. We return to the mantra: ‘Look after your soil, and the soil will look after your plants!’

The image here provides a useful overview of the symbiotic relationship between plants and micro-organisms
Hallrob3, CC BY-SA 4.0, via Wikimedia Commons

The solution I’m proposing is very simple.  By not disturbing the soil and by ensuring a good supply of organic matter, you are doing your best to care for your soil and your plants. Instead of digging the vegetable patch, simply add a layer of compost each year. Smother perennial weeds with a light excluding mulch such as cardboard, or black plastic. You can re-use the plastic elsewhere afterwards, and the cardboard will rot down in a few months. Hoe annual weeds when they are small, only grazing the surface.  The same principles apply to a flower garden.  Always think of yourself feeding the soil rather than the plants.

Making compost

You can buy compost, but it comes at some expense to you and the planet, especially if it arrives in plastic bags. There is also the environmental cost of transport.  I’ve already mentioned the advice supplied by Charles Dowding , and Monty Don provides useful information too. Most gardens are on a much smaller scale than you’ll see in these videos, so don’t be discouraged by that.

Welcoming wildlife

‘Gardening for wildlife’ is certainly a popular discussion topic nowadays. You’ve already thought about being good to the wildlife in your soil. All the other creatures that will potentially visit your garden will appreciate any shelter, food and water you can provide. Translating welcoming wildlife into an aspiration to be a ‘planet-friendly’ gardener takes some further thought. Perhaps the most useful way of looking at it is to consider how you might promote biodiversity and replace some of the habitats that are becoming scarce.

Gardens are becoming havens for amphibians and reptiles as their wild habitats become scarcer.  According to the Amphibian and Reptile Conservation Trust creating wildlife ponds and log and brash piles, allowing lawns to grow long, and the use of roofing slates or paving slabs as reptile refuges are helpful strategies. If you are aware of grass snakes favouring your compost heap as an egg-laying site, do not disturb from June to September. A more in-depth treatment of the topic is available from ‘Hazelwood Landscapes’

Some birds have become familiar garden visitors. The provision of food, water and shelter for birds in gardens has boosted the numbers of certain species in the UK, for example, goldfinches.  The story is not always so positive. Greenfinches have declined dramatically, thought to be due to the disease finch trichomoniosis picked up at bird feeding stations. Although garden feeding clearly affects bird populations, it is still unclear how this would impact more widely on ecosystems. The most useful advice I have found for protecting birds is to clean feed dispensers regularly, along with not disturbing nests during the breeding season.  The British Trust for Ornithology has more information. As natural nesting sites are disappearing, it can also be helpful to provide nest boxes

A hedgehog foraging amongst fallen leaves

Photo by Piotr Łaskawski on Unsplash

In the UK, hedgehogs are much-loved and also in serious decline. Their decline could be an indication of decreasing quality of the UK ecosystem, such as loss of hedgerows and permanent pastures, and the use of pesticides. Therefore, doing your bit to provide some hospitality to hedgehogs can go some way to support their populations until, perhaps, hedgerows are restored in the countryside. In urban areas, gardens are even more important as habitats for hedgehogs. There is some very good advice issued by ‘Hedgehog Street’, a partnership project between the People’s Trust for Endangered Species (PTES) and the British Hedgehog Preservation Society (BHPS). Hedgehogs can benefit our gardens by consuming some of the insects and other soil invertebrates that eat our plants. By caring well for your soil, you can help to care for hedgehogs too.

What do you consider to be planet-friendly gardening practices? Leave a comment below!

Histamine – the enemy within for allergy sufferers

IMG_20170619_074520313

You probably know someone who suffers from allergies that result in hayfever, asthma or urticaria. It could be you. The recent heatwave in the UK has caused huge discomfort for many such allergy sufferers. A period of rain allowing lush grass growth followed by the heat has given rise to a perfect storm of airborne pollen. Antihistamines are the main pharmaceutical remedy for allergies, and I imagine they are flying off the supermarket shelves as I write. Cetirizine, Loratadine, and Acrivastine are types of antihistamine readily available in the UK.

But have you ever wondered why ‘anti-histamines’? Why is histamine such bad news for allergy sufferers, and why do our bodies produce it if it wreaks such havoc? Well, actually, our bodies need histamine for normal functioning. Histamine plays an essential role in protecting the skin, airways and digestive tract from invaders such as parasites, bacteria and viruses. It also acts as a chemical messenger in the brain, helping to keep us alert. Additionally, histamine helps to stimulate the release of stomach acid. Histamine’s role in fighting the invasion of harmful organisms and initiating tissue responses to damage is what affects so many allergy sufferers.

Photo of airboorne grass pollen
Airborne grass pollen

Mediator of protection and healing

If you cut your finger or inhale a virus into your air passages, your body needs to supply extra blood to those areas to bring in the necessary ‘weapons’ and healing substances. Release of histamine, which is stored in ‘mast cells’ in the skin and mucous membranes, makes the tiny blood vessels dilate, allowing more blood into the area. The walls of the tiniest blood vessels, the capillaries, become more permeable to allow protective white blood cells and fluid to pass into the tissues. They become ‘leaky’. This leakiness means that tissues swell with extra fluid and blood cells. In the skin, this appears as swelling and redness. In the airways, there is congestion and watery mucus appears. Itching and sneezing can occur from stimulation of nerve endings.

Histamine molecule
Histamine is a small molecule made of three nitrogen, five carbon and nine hydrogen atoms.

Harmless substances taken for pathogens

When someone has an allergic reaction, their body interprets harmless substances such as pollen as being pathogenic. At some point in the past, their immune system has become sensitised. The hygiene hypothesis proposes that children in the developed world have insufficient exposure to a wide range of harmful organisms, and a relatively ‘idle’ immune system targets harmless substances instead. Allergic reactions are most closely aligned with the mechanisms for fighting parasitic invasions, in which there is a massive release of histamine in the affected tissues.

In allergic individuals, then, histamine feels like the enemy within. The itching, soreness, sneezing, coughing and wheezing evoked by histamine release cause extensive misery, and in extreme cases an allergic reaction can be fatal.

Anaphylaxis

In extreme cases, histamine release can be deadly. If you have a severe allergy to wasp or bee stings, certain medications, or foods, for example, it may cause anaphylaxis. Overwhelming levels of histamine are released into many parts of the body within a very short time. Skin breaks out in urticaria, the mouth and throat swell, airways constrict. Rapid leakage of fluid from the capillaries into these body tissues can cause a fall in blood pressure, leading to fainting. All these effects combine into anaphylactic shock, which is life threatening. The main lifesaver is an injection of adrenaline, which counteracts the most damaging effects of histamine. You may be interested in this informative video featuring Anaphylaxis Campaign Professor John Warner OBE:
https://www.youtube.com/watch?v=rlMYStReFL8

Mast cells

A discussion of hayfever feels quite mundane after contemplating anaphylaxis! It is worth taking a closer look at the mast cells before a final thought about antihistamines. Mast cells are made receptive to allergens (which act as antigens – something that triggers an immune response) by antibodies attaching themselves to the cell. Once triggered, the mast cell releases histamine into the surrounding tissues. Most of the time, this is a local response in the air passages or a certain place on the skin. In anaphylaxis, mast cells are triggered on a large scale.

A diagram of a mast cell
A mast cell releasing histamine (diagrammatic)

The blood-brain barrier

You remember I mentioned that histamine acts on the brain to help us stay alert? Presumably, then, antihistamines interfere with this? I remember as a child feeling privileged that my GP took the trouble to explain to me why the antihistamines I was taking made me feel sleepy. Luckily, for those hayfever sufferers nowadays who drive or operate machinery or are doing exams and so on, pharmacologists have developed modern antihistamines to minimise the effects on the brain. They have taken advantage of something known as the ‘blood-brain barrier’, identified in 1913. Modern antihistamines are barely able to pass from the blood into the brain through the blood-brain barrier, and therefore have almost negligible effects on a person’s wakefulness.

It’s quite a simple idea to grasp, although very complicated in detail, and still the subject of intense research. In short, the blood-brain barrier is a unique physical and chemical structure in the body that keeps the majority of the substances carried by the blood out of the brain. It will allow, for example, glucose, oxygen, amino acids, hormones and anaesthetics to pass through, but not antibodies, toxins and bacteria. Although alcohol can be considered a toxin, it is small enough to slip through the blood-brain barrier. If scientists could prevent alcohol passing into our brains, I wonder if this would increase or decrease our consumption?

I wish all you allergy suffers some respite from the sneezing, itching and wheezing this summer!

Photo of grass
A grass head laden with pollen

What kind of bread should you eat?

A sceptical approach to commonly held attitudes and beliefs

I took part in a fascinating discussion at a conference a few weeks ago. The conference theme was ‘What shall we eat?’ with the parallel theme ‘how shall we grow our food?’ The speakers were excellent. One of the workshops I attended was exploring attitudes towards food, in relation to production methods.

During the workshop, the facilitators handed around two bread samples from a white sliced loaf and an artisan loaf. The overwhelming consensus was that the artisan bread was healthier – a ‘no brainer’ as far as healthy food choices are concerned. Who with any sense would choose a white ‘factory’ bread over the artisan option? It got me thinking about people’s values regarding food. What drives our choices?

artisan-bread
Spoilt for choice

These are some of the attitudes shared in the workshop:

Artisan bread is more filling and satisfying/ more nutritious / better for the environment/ supporting small producers/ contains natural chemical-free ingredients

I felt increasingly uncomfortable. How much choice do most people really have? For me, these attitudes smacked of food snobbery. (TV presenter Greg Wallace gives his own take on food snobbery.) Do ‘natural’ food campaigners sometimes lose sight of the overwhelming social and financial issues that restrict food and lifestyle choices? But more importantly, is artisan bread really that much better for us?

Is artisan bread more nutritious?

As a result of this discomfort, I feel compelled to check out the bread facts. To what extent is artisan bread healthier than mass-produced sliced white bread? Let’s start with the nutritional content for protein, carbohydrate fat, energy and dietary fibre. In the cold light of day, there is actually very little difference in the macronutrient content of white bread and artisan bread.

bread-nutrients
Figures derived from http://badges.myfitnesspal.com/food/calories/93175308 and https://www.gov.uk/government/publications/composition-of-foods-integrated-dataset-cofid

So, what about the micronutrients? A scan of a range of sources reveals that the differences in the levels of thiamin, niacin, riboflavin, iron and calcium are negligible, although they might be slightly lower in white bread.

Is artisan bread easier to digest?

In my investigation of bread and health, I found an article by Jamie Oliver.  In it, he states that ‘Artisan bread is actually easier to digest, because the enzymes have had time to begin breaking down the gluten in the flour while fermenting’. This is  news to me, and I want to find out more about the breakdown of gluten in the bread-making process. And what about the claim about this making the bread more easily digestible? I need to find out!

It’s quite hard to get beyond the rhetoric about gluten. If you believe the vast majority of web chatter, gluten is a very bad thing indeed. I accept that evidence is building of adverse human responses to gluten. There are plenty of science-based articles pointing to the dangers of gluten. Despite referencing their sources, even here there seems to be some misinterpretation of the science, and I’m looking for the bare facts.

I feel a bit more comfortable with the standard of this article written by Jake New, as it draws directly from original science and doesn’t make over-inflated health claims. Jake explains how the gluten proteins can be incompletely broken down. Some people develop an inflammatory response to the resulting polypeptides (partially digested proteins). I’m still no further in discovering whether the preparation method really does makes the gluten in one bread easier to digest than another. What a pity Jamie Oliver did not give a reference for this claim! The only way I know to resolve this is to read the scientific papers, and particularly any systematic reviews of the research on gluten and health.

According to a systematic review by Smith et al (2015), about half the protein in wheat comprises gluten. Importantly, the authors stated that research into gluten digestion is conducted using test tubes. It is not particularly straightforward to extrapolate these findings into what actually happens inside your stomach and intestines. This aside, in their experiments, they found that baking markedly reduced the digestibility of the gluten proteins, compared with flour. They also found that the gluten proteins in bread are hardly broken down at all by the stomach enzyme pepsin, but that the enzymes normally present in the small intestine were effective in digesting gluten.

I cannot find anything discussing the baking method with respect to gluten digestibility, although I do feel more knowledgeable about gluten composition and digestion.

This New Zealand site created by the Baking Industry Research Trust explains a number of useful facts about bread and gluten. It confirms what I thought – that fermentation involves the breakdown of starches to produce the gas carbon dioxide and alcohol. I have found no sources explaining how fermentation might break down gluten. It explains that the proteins gliadin and glutenin combine during the bread-making process to form gluten, which does not otherwise exist in this form. According to another source,  the fermentation process also produces lactic and acetic acids, which add to the flavour.

To summarise, this is what I have discovered so far:

Wheat does not contain gluten – it contains two proteins, gliadin and glutenin, that combine during the bread-making process to form gluten.

The part of gluten that causes allergic responses and intolerance is gliadin, after the gluten has been partially digested into glutenin and gliadin.

The gluten in bread is much more difficult for human digestive enzymes to break down than the separate proteins found in flour. This seems to happen in the duodenum rather than in the stomach.

In artisan baking, the gluten undergoes repeated, slow cycles of stretching and relaxing, during which time the starches and sugars in the flour ferment into carbon dioxide, alcohol, and lactic and acetic acids. The liquid by-products contribute to the tastiness of artisan breads. It isn’t clear where the claims about the gluten becoming more digestible originate from.

Does artisan bread contain fewer harmful chemicals?

The UK Flour Advisory Bureau provides a helpful guide to the additives commonly made to flour. For bread, they might augment the enzymes that are already naturally present. To improve the texture and structure, they add Vitamin C and sometimes the amino acid cysteine (which is a necessary component of our body proteins and can be made by our livers). All flours except wholegrain are also fortified with B vitamins and calcium. And so far, I’m not worried about the chemicals in mass produced bread.

But what about pesticides? This is a complex topic and one to put aside for a follow-up blog article!

What kind of bread will I eat?

I have reassured myself that as far as nutrition is concerned, the type of bread I choose makes little difference. It’s far more important to consider diet as a whole. There will be times when I want to splash out on an artisan bread as a treat, and also when I want to support my local breadmakers. What bread choices do you make and why?

How bad can foot eczema be?

shoe-1029734_640I remember hearing a woman interviewed on the radio a few years ago. She was claiming income support (welfare) and lamented that she was unable to attend job interviews because she was allergic to shoes. This was at a time when the press were vilifying any unemployed people who appeared ‘undeserving’ of welfare payments. In the prevailing mood, it was difficult to accept the foot condition as a valid excuse.

At the time, even though I had already succumbed to severe hand eczema, foot eczema was just an abstract idea, something for my imagination. I felt thankful it was only on my hands, bad as that was. But I did develop eczema on my feet, and it was only a matter of months after that radio interview. And it turned out, I had become allergic to my shoes.

IMAG0847-adjusted-small
Foot eczema

It was bad. The itching was intense. Tense blisters appeared, making it impossible to put shoes on. I had to sleep with my feet hanging over the edge of the mattress, as I couldn’t stand even the weight of my feet on the bed.  I was thankful that I was able to work at home for several days, as it was impossible for me to leave the house.

Eventually, I had some patch testing. It revealed that I was allergic to two rubber accelerator chemicals (vulcanisers), which commonly occur in the rubber found in the soles of shoes. I still remember studying the vulcanisation (creating a polymer) of rubber in A level chemistry.  These substances can also be found in the adhesives used in joining leather.  As shoes become worn in and are exposed to moisture, the chemicals leach out and come in contact with the skin. Step number one – know your enemy!

Translating chemical names into which shoes you can wear is something else entirely. Shoes don’t come labelled conveniently with things such as ‘contains thiuram chemicals’ or ‘contains carbamates’. The dermatology advice was to ‘wear all-leather shoes with no inner sole (like moccasins), plastic shoes or wooden clogs. If you have difficulty acquiring shoes without rubber insoles, remove the insoles before wearing and replace with those cut from piano felt, cork, or plastic.’ Try going into a shoe shop and asking what their insoles are made of! Try removing the insoles from women’s shoes.  As I suspected that simply sweating was also a likely factor in my eczema, I was keen to avoid plastic shoes too. The advice was also to discard old socks, as they can harbour the harmful chemicals.

I bought some wooden clogs online, and discarded all my socks. Hobbling around with my sore, bare feet (not yet able to go sock shopping) in wooden clogs, I began my campaign to find wearable shoes.

SatraFootwearI contacted Satra Technology, a company based in Kettering, UK, known as a ‘leading technical authority for footwear and leather’. They advised me on alternatives to leather or plastic soles. Interestingly, thermoplastic rubber (TR) and crepe are not vulcanised, so they were safe. Also, I could look out for polyvinyl chloride (PVC), polyurethane (PU) and ethylene vinyl acetate (EVA) soles. Try going into a shoe shop and asking what their soles are made of.

Some shoe retailers were more helpful than others. I was very relieved to find that my recently acquired Trespass walking boots could get the thumbs up – the only rubber component was the outer sole – the midsole and insoles were fine. I discovered that many shoe manufacturers source the leathers and various components from all over the world. It was almost impossible for them to vouch for the exact materials used, especially the glues. Even craft shoemakers relied on glues/cements to keep their leathers in line.

The only assurance I could obtain on leather adhesives was with Gore Tex.  Clarks informed me that glues were not used in joining the uppers and linings of Gore Tex shoes. I was also very thankful when I found Easy Wellies, who made it extremely easy to search their stock for PVC boots and garden shoes.

I eventually had to give up on asking about the cements in leather shoes. My life was slipping away week by week, with one manufacturer after the other unable to give assurances on this. I was becoming tired of existing in PVC wellies and wooden clogs (and my hefty walking boots).  Step number 2 – avoiding the enemy – was proving very hard.

These days, my first stop for shoes is Hotter. Many, but not all, of their styles use polyurethane for soling. Yes! Quite a few of their styles contain elastic (made with rubber?), so I avoid those. Their customer services department is very helpful and will bend over backwards to research the various materials in their shoes. I buy their leather shoes on the understanding that one day I might have a reaction to the leather cement, although apparently they use it sparingly. I just try not to sweat.

Is ageing inevitable?

I started writing this article when ageing was again in the news, this time in connection with shift workers. We have mounting evidence that working night shifts can accelerate ageing and decrease longevity. But what is ageing exactly? And can we protect ourselves against it?

Edward_S._Curtis_Collection_People_086

Although we can see and experience getting old as a process of ‘slowing down’, becoming forgetful, and the accumulation of skin wrinkles and grey hair, it takes study at the cellular level to appreciate what is actually happening. Studying the internal workings of cells reveals unimaginable complexity and the inevitability of the ageing process. We will be hard pushed to come up with any elixir for longevity.

‘Longevity’ simply means a long life. The longest life on record is that of a French woman Jeanne-Louise Calment (1875-1997) who lived to nearly 123 years old. The biological world describes longevity as a phenotype – a set of observable characteristics of an individual resulting from the interaction of their genes with the environment. You might ask, then, how is the interaction between genes and environment affecting our longevity and causing us to age?

Our genes are strung together on chromosomes inside each of our body’s cells. Humans have 46 chromosomes in each cell. During growth and renewal, certain cells divide to produce new cells. A lifetime average is 10 million cell divisions every second. The genetic code perpetuates by processes of chromosome replication, followed by orderly separation of the duplicates in the creation of a new cell. We tend to think that each cell division faithfully reproduces and passes on the genetic blueprint, but this is far from true.

Aneuploidy

Take aneuploidy, for example. Chromosome separation sometimes goes wrong during cell division. The result of this is that some new cells may have more than or less than 46 chromosomes. Cells can usually limp along in these cases, but they have lost their vitality – in other words, they show signs of ageing.

Mutations

Mutations are probably the genetic errors with which we are most familiar. Simply put, they are random changes occurring in the genetic code within a chromosome affecting a single gene or a larger piece of the chromosome.

Telomere shortening

Telomeres
Image of chromosome, with telomeres indicated pink

Another mechanism involved in cellular ageing is telomere shortening. Telomeres are specialised pieces of DNA that cap the ends of all chromosomes. Without a telomere, the integrity of a chromosome is severely threatened. This may result in the chromosome ends forming loops by joining together, and serious difficulty in replicating at all. Critically, each time a cell divides, the chromosomes naturally lose a fragment of telomere – they progressively shorten until they eventually reach the end of the line.

Epigenetics

Epigenetics is a fascinating topic involving the study of gene expression. Certain structures within a cell are able to ‘switch’ genes on and off. Epigenetic mechanisms are what makes different body tissues do their specialised jobs – all our body cells contain the same genes, but only some are turned on.  In a chromosome, proteins known as histones form packaging material that helps to condense over 2 metres of DNA to fit into the nucleus of each of our cells. Subtle changes in these histones can interfere with their control of gene expression.

The effects of all this interference with the expression of the genetic code in our cells accumulate over time. The structure and function of the molecules that maintain the cell deteriorate with ageing, leading to a decline in the function of the cell. As the number of declining cells increases, so our bodies age more. This fits Edward Masoro’s classic definition of ageing as deterioration with advancing age, which increases vulnerability to biological challenges and hinders an individual’s ability to survive. This interpretation of ageing is also known as senescence.

Returning to the night-shift workers, the point is made that sleep is essential for enabling our body systems to replenish themselves. Upsetting normal wake-sleep patterns seems to trigger harmful processes – perhaps we do not handle sugar, stress, or appetite quite so well, for example. Toxins might not be cleared up quite as efficiently as normal.

Whether or not we work shifts, our bodies are continually mopping up harmful chemicals and dealing with the effects of bombardment by solar and other background radiation. Harmful chemicals can be external pollutants or by-products of metabolism. The more we can do to maintain our bodies in a healthy state, the better equipped we are to fend off these threats.  In the long run, though, it seems we have little defence against advancing senescence.

I gleaned much of this information through studying a free MOOC in Futurelearn: ‘Why do we age? The molecular mechanisms of ageing’  A very steep learning curve, but well worth the effort!

Do anti-ageing diets really work?

Three years ago this month, Dr Michael Mosley demonstrated ‘the power of intermittent fasting’ on the BBC programme Horizon.  He based his argument for this regime on evidence that had been mounting for some time that calorie restriction can prolong life.

However, many scientists challenge these assumptions, partly because of a lack of consistency between the various studies on monkeys, mice, rats, and even fruit flies. A review published in 2014 recognised that calorie restriction diets might be inadvertently correcting pre-existing imbalances in nutritional intake in the laboratory animals.

A team of researcher in Sydney took a different approach. They already knew that individuals who were deficient in certain growth factors did not suffer from cancer or diabetes, both of which are associated with the ageing process. They also knew that production of these cellular growth factors required particular amino acids. As amino acids are the building blocks of protein, it made sense to explore the effects of differing amounts of protein in the human diet. They analysed the proportion of protein in people’s diets, drawing on an existing national USA dataset. They also had access to health and mortality information about the people in their sample.

The Sydney team discovered something quite remarkable. Among the age group 50-65, high animal (not plant) protein intake was associated with shorter lives. This high protein group were almost four times more likely to die from cancer, when compared with the low protein group.

For those aged 66 plus, however, the tables turned. For this older group, longevity was associated with high protein intake. Those with a high protein intake were far less likely to develop cancer than those on low protein diets.

These are early days yet, and it is likely to be some time before any clear dietary recommendations can emerge. Much of the current advice for slowing the ageing process is based on having a good intake of antioxidants, dietary fibre and omega-3 fatty acids.

Antioxidants are purported to help moderate DNA damage – genetic mutations and chromosome damage – which can build over time and gradually disable more and more cells. Dietary fibre helps to moderate things such as the sugar and fats in our blood, as well as helping to maintain a healthy bowel. Omega-3 fatty acids are ‘good’ fats, for which many unproved claims are made, and even the case for promoting heart health is debated.

Does improving health through diet increase longevity? Having healthy heart and bowels may not protect us from the inevitable march of cumulative DNA and chromosome damage. Even the link between free radicals and antioxidants may not lengthen life.

It seems we have a long way to go before we can stop ageing in its tracks, but I suspect that many of us would opt for a moderately long and healthy life rather than simply a very long life.

In praise of Brassica oleracea

 

Cauliflower
Cauliflower

There can be few edible plant species that are quite as impressive as Brassica oleracea. It is difficult to appreciate that Brussels sprouts, cabbage, kale, cauliflower, brocolli and kohl rabi all belong to this single species. I sometimes liken it to the domestic dog, in all its glorious breeds and varieties, originating from the wolf, Canis lupus.

Brussels sprouts
Brussels sprouts

Brassica oleracea vegetables are a good source of Vitamin C, although the levels of this vitamin are heavily dependent on growing and storage conditions as well as the preparation method. Brocolli and sprouts retain their Vitamin C much better than kale during storage, an indication that growing your own kale and picking and eating on the same day are well worth it. Vitamin C is commonly accepted to possess therapeutic properties protecting against cardiovascular disease, cancer, supporting the production of collagen (e.g. in skin and bones), and promoting iron absorption.

Cabbage
Cabbage

In addition to Vitamin C, Brassica oleracea is also a good source of Vitamin E and carotenoids (the most well-known carotenoid is beta-carotene, the chemical that gives carrots their characteristic orange colour and gives us Vitamin A). All these vitamins act as antioxidants in the body, mopping up toxic compounds known as free radicals, and protecting against malignancy.

While the evidence in support of vitamin supplements is weak, the health-promoting effects of eating vegetables such as brassicas are gaining ground. Moreover, scientists are beginning to suggest that the unique chemical make-up of brassicas can boost health in ways other vegetables cannot achieve. Brassicas happen to be very well endowed with phytochemicals, which are substances derived from plants, that support human health. Phytochemicals include vitamins and a range of other substances that have active biological effects on our bodies.

Kohlrabi
Kohlrabi

One of the key health-promoting components of Brassica oleracea are glucosinolates, which are phytochemicals unique to brassica vegetables.  As with Vitamin C, glucosinolates can be lost or damaged during cooking by mechanisms such as breakdown by plant cell enzymes, heat degradation, and leaching into the cooking water. A recent investigation of cooking methods found that steaming, microwaving at high power and stir-frying helped to reduce the amount of these valuable compounds lost in cooking, in comparison to boiling or fermentation.

Stir-frying brocolli
Stir-frying brocolli

Purple sprouting brocolli Credit : Nigel Cattlin / Photo Researchers / Universal Images Group
Purple sprouting brocolli

Glucosinolates have a role in promoting the health of the liver and in protecting against cancer. Plant breeders and food scientists are beginning to work together to find ways of improving glucosinolate content, durability and better ways of processing our vegetables to further enhance their health-promoting potential.

If you are keen to grow your own, it’s a good idea to check your soil acidity first. You can obtain very inexpensive kits online or from your local garden centre. Brassica oleracea is susceptable to a fungal disease known as club root in acid soils. So, if your pH turns out to be less than 7, you should consider adding lime to the soil. The best time to do this is when you dig the soil over in the winter. Growing your own is highly rewarding, and the plants can look quite magnificent.

Kale growing Credit : Food and Drink Photos / Universal Images Group
Kale

Photo credits Universal Images Group: Brocollli and Kohlrabi – Nigel Cattlin;  Brussel sprouts – Michael P. Gadomski; Cabbage and cauliflower – Dorling Kindersley; Kale – Food and Drink Photos; brocolli stir-fry David Munns / Science Photo Library

Related articles

Forget the antioxidant pills https://theconversation.com/forget-the-antioxidant-pills-just-stick-with-veggies-45409

Brilliant brassica http://blog.tgac.ac.uk/brilliant-brassica/

Living with hand eczema

Have you ever experienced extreme itching and burning on your fingers and hands? If your skin erupts in clusters of tiny blisters filled with clear fluid, it’s possible you have a type of eczema called pompholyx. This is something I have personally been dealing with and trying to make sense of for the last two and a half years, and it seems a fitting subject for my first blog entry on the topic of health and science.

http://upload.wikimedia.org/wikipedia/commons/0/00/Finger_Pompholyx_1.tif
Finger Pompholyx 1

About 10 percent of people experience hand eczema, and it has a considerable impact on quality of life. It can be caused by contact with irritant chemicals or allergic reactions to non-irritant substances, and it is often claimed that emotional stress or a history of childhood eczema are key factors. Heat, cold, and sweating are also common triggers. Its impact on quality of life can be due to the centrality of our hands for every aspect of daily living and the extreme inconvenience of available measures to minimise exposure to hazards and to protect sore and itchy skin on fingers and hands. Itching is the number one source of distress, and itching on hands can be particularly harrowing.

The physiology of itching is still poorly understood. It is likely that certain chemical (e.g. insect bite) or physical (e.g. wool fibres) stimuli activate itch receptors that cause the brain to interpret the sensation as an itch. One of my personal theories is that the pressure of tense pinpoint pompholyx blisters onto the itch receptors also aggravates the itch. The inevitable scratching makes the skin sore and over-sensitive. Use of steroid creams and ointments leaves skin very dry and even more sensitive. Once the blistering has exhausted itself, the skin often starts to peel off. In my case, this occurred in the areas where the blisters had previously appeared.

Flakyhand
Peeling fingers and palm

At the peeling stage, loss of the tough epidermal layer that normally protects hands from wear and tear leaves the skin particularly fragile and vulnerable. When this first happened to me, I became acutely aware of how I used to take the skin on my palms for granted. Without this layer, I was unable to handle paper without causing my fingertips to bleed from the friction, and all sensations (heat, cold, touch) were magnified and distorted.

The epidermis also forms a barrier against micro-organisms. The bacterium Staphylococcus aureus commonly colonises the skin of people with eczema. This bacterial colonisation aggravates eczema. I have had some protracted episodes of skin flaking and erosion as a result. As you can infer from the close-up of my thumb, this state makes normal life impossible. Even the cotton gloves I have come to rely on would get caught up in the rough (and surprisingly sharp) edges of peeling skin.

Photo of infected and flaky thumb
Infected and flaky thumb

It is important to seek medical advice in case of infection. Extreme cases result in skin breakdown to the extent that the skin becomes ‘raw’ and tissue fluid weeps out. Cotton gloves are frequently recommended for protecting hands when carrying out any tasks that involve coming into contact with irritants. As many of these situations involve getting hands wet, thin vinyl (or PVC) gloves over the top of cotton gloves can provide a waterproof layer. These PVC gloves are not very strong when doing heavy cleaning or gardening jobs, and it is possible to get hold of thick PVC gloves if you have allergies to rubber or latex. I often wear these over the top of cotton + thin PVC gloves, as it makes it easier to slide the thicker gloves on.

Finding a soothing emollient cream or ointment and applying frequently is also important. It can be easy to just soldier on and hope the problem will go away, but if it doesn’t, make sure you get medical help. Probably one of the most useful things to consider with persistent hand eczema is to get some patch testing done. Patch testing involves applying a range of known contact allergens to the skin on the back for 48 hours, and then observing for signs of inflammation. In the UK, you will need a referral to a specialist clinic by your GP.

Here are a few online sources of useful information: http://www.patient.co.uk/doctor/Eczema-on-Hands-and-Feet.htm http://www.patient.co.uk/doctor/pompholyx-pro http://www.eczema.org/

Severe hand eczema: Major new clinical trial compares treatments “head to head”. http://www.bbc.co.uk/programmes/p03tqv2c