Archive for September, 2009

Pie in the sky ..

September 8, 2009

Appearing recently in the media have been submissions from scientists tabling possible worse case scenarios and last resort tactics to avert catastrophic global warming.

Some of the propositions involve deflecting solar radiation by placing mirrors or reflective dust in the upper atmosphere with the intent of deflecting solar radiation and thus with the hope of countering rising temperatures. Are they kidding?

As with other 21st century problems we need to address climate change with an appreciation of causality and addressing that at the root rather than treating symptoms by dispensing some additionally constructed human remedy. There is scope for greater insight into this as may apply to climate change as there may be from delving into the same basic flaw in the way mainstream human health-care is delivered.

Climate change and sustainability are complicated issues with diverse and often in-congruent arguments from various camps. However, I can simplify matters somewhat..

Try drawing two circles on a piece of paper to loosely represent Sun and Earth. What does the one give the other? It is child’s play, isn’t it? The Earth is reliant upon the Sun for energy, right? Rub out our circle that represented the Sun and what are the implications?

The Earth is an energy system subservient to the Sun. Life upon Earth in all its’ diversity is/are energy (and nutrient) systems subservient to the whole Earth. Humans are entirely subservient to those energy and nutrient hyper-cycles that nature has constructed by the process of evolution and all made possible by the Sun.

Through Defra and one of its’ offspring FERA (Food and Environment Research Agency) the government, via Hilary Benn, the minister responsible, recently launched a consultation document upon future food security and entitled, I think, ‘Food Matters, part 2′. This is a document that questions the future of food security on a number of lines.
Concerns are expressed about rising global populations, increasing wealth in developing nations and anticipated change in dietary expectations of wealthier people, further concerns are declining fertility, dependency upon finite fossil fuel reserves for agrochem’ production, falling water tables, and potential changes to weather patterns, temperatures and precipitation. In short it is concern about energy and nutrients and whether we are fast reaching the limit of the total capacity of the Earth to feed a rising population. The problem lies rooted in conventional agricultural methods as applied by western civilisations because inherent in the practice at a number of levels is the principle of deferred accountability. Conventional agriculture practices with complete deference to natural energy and nutrient hyper-cycles. 21st century challenges are the consequences of carrying on without any regard for these natural constraints. One such constraint, somewhat fundamental, was illustrated by drawing our two circles.

Food is produced by capturing solar radiation and nutrients through the life giving process of photosynthesis. So if we register already concern over ability to meet demand then one might deduce that we need to capitalise upon all the solar radiation we can capture, and in the face of passing peak oil we acknowledge we may have to produce increasing amounts of energy for our domestic and industrial needs from renewable sources. The primary capitals here are Sun, Moon (tidal) geothermal, and morphological (fission/fusion). Factor in that energy production may have to be carbon neutral or even carbon negative (and soon) and photosynthesis looks increasingly attractive to produce energy for requirements other than simply and primarily for food.
Such a strategy would place a huge burden upon the suitable agricultural regions of the world. We’ll need several things to meet this burden but not least will be plenty of solar radiation. Best not to pin too much hope upon launching reflective material of any kind into space. I mean, its’ hardly rocket science..

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Artificial Sweeteners – artificial hope?

September 8, 2009

Dr John Briffa raised the issue of artificial sweeteners in his blog of 4th September 2009 headed: The myriad of reasons why artificial sweeteners may not deliver on their weight loss promise”.

Sooner than post at length on Johns blog I posted a reply with link to these paragraphs:-

John, no, I hadn’t researched xylitol any more than having seen it advocated in the aforementioned book. I agree entirely about cause for caution. The entry in Wikipedia reads as though it could have been compiled by those of largely enthusiastic persuasion.
The claim is that spoon for spoon there are 40% fewer calories than sugar but nothing is mentioned about relative sweetness. For all I know one might need to use 40% more of the stuff to satisfy ones palette. There is a link in the wiki to the BMJ; it is not available to me.

What should we regard as natural anyway? Our forebears have a long history of exposure to many sugars intrinsic to many natural food sources including glucose and fructose yet as you point out there is reason to be concerned about fructose and the associated dependency upon the liver to break it down. At 50/50 glucose/fructose common (table) sugar could be labelled natural at one level but considered entirely un-natural by virtue of refinement and context. I guess the same argument holds for the sugar-alcohols (sorbitol, xylitol etc.)
I was not especially advocating xylitol – there seems every reason to categorise it with the ‘artificial sweeteners’; and by the same token, might there be a case to argue that sucrose and perhaps even honey deserve inclusion in that same category?

If human progenitors existed for substantial periods largely as folivores and frugivores we might consider that we ought to be well adapted to these dietary components; fruit and veg in general are deemed to be good for us.
However it could be a pitfall to overlook the contrast between modern cultivars and naturally occurring sources as was. Modern varieties have resulted from the pursuit of sweetness and size. Our ancestors quite likely could not select just the ripest fruits while foraging but probably had to consume unripe or, most certainly under-ripe, fruits too;¬† fruits with a considerably higher fibre to sugar ratio than our modern equivalents. There’s another contrast too, one might expect our ancestors to have consumed fruits whole.

So 21st century folks in the main have an artificially sweet tooth(?), consume a diet unnaturally high in GL(?), consume too little (non-cereal) fibre(?), and are intolerant to the taste of foods rich in bitter tasting compounds which may be good for them – such as dark leafy greens(?).
Increased exposure to sweeteners, especially the ‘artificial’ ones, in commonplace products cannot be congruent with the likely benefits of re-educating overly ‘sweet-tooths’.

Because I acknowledge the dietary benefits of fibre and the anti-oxidant properties of limonene I do on occasions consume an orange complete with pith and peel. I expect most folks would find that unpalatable and eccentric practice, yet the declaration serves points in para. 3.

The soft drinks industry (US -‘soda’) is clearly factorial in conditioning folks to sweet-tooths and this has come to the attention of at least one US state, as was reported recently in New Scientist, who advocated increased taxation upon sodas, much like the instance of Dr David Walker who tabled a motion for debate and vote at the Glasgow conference¬† earlier this year (defeated only by a narrow margin) to increase taxation upon chocolate bars and confections on sale in the UK.

Concluding just a little politically I think there is mileage to be gained from considering the role of regulators on both sides of the Atlantic. Is there scope for improvement in the efficacy of regulation and education?