I read this today, British breast cancer rates ‘four times higher than eastern Africa’, and was surprised that there was no mention of possible Vitamin D deficiency. That could be a major difference between women in the UK and women in East Africa. It is worth following up on the work of Dr Cedric Garland at the University of California San Diego. He has spent about 30 years working on the different rates of colon and breast cancer in the US where the incidence is low in the south and high in the north-east. He thinks that it is due to vitamin D deficiency, and adequate vitamin D could cut rates for these cancers by a half or more. Start with http://www.grassrootshealth.net/documentation-scientistscall.
Quasi-namesake
Many years (decades) ago in the pre-internet age when I used to go into book shops, on one visit to Blackwell’s science department in Oxford I suddenly saw a book by ‘me’ on cell biology; that was quasi-namesake-me. Because of this blog another quasi-namesake has contacted me, who has some of my interests in programming and music, though with a generational shift I guess of about -1.5 to -1.9. He has a well written blog: http://robertdyson.com/
The Robert who wrote on cell biology is www.gatewaywomensclinic.com/staff-dyson.php and has now delivered nearly 10,000 babies. Oddly there was a point when I thought I might switch to medicine and do obstetrics.
I wonder if names influence people. If we were to take cohorts of quasi-namesakes would we find unexpected correlations? I know that my given name is a real namesake and was chosen by my mother because in the 1930s she saw movies with the actor Robert Taylor and found him attractive.
Vitamin D and sunlight
The other ‘food’ topic I have been interested in for some time is vitamin D. There will be more comment to come on this, but recently because of the discussion about Muslim women in Europe wearing the burka I was wondering why vitamin D deficiency had not been mentioned as a problem. A major route to getting enough vitamin D is through synthesis in our skin from exposure to UVB.
Vitamin D plays such a central role in cell processes that deficiency causes many health problems. In the days when rickets was a problem for children, it was not rickets that killed them but infectious diseases for which they had little immune resistance. I can accept that in places in the middle east where the sunlight comes strong through a clear sky and women have a back yard where they may wear less body covering there may be less vitamin D deficiency, but in Europe where sunlight is weaker and skies are cloudier and in winter UVB is near zero anyway, vitamin D deficiency will be a real problem – especially for women coming from the hot countries whose skin has pigmentation for UV protection as well. A the very least these women should be taking oral vitamin D supplements regardless of the argument over the burka.
[Postscript: I should have used Google before these notes. I find there is some recent discussion in Letters in The Independent on 20/07/2010. It shows that one assumption of mine is wrong. One letter says, “The American Journal of Clinical Nutrition for June 2007 reported that, out of 178 burka-wearing women studied by the United Arab Emirates University, Al Ain, only two were not vitamin D-deficient.” I did not find the word “burka” in the paper and some did expose their face and hands, but given that the exposure to sunlight was 1 minute per day (+-3.8) {I did not find what -2.8 minutes exposure meant!} they are secluded from the outer world. Vitamin D oral supplement was recommended.]
Newton’s law of cooling
I have been making yogurt since 1965. After initial trial with a yogurt making kit the method became simplified into equal quantities of evaporated milk and boiling water poured into jars that then have a spoonful of the last batch of yogurt added. These jars then go into a polystyrene milk-bottle keep-cool container that I got in 1962 as an offer with Kellogg’s cornflakes! Left overnight there is perfect yogurt in the morning. There is some pleasure in still using this battered polystyrene box, up-cycling it in current jargon, for almost 50 years – technology you can trust.
The past few years I have had some mild allergy to “standard” milk that I don’t have with organic milk. Now I am making yogurt with organic milk that needs heating to 82C to kill bacteria and prepare the milk protein to help setting, and then cooling to 43C before adding some of the last batch of yogurt.
The cooling takes over an hour and to start with I kept going to check because the final temperature is critical. Then I thought that I would make use of Newton’s rule-of-thumb about bodies cooling in still air. It was a delight to see the near linear plot of log(temperature difference) against time. This I now use by taking the starting temperature and one other reading at a later time that an excel spreadsheet then turns the time I need to go and add the yogurt – ping.
The temperatures are measured with an IR thermometer that I got to help with research on house insulation. The measurements of temperature and time are rough – same eyes reading both and jotting down – but fit for purpose.
Final points: The top and bottom temperatures of the jar are different and half-way up the jar gives a reasonable average. The milk in the jar is hotter than the temperature on the outside, in my case by about 2C. I add one dessert-spoon of yogurt and that cools the milk by about 1.5C . The final milk temperature I aim for is 43C, so 43C on the outside is just about right.
At last into that courtesy-of-Kellogg’s 1962 insulating box.
Probably all this is over done, but it is irresistable to let a bit of our skills affect everything we do.
Inspiration that humbles
This is the most inspiring talk I have heard for ages: Anil Gupta: India’s hidden hotbeds of invention.
The TED summary just hints at what is being done: “Anil Gupta is on the hunt for the developing world’s unsung inventors — indigenous entrepreneurs whose ingenuity, hidden by poverty, could change many people’s lives. He shows how the Honey Bee Network helps them build the connections they need — and gain the recognition they deserve.”
One valuable comment Anil makes is that we often discard solutions to a problem because “they do not scale”. He reminds us that if people in a locality find a solution for an issue that works only in their area – that is enough for them. Probably we are better off with a million local solutions than one global solution. This is like Darwinian evolution; let’s develop what fits in each niche.
70 hectares of Geo-engineering
Can painting a mountain restore a glacier?. Although even if this painting a mountain white will have only a small local effect, it is an inspiration. There are a lot of us (part of the problem) so if we all undertook something similar in scale the impact on climate would be great.
Forty years on
The Limits to Growth report is nearly 40 years old. I read it when it was published and was dismayed that it seemed to gather more negative than positive assessment. At last there is a government response to it: Government review to examine threat of world resources shortage.
RealClimate has an excellent discussion on “How do we know what caused climate to change?”: On attribution is by Gavin Schmidt whom I find the sanest exponent of global warming issues. For the mathematically inclined there is a link to a beautiful discussion of stochastic versus deterministic trends: Not a Random Walk. It is worth comparing these with the petty put-downs being thrown at Gavin: Real Climate’s Gavin Schmidt: A Foot in His Global Warming Mouth by John O’Sullivan, guest post at Climate Realists. Real scientific discussion requires a lot of detail. Sometimes for general interest one has to miss some of the irrelevant details. The complaint is that in a discussion, Learning from a simple model, Gavin mentioned a factor two in an equation because the atmosphere radiates up as well as down, when really any volume of the atmosphere radiates in all directions. So Gavin was not strictly correct. However, if you do the math properly the factor in the equation is indeed two – the sideways radiations are not relevant, what matters is what eventually goes straight up and straight down (I had better say at the point on the earth that you are considering else someone will say that up & down depends where you are). Why did John O’Sullivan not do the math to show that Gavin was wrong in essence? – because Gavin was not wrong.
From code to code
The start of digital computing as we know it came from Alan Turing’s work for code cracking during WW2. There have been other big developments from the push to simulate nuclear weapons and forecast weather & climate to the mass use of small personal computers for playing graphic games. Code again seems to be a driving force in development: The number crunchers who are saving lives. I remember this chemistry by computer starting in the 1980s and this is an amazing development in scale since then. Probably this will be a mutually beneficial development in more that the obvious way; maybe we can eventually genetically engineer a computer to grow from biological parts.
Food, nutrition and diet
On a whim, last year, I started to look into what is known about insulin. I mentioned this to my GP one day who then said, “You are not diabetic are you?”. He persuaded me to have an A1C that after some delay, as a typical always-ignore-medical-problems male, I booked myself in for. I was within the bounds but at the higher end for blood glucose level. This turned the insulin search into one biased towards practical understanding of the effects of food on insulin and fat. The starting point was a UCSD-TV lecture by Robert Lustig on childhood obesity that you can find on www.ucsd.tv (with other fascinating lectures). I have forgotten how I came across that early but it was a great inspiration. I was stunned by the discussion of glucose & fructose metabolism.
I had a wonderful teacher of chemistry at school, Bill Waterhouse, who spent extra hours with me to give me a good start with organic chemistry and later he told me he thought that I should have done a degree in biochemistry, but that was not the route I took. [I mention my teachers from decades ago in part to remember them but also to flag the importance of this profession for our human future.] Over the years I have picked up some biochemistry and physiology partly from interest and partly to help in projects I have been involved with but I always accepted the experts without any delving into details. So I thought fructose was good and fats bad because that was what the government scientists advised.
I saw a lecture by Michael Pollan on uctv.tv and was thereby introduced to his writings. He was discussing his book, In Defence of Food. He gave a summary of its important conclusion: “Eat food. Not too much. Mostly plants.” and commented that with that you did not really need to read the book. Of course reading the book then becomes irresistible. There is a rich diet in its 208 small pages.
The most important insight for me was that the recent rise of the industrially produced diet of heavily processed ingredients has a big danger. We have evolved over hundreds of thousands of years to choose the mix and quantity of the food we eat. There was a big change already in going from hunter-gatherer to pastoral agriculture that Pollan suggests we have not yet fully adapted too, but we will leave that aside. Of the foods that were available up to about 1900 we knew if they were good or bad for us without consulting a nutritionist, otherwise humanity would have ceased to exist. 100 years on and we can manufacture food for which we can no longer tell that. It may smell and look and taste like good food, but it could have no real food value for us, it could be harmful. Some is harmful, not with deliberate intent of the manufacturers because at the very least they don’t want to kill their revenue source, as it leads to obesity and its consequences such as diabetes and cancer and joint problems. Sugar especially was just a small part of some produce, now the world is awash with sugar in almost every processed food; with its enhancement – high fructose corn syrup. We do not have a gut way to decide on these foods, they seem fine by our evolved criteria but our built-in instruments are deceived.
We are focussed on acute disease that kills or disables fast, less so on chronic disease that takes decades to develop. This is not to say that there can be no input from scientific study but we need to be sure that it really does improve our food.
Interpretation with many variables
This is an excellent example of the difficulty of interpreting historical data. Tree rings: Chainsaws at dawn. Tree ring widths are determined by several factors, including temperature and rainfall. We need other information if we are to deduce temperature from tree ring width. In practice this seems to be choosing only trees in areas, “You can extract climate information from trees – mostly pines – from more extreme environments, like northern Scandinavia and Siberia; trees from high altitudes and high latitudes where the summer warmth was very important.” There is no escape from complex modelling.