Monthly Archives: May 2010

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 (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 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.

Another of those hockey-stick trends

Man-made climate change blamed for ‘significant’ rise in ocean temperature is about the rate of rise of ocean temperature in the top 700 m, with a finding of significant rise over the 1993-2008 period of the study. A little more exegesis in A worrying set of results for marine life – and for humans.

Unlike the Bullingdon Club members who could easily pay the bill for trashing a place for fun, if we do not start soon we will be unable to pay the bill for the planet trashing we are doing and will be thrown into a hostile world. We seem to be under the spell of The Markets.