Insulin, Glucose, Grim Reaper and Sweet Sixteen gene

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Sugar (wiki)

Important new reasearch published just recently by Cynthia Kenyon, University of California, described in the following Oct-26,2010 Daily Mail article (Jerome Burne):

Can cutting carbohydrates from your diet make you live longer?

Quotes:

She made her remarkable breakthrough after studying roundworms, specifically the C.elegans, a worm just a millimetre in size that lives in soil in temperate climates all over the world. By tweaking some of their genes she has been able to help these worms live up to six times longer than normal. 'Not only that, but we also know how to make them stay healthy all that time as well,' she told an audience at the Wellcome Collection in London earlier this month.
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Scientists already knew how to make laboratory animals live longer and healthier lives - you just cut back their calories to about three-quarters of their normal amount.  ... But what Professor Kenyon found out was why ­drastically reducing calories has such a remarkable effect. She discovered that it changed the way two crucial genes behaved. It turned down the gene that controls insulin, which in turn switched on another gene, which acted like an elixir of life.  'We jokingly called the first gene the Grim Reaper because when it’s switched on, the lifespan is fairly short,' she explains.  The ­second 'elixir' gene seems to bring all the anti-ageing benefits - its proper name is DAF 16, but it was quickly nicknamed 'Sweet Sixteen' because it turned the worms into teenagers.
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Discovering the Grim Reaper gene has prompted the professor to ­dramatically alter her own diet, ­cutting right back on carbohydrates. That’s because carbs make your body produce more insulin (to mop up the extra blood sugar carbs ­produce); and more insulin means a more active Grim Reaper.  So the vital second gene, the 'elixir' one, won't get turned on.

To test this, last year she added a tiny amount of ­sugary glucose to the normal diet of some of her worms that had had their genes engineered so they were living much longer, healthier lives.  'The effect was remarkable,' she says. 'The sugary glucose blocked the ''youthful'' genes and they lost most of the health gains.'
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Following Kenyon’s lead, other researchers started looking for the Grim Reaper/ Sweet Sixteen combination in other animals — and of course in humans.

They found it.

One clue came from a small remote community of dwarves living in northern Ecuador who are cancer-free. They are missing the part of the Grim Reaper gene that controls a hormone called insulin-like growth factor. The downside is they only grow to 4ft tall because the hormone is needed for growth.  But this missing bit of the Grim Reaper gene also means they don’t develop cancer and are less likely to suffer from heart disease or obesity.

Professor Jeff Holly, who specialises in insulin-like growth factor, confirms that it is linked to cancer of the prostate, breast and colon.  In fact raised insulin levels, triggered by high carbohydrate ­consumption, could be what ­connects many of our big killers. Research is at its early stage, but raised insulin triggers an increase in cholesterol production in the liver, makes the walls of blood vessels ­contract so blood pressure goes up and stimulates the release of fats called triglycerides (linked to heart disease).
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'Carbo­hydrates, and especially refined ones like sugar, make you produce lots of extra insulin. I’ve been keeping my intake really low ever since I discovered this. I've cut out all starch such as potatoes, noodles, rice, bread and pasta. Instead I have salads, but no sweet dressing, lots of olive oil and nuts, tons of green vegetables along with cheese, chicken and eggs. I'll have a hamburger without a bun and fish without batter or chips. I eat some fruit every day, but not too much and almost no processed food. I stay away from sweets, except 80 per cent chocolate.'

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Refs (older, not this one):

http://kenyonlab.ucsf.edu/html/history.html

http://kenyonlab.ucsf.edu/Kenyon_et_al_Nature.pdf




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