We need to talk about sugar. Remember ‘a calorie is not a calorie’* and my homage ‘a carb is not a carb?’. Well, it turns out that ‘a sugar is not a sugar’.
(*This is Lustig’s nutritional play on the thermodynamic principle that ‘a calorie is a calorie’ as measured in the laboratory and pedalled for decades by the food/sugar industry. Lustig is a world renowned paediatric endocrinologist and food campaigner. Read his book ‘Fat Chance: the bitter truth about sugar’ if you prefer Campagnolo Super Record to the Veloce ramblings of a half-starved cyclist.)
To recap blog 2 on carbohydrate, your body’s a temple and it runs on the sugar glucose (stored as glycogen). If you take a defined amount of glucose on an empty stomach your temple responds quickly with a predictable amount of insulin to instruct muscles and organs to take it in to burn (instead of protein and fat) and to store as glycogen for that next training session. By a mathematical sleight of hand, the predictable insulin peak caused by glucose is converted to 100 to make the sums easier and called GI for Glycaemic Index. (The sums for time and angles are not so easy as they’re based on Babylonian base 60). Again referring back to blog 2 on carbs, the GI values for cooked white and brown rice are 80 and 50 respectively; the white/brown GI differences for bread and pasta are not as great because they’re made of flour which is by definition the grains ground up.
Now to the villain of the piece: fructose. This has a GI of 20 which sounds great, doesn’t it? But lard (yes, I mean lard) has a GI of, wait for it, 000.00/zero/zilch/nowt; but does that make lard healthy?
Let’s do a thought experiment
(Advisory: requires the capacity for abstract thinking so some of you may have to skip this section.)
Imagine you live in an old church/mosque/synagogue/gurdwara/pagoda rather than an ordinary house. Because of this, you could say that ‘your abode’s a temple’ (geddit?). As a treat, you really like jelly beans when relaxing in your temple. (Advisory: don’t try this at home as they contain dangerous levels of fructose stuck together with sh1te.) Jelly beans in your town only come in packets of 10 and in green, your favourite, or red, which you detest. So you get back to your temple and open a packet of green jelly beans, eat 9 giving yourself a lovely warm, energised feeling and put the 10th in a special cupboard for next time. But half the time the shop gives you the wrong packet of 10 red jelly beans; you eat 2 in desperation and scatter the rest randomly around the temple as they’re really no use to you. Because eating 2 measly red jelly beans doesn’t give you that warm, energised feeling that 9 green ones do, you’re often driven to opening several bags, one after the other, in the hope of finding green jelly beans. Over time the temple gets totally bunged up with sticky mess from discarded red jelly beans. The walls and windows bulge, the furniture is ruined. Family, friends and neighbours notice. Eventually even the plumbing, heating and electrical systems are damaged.
You’ve probably figured out by now that green jelly beans are glucose, and the red ones fructose. In real life, most ‘sugar’ in food is sucrose (glucose-fructose) or sort of like double-size, orange jelly beans made from squishing together a green and red one. Fructose is a sugar in chemical terms but not really as far as your temple is concerned as it can’t be burned by muscles or organs. The liver can turn a small amount of fructose into glucose, but eat too much at once and it’s made into fat instead; and ‘bad’ fats at that. It gets worse; at the same time as making you fat and sick, fructose messes with hunger control so you keep eating more even though you’re telling everyone, especially your doctor, that you only eat lettuce leaves. It gets even worse; thin, fit people on a sugary diet are still more likely to get sick on fructose in the long term (try googling ‘metabolic syndrome’ if you need a good laugh).
Here’s the bottom line. That white powder we call sugar is really crack-carbohydrate. It has many street names; pretty much anything called ‘syrup’ or ending in ‘ose’. We’ve invented all kinds of delicious and tempting ways to deliver it in solid and liquid form. Thanks to the food/sugar industry it’s everywhere, even in salty and savoury foods, and it’s out to get you.