I said a lot about Diabetes yesterday and about how its affected my emotions and what i have to do.. but i haven’t explained a lot about what it is, and the details. I’m putting this behind a cut cos of the length of the posting, and because not everyone wants to read this stuff.
All diabetics have problems of varying levels with their pancreas: specifically, something called Beta Cells which are found in the pancreas. Beta Cells produce insulin. Everyone knows we need to eat to live: food that goes into our mouths is broken down by the alimentary canal to glucose, which enters our bloodstream, and from there, goes to the brain first (cos without the brain overseeing everything, there isn’t much point to the rest of it), then to the muscles, where its used to do things, like me typing on this keyboard, breathing, and so on, and then to the liver, where its stored. There is a certain storage capacity in the blood itself – your blood will never be completely empty of glucose – but the amount that is in the blood itself is normally very tightly controlled by the body to an amount between 4 and 6 mmol (millimoles per litre – its the measurement used in the UK; the US uses mg/dl). If the blood contains more than this, then some is stored in the liver as glycogen (a little more readily available form than fat), the rest is stored as fat, and we all know about THAT!
The role of insulin is complex, but on a simple level, it acts as the key that enables glucose to enter a cell. Glucose cannot normally cross the cell membrane – there are various “locks” on the cell membrane and insulin is the key that enables those locks to open and allow the glucose through. This is why the role of insulin is so crucial: without it, your blood could be pure glucose, and it would do the cells in your body no good at all; they simply would not be able to access it.. and would die.
There are three types of Diabetes. Type 1 (T1) is the one everyone knows about – and you generally know if you have this, from an early age. In this, the beta cells aren’t working at all. Period. zip. nada. no insulin produced; and with this, you have to inject insulin and carefully manage your injections and diet to be sure that you inject enough insulin to cover what you’ve eaten.
Gestational diabetes is the third type: this is often temporary, picked up during screening and caused by pregnancy hormones (although, left untreated, such women are at risk of developing T2 diabetes later in life, and the children are at risk also of T2 diabetes and childhood obesity).
The second type, and what i have, is Type 2 (T2) diabetes. This is also known as late or adult onset diabetes. The causes of T2 diabetes are very complex, although many many people believe its caused by being overweight, a lazy lard arse, who stuffs her face with sugar – particularly if you believe the media reporting over the last few years around the issue. This isn’t the case: its genetic, and obesity is actually *caused* by the same issues that lead to the diabetes (which is why so many T2s are also overweight). There is some evidence to show that the dietary advice of the last 25 years to eat a low-fat/high carb diet is partially the cause of the ‘obesity/diabetes epidemic’, and that the previous advice, to eat a diet low in carbs instead, is the better advice for those wishing to lose weight. Simply being overweight may be the trigger for diabetes to develop, but also things like stopping smoking (with the associated weight gain), stress levels, high blood pressure, high cholesterol – there’s a whole raft of problems/symptoms that come under the generic title of “Syndrome X” or Metabolic syndrome.
In those with T2 Diabetes, the “locks” on the cells that insulin unlocks to allow glucose through often start to change (the change being caused by a hormone produced by fat – which is why the NHS bangs on about reducing your weight by 10%, as this is often enough to eliminate the production of this hormone), so that the key that insulin is no longer works (insulin resistance). This causes a couple of things to happen. Firstly; glucose is no longer taken up at the same rate by the cells, so there’s more glucose floating around in the blood. This glucose, since its unneeded, gets converted by the liver to first glycogen, then when the liver stores are full, to fat. The cells start hammering the pancreas: “i need energy!” and the pancreas makes MORE insulin in order to unlock the cells. This insulin hammers home the glucose – dropping the blood glucose to below that 4 mmol – and at this point, the body starts to feel sweaty, faint, irritable… basically, having a hypoglycaemic episode. At this point the natural urge is to reach for something sugary to raise the blood level again (my favorite when this happened was a mars bar or a cadbury’s easter egg!) … and so the cycle continues – a vicious cycle, that is difficult to break.
[just to be clear: not all hypoglycaemia is due to diabetes. I myself had hypoglycaemia ever since i was a teenager and i was tested for diabetes regularly at the time (although always via my urine: I do wonder, if i was a teenager now, and my Fasting Blood Glucose was tested, what the result would've been). ]
But its worse than that. over time, with high amounts of glucose and insulin floating around, the surges up and down, the beta cells start to develop problems and die. eventually you have no beta cells left, and at this point, you have to inject insulin. (all T2s eventually have to go this route: how fast this happens is generally down to how far into the disease you get diagnosed and how good your control over your diet once you’ve been diagnosed – crucial to avoiding the death of beta cells, is avoiding those surges and keeping the blood sugar as stable as possible).
In addition, and left uncontrolled, other problems start to happen: The high amounts of sugar start to “rust” the inside of your arteries, making your blood pressure rise. Cholesterol starts to rise too – which makes the artery situation worse. Strokes, heart disease result from this. Since the blood glucose is high, the eye fluid starts to absorb glucose, which affects the shape of the lens in front of the eye. this blurrs the diabetic’s sight, and left untreated, can cause blindness. The “rusting” or “furring” of the arteries cause circulation problems, which mean that extremities such as the feet are slow to heal; leading to problems and often resulting in amputation. And of course, there’s always the risk that a nice blood clot will break free and cause a heart attack.
I think its clear that i have to gain control over my diet, to reduce the surges (or spikes) in blood glucose. In order for this to happen, i have to stop eating the things that make my blood glucose (BG) surge. These things are the obvious: sweet, sugary things, like chocolate, but also things that are easy to digest: anything made from white flour, like biscuits, bread, cakes, etc., is a no-no. Other “simple” carbohydrates such as potato, white pasta, are not a good idea, as all are very easily and readily absorbed by the body (producing that BG spike). This is the basis behind the “GI Diet” – basically, people have sat down and worked out how fast something is absorbed by the body (The Glycemix Index) and produced lists of such things. Unfortunately such lists aren’t really a good idea, for the simple reason that people don’t eat foods as they’re listed. A slice of wholewheat bread, for example, has a GI of 49 – but who eats bread alone? simply putting a bit of butter on the bread changes that GI – as the fat slows down the absorption of the carbohydrate by the body. So its difficult to make choices based on the Glycemic Index alone, and in addition, there are quite a few surprises there: jacket potatoes are surprisingly high, and peanut butter is surprisingly low!
For this reason, i’m going to be minimising the amount of carbs in my diet. In addition, Insulin Resistance – in everyone! – is often worse in the morning (and what’s the main feature of 99% of the nation’s breakfast? you got it, carbs!) so its particularly important that i avoid carbs then; and if i must eat them, to eat them with fat/protein in order to slow the absorption.
[You might be asking why i'm not cutting down on other things - like protein and fat, why i'm not panicking and thinking "I can't eat anything at all!". The reason is very simple: both protein and fat have *much* slower absorption rates, and both don't convert 100% to glucose - only 50% of protein converts to glucose, and as little as 10% of fat. For a diabetic, protein and fats are your friend. [Ah-ha, but what about cholesterol, i hear you cry? well, that's a subject for another day, another post, but, if you're interested, see here).]
What is clear to me, from talking to other T2 diabetics, is that different carbs affect different people differently. Some cannot tolerate potato in any way shape or form. Some can; i spoke to one guy who can have precisely 3 chips before spiking his BG! For some a banana is a no-no, still others are fine with bananas. a lot of it is to do with how healthy your beta cells are – in me, because i am still quite young, and my diabetes has been diagnosed before any of the major problems i listed above have occured (which is often how diabetes is discovered), i probably have more healthy beta cells than someone who is much older, with poor circulation and high blood pressure. this will allow me to correspondingly eat more carbs before spiking; what i have to do is to work to discover what those carbs are, and, more importantly, how much. And this is something i’ll likely have to keep an eye on for the rest of my life.
How do i do that, how do i find out what those carbs are, and how much i can take? well.. that’s the subject of my next post….