In the last article we started to discuss Dr. Jason Fung's second installment of his Aetiology of Obesity series, and I will pick up where we left off, and if you haven't read my Part 1 of my own discussion of this, well this is Part 2 so you might want to go back and read the first part before proceeding.
So we left off talking about how insulin resistance causes insulin resistance, and how insulin resistance also causes more insulin secretion, resulting in a vicious circle. A lot of people wonder what comes first though, high insulin or insulin secretion?
So Dr. Fung shows us some data that demonstrates that it's the high insulin secretion that comes first, and this should not be surprising, given what we know about insulin secretion, and given that while some other things can influence insulin resistance, nothing does it anywhere near as much as high insulin does.
It actually takes quite a while for higher insulin levels to cause significant insulin resistance, although it takes far less time for it to cause obesity, so we initially see people just obese with higher insulin levels, and the higher insulin levels clearly are a major cause of obesity, and then we see insulin resistance later, and this road finally leads to glucose intolerance.
So the interesting thing here, tying this in with what was discussed in part 1 of his lecture series, given one's set point, which has been shown to be set by hormones such as insulin, especially insulin, attempts to lose weight by caloric restriction, or by increasing activity, without reducing the insulin levels are going to fail, as this hormone will both try to get people to eat more and will downregulate metabolism to prevent the desired weight loss.
So now we're starting to get a clearer picture of not only what happens when we try these weight loss techniques, but why, and it's a hormonal disorder really, but not one we're focused on very much, and the hormonal disorder will do everything it can to prevent you from losing weight, and does so very effectively as well.
So that leaves us to look to correct the hormonal disorder, and there are several things that get out of whack besides insulin, leptin resistance for example is a big one, and this is common among overweight people, as too much fat ends up secreting too much leptin, and we become resistant to it like we become resistant to insulin when we have too much of that flowing through us.
So insulin inhibits fat burning and this is actually one of the major mechanisms that it makes and keeps us fat when in excess, a certain degree of this is healthy but if you inhibit fat burning too much and you are fat well you will tend to stay fat or get even fatter.
One of the big ways that high insulin causes more insulin resistance is when levels are persistently higher. Normally, insulin levels peak for a short term after meals, and then return to normal. Dr. Fung doesn't mention another big problem with this which is insulin resistance of the alpha cells and liver, as well as elevated levels of other hormones such as cortisol, adrenaline, and growth hormone, and all of this drives liver glucose and that tends to keep insulin levels higher all of the time, and this extra glucose tends to be secreted around the clock.
A lot of this does have high insulin levels behind it as well though, and in fact without high insulin levels causing this particular kind of insulin resistance, even though other hormones may cause our livers to secrete more glucose, it's impact is far less than what is caused by insulin resistance, and this extra glucose really just piles on.
Dr. Fung rightly points out that our eating more often does increase the area under the curve for insulin levels, meaning that the more often you eat, the more amount of times that you have to go through this post meal insulin roller coaster, so our eating more often is contributing to that problem. This is even independent of the fact that we are eating more carbs than we used to, we are eating them more often as well, and both are a problem as far as elevating insulin levels.
They even tell diabetics to eat more often, 3 meals a day plus a couple of snacks at least, and this not only increases our carb intake, it keeps our insulin levels persistently higher, in other words it increases the amount of insulin we have running through us on average, in addition to providing less periods of rest between meals when insulin is supposed to return to baseline.
3 meals a day without snacks may even be too much, and if you remember the article I did about normal blood sugar, they tested diabetics with and without breakfast, and they found that with the diabetics that skipped breakfast, their average blood sugar was 7.42 with breakfast, and 7.06 without, which is a significant amount, and there are even people who think skipping breakfast will mess up your blood sugar, but this isn't the case at all.
One of the things that happens when you extend your fast this way is that average insulin levels are lower, and that's what we want here, aside from the fact that you tend to consume less carbs, which is also a benefit. When you think of the standard diabetic diet, which is high in carbs anyway, and when they tell you to eat a couple of snacks worth an extra 30-60 grams of carbs, and what this sort of thing does to our insulin, you can see that this advice is even worse than it may appear.
I will pick this up in the next section, part 3 or this article.