Glucose - Should We Be Eating It ?
I say NO. But who am I to make such a statement ? What qualifies me to do so ? Let me respond to these questions, and clarify the basis of my claim.
I am a first year nutrition student, in week 5 of term 1. In other words, I am a novice, I am not an 'expert' in any sense, and yet I dare to put forward a position on glucose here, not only that, but one that goes against the mainstream of established nutrition science. How dare I ?
First let me explain the basis for my argument that glucose does not belong in the diet. This rests on the observation, from studying the digestive process, that carbohydrates and lipids are treated very differently by the body. Fats are absorbed inside the small intestine directly into the bloodstream, via the lymphatic system, without any control mechanism intervening. We eat fat, it goes straight into circulation. Glucose molecules, on the other hand, are sent to the liver, whose initial response is to do what it can to PREVENT them from entering the bloodstream, by storing them away inside its own cells. These have limited capacity however, and are soon overrun. The body anticipates this failure by signalling to the pancreas, as soon as food enters the mouth, that blood sugar is about to rise dramatically and to release insulin in time to cope with this situation. Elevated glucose is highly toxic to the body so the function of insulin is to remove it from the blood as quickly as possible by pushing it into muscle tissue and fat cells, and so return blood sugar to within its acceptable tolerance range.
Glucose serves some important functions within the body, it is the energy source for red blood cells, it is used by the brain, and by muscles for short, explosive bursts of activity. The amount required for these roles is minimal, there is around one teaspoon of sugar in the blood at any one time, and its level is tightly regulated by the liver. This organ is easily capable of topping up glucose levels as and when needed.
As a new student, this is my first encounter with such information. The summary above is a first impression, an initial understanding. As such, my task is to try and make sense of what I am finding out, to determine its significance, to grasp what is going on here. As part of that process, I am struck by the following questions -
Why does the body respond to fat and glucose in such different ways ?
What does this tell us about ourselves and what we should be eating ?
I do not come to these questions from nowhere. I have a background in crisis management, I train incident management teams. When I look at the body's reaction to the ingestion of glucose it looks all too familiar, to me it resembles an emergency response. The alarm goes off as soon as we eat, fire trucks turn out from the station to be on scene in time, the situation is brought back under control before irreversible damage is done.
It is possible to do this every day, almost every city and community has the capability to turn out trucks to fires and other incidents daily and prevent serious loss of life and property. But this does not make it a good way to live. I've observed businesses that do run this way, staggering from one crisis to another, always a day away from catastrophe, but no one considers it good practice.
From these observations I put forward a hypothesis, it is this -
The liver would prefer to retain exclusive control over glucose levels in the blood, it does not want to have to activate an emergency response whenever we eat. It is not a good idea to put the liver through this stress by eating carbohydrates.
Fats on the other hand present no problem, certainly not for the liver.
This is the basis of my claim. What exactly is its status ?
it is a hypothesis, no more, no less
it arises out of a few observations, a lot else is going on
it may well be wrong
it is the product of a first year student, 5 weeks in
I reserve my right to drop it whenever I choose
This sets my claim in its proper context, it is worth only what it is worth, and that may not be much. In its defence, however, is this argument -
My hypothesis is the BEST EXPLANATION I have come across so far for the questions that struck me as I encountered this information for the first time on how the digestive system deals with carbs and lipids. I will continue to hold on to it until I find a BETTER ONE.
This is why my status as a novice to the field does NOT disqualify me from making a claim such as this. Being a new student means that I HAVE QUESTIONS, and those questions can be as incisive, if not more so, than any an 'expert' may ask. This is because I am looking at the material with FRESH EYES, and a unique perspective, some of which I have shared above. My answer may be stupid, we'll see, but the question I ask is a valid one, and requires explanation.
Asking questions in this manner is an important part of the learning process. It is me attempting to MAKE SENSE of what I am learning, to determine its significance, and fit it into the larger picture. My hypothesis is an invitation to anyone to offer me a better explanation than the one I have come up with.
When I put my idea forward on Twitter one response I received was this, 'Did you just make this up ? Where are the studies that prove this ?' To which I replied, 'I totally just made it up.' I see no need to apologise or be defensive about that, my hypothesis is worth what it is worth, by all means take it with a pinch of salt, but it stands until I hear one that is better. Quite a few people on Twitter did tell me just to drop it, but they didn't offer me an alternative, so I won't.
There is another angle to this, the question of bias. I am approaching my nutrition studies from the perspective of a carnivore, I am prejudiced against carbs, I have a dog in this fight. This obviously raise the question of confirmation bias - am I just looking for arguments that support the idea of excluding carbohydrates from the diet ? I have an answer to these objections -
Is there a danger of confirmation bias ? YES
Am I emotionally invested in my biased viewpoint ? YES
Am I aware of the danger ? YES
Should you be aware of my bias too ? YES
At no point am I claiming to be neutral, or 'objective' in ANYTHING I write on this blog, which is one long series of arguments in favour of a carnivore way of eating. I have an ETHICAL commitment to carnivore, I WANT this diet to be a healthy one, I want people to adopt it. Nevertheless, I also have an ethical commitment to TRUTH, and this takes precedence over my desires and emotions. That means if I have to drop this hypothesis, or any other, because it turns out to be wrong, then I WILL.
I think its better to be up front about this, my bias, my ethical standpoint, my emotional investment, rather than put on a pretence of 'objectivity'. On Twitter, several responders did accuse me of confirmation bias, and I can see why they did so, its a fair accusation. On the other hand, I still don't have a better explanation than the one I have put forward for the questions I want answered, so, bias or no bias, the hypothesis stands, at least for now.
That's an invitation, people, prove me wrong, see if you can out do a first year student :-)