The How’s, When’s, Where’s and Why’s of Sugar Making You Fat PART 1

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If you are reading this then chances are you’ve already heard me bang on about how it’s the sugar in your diet and not the fat that is making you fat and stopping you from achieving your health and wellness goals.  Not only is it making you fat but it is also making you sick and unhealthy.  I continually get a lot of enquiries from my clients about what to eat in order to lose weight and when I tell them to eat more real food and eat less sugar they really struggle with this concept.

So my goal here is to show you once and for all the science that it is absolutely 100% the sugar in your diet and NOT the fat that is making you fat and sick.  Its quiet a complicated process that delves into the deepest darkest reaches of biochemistry and physiology and so in order to allow this whole process to sink in, I’m going to spread this out over three articles.  That way you are given some time to absorb and learn what exactly is going on when you eat food and in particular sugar.

By the end of the third article you will be utterly convinced of the evils of sugar and hopefully you’ll undertake the necessary steps that I’ll outline to break your addiction and eliminate sugar from your diet once and for all.

What Is Sugar and Where Do We find It?

There are three important sugars in our life, glucose, fructose and galactose.  All of the other sugars you will encounter in your diet are simply combinations of these three.  For example, milk contains lactose, which is galactose + glucose.  Beer contains maltose, which is glucose + glucose and common sugar, whether it is raw sugar, brown sugar, white sugar, icing sugar or caster sugar, they are all the same and are all often referred to as sucrose and is this is simply glucose + fructose.

As a species, we’ve been eating foods made up of proteins, carbohydrates and fats for as long as we’ve been walking around on two legs and during this time, evolution gave us a brilliant system of ensuring that we stay thin and don’t starve to death through famine or over eat in times of feasts and I’ll talk more about this system shortly.

In the early 1700’s European explorers discovered spices like coffee and cocoa and began importing these back to England and Europe.  However, being very bitter to the taste, it took some time for these food stuffs to really take off in popularity.  It wasn’t until the discovery of sugar cane that we worked out that by adding the refined substance from sugar cane to coffee and cocoa, that we were able to overcome the bitterness and eventually come to enjoy it.

So by 1815, British subjects were consuming approximately 7 kgs of sugar per person, per year.  By 1955, this figure had risen to 50 kgs per person per year.  Just as a side issue, when sugar is refined from sugar cane, 99% of the original food (mostly fibre) is removed leaving only the sugar syrup.  Likewise with flour, by the time it is milled, 90% of it (the bran) has been removed.  Sugar and flour are both reduced to the constituent parts glucose and fructose (as in the case of sugar) and glucose (as in the case with flour)

Today virtually every single food item found in a typical shopping centre NOT in the fruit, vege, meat or delicatessen has sugar in some form added, such is the addiction that we have with it.

How Do We Convert Food Into Energy?

The body’s most preferred source of energy is glucose.  Every cell in the human body can use glucose for energy and glucose can be found in almost every single source of food we humans eat except meat.

Galactose is only present in dairy products like milk and cheese.

Fructose IN NATURE is only found in small quantities in ripe fruit.  I highlight the words IN NATURE because we now consume per person almost 51 kgs of fructose per year in Australia and I can tell you now, we do not get our fructose supplies from fruit.  As an example, one apple contains approximately ½ a teaspoon of fructose.

So, our bodies need a constant supply of energy to function 24 hours a day, 7 days a week, and 365 days a year for our entire lifespan.  However, we only eat 3-5 meals per day so to ensure that we have a constant supply of energy in the form of glucose in the blood stream, our body has a simple but very effective negative feedback system to keep our blood glucose levels at optimum and it works something like this.

When we eat, our food is broken down in the digestive system and any glucose in the foods we’ve eaten enters the blood stream causing our blood glucose levels to rise.

The pancreas secretes insulin to reduce the amount of glucose in our blood stream and it does this in 3 different ways.

1. Firstly insulin provides all of the cells of our body with a means of grabbing the glucose in the blood stream, the exception being the brain which doesn’t need insulin.  We can store about 4 hours worth of energy as glucose in our blood stream.
2. Secondly another way of lowering glucose levels is done in the liver.  When insulin is detected in the blood stream the liver uses it to suck glucose out of the blood stream, convert it to long chains of glucose molecules called glycogen for storage in the liver and muscles for later use.  You can never have too much glycogen.  Its non toxic so you can’t die from having too much.
3. Thirdly, insulin also controls appetite. Once detected in the bloodstream, special receptor cells in the hypothalamus release Leptin which sends a signal to the brain giving the feeling of fullness. Literally it tells us, “I’m Full”.

As our blood glucose levels fall due to the three insulin induced responses as described above, the pancreas releases another hormone called glucagon, which instructs the liver to access the stored glycogen stores and convert them back into circulating glucose.  It also stimulates a hormone in the stomach called ghrelin which counteracts the effects of Leptin giving us the feeling of being hungry.

And in case you were wondering, a similar system exists for when we eat fat.  Fat is vitally important for all manner of processes and I’m not going to delve into them here, suffice to say stop listening to the “eat low fat” message and read on.  Stop avoiding fat and embrace it.  When we’ve eaten enough fat, the upper intestines release a hormone called cholecystokinin (CCK) which tells the hypothalamus to suppress hunger and make us feel full.

So you see we have this perfect little negative feedback loop system of insulin/glucagon to regulate our blood sugar levels (when we eat protein and carbohydrates) and CCK when we eat fat, by controlling our appetite.  It makes us hungry when we need energy and tells us we are full when we have had enough to eat.

The cells of our body can’t just help themselves to the blood sugars (glucose, galactose and fructose) whenever they feel like it or even whenever they are present in the blood stream.  They need a protein to absorb the sugar.  These proteins are called glucose transporters or GLUTS for short and while we are aware that there are 13 of them, for the purposes of this series of articles we only need to discuss the first 5 and interestingly enough they are called GLUT 1 – GLUT 5.

Protein	Transports	Stimulated By	Location	Purpose
1	Glucose	All the time	Every cell	Keep us alive
2	Glucose and Fructose	Insulin	Pancreas, hypothalamus and liver	Detect glucose
3	Glucose	All the time	Brain	Keep us alive
4	Glucose	Insulin	Fat/Muscles	Provides energy for Muscles and Stores Fat
5	Fructose	When fructose is ingested	Small Intestine	Suck up as much fructose available

The table above basically sets out exactly what these GLUTS do.

ATP (adenosinetriphosphate) is the energy highway of our body.  It stores and transports energy.  The glucose that is dragged into all of our cells through the GLUT receptors is converted to ATP by a chemical reaction involving phosphates and an enzyme.  Every single day every one of us creates and destroys ATP at the equivalent of our total body weight every single day and the energy released by the series of reactions is how we convert glucose into energy. This process is called glycolysis.

In order for glycolysis to take place the cells need an enzyme and different cells use a different enzyme.

The general all purpose enzyme used by all cells is called Hexokinase.  It converts whatever sugar gets sucked into the cell into energy.  GLUTS 1, 3, 4 can only absorb glucose, so where is all the fructose we are now eating absorbed?  The answer is in the liver.

GLUT 2 (located in the liver) is good at sucking up fructose in the liver however the enzyme it uses is fructokinase, not hexokinase and it also doesn’t need insulin to activate, so it sucks it up immediately and rapidly.

GLUT 5 sucks up fructose in the small intestine but as it can only be processed in the liver it gets spat back out of the cell and transported to the liver as that’s the only place it can be utilised.

During the glycolysis process when ATP is created, the enzyme used to create it is called phosphofructokinase or PFK-1.  It’s the gate keeper that stops the liver from making too much energy.  Any excess ATP gets turned into fat so when enough ATP is made PFK-1 deactivates, halting the manufacture of ATP from glucose.  It’s another safety mechanism that the body has to stop generating too much body fat.

The problem with fructokinase is that when it creates ATP, ATP bypasses the glycolysis step that is controlled by PFK-1.  Our body continues to manufacture ATP so long as there is a steady supply of fructose in our blood stream and overloads our cells with ATP.  To counteract this, the body converts all excess ATP into circulating fatty acids.

If we eat an apple, you get a very small amount of fructose.  When you drink a can of soft drink, you get a very large amount of fructose creating vast amounts of circulating fatty acids without the safety mechanisms to stop you eating or drinking when you get full.

Remember we are eating 51 kgs of fructose per person per year in Australia.  Compare this to 16 kgs of fructose back in 1933 and you can see how we are eating more fructose than ever before.

So what happens to all that fructose that we eat? 

It gets rapidly; totally, uncontrollably and immediately converted to circulating fatty acids that avoids all of our internal control mechanisms in the process.  Remember when we eat proteins and carbohydrates, insulin and glucagon control our eating.  When we eat fat CCK controls our eating.  There is no equivalent control mechanism for fructose.  When we ate fructose in fruit there are enough receptors in the pancreas to trigger an insulin response.  Its only when we over consume fructose in the form of soft drinks, fruit juices, sugar laden cereals and every other processed food that its managed to find its way into, that this loop hole in our appetite control mechanism opens up.

SUMMARY:

Wow, that’s a lot to absorb, so let’s just recap.

The hypothalamus is the primary appetite control centre.  It reacts to four major appetite hormones Insulin, Leptin & CCK (when we are full) and ghrelin temporarily inhibits them enabling us to eat when we are hungry.

Proteins, carbohydrates and fats stimulate these hormones when we eat real whole foods.

When we eat fructose in the form of soft drinks, cereals, breads, sauces, biscuits, cakes, chocolates, lollies, fruit juices, sports drinks and all fast food takeaways we are consuming fructose in either sugar form (glucose + fructose) or as in the case of the USA, High Fructose Corn Syrup (HFCS) Fructose does NOT stimulate these hormones.

It skips the fat creation control mechanism in the liver and directly converts to circulating fatty acids without passing through our major appetite control gateways.  It is also invisible to our built in calorie counter.  We can eat as much fructose as we can stuff in our mouths and never feel full for long and every gram of fructose that you eat is immediately, rapidly, directly and uncontrollably converted into fat and stored!

WHATS COMING UP?

Next week, we’ll take a close look at how this same sugar that is making you FAT is also making you SICK.  It’s becoming increasingly proven in the scientific literature available that it is the sugar in our diets and not the fat that is causing those diseases like type II diabetes, cardiovascular disease, strokes and most cancers.

In week three, we will show you what you can do to eliminate sugar from your diet, go back to eating real whole foods and kick that addiction (yes just like alcohol and tobacco sugar is addictive, and the food manufacturers know this)

Till next week!