White table sugar is called sucrose and it's actually made up of two simple sugars bonded together with a weak chemical bond. The 2 sugars are glucose and fructose. They have the exact same chemical formula (C6H12O6) but that is where the similarity ends. They have very different structures and are treated very differently in the body. Fructose is a poison that has turning the worlds population obese. Since the 1960's sugar and high fructose corn syrup has been added to the majority of processed foods. Once upon a time we had the choice to sweeten food, but now we simply cannot avoid it. Just look at a burger meal, the ketchup is full of sugar, the mustard is full of sugar, the bun has sugar in it so that it browns and has a long shelf life, the bacon rasher will be cured with sugar, the burger meat can have sugar in to help the browning. Even the processed cheese slice contains sugar!
Sucrose is a polysaccharide and your body cannot absorb polysaccharides, so it must first break sucrose down into its component parts. Through a process called hydrolysis, water assists in breaking the bond to separate the glucose and fructose molecules; one molecule of water is needed for each molecule of sucrose. They also split in a perfect 50:50 ratio.
Glucose can be absorbed and processed in every cell throughout the body. Your "blood sugar" is actually glucose and it is controlled by insulin which is released by the pancreas when the body senses glucose. When glucose levels starts to rise the insulin triggers your cells to take in the glucose as energy or converts it into glycogen which is stored in the liver and muscles (your "energy battery").
If you ingest 100g of glucose, 80g is used by cells and 20g will hit the liver. The liver will convert a chunk of this to glycogen and the remainder will go into energy production via the citric cycle. Excess citrates can be released by the liver cells mitochondria via the "citrate shuttle" and this produces fatty acids and fat via VLDL. But this is a tiny fraction of the total glucose originally ingested.
Glucose triggers the hunger hormone Ghrelin and also triggers the production of insulin (which produces a leptin response which regulates energy intake and fat stores). After you eat breakfast you don't immediately start eating lunch!
Glucose can be dispersed throughout the body for use as energy, but fructose is targeted like a guided missile to the liver as it's the only place it can be metabolised. Your body does not need fructose to survive.
If you ingest 100g of fructose, zero is used by cells and 100g will hit the liver. Some fructose is converted into glycogen in the liver which then follows the same pathway as glycogen to enter glycolysis. Fructose is metabolized by phosphorylation, a process that bypasses the rate-limiting phosphofructokinase step. Due to the large amounts of fructose the liver has to deal with, there is an increase in uric acid (causes gout) and a large amount is processed into the citric cycle which ultimately makes fat. When ATP levels are high in the cell, the cell no longer needs metabolic energy production to occur, so fat is made.
Excess citrates can be released by the liver cells mitochondria via the "citrate shuttle" and this produces fatty acids and fat via VLDL. But this is a tiny fraction of the total glucose originally ingested. Fructose does not suppress the hunger hormone Ghrelin so you will continue the desire to eat. Fructose does not trigger the production of insulin and so does not produce a leptin response.
High Fructose Corn Syrup (HFCS )
HFCS is made from corn. Whilst sucrose is one molecule of glucose bonded to one molecule of fructose, HFCS is a variable mix of glucose and fructose so it does not need to be hydrolysed in the body. The most common variants have 42% or 55% fructose.
- Table sugar results from the industrial processing of sugar beets or sugar cane. In contrast, high-fructose corn syrup, or HFCS, comes from highly processed corn.
- HFCS and sugar behave in the same manner once ingested. They behave in the same way nutritionally.
- HFCS can be sweeter than sugar. It is also way sweeter than glucose.
- HFCS is stable in acidic foods and beverages and extends the shelf life.
- HFCS is cheaper than sugar (HFCS42 is 50% and HFCS55 is 70% of the cost of sugar). HFCS 55 is mostly used in soft drinks and will give your liver plenty of work to do.
- HFCS can be pumped from food factory storage tanks as a syrup, requiring only simple dilution before use.
Added sugar is hiding in lots of foods that we consider healthy, like yogurt and breakfast cereals. It is also added to savory foods, such as ketchup, breads, salad dressing and pasta sauce. The food companies are very sneaky and use a combination of 60 names for sugar in labels! HFCS is often called "Corn Sugar".
An apple or a carton of apple juice?
A typical small carton of apple juice (lunch box style) can be bought at every convenience store. It will sadly be made from concentrate and be packed with flavourings, preservatives and HFCS. Coca cola has 10.6g/100ml of sugar and apple juice can be as much as 14g/100ml. So a small carton can contain nearly 5 teaspoons of sugar. The juice will also have no fibre or goodness.
An apple contains about 10g of fructose, however it eaten with fibre so the delivery to the liver is slowed.
Foods that often contain HFCS
- Candy and chocolate
- Low fat Yogurt
- Salad Dressing
- Frozen meals
- Canned Fruit
- Juices (eg orange or apple)
- TV Dinners
- Granola Bars
- Breakfast Cereal
- Bakery Goods
- Sauces and Condiments
- Snack Foods
- Cereal Bars
- Nutrition Bars
- Coffee Creamer
- Energy Drinks and Sports Drinks
- Jam and Jelly
- Peanut Butter
- Ice Cream
Shocking fructose levels in soft drinks and juices
Actual fructose consumption levels are difficult to estimate because of the unlabeled quantity of fructose in beverages. A 2014 study shows fructose levels way higher than was thought. Popular beverages made with HFCS have a fructose-to-glucose ratio of approximately 60:40, and thus contain 50% more fructose than glucose. Some pure fruit juices have twice as much fructose as glucose. Shocking!!!
|Fructose %||Glucose %||Fructose g/litre|
|Coca-cola||59.4%||39.6%||62.5g (total sugars: 105.2g)|
|Pepsi||60%||40%||65.7g (total sugars: 109.5g)|
|Dr Pepper||60.2%||38.8%||61.4g (total sugars: 102.0g)|
|Sprite||60%||39%||62.5g (total sugars: 104.2g)|
|Mountain Dew||59.5%||39.6%||72.3g (total sugars: 121.5g)|
|Iced Tea||59.4%||39.6%||59.3g (total sugars: 99.8g)|
|Tonic Water||55%||45%||49.0g (total sugars: 89.0g)|
|Red-Bull||55%||45%||55.0g (total sugars: 100.0g)|
|Tropicana Orange Juice||52%||48%||52.4g (total sugars: 99.5g)|
|Apple Juice (Minute Maid)||67%||33%||73.4g (total sugars: 109.6g)|
|Oceanspray Cranberry Juice||58.4%||41.6%||59.0g (total sugars: 99.4g)|
There are 4g of sugar in a sugar lump. So drinking 1 litre of Pepsi equates to 27 sugar lumps (the equivalent of 18 lumps are fructose which would go straight to the liver).