Fructose, friend or foe?

Fructose, otherwise known as the sugar found in fruit, it's in honey and is sweeter than sucrose.  It is used in many foodstuffs and in medicine, mainly in a solution form as an intravenous "nutrient".

Lots of people believe that fructose is "healthier" because... well... it's from fruit and fruit is healthy, right?

Well yes, fruit is healthy when you eat the WHOLE fruit with all that healthy fiber, then the fructose does not have a negative effect on your body.

But, take the fructose out of the fruit and it turns into something different and far more dangerous - think High Fructose Corn Syrup (HFCS).

But first, let's take a look at the differences between the 3 main sugars in our lives:

GLUCOSE:

Glucose is the most important monosaccharide and the body's preferred sugar.  Glucose is also called blood sugar as it circulates in the blood and relies on the enzymes glucokinase and hexokinase to initiate metabolism.  The body processes most carbohydrates into glucose for immediate use or to be stored in the muscles or liver as glycogen for later use.

When elevated blood levels of glucose are detected, insulin is secreted facilitating the entry of glucose into cells.

FRUCTOSE:

As stated above, fructose is found naturally in fruits and vegetables, but it is also added to many foodstuffs including soda and fruit-flavored drinks.  However, it has a different metabolic pathway from other sugars, and is NOT the preferred energy source for brain and muscles.

Fructose is only metabolized in the liver and needs fructokinase to initiate metabolism.  Fructose is also more lipogenic - fat producing, compared to glucose.  It also does not induce the secretion of insulin or stimulate the production of leptin - a key hormone for regulating energy intake and expenditure.  This suggests that fructose behaves more like fat in the body than like other carbohydrates.

SUCROSE:

Also known as table sugar, fruits and vegetables also naturally contain sucrose.  When sucrose is
consumed the enzymes beta-fructosidase separates the sucrose into glucose and fructose.  Once separated, they each follow their particular metabolic pathways.  However, although they are ingested at the same time, the body prefers to use the glucose as its main energy source, and if it doesn't need the energy provided by the fructose, then it will convert it into fat stimulated by the insulin secreted in response to the glucose.

Glucose is essential for life.  Our bodies produce it and every living cell contains it.

Fructose, on the other hand, is NOT essential for life, the body doesn't produce it and throughout history, has only ever consumed it in its natural fruit form - until, that is, they started adding it to food...

So, how can fructose harm you?

Well, having a diet high in fructose can cause problems to your health such as; increased levels of uric acid which in turn leads to gout and high blood pressure.  It can also cause fatty liver which can lead to non-alcoholic fatty liver disease.  Insulin resistance which can lead to type 2 diabetes is another issue and fructose does not affect satiety in the same way that glucose does, leading to eating more than is necessary.  Scientists at the university of Barcelona have found that fructose contributes to raising the risk of obesity, diabetes, heart disease and stroke.

They carried out studies on rats using two types of simple sugars.  The group of rats given fructose water put on more weight than those given glucose water.  Their results were published in the American Journal of Physiology Heart and Circulatory Physiology, stating that the fructose rats suffered more damaging effects on their metabolism and vascular system, fatty liver and an increased risk of obesity.

This means you need to read the labels on the food you buy... in fact, if it has a label, don't buy it!

I can help you improve your health.  If you would like to make an appointment with me either in person or via Skype, just send me an email to lucycarr@socialnutrition.com

The Fructose Controversy

There is fructose and there is High Fructose Corn Syrup (HFCS).

The definition in Wikipedia for Fructose says: Fructose or fruit sugar is a simple monosaccharide found in many plants.  It is one of the three dietary monosaccharides, along with glucose and galactose that are absorbed directly into the bloodstream during digestion.  Fructose was discovered by French Chemist Agustin-Pierre Dubrunfaut in 1847.  Pure dry fructose is a very sweet, white, odorless, crystalline solid and is the most water soluble of all the sugars.  From plant sources, fructose is found in honey, tree and vine fruits, flowers, berries, and most root vegetables.  In plants, fructose may be present as the monosaccharide and/or as a molecular component of sucrose, which is a disaccharide.

The definition in Wikipedia for High Fructose Corn Syrup (HFCS) says:  HFCS - also called glucose-fructose syrup in the UK, glucose/fructose in Canada, Glucose/Fructose syrup in the EU and high-fructose maize syrup in other countries - comprises any of a group of corn syrups that has undergone enzymatic processing to convert some of its glucose into fructose to produce a desired sweetness.  In the United States, consumer foods and products typically use HFCS as a sweetener.  It has become very common in processed foods and beverages in the US; including breads, cereals, breakfast bars, lunch meats,yogurts, soups and condiments.

HFCS consists of 24% water, and the rest sugars.  The most widely used varieties of HFCS are: HFCS 55 (mostly used in soft drinks), approximately 55% fructose and 42% glucose; and HFCS 42 (used in beverages, processed foods, cereals and baked goods), approximately 42% fructose and 53% glucose.  HFCS 90, approximately 90% fructose and 10% glucose, is used in small quantities for speciality applications, but primarily is used to blend with HFCS 42 to make HFCS 55.

Why is there so much HFCS in our diet?  Well, it all comes down to money.  Food manufacturers discovered that they could save money using HFCS instead of sugar - it is cheaper and has a longer shelf life... but that's where the "benefits" stop, and they are only for the manufacturer.

In humans, the consumption of HFCS is responsible for:

1.  Weight gain and obesity.  HFCS increases hunger so you eat more.
2.  Increased risk of developing Type II Diabetes.  Fructose interacts with the carbonated soft drinks to form carbonyls.  Carbonyls are toxic and are linked to diabetes in children.  HFCS promotes a life time risk for diabetes in children 30% risk for boys and 40% risk for girls.
3.  Hypertension and elevated "bad" cholesterol levels (LDL).
4.  HFCS and longterm liver damage - The liver turns HFCS into fat which is stored in the liver creating a condition known as "Fatty Liver".
5. Mercury exposure from HFCS.
6. Creates Insulin resistance which can lead to deadly strokes and heart attacks.
7.  Metabolic Syndrome.

In 1957 HFCS was invented by a pair of researchers named Marshall and Kooi.  Until that invention people had correctly understood that there is no fructose in corn syrup.  Corn syrup contains a different sugar molecule - glucose - which is considerably less sweet than fructose.  Marshall and Kooi developed an enzyme called glucose isomerase that could rearrange the molecular structure of the glucose in corn syrup, and convert it into fructose.  The syrup became sweeter when the glucose was converted to fructose by the enzyme.  HFCS began to be produced on an industrial scale in the 1970s.

According to a USDA report from 1997 in 1970 sucrose (table sugar) accounted for 83% of sweeteners consumed by Americans and by 1997 sucrose accounted for only 43% the rest was HFCS (=56% of sweeteners consumed by Americans).  In another USDA report covering the period of 1970-2003 showed consumption per capita of sucrose versus HFCS in the United States.  The consumption table showed that sucrose consumption fell rapidly while HFCS consumption climbed steadily.  Dr. Alan Gaby (Nutritional Medical Specialist) said:

"The increase in HFCS consumption far exceeds the increase in intake of any other food or food group."

Diabetes is a chronic disease that inflicts nearly 24 million people in the United States and it is understood that approximately 5.7 million Americans remain undiagnosed and on top of that there are and estimated 57 million pre-diabetics.  Here are the projections for the increase in cases of diabetes by country for the year 2030 according to the World Health Organization (WHO) (For more information per country you can visit Diabetes statistics by country:

Country	2000	2030
Brazil	4,553,000	11,305,000
Colombia	883,000	2,425,000
Ecuador	341,000	921,000
Mexico	2,179,000	6,130,000
France	1,710,000	2,645,000
Germany	2,627,000	3,771,000
Italy	4,252,000	5,374,000
Spain	2,717,000	3,752,000
UK & N.I.	1,765,000	2,668,000

As you can see they are quite worrying figures.

Insulin resistance is the primary problem with diabetes.  HFCS has been shown to increase insulin resistance which means consumption of HFCS will worsen your diabetes if you already have it or if you are pre-diabetic, it can affect your immune system to the extent that it succumbs to the disease.  However, it is a good idea to keep in mind that some of the major risk factors for diabetes (heredity, obesity, a sedentary lifestyle, an unhealthy diet, high cholesterol and high blood pressure) are in your power to change.  A healthier lifestyle which avoids the consumption of HFCS will lower 3 of those risk factors: obesity, high cholesterol and high blood pressure.

Another worrying health problem is metabolic syndrome.  This is a condition characterized by disorders of lipoprotein metabolism (high cholesterol and triglycerides), hypertension, and hyperglycemia (abnormally high concentrations of glucose in blood).  This syndrome afflicts more than 50 million Americans.  Metabolic Syndrome is the result of the continual influx of HFCS products, which creates insulin resistance.

In 2007, a study from Yale University of Medicine stated "Insulin-resistant individuals in their study were found to have their carbohydrate energy rerouted to liver fat production.  This process elevated the participants' blood triglycerides by as much as 60%, while lowering their HDL (good) cholesterol by 20%".

So, as this is turning into a very long post, I'd just like to finish up by saying two things:

1.  There is nothing to gain from the consumption of HFCS - nothing at all.
2.  Please do not confuse HFCS with naturally occurring fructose in fruits, vegetables, breads and grains which are not harmful to the body although HIGH fructose fruits, vegetables, breads and grains should be used in moderation.