Home
>
Nutrition
>
Fructose Short-Circuits Glycolysis

Fructose Short-Circuits Glycolysis

First some terminology.

Fructose ... a five carbon sugar that occurs naturally in fruit, does not cause as much insulin to be secreted as glucose and tastes sweeter than glucose.

Glucose ... a six carbon sugar that is the breakdown product of glycogen(a polymer of glucose, multiple glucose units hooked together) that occurs naturally in potatoes and grains.

Glycogen ... multiple units of glucose hooked together (a polymer). What is typically called "complex carbohydrate" today.

Glycolysis ... derived from the Greek stem glyk- "sweet" and lysis meaning dissolution. The metabolic pathway for the initial utilization of glucose.

Phosphofructokinase ... the enzyme that catalyzes the reaction of fructose 6-phosphate to fructose 1,6-biphosphate. You don't need to understand anything more about this reaction other than the fact that if fructose comes from a source other than the degradation of glucose, it blocks this step for glucose until all the non-glucose derived fructose has been metabolized.

Glucose and Fructose Are Both Metabolized via Gylcolysis

Both fructose and glucose are metabolized via glycolysis. Both end up at some point as three carbon fragments. In order for glucose to be broken down into three carbon fragments it must first be metabolized to a five carbon sugar, actually fructose. This is where the trouble starts, since fructose is already a five carbon sugar. The following analogy I hope will aid in explaining this. The analogy, however, is far from perfect.

Whether we start out with separate glucose and fructose as in high fructose corn syrup or honey, or with fructose and glucose hooked together as in sucrose(common table sugar), makes no difference. As soon as sucrose hits the bloodstream, it is immediately broken down (hydrolyzed) to fructose and glucose.

Freda Fructose gets married to Gary (Glucose) Sucrose. They live happily on Sugar Lane. Both work in muscle and liver cells where they are metabolized usually into fat and slow the immune system to a crawl. They get up early in the morning and both have to get on the Glycolysis Road to get to work. Gary (Glucose) is one carbon atom heavier than Freda Fructose and because of that, he cannot cross the river on one of the lighter and faster bridges on their way to work. Freda Fructose however, being lighter, has no problem crossing the faster bridge and making the short-cut to the Glycolysis Road. Gary Glucose, however, has to get on the road well above the short-cut, since he is too heavy to take the lighter bridge short-cut.

The Phosphofructokinase Intersection

As usual Freda Fructose gets to the Phosphofructokinase intersection well before Gary Glucose. By the time Gary Glucose gets to the intersection, the traffic directing policeman is once again allowing all the Freda Fructoses to make the turn onto Glycolysis Road while, all the Gary Glucoses can do is sit in traffic and wait. Once again, Gary, and all the other Glucoses on their way to work, must sit and wait for all the Freda Fructoses to get on Glycolysis Road before they can continue.

LA Traffic Control

Traffic control sees all these Glucoses sitting stuck in traffic, just like traffic backs up everyday in LA. It reacts by injecting a lot of green lights (insulin) into the pathway for the Glucoses to get to work. Finally, all the Fructoses pass and now because there are too many green lights, all the Glucoses pass quickly. All of the sudden there are no Glucoses to be found on the Glycolysis Road. All the cells along the way that used to be able to snag some Glucose can't because there isn't any. Whether it is the excessive insulin that is the cause of so many of the lifestyle diseases we see today or, all the backed up Gary Glucoses decide to cause their own damage to the arteries they are in, I don't know. It is however, clearly established that the ingestion of sucrose (fructose and glucose) is related to many of our lifestyle diseases today including the extensive damage to the vascular system that occurs with adult onset diabetes mellitus. I know, my damaged arteries are up on this site.

Hypoglycemia

Now you begin to feel lightheaded, dizzy and a bit disoriented. Traffic control has injected too many green lights and the concentration of glucose drops precipitously. The brain starts to complain because it no longer has enough glucose to function. If the blood sugar gets low enough, serious complications can occur.

Fructose and Glucose Together

The combination of fructose and glucose should be avoided as much as possible. When you eat your fruit, try to allow at least an hour or preferably two, before eating potatoes, whole grains or rice. Also avoid as much as you can sucrose, high fructose corn syrup, honey and maple syrup or, any sweetener that has as it main ingredients, fructose and glucose.

Other Sweeteners

Brown Rice Syrup

Brown rice syrup is roughly about 45% maltose (two glucose units hooked together), 50% complex carbohydrates and 3% glucose. No glucose and fructose together but still sweet and I have known some people who can even get hypoglycemic from it.

Barley Malt Syrup

Made from whole barley it is about 65% Maltose and 30% complex carbohydrates.

Fruit Concentrates

These are usually combinations of glucose, fructose and sucrose and should be avoided.

Maple Syrup

Maple syrup is about 65% sucrose and should be avoided.

Today's Health Tip:

If you want sweet, you are safest with stevia. Next would be sweeteners derived from rice and barley. Sucrose, high fructose corn syrup, maple syrup and fruit juice concentrates should be avoided.

Reference:
Stryer Biochemistry Fourth Edition

**************
To really get off of sweets and "deprogram a sugar-coated palate," the MericleDiet is hard to beat. Generous servings of organic complex carbohydrates will keep you and your brain happy. To visit the MericleDiet follow the link below.
http://www.drmericle.com
**************

One of our readers Wendy in the UK writes:

Just to let you know that according to the website below that takes you to Carol Bond Health Foods it is spelt Stevita. I couldn't find it anywhere on the site and through asking the chat section it was spelt differently. Thought you would like to know so that you can let the other newsletter recipients know.
Regards...
Wendy

PS Really enjoy the newsletter. Find it very informing so thank you. Gave up drinking milk last year after reading your article! Feel much healthier as a result.
**************

To take Stevia for a test drive or purchase some online follow the link below. I had luck just searching stevia but you could also search the product "Stevita."
http://www.drmericle.com
Thanks for your time.

DrMericle.com is devoted to achieving optimal health and peak performance through diet and lifestyle change. Dr. Mericle brings together a unique blend of formal training in organic chemistry and biochemistry, medical education, 29 marathons, 3 Hawaii Ironman competitions and a lot of practical real life experience.

personalized cleaning services Des Plaines ..

In The News:

Petco disclosed a data breach exposing customer Social Security numbers, financial account details, and driver's license information due to a software error.

Baseball teams can now analyze complete swing mechanics in normal training environments using Theia's markerless AI system that processes standard high-speed footage.

Smart home hacking fears overblown? Expert reveals real cybersecurity risks and simple protection tips to keep your connected devices safe from hackers.

MIT develops needle-free glucose monitor using light technology. Revolutionary device could replace painful finger pricks for diabetes management.

The ClickFix campaign disguises malware as legitimate Windows updates, using steganography to hide shellcode in PNG files and bypass security detection systems.

Researchers from Osaka Metropolitan University designed a 21-foot dome that combines aquaculture and hydroponics to create a self-sustaining urban food system.

The Fox News AI Newsletter gives readers the latest AI technology advancements, covering the challenges and opportunities AI presents.

ChatGPT data breach exposes personal info of users through partner Mixpanel. OpenAI confirms names, emails compromised in security incident.

Android rolls out Emergency Live Video for 911 calls, letting dispatchers see real-time scenes during emergencies. Great for holiday travel safety.

Malicious Chrome and Edge extensions collected browsing history, keystrokes and personal data from millions of users before Google and Microsoft removed them.

Google's new Call Reason feature lets Android users mark calls as urgent before dialing, displaying an urgent label to recipients using Phone by Google app.

Medical history made as surgeons successfully restore sight to legally blind patient using world's first 3D printed corneal implant grown from human cells.

Data brokers aggressively collect your holiday shopping data to fuel scams and targeted ads. Learn how to delete your digital profile before 2025 starts.

Scammers are sending fake MetaMask wallet verification emails using official branding to steal crypto information through phishing links and fraudulent domains.

Learn what background permissions, push notifications, security updates, auto-join networks and app refresh mean to better manage your phone's privacy settings.

Criminals test stolen data by applying for deposit accounts in victims' names to prepare bigger attacks. Learn why banks won't share fraud details.

New study of 10,500+ kids reveals early smartphone ownership linked to depression, obesity, and poor sleep by age 12. Earlier phones mean higher risks.

A phone phishing attack compromised Harvard's alumni and donor database, marking the second security incident at the university in recent months.

AutoFlight's zero-carbon floating vertiport uses solar power to charge eVTOL aircraft while supporting emergency response, tourism, and marine energy maintenance.

A new phone return scam targets recent buyers with fake carrier calls. Learn how criminals steal devices and steps to protect yourself from this fraud.

New Anthropic research reveals how AI reward hacking leads to dangerous behaviors, including models giving harmful advice like drinking bleach to users seeking help.

The Fox News AI Newsletter gives readers the latest AI technology advancements, covering the challenges and opportunities AI presents.

Holiday email scams, including non-delivery fraud and gift card schemes, spike in November and December, costing victims hundreds of millions, the FBI says.

Holiday visits offer the perfect opportunity to help older parents with technology updates, scam protection and basic troubleshooting skills for safer digital experiences.

Swiss scientists create grain-sized robot that surgeons control with magnets to deliver medicine precisely through blood vessels in medical breakthrough.

Fructose Short-Circuits Glycolysis

Nutrition