Why is Agave perceived to be good for you and HFCS is not?
This seemed like a fun research project at the time, but with a myriad of articles out there I got caught in a bit of a sugar hairball about the Good the Bad and the Ugly!
This seemed like a fun research project at the time, but with a myriad of articles out there I got caught in a bit of a sugar hairball about the Good the Bad and the Ugly!
- Both are low glycemic = Good,
- HFCS has got a lot of bad press recently = Bad
- Agave = Ugly (or complicated and confusing because it has a high fructose content just like HFCS, but it's low glycemic)
To help me form an opinion on whether Agave is a good guy or a villain, I went back to undergrad books to familiarize myself with sugar metabolism. My thought was that once I refreshed my understand of the basics I would be able to form an educated opinion regarding the two sweeteners.
This is what I have heard regarding HFCS and Agave;
This is what I have heard regarding HFCS and Agave;
- High Fructose Corn Syrup (HFCS) is "bad", it's highly processed and made by big businesses, it's making our kids fat and will increase health costs because so many people will be suffering from obesity.
- Agave is "good", it's made from a natural ingredients, it's low glycemic, it's sold in health food stores, it must be good for you.
- Both contain a higher percentage of fructose than sucrose (regular granulated sugar)
- Both are low glycemic
- Agave contains only a slightly higher percentage of fructose than HFCS (they sound pretty similar to me)
I reviewed some simple carbohydrate chemistry...
- Some simple sugars are glucose, fructose, mannose and galactose, there are also called monosaccharides.
- Molecules made of 2 simple sugars are called disaccharides, here are some examples of disaccharides;
- Sucrose = Glucose + Fructose (regular table sugar)
- Maltose = Glucose + Glucose
- Lactose = Glucose + Galactose
- When more sugars are linked together they are called polyscahrarrides, examples are amylose and celulose.
- All of the above are carbohydrates.
General note: Throughout this blog I have tried not to use the generic term "sugar" and use sucrose, glucose, fructose, etc. Not all sugars are the same, they have different levels of sweetness, they are metabolized differently and have different affects on your body. The terms "sugar rush", or "low blood sugar" are confusing, we should really be saying "glucose rush" and "low blood glucose" level.
Sucrose (table sugar), Agave and HFCS are comprised of glucose and fructose, in different amounts, so I decided to look at those monosaccahrides in more detail.
Glucose - It's Brain Food
- Glucose is the only sugar used by the brain (not fructose)
- Because neurons cannot store glucose, they depend on the bloodstream to deliver a constant supply of this precious fuel.
- Digestion in the body revolves heavily around supplying the brain with glucose - food is broken down so glucose is readily available to the brain
- Alcohol is metabolized by an enzyme "alcohol dehydrogenase" that also inhibits the digestion of sugars...so essentially excess alcohol can reduce glucose levels to a point were the body gets a little concerned about feeding the brain and so induces hunger. That's why it always seems like a good idea to go for a curry or bean burrito at 1am in the morning after a night of heavy partying :-) Next time you can truthfully say "I need a cheese burger, stat! It's for my brain!"
An Enzyme called Insulin
So glucose being the brain fuel, you'd think that more glucose would make you a super brainy person, right? Actually too much glucose causes sugar glucose highs followed by glucose lows, shaky hands and brain fog....how charming!
When there is too much glucose in your bloodstream your body reacts
...it must lower levels, it must store excess for low glucose situations
So when you eat something very high in glucose you become hyperglycemic (higher glucose). This sugar can make you feel happy (higher glucose = sugar high). However, a quick jump in blood glucose levels will alert islet cells in your pancreas to secrete insulin. The insulin flows through your bloodstream and triggers cells throughout your body to pull the excess glucose out of your bloodstream and store it for later use. http://www.fi.edu/learn/brain/carbs.html The cells are very efficient and can very quickly reduce blood glucose levels to the point where neurons in your brain detect the rapid decrease of glucose and it's availability to your brain.
When there is too little glucose in your bloodstream your body reacts
...it must get glucose to feed the brain
Neurons that are unable to store glucose, experience an energy crisis. You feel spaced-out, weak, confused, and/or nervous. Your ability to focus and think suffers. The name for this glucose deficiency is hypoglycemia (low sugar glucose), and it can even lead to unconsciousness if you are diabetic. Your brain needs glucose from something you eat or from stores within the body and this is controlled by Insulin.
Insulin is a hardworking enzyme, it has an important job working to keep optimum sugar levels. Too much sugar in the bloodstream is not good for you. http://en.wikipedia.org/wiki/Hyperglycemia The excess glucose molecules floating around will attach to proteins and fats in a process called glycosylation (http://en.wikipedia.org/wiki/Glycosylation). When glucose bonds with blood vessels and your internal organs it can reduce blood flow to extremities and even blindness. This is what could happen if you have diabetes and don't regulate your insulin and glucose levels.
This is the simplified "Clifs notes" version and we could go much deeper into the metabolic science, but for the purpose of this post we just need to understand these point;
...it must lower levels, it must store excess for low glucose situations
So when you eat something very high in glucose you become hyperglycemic (higher glucose). This sugar can make you feel happy (higher glucose = sugar high). However, a quick jump in blood glucose levels will alert islet cells in your pancreas to secrete insulin. The insulin flows through your bloodstream and triggers cells throughout your body to pull the excess glucose out of your bloodstream and store it for later use. http://www.fi.edu/learn/brain/carbs.html The cells are very efficient and can very quickly reduce blood glucose levels to the point where neurons in your brain detect the rapid decrease of glucose and it's availability to your brain.
When there is too little glucose in your bloodstream your body reacts
...it must get glucose to feed the brain
Neurons that are unable to store glucose, experience an energy crisis. You feel spaced-out, weak, confused, and/or nervous. Your ability to focus and think suffers. The name for this glucose deficiency is hypoglycemia (low sugar glucose), and it can even lead to unconsciousness if you are diabetic. Your brain needs glucose from something you eat or from stores within the body and this is controlled by Insulin.
Insulin is a hardworking enzyme, it has an important job working to keep optimum sugar levels. Too much sugar in the bloodstream is not good for you. http://en.wikipedia.org/wiki/Hyperglycemia The excess glucose molecules floating around will attach to proteins and fats in a process called glycosylation (http://en.wikipedia.org/wiki/Glycosylation). When glucose bonds with blood vessels and your internal organs it can reduce blood flow to extremities and even blindness. This is what could happen if you have diabetes and don't regulate your insulin and glucose levels.
This is the simplified "Clifs notes" version and we could go much deeper into the metabolic science, but for the purpose of this post we just need to understand these point;
- Glucose is the only fuel used by your brain
- Too much glucose at one time is bad as it causes insulin to be released into the bloodstream, insulin collects the excess sugars and stores them for future use (in fast releasing glycogen and long term storage fat cells)
- Too little insulin allows high blood sugar levels, the excess sugars stick to internal organs and cause blockages
- The speed at which glucose is released into the bloodstream is important as that will determine whether Insulin is needed or not
- Different foods release glucose at different speeds; Glycemic index (GI)
- There is a specific glycemic index number that initiates an insulin response - you should know what this is and roughly what foods are above and blow that number
If glucose affects insulin levels, fat storage, sugar glucose rush and brain fog it almost sounds like we should try a different type of sugar that doesn't cause all these problems. Say, fructose? The GI table below would certainly suggest that.
The Glycemic Index (http://en.wikipedia.org/wiki/Glycemic_index) is a ranking of foods based on their overall effects on blood sugar glucose levels. The higher the GI the faster the sugar is metabolized and the faster glucose is release into the bloodstream. This is good for energy recovery after endurance exercise or for a person with hypoglycemia (low glucose levels). In general a glycemic index of over 70 will initiate an insulin response to go an sequester excess glucose in the bloodstream.
The following list gives ranges for low, medium and high glycemic load for foods.
- Low GI = 55 or less
- Medium GI = 56 - 69s
- High GI = 70 or more
Glucose the monosaccharide has a GI of 96
http://www.fitsugar.com/Glycemic-Index-Where-Do-Sweeteners-Fall-3031565
Fructose the monosaccharide has a GI of 22
Honey (http://en.wikipedia.org/wiki/Honey) has the same sweetness as sucrose and has a glycemic index range from 31 to 78, depending on the variety; generally a GI of 55 is used as an average Honey is comprised of mainly glucose and fructose in these approximate quantities 31% glucose to 38% fructose.
Agave sweeteners are sweeter than sucrose and have a low GI of approximately 30.(http://www.cooking-questions.com/what-is-agave-nectar/) . Depending on the source the levels of glucose to fructose are in the following ranges; 8% glucose to 92% fructose, and 20% glucose to 56% fructose (http://en.wikipedia.org/wiki/Agave_nectar).
HFCS is also sweeter than sucrose and has a low GI of approximately 62. HFCS is comprised of 45 glucose to 55% fructose, though there is also HFCS 65 that has 65% fructose.
Coconut Sap http://www.bigtreefarms.com/coconutsugar/ has a GI of 35 and is comprised of the disaccharide sucrose (70-79%) plus glucose and fructose (3-9%) each.
Getting back to the comparison of Agave with HFCS...
Fructose tastes sweeter than glucose, so you need less to achieve the same sweetness plus you get fewer calories. Fructose is also the main sugar that makes fruit taste sweet. What's not to love about fructose?
- Both Agave and HFCS have more fructose than glucose
- Lower glucose percentage means they have a lower glycemic index
- Lower glycemic index means a lower insulin response so no brain fog or massive glucose sequestering and filling of fat cells
We have talked about high and low blood sugar glucose in the bloodstream; when glucose levels are high, the blood glucose police call out the insulin bouncers to round up all the excess glucose molecules loitering around. They take those rowdy glucose dudes and lock them up in cells, yes, you guessed it...."Fat Cells!".
Just like you don't want to annoy regular law enforcement, you don't want to agitate the blood sugar police either! And you do not want any bouncers filling up your fat cells!
We've learned some of the difference between glucose and fructose but there is more....
Fructose - The Sweet One
A lot about fructose has already been discussed in comparisons with glucose, but we need to know how it is metabolized, does it have a comparable regulator like insulin, what does the body do with fructose? Or should I ask, what does fructose do to the body?
Fructose (http://www.asn-online.org/press/files/johnsonreview.pdf) is absorbed into the intestine were there are various transporter enzymes. About 60% of the fructose attaches to transporter enzymes that bus them to the liver, the remaining 40% catch transporters en route to the kidneys, adipose tissue and other organs.
Fructose is ultimately metabolized to uric acid, in this pathway the enzyme fructokinase adds a phosphate to Fructose. This causes the depletion of ATP and so this process is regulated by ATP availability...blah, blah, blah.. I'll try and keep it simple...
At the beginning I asked the question - Why is Agave perceived to be good for you and HFCS is not? The only answer I can give regarding why agave is better is agave is not genetically modified, whereas the corn used in HFCS probably is. But neither of them are "good" for you due mainly in part to their high fructose levels.
What I now think about HFCS and Agave;
Just like you don't want to annoy regular law enforcement, you don't want to agitate the blood sugar police either! And you do not want any bouncers filling up your fat cells!
We've learned some of the difference between glucose and fructose but there is more....
Fructose - The Sweet One
A lot about fructose has already been discussed in comparisons with glucose, but we need to know how it is metabolized, does it have a comparable regulator like insulin, what does the body do with fructose? Or should I ask, what does fructose do to the body?
Fructose (http://www.asn-online.org/press/files/johnsonreview.pdf) is absorbed into the intestine were there are various transporter enzymes. About 60% of the fructose attaches to transporter enzymes that bus them to the liver, the remaining 40% catch transporters en route to the kidneys, adipose tissue and other organs.
Fructose is ultimately metabolized to uric acid, in this pathway the enzyme fructokinase adds a phosphate to Fructose. This causes the depletion of ATP and so this process is regulated by ATP availability...blah, blah, blah.. I'll try and keep it simple...
- High uric acid levels are related to hypertension (elevated blood pressure)
- Comparative experiments with equal amounts of fructose and glucose show that fructose, not glucose, increased blood pressure in young healthy adults
- Individuals given fructose exhibit features of metabolic syndrome - Metabolic syndrome is a name for a group of risk factors that occur together and increase the risk for coronary artery disease, stroke, and type 2 diabetes. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004546
- Excessive amounts of fructose have been shown to increase blood triglyceride levels and reduce HDL (good) cholesterol levels
- Fructose is also known to induce insulin resistance, this will reduces blood flow and the delivery of glucose to the brain, peripheral tissues and muscles
- The hypertensive affects of fructose is also thought to have a role in chronic kidney disease
At the beginning I asked the question - Why is Agave perceived to be good for you and HFCS is not? The only answer I can give regarding why agave is better is agave is not genetically modified, whereas the corn used in HFCS probably is. But neither of them are "good" for you due mainly in part to their high fructose levels.
What I now think about HFCS and Agave;
- High Fructose Corn Syrup is a processed syrup made from corn, it's low glycemic and if eaten in excessive quantities it can make you fat and put serious stress on your liver and kidneys
- Agave is a processed syrup made from the agave root, it's low glycemic and if eaten in excessive quantities it can make you fat and put serious stress on your liver and kidneys
My personal opinion is high fructose sugars should not be your sweetener of choice. They are good because they have a lower GI than sucrose and don't invoke a massive insulin response, but the risks outweigh the benefits for me. I will not completely omit them from my diet but I will severely reduce them.
...And if you're interested....
What will be my sweetener of choice?
I will continue to use stevia and fruit juices, but when I need a granular sugar I will use coconut palm sugar. Palm sugar has a lower GI than sucrose and it has less fructose than sucrose. I am however, concerned about the sustainability of palm sugar, so I will need to research that while I continue to explore other natural sweeteners.
Please don't hate the messenger, I know how people love agave...just be responsible with it, please!
Other links collected during my research
I will continue to use stevia and fruit juices, but when I need a granular sugar I will use coconut palm sugar. Palm sugar has a lower GI than sucrose and it has less fructose than sucrose. I am however, concerned about the sustainability of palm sugar, so I will need to research that while I continue to explore other natural sweeteners.
Please don't hate the messenger, I know how people love agave...just be responsible with it, please!
Other links collected during my research
The Truth about Agave Syrup: Not as Healthy as You May Think
Agave Nectar, the High Fructose Health Food FraudLearn more: http://www.naturalnews.com/024892_fructose_food_health.html
Is Agave Nectar More Hype Than Healthy?
Agave Nectar: Low Glycemic Diet Blessing or Nightmare? http://www.associatedcontent.com/article/6094960/agave_nectar_low_glycemic_diet_blessing.htm
It is low glycemic so it won't cause a spike insulin levels
Agave Nectar and the Glycemic Index
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