... except that which is found naturally.
I know DR. Sears suggests if one adds a sweetener, which we usually avoid, to use Fructose.
But: .....
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The average American consumes 1/3 of a pound of sugars of various types per day. That's five ounces or 150 grams, half of which is fructose, which is 300 percent more Fructose than the amount that will trigger biochemical havoc. And many Americans consume more than twice that amount! Thanks to the excellent work of researchers like Dr. Robert Lustig, as well as Dr. Richard Johnson, we now know that Fructose:
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- Is metabolized differently from glucose, with the majority being turned directly into fat
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- Tricks your body into gaining weight by fooling your metabolism, as it turns off your body's appetite-control system.
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- Fructose does not appropriately stimulate insulin, which in turn does not suppress ghrelin (the "hunger hormone") and doesn't stimulate leptin (the "satiety hormone"), which together result in your eating more and developing insulin resistance.
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- Rapidly leads to weight gain and abdominal obesity ("beer belly"), decreased HDL, increased LDL, elevated triglycerides, elevated blood sugar, and high blood pressure—i.e., classic metabolic syndrome.
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- Over time leads to insulin resistance, which is not only an underlying factor of type 2 diabetes and heart disease, but also many cancers.

Interesting stuff, John!

I used to be a fan of fructose, but have long given that up. I guess my thoughts about it are that frucose is fine when it is built into the fruit that it came from. All of the components of the food work together to provide a healthful treat. However, if fructose is removed from the food and used as a sweetener, it no longer works in synergy with the other components of the food.

Re Lustig's work, from what I saw on the 60 minutes piece in it was discussed her a few weeks ago, he's missed the boat with his sugar theories (see the link posted in this forums to te recent "60 minutes" sugar article). andsince we're discussing this in terms of sharing Zone inrfo, Barry Sears' take on it, which he discussed in detail during his most recent webinar/chat (there's a link posted previously in these forums), agreed with mine.

Since I don't really have the knowledge base that any of the aforementioned scientists have, I generally take the stand that each one is valid--in their own way. Sometimes I can sort it out, sometimes I can't. But, they are the scientists, the researchers, and they know what they are doing. I generally like to take a further look at who is benefitting from the research, who is getting paid to do it, etc. Generally, those who are conducting research at universities (as opposed to research going on privately) tend to hold more validity, but that is just my own opinion. ;)

To be honest with you, as long we are talking about the sort of fructose that occurs naturally in fruits, as opposed to processed sugars added to food like high fructose corn syrup, I think the whole fear of fructose is a little overblown. Okay, if it is a big concern for you, avoid things like figs and raisons and such, but it isn't like people who eat 4 apples a day are the people with large waistlines. It is like people who avoid carrot because they have a relatively high GI for a veggie. Okay, true, the GI might be high, but the total amount of sugar in a carrot really isn't all that much, so as long as you aren't juicing 20 carrots and drinking that it really isn't a big deal. The health benefits of eating a wide variety of fruits and veggies far outweighs whatever minor concerns there might be with Fructose (or a higher GI with carrots, for example). After all, how many grams of fructose are you really getting from eating an apple? Something like 6g or so?

Now, if we are talking about refined, processed food, yeah, this can be an issue. But millions of years of human evolution has pretty much made us well-suited to eating real fruit. While I get the science behind the fructose v. glucose debate, at the end of the day, if you are making healthy food choices, I feel it is a tempest in a teapot.

Also, whatever concerns you may have about adding fructose as a sweetener, it isn't like we are talking about adding a ton of it. Certainly not enough to add much in the way of concern about it going to fat. First, you will be eating it with protein and fat. Second, the other carbs in your meal should be low GI carbs, and given that fructose is a lower GI sugar, this should mean less of an insulin response. Also, your body is burning and storing fat all day long. It is a constant process. As long as you aren't eating a lot of processed foods artificially sweetened with fructose, adding a little here and there, even non-naturally occurring fructose, shouldn't be a big deal. Also, I will most certainly take fructose over any artificial sweetener any day of the week.

More than 25 grams per day is the point at which Fructose is not acceptable.
5 servings of favorable fruit per day is about 25 grams of Fructose.
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Overall, sugar is 50 times more potent than calories, in terms of causing diabetes. But why does it have this extraordinarily potent effect?
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The answer lies in its unique structure. As just mentioned, it metabolizes as both fat and carbohydrate, and the reason for this is because it contains both glucose and fructose. These two sugars are not interchangeable, and your body processes each of them differently.
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Sucrose (table sugar) is 50 percent glucose and 50 percent fructose. High fructose corn syrup (HFCS) is anywhere from 42 to 55 percent fructose depending on which type is used. Glucose is the form of energy your body is designed to run on. Every cell in your body uses glucose for energy, and it's metabolized in every organ of your body; about 20 percent of glucose is metabolized in your liver. Fructose, on the other hand, can only be metabolized by your liver, because your liver is the only organ that has the transporter for it.
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Since all fructose gets shuttled to your liver, and, if you eat a typical Western-style diet, you consume high amounts of it, fructose ends up taxing and damaging your liver in the same way alcohol and other toxins do. In fact, fructose is virtually identical to alcohol with regards to the metabolic havoc it wreaks. According to Dr. Lustig, fructose is a "chronic, dose-dependent liver toxin." And just like alcohol, fructose is metabolized directly into fat—not cellular energy, like glucose. So eating fructose is really like eating fat—it just gets stored in your fat cells, which leads to mitochondrial malfunction.
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Not even fatty fruits like avocado or coconut have this effect, because your body treats them as either a fat or a carb—not both. Sugar is the only food that functions as both a fat and a carb simultaneously, and it is this combination of fat and carb that causes metabolic derangements and, subsequently, disease. So, please, don't be fooled: when it comes to sugar, the claim you hear on TV, that "sugar is sugar" no matter what form it's in, is a misstatement that can, quite literally, kill you—albeit slowly.
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If you want to shed excess pounds and maintain a healthy weight long-term, and RADICALLY reduce (and in many cases virtually eliminate) your risk of diabetes, heart disease and cancer, then start getting serious about restricting your consumption of fructose to no more than 25 grams per day. If you're already overweight, or have any of these diseases or are at high risk of any of them, then you're probably better off cutting that down to 10-15 grams per day.
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Glucose Metabolism: Glucose is a product of photosynthesis and is found in rice, corn and other grains. Once you take in glucose from a meal, 80 percent of it is used by all of the organs of your body; 20 percent goes to your liver to be metabolized and stored. The following is what happens to that 20 percent, once it reaches your liver (this is normal, and how your body was designed to operate):
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Whatever glucose your body doesn't need immediately gets converted into glycogen for storage in your liver. Glycogen can be easily converted to energy when you need it. Your liver has no limit to how much glycogen it can store without detrimental effects.
A small amount of pyruvate is produced, which ends up being converted to ATP (the chemical storage form of energy) and carbon dioxide.
Insulin is released by your pancreas in response to the rise in blood glucose (i.e., blood sugar), which helps the glucose get into your cells. Without insulin, your cells would not be able to process the glucose and therefore would have no energy for movement, growth, repair, or other functions. Insulin is key to unlocking the door of the cell to allow the glucose to be transferred from the bloodstream into the cell.
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When you consume 120 calories of glucose, less than ONE calorie contributes to adverse metabolic outcomes.
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Fructose Metabolism: 100 percent of the fructose you consume goes directly to your liver.
Fructose metabolism creates a number of adverse effects, including:
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Fructose is immediately converted to fructose-1-phosphate (F1P), depleting your liver cells of phosphates. This process produces waste products in the form of uric acid. Uric acid blocks an enzyme that makes nitric oxide, which is your body's natural blood pressure regulator. Hence your blood pressure rises, leading to hypertension. Elevated uric acid levels can also cause gout.
Almost all of the F1P is turned into pyruvate, ending up as citrate, which results in de novo lipogenesis, the end products of which are free fatty acids (FFAs), very low-density lipoproteins (VLDLs are smaller, denser LDLs that get stuck beneath your epithelial cells and stimulate plaque formation), and triglycerides. The end result is hyperlipidemia.
Fructose stimulates g-3-p (activated glycerol), which is the crucial molecule for creating triglycerides within fat cells. The more g-3-p that is available, the more fat is deposited.
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FFAs are exported from your liver and taken up in skeletal muscle, causing skeletal muscle insulin resistance. Some of the FFAs also stay in your liver, leading to fat accumulation, hepatic insulin resistance and nonalcoholic fatty liver disease (NAFLD)
Insulin resistance stresses your pancreas, which pumps out more insulin in response to rising blood sugar as your cells are unable to get the sugar out of your bloodstream, and this can progress to type 2 diabetes.
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When you consume 120 calories of fructose, about 40 calories contribute to adverse metabolic outcomes.

Interesting topic. It looks like pineapples, oranges, cantaloupe, peaches, nectarines and fresh apricots have the lowest amount of fructose, slightly lower than berries. Would this make them slightly more favorable than berries?

Source - http://www.reducetriglycerides.com/..._fruit.htm

The chart also shows bananas to have less fructose than blueberries.

There is more than just the Fructose to making a fruit (food) unfavorable.
(many unfavorable carbs are not fructose based.)
It has to to with the Glycemic Load (not Glycemic Index).
How fast the carbohydrate converts/breaksdown into its sugar(s), thereby spiking insulin.
A lower Glycemic Load, takes more time to breakdown/convert into its basic sugar(s), so the insulin response is slower, more gradual.
I know that banana's are considered (or were) unfavorable.
And only 1/3 of a banana is one block.

The favorability of a food is related to the glycemic index (GI) of that food. The GI of a food cannot be determined by simply looking at the amount of sugars contained in that particular food. Each food has to be individually tested to determine it's GI. For that reason one can't assume the foods you asked about to be more favorable than berries simply by looking at the amounts of sugars they contain. In fact, berries are considered to be the best choice of fruit for the Zone Diet while pineapple and canteloupe are both unfavorable.

John, looks like were composing our replies at the same time. :)

Some more info. The Glycemic Load is a function of the glycemic index and the serving size of the particular food.

Even more info: You can not compare the Glycemic Index of one food to the Glycemic Index of another food.
The Glycemic Load, on-the-other-hand, takes into account (as Sue alluded to) the serving size.
So one can compare the Glycemic Loads of foods against each other.
There are some instances where the Glycemic Index of one food is high, while its Glycemic Load is low.
And vice-versa, a food with a low Glycemic Index could have a high Glycemic Load.
Dr. Sears has taken all of this into account in determining Favorable Carbohydrates.
And some foods (very few) he had revised. Early on Carrots were listed as unfavorable, now they are listed as favorable, for example.

New study:
A high-fructose diet made rats remarkably stupid and unable to easily navigate a maze (the rodent version of an IQ test),
while adding omega-3s counteracted this effect.
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This is your brain on sugar:
UCLA study shows high-fructose diet sabotages learning, memory!
Attention, college students cramming between midterms and finals: Binging on soda and sweets for as little as six weeks may make you stupid.
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A new UCLA study is the first to show how a diet steadily high in fructose slows the brain, hampering memory and learning — and how omega-3 fatty acids can counteract the disruption. The peer-reviewed Journal of Physiology publishes the findings in its May 15 edition.

... rest of article at:
http://earthsky.org/science-wire/th...ing-memory

While studies on rodents certainly raise questions regarding whether fructose has similar effects in human beings, it certainly doesn't answer that question definitively given that rats are not human. Animal studies are all well and good, but I would like to see some human studies showing that fructose makes us stupid. Human beings evolved over millions of years as hunter gatherers for who things like fruits and berries were an important source of nutrition. I am highly skeptical of taking a few isolated bits and pieces of information and a few animal studies and concluding that fruits high in fructose are somehow bad for us.

I am just theorizing here, but I feel that fructose eaten in the form of fruit is probably not as harmful as fructose that has been separated from the fruit and then converted into another form of table sugar.

Agreed! And the details of the study involve man-made/extracted Fructose, and not God provided Fructose naturally in fruits.
There is a difference between substances found naturally in our foods and certain individual substances extracted out, like Fructose.

Addendum:
A recent study found that while stuff like (raw, unprocessed honey, molasses, and (pure) maple syrup all contain significant amounts of antioxidants that potentially mitigate the metabolic damage wrought by the sugar (fructose) therein;
agave nectar – along with refined sugar and corn syrup – has almost none.

Well, if we are talking solely about processed foods here, then I agree. But then I avoid processed foods as much as possible anyways (although not entirely). Other than perhaps whey or casein protein powder I consume very little in the way of processed or extracted foods.

See, we are all in agreement.
Natural, unprocessed, and raw when possible = foods.
"If it rots, eat it".

YUP! Love that one!

Too much Fructose (ingesting much more other than found naturally and in whole raw from in fruit):
Such as pure (man-made/extracted) Fructose as a sugar substitute:
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Question is Fructose, found in fruit, bad for you as a sugar substitute?
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The short answer is yes. I’m not an expert on sugar metabolism, but I’ll tell you what the experts at Harvard Medical School tell me.
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Fructose and glucose are the most abundant sugars in our diet. Such sugars are a source of energy for our cells.
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In the early 1900s, the average American took in only about 15 grams of fructose, also called fruit sugar, a day. Most of it came from eating fruits and vegetables. Today we average four or five times that amount. And almost all of it comes from sweetened foods and beverages such as breakfast cereals, sodas and fruit drinks.
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Human beings have been on Earth for tens of thousands of years. In that time, our bodies got used to a certain diet. Then, in the last 100 years, our bodies have been exposed to much higher levels of fructose.
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Common sense might say that such a relatively sudden and large dietary change might be hard for the body to adjust to. Common sense isn’t always right, but in this case, it is: There is considerable evidence that today’s high levels of fructose are harmful.
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Virtually every cell in the body can break down glucose for energy. In contrast, about the only cells that can get energy directly from fructose are liver cells. What the liver does with fructose, especially when high levels enter it, has potentially dangerous consequences for our health.
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When fructose enters the liver, it goes through a series of changes. One remarkable change is that the liver uses fructose, a carbohydrate, to create fat.
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Give the liver enough fructose, and tiny fat droplets begin to accumulate in liver cells. This buildup is called non-alcoholic fatty liver disease. It looks like what happens in the livers of people who drink too much alcohol.
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The breakdown of fructose in the liver also:
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- elevates triglycerides;
- increases LDL (bad) cholesterol;
- promotes the buildup of fat around organs;
- increases blood pressure;
- makes tissues insulin-resistant, a precursor to diabetes.
- None of these changes are good for the arteries and the heart.
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There is considerable evidence that people who have more fructose in their diets have higher rates of non-alcoholic fatty liver disease, obesity, diabetes and heart disease. However, fructose has not been proven to be a cause of these conditions.
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Still, it’s worth cutting back on fructose. That’s what I tell my patients, and what I have done myself. But don’t do it by giving up fruit. Fruit is good for you, and it’s only a minor source of fructose for most people.
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Instead, cut back on refined sugar and high-fructose corn syrup. For starters, that means limiting your intake of sugar-sweetened drinks, pastries and breakfast cereals.