Talk:Fructose

Fructose is a Hexose

Perhaps mention that fructose is considered a hexose sugar? 108.2.177.109 (talk) 05:39, 13 February 2011 (UTC)

Mention how fructose is synthesised?

Photosynthesis results in glucose and oxygen, but how do plants make fructose? 207.191.183.218 (talk) 22:17, 11 March 2011 (UTC)

Metabolic priority in regards to liver disease

Fructose#Liver disease: "When fructose reaches the liver," says Dr. William J. Whelan, a biochemist at the University of Miami School of Medicine, "the liver goes bananas and stops everything else to metabolize the fructose."

I have heard similar things said of alcohol. Is there any evidence that EVERYTHING is stopped to metabolize fructose? If there were free fructose and free alcohol, which would the liver prioritize, or perhaps it is able to do multiple jobs simultaneously? DB (talk) 19:05, 12 April 2011 (UTC)

Definition of "high/excess fructose consumption/intake/diet"

These phrases occur many times in the article but no actual indication is given of exactly what is meant. (I.e. exactly how much is "too much"?)
Does anyone know?
Thanks
-- TyrS  chatties  06:38, 15 April 2011 (UTC)

Composition of Corn Syrup =

In the table Carbohydrate content of commercial sweeteners (percent) the numbers in the corn syrup row don't add to 100%. What is the remaining 65% carbohydrate content? It would be great if somebody more informed than myself could verify whether this discrepancy is intentional.108.67.71.45 (talk) 06:07, 20 April 2011 (UTC)

I'm also convinced this is an error. Corn syrup's carbohydrate content should be glucose and perhaps maltose. See: http://www.ochef.com/362.htm but it needs a more official source. — Preceding unsigned comment added by 134.121.109.99 (talk) 20:35, 10 August 2011 (UTC)

Unsupported claim / non-sequitur

The article states:

Although all simple sugars have nearly identical chemical formulae, each has distinct chemical properties. This can be illustrated with pure fructose. A journal article reports that, "...fructose given alone increased the blood glucose almost as much as a similar amount of glucose (78% of the glucose-alone area)".

These statements have no apparent relation to one another. A more obvious example of distinct chemical properties would be differing solubility in water, not a random biological pheonomenon. Certainly biology is at its roots chemistry, but many steps removed and with various selective agents driving reaction preferences. Without additional context the example given does not illustrate the point at hand. --Belg4mit (talk) 14:36, 11 July 2011 (UTC)

Agreed, but I don't know how to fix that without deleting those 2 sentences. Dr. Morbius (talk) 20:04, 12 July 2011 (UTC)

Learning about sugars, I decided to look here to see what comments were posted. It is awkward. Stumbling upon this, I recommend either removing the second sentence completely, or separating the two sentences (into their appropriate paragraphs, but I have no suggestion where), or if you don't want to remove the second (less desirable because the second still does not support the first) you may consider something like this:

While all simple sugars have nearly identical chemical formulae, for the most part, each has quite distinct chemical properties. One [notable?] exception is illustrated with pure fructose: a journal article reports that, "...fructose given alone increased the blood glucose almost as much as a similar amount of glucose (78% of the glucose-alone area)".

However, I think I have read in other places (wiki) that say (or seem to say) that Fructose has an effect that differs from Sucrose - the combination of the Fructose and Glucose in the Sucrose being theorized as the contributing factor to the difference. The presence of the Glucose somehow moderating the Fructose's (different) effect. (not my field, so it's getting complicated for me)

However, the 'journal article' should be cited if the second sentence remains. Hope this helps & Regards -- Steve -- (talk) 17:11, 11 December 2011 (UTC)

I just want to also say that this paragraph is troubling. In fact it contradicts a paragraph a bit later that says GI of fructose is 19 vs. 100 for glucose. GI = glycemic index = effect on blood glucose. How can it be 78% and 19%? It also contradicts info on metabolism of fructose which happens mostly in the liver whereas glucose just passes into the bloodstream. From my reading I think the 78% is not trustworthy. I have seen more references to fructose not having a significant impact on blood glucose and insulin. It could be just that the 78% study was with diabetic patients only. At any rate, it needs to be called out somehow. Sorry I'm not expert enough to have a better suggestion... 74.3.100.30 (talk) 00:28, 6 November 2012 (UTC) JPL

Fructolysis

I corrected some errors in the fructolysis section (previously claimed that initial metabolism produces fructose-1,6-biphosphate) and added a link to the fructolysis page. I think large sections here are redundant with the fructolysis page and could be scrapped. Also, the further metabolic processes discussed (glycogen and triglyceride synthesis) are not intimately related to fructose, and are described on separate pages, and should probably be removed. Rollowicz (talk) 09:29, 30 July 2011 (UTC)

Out of topic info in intro

This seems out of place to me: "Sucrose is a disaccharide with a molecule of glucose and a molecule of fructose bonded together with a glycosidic linkage. Most modern fruits and vegetables have been bred to have much higher sugar content than the wild plants they are descended from." — Preceding unsigned comment added by 18.189.112.118 (talk) 02:45, 19 October 2011 (UTC)

I agree, and I deleted both sentances. Kduckworth (talk) 05:56, 5 February 2012 (UTC)kate

Figure 1 is incorrect

The beta D fructose in Figure 1 is incorrect. See http://sv.wikipedia.org/wiki/Fruktos for the correct image. — Preceding unsigned comment added by Htreadup (talk • contribs) 12:57, 27 October 2011 (UTC)

The image used as Figure 1 (File:Fructose-isomers.jpg) does not have anything labeled "beta D fructose". Can you be more specific about which image is your concern? -- Ed (Edgar181) 13:04, 27 October 2011 (UTC)

Increased fructose associates with elevated blood pressure. -- PMID 20595676

Jalal DI, Smits G, Johnson RJ, Chonchol M.

Increased fructose associates with elevated blood pressure.

J Am Soc Nephrol. 2010 Sep;21(9):1543-9. Epub 2010 Jul 1.

PMID 20595676

PMCID: PMC3013529

Free PMC Article

http://jasn.asnjournals.org/cgi/pmidlookup?view=long&pmid=20595676

http://www.ncbi.nlm.nih.gov/pmc/articles/pmid/20595676/?tool=pubmed

Abstract

The recent increase in fructose consumption in industrialized nations mirrors the rise in the prevalence of hypertension, but epidemiologic studies have inconsistently linked these observations. We investigated whether increased fructose intake from added sugars associates with an increased risk for higher BP levels in US adults without a history of hypertension. We conducted a cross-sectional analysis using the data collected from the National Health and Nutrition Examination Survey (NHANES 2003 to 2006) involving 4528 adults without a history of hypertension. Median fructose intake was 74 g/d, corresponding to 2.5 sugary soft drinks each day. After adjustment for demographics; comorbidities; physical activity; total kilocalorie intake; and dietary confounders such as total carbohydrate, alcohol, salt, and vitamin C intake, an increased fructose intake of > or =74 g/d independently and significantly associated with higher odds of elevated BP levels: It led to a 26, 30, and 77% higher risk for BP cutoffs of > or =135/85, > or =140/90, and > or =160/100 mmHg, respectively. These results suggest that high fructose intake, in the form of added sugar, independently associates with higher BP levels among US adults without a history of hypertension. Comment in

PMID 20595676

PMCID: PMC3013529

Free PMC Article

http://jasn.asnjournals.org/cgi/pmidlookup?view=long&pmid=20595676

http://www.ncbi.nlm.nih.gov/pmc/articles/pmid/20595676/?tool=pubmed

99.190.133.143 (talk) 23:05, 1 November 2011 (UTC)

Increased fructose associates with elevated blood pressure. -- PMID 20595676

Jalal DI, Smits G, Johnson RJ, Chonchol M.

Increased fructose associates with elevated blood pressure.

J Am Soc Nephrol. 2010 Sep;21(9):1543-9. Epub 2010 Jul 1.

PMID 20595676

PMCID: PMC3013529

Free PMC Article

http://jasn.asnjournals.org/cgi/pmidlookup?view=long&pmid=20595676

http://www.ncbi.nlm.nih.gov/pmc/articles/pmid/20595676/?tool=pubmed

Abstract

The recent increase in fructose consumption in industrialized nations mirrors the rise in the prevalence of hypertension, but epidemiologic studies have inconsistently linked these observations. We investigated whether increased fructose intake from added sugars associates with an increased risk for higher BP levels in US adults without a history of hypertension. We conducted a cross-sectional analysis using the data collected from the National Health and Nutrition Examination Survey (NHANES 2003 to 2006) involving 4528 adults without a history of hypertension. Median fructose intake was 74 g/d, corresponding to 2.5 sugary soft drinks each day. After adjustment for demographics; comorbidities; physical activity; total kilocalorie intake; and dietary confounders such as total carbohydrate, alcohol, salt, and vitamin C intake, an increased fructose intake of > or =74 g/d independently and significantly associated with higher odds of elevated BP levels: It led to a 26, 30, and 77% higher risk for BP cutoffs of > or =135/85, > or =140/90, and > or =160/100 mmHg, respectively. These results suggest that high fructose intake, in the form of added sugar, independently associates with higher BP levels among US adults without a history of hypertension. Comment in

PMID 20595676

PMCID: PMC3013529

Free PMC Article

http://jasn.asnjournals.org/cgi/pmidlookup?view=long&pmid=20595676

http://www.ncbi.nlm.nih.gov/pmc/articles/pmid/20595676/?tool=pubmed — Preceding unsigned comment added by 99.190.133.143 (talk) 23:12, 1 November 2011 (UTC)

Gout citation

"Gout" section: Today I added a citation for the non-cited mention of a "recent" British Medical Journal article linking fructose consumption with incidence of gout. By searching online, I found a 2008 BMJ study that fits nicely with the assertion made; then re-wrote the sentence to express more precisely the conclusion of this study, but I cannot say for certain whether I located the same study that the author of that sentence had in mind. Reverence Still (talk) 00:25, 5 December 2011 (UTC)

Health Effects Re Diabetics

The descriptions of effects of fructose upon diabetics, addressed briefly within a few different sub-sections of the "Health Effects" section, seem to have been written by multiple people of differing views. Which of course they were. Would a knowledgeable person please helpfully review and re-write these sub-sections to be more clear and consistent on the topic of fructose's effect on diabetics? Reverence Still (talk) 00:43, 5 December 2011 (UTC)

Compared to sucrose

The claim that sucrose and high fructose corn syrup have similar physiological effects seems to be overstating the conclusion cited in the subsequent sentences. Melanson et. al found that HFCS and sucrose are similar in the short term but "Longer-term studies on connections between HFCS, potential mechanisms, and body weight have not been conducted". Hence, the statement in this section must have a smaller scope (i.e. the short term physiological effects of HFCS and sucrose appear to be similar. However, long term studies have yet to be conducted). — Preceding unsigned comment added by Austin.momii (talk • contribs) 01:50, 10 January 2012 (UTC)

Dispute over claims made in a reference

If a claim is made in the article and it's backed up by a reference and you don't like the claim then you need to find another reference that disputes the original reference. If you disagree with the reference you need to find something that contradicts it. Your opinion would not be a valid claim to contradict the reference. If you have a dispute with the authors of a study WP is not the place to hash out your disagreement. The claims made in the following paragraph are backed up by the reference:

• Fructose is a reducing sugar, as are all monosaccharides. The spontaneous chemical reaction of simple sugar molecules binding to proteins, known as glycation, is thought to be a significant cause of damage in diabetics. Fructose appears to be equivalent to glucose in this regard and so does not seem to be a better answer for diabetes for this reason alone, save for the smaller quantities required to achieve equivalent sweetness in some foods.

Adding things to the claim that are not in the reference simply because you don't agree with the results of the study used in the reference is inappropriate. Find a study that contradicts what's in the paragraph but don't edit the paragraph by adding irrelevant claims. The reference that is used makes no mention of rats being used as test subjects therefore adding the claim that the effects described in the article were observed in rats is irrelevant. If you have another study that makes the same claim using a rat model then add it to the article but don't change the original claim in the paragraph. Dr. Morbius (talk) 19:55, 28 March 2012 (UTC)

Title of the Levi and Werman study already used in the paragraph before my edits is: Long-Term Fructose Consumption Accelerates Glycation and Several Age-Related Variables in Male Rats.[1] Quoting from the paper, Discussion paragraph 4: This study demonstrates that long-term fructose feeding accelerates aging as expressed by changes in various age-related markers measured in collagen from skin and bones.

Making interpretation about any fructose effect on human metabolism or skin/bone health is simply conjecture, so must be stated as such for the common lay reader of this article. The tone of this paragraph is that fructose consumption is linked to diabetes, which, by scientific evaluation, is preposterous and only preliminarily tested.

The McPherson article was correctly cited as evidence for the potential -- but not proven -- effect on proteins, as that study was only an in vitro analysis of such effects, so is also preliminary and unsubstantiated for any interpretation about diabetes.

I suggest you re-read the paragraph and its references, and, if still confused, submit the issue for dispute resolution.--Zefr (talk) 23:38, 28 March 2012 (UTC)

The original edits that you did did not use that reference. The original claim that was there that used the Werman reference was about senescence not about glycation. You then edited the claim that was about glycation and misrepresented that it was about rats while using the Mcpherson reference. Dr. Morbius (talk) 19:01, 29 March 2012 (UTC)

Fructans

Under Food Sources it states.... "Fructose exists in foods either as a free monosaccharide or bound to glucose as sucrose, a disaccharide"

What about when it exists as a fructan? According to Wikipedia a Fructan is is "a polymer of fructose molecules".

"Fructans with a short chain length are known as fructooligosaccharides, whereas longer chain fructans are termed inulins. Fructans occur in foods such as agave, artichokes, asparagus, leeks, garlic, onions (including spring onions), yacon, jícama, and wheat.

http://en.wikipedia.org/wiki/Fructan http://en.wikipedia.org/wiki/Fructooligosaccharide

CompassKT (talk) 18:48, 26 October 2012 (UTC)

Oranges

I'd be interested in seeing oranges or orange juice in the list. In fact, I think a juices list would be very useful. -Reticuli 65.29.194.159 (talk) 17:18, 31 March 2013 (UTC)