Citrus Consumption and Risk of Cutaneous Malignant Melanoma

About consuming fruits; fresh, dried or juiced.
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RRM
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Re: Citrus Consumption and Risk of Cutaneous Malignant Melanoma

Post by RRM »

Not Ready For Prime Time
"the study population (health professionals paying pay more attention to unusual lesions) is not representative of the general population....
There is no other study in another population that has found this relationship between grapefruit or citrus consumption and the development of melanoma, and thus, there is little consistency in these findings....
There were no significant interactions between UV exposure and citrus consumption found in this study
"
And, "the strength of association is relatively small"
the association appeared to be stronger:
- among those with more blistering sunburns (particularly among those susceptible to sunbuirns)
- among obese individuals and those who exercised little.

So, if you take good care of your body, the association is weak.
Btw, a somewhat similar association is true for smoking; elevated intake of beta-carotene increases lungcancer risk in smokers.

Another comment about the quoted study:
"intermittent UV exposure, such as that obtained on weekends and holidays, was not associated with melanoma among this group. Instead, continuous exposure was associated, which is at odds with the current literature; continuous exposure does not demonstrate an increased risk for developing melanoma".
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Aytundra
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Re: Citrus Consumption and Risk of Cutaneous Malignant Melanoma

Post by Aytundra »

In my opinion
The title and conclusion of this article is poorly worded.
I think it should not say "Citrus" Consumption and Risk of ..., instead it should say they found "Grapefruit" Consumption and Risk of ...

From the article's abstract:
(Wu.S. et al., 2015) wrote:Among individual citrus products, grapefruit showed the most apparent association with risk of melanoma, which was independent of other lifestyle and dietary factors. The pooled multivariable hazard ratio for melanoma comparing the extreme consumption categories of grapefruit (≥ three times per week v never) was 1.41 (95% CI, 1.10 to 1.82; Ptrend < .001). "
In general, grapefruit is known to have compounds that interact negatively with many drugs and many chemicals; perhaps grapefruit consumers eat other things that interacted negatively with those compounds in grapefruit.

Saying Citrus increases risk of ... is a bit to broad.
Saying Grapefruit increases risk of ... is a bit closer to their data.

Reference of Article bbmine pointed out:
Wu. S. et al. (2015) Citrus Consumption and Risk of Cutaneous Malignant Melanoma. American Society of Clinical Oncology.http://jco.ascopubs.org/content/early/2 ... 8bff1e2eb1
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Re: Citrus Consumption and Risk of Cutaneous Malignant Melanoma

Post by Aytundra »

After reading the article: Berwick, M. (2015). Dietary Advice for Melanoma: Not Ready for Prime Time. American Society of Clinical Oncology. http://jco.ascopubs.org/content/early/2 ... .8116.full
Which critiques the previous article by Wu. S. et al. 2015.
Berwick, M. wrote:Second, there was a major inconsistency in that risk from the diet and the form of the citrus consumed were inconsistent; risk for grapefruit was from the whole fruit but not the juice, and risk from orange was from the juice but not the whole fruit. In explanation, the authors stated that psoralens and furocoumarins are present in higher levels in grapefruit than in grapefruit juice, and that the much more prevalent consumption of orange juice compared with oranges would counteract the lower levels of psoralens and furocoumarins in the juice.
I think Wu. S. et al., 2015, article's title should be:
Psoralens and furocoumarins consumption and the possible correlation to Cutaneous Melanoma, a limited investigation with oranges and grapefruit.
As, Berwick addresses that these are the main chemicals of focus in the study.

If I recall correctly from plant physiology:
Furocoumarins are found in vegetables; possibly greater amounts than an orange, not sure if a grapefruit is more than a vegetable. Which would give reasons why vegetables are not as good as fruits.
{furocoumarins, looks like a spelling error.}
A tundra where will we be without trees? Thannnks!
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Re: Citrus Consumption and Risk of Cutaneous Malignant Melanoma

Post by Aytundra »

Found the textbook that talked about furanocoumarins:
Taiz L. Zeiger E. (2010). Plant Physiology 5th edition. ISBN 978-087893-866-7. [i]Sinauer Associates, Inc.[/i] pg. 377 wrote: These compounds are not toxic until they are activated by light...Phototoxic furanocoumarins are especially abundant in members of Umbelliferae, including celery, parsnip, and parsley. In celery the concentration of these compounds can increase about one-hundredfold if the plant is stressed or diseased. Celery pickers, and even some grocery shoppers, have been known to develop skin rashes from handling stressed or diseased celery.


A PubMed search yielded the article on celery, furanocoumarins, and workers:
Berkeley, S.F. et al. (1986). Dermatitis in Grocery Workers Associated with High Natural Concentrations of Furanocoumarins in Celery. Annals of Internal Medicine.

It is interesting to note from the article, that furanocoumarins might be selected for during breeding of higher quality plants:
Berkeley, S.F. et al. (1986) wrote:The disease-resistant, high-quality brand of celery carried by these stores had higher levels of furanocoumarins, potent photosensitizers and a known cause of phytophotodermatitis, than other brands (p = 0.01). A randomly selected nationwide sample of stores in this chain showed dermatitis in 13 of 17 states and 26% of produce workers surveyed. Plant breeding to produce a more disease-resistant celery stock may lead to increased levels of endogenous furanocoumarins, resulting in phytophotodermatitis in grocery workers.
Which means that vegetables especially from the umbelliferae family should be considered in the diets of their subjects in their future research by those grapefruit writers above, before they start writing about citrus.
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