Fermentation creates new species, some of which can be carcinogens. I was specifically looking at nitrosamines, which probably cause gi tract cancers. Which is disappointing, because fish sauce makes everything taste good. [1]
This may be behind the high gastric cancer rates in parts of asia.
This can also occur in vegetables [2] [3]
This full text has a list of possible sources, in fermented and unfermented foods both http://www.ncbi.nlm....les/PMC2786176/
preserved meats and fish seem to be the worst.
This is a review study of nitr* foods and cancer. Mostly preserved & smoked meat & fish, and preserved vegetables. The have some of beer, but i think the levels were greatly reduced by changes in malting procedure."Nitrosamine and related food intake and gastric and
oesophageal cancer risk: A systematic review of the
epidemiological evidence"
free fulltext: http://www.wjgnet.co...327/12/4296.pdf
Here is a list of nitr* in foods "Development of estimates of dietary nitrates, nitrites, and
nitrosamines for use with the short willet food frequency
questionnaire
"
free fulltext: http://www.biomedcen...5-2891-8-16.pdf
there were some studies showing ascorbic acid and garlic reducing formation/carcer.
I would minimise in general, other than specific foods which have been well studies, like cocoa, wine, yoghurt, etc.
here's a fun list of possible toxins http://www.ncbi.nlm....les/PMC2782753/
STUDY 1
Levels of direct-acting mutagens, total N-Nitroso compounds in nitrosated fermented fish products, consumed in a high-risk area for gastric cancer in southern China
2003.
Abstract
A high gastric cancer mortality in Fujian province (Peoples Republic of China) has been associated with the consumption of certain salted fermented fish products such as fish sauce (FS). We have investigated the levels and nature of N-nitroso compounds (NOC) and genotoxins present, before and after nitrosation, in 49 FS samples collected from villages in this high-risk area, pooled into six samples. The concentrations of total NOC before nitrosation ranged from 0.2 to 16 μmoles/1, and after nitrosation at pH 2 and pH 7, they rose by up to 4800- and 100-fold, respectively. In nitrosated samples, 40–50% of total NOC was not extractable into organic solvents; volatile N nitrosamines accounted for 1–2% and N-nitrosamino acids for 8–16% of total NOC.
None of the FS samples exhibited genotoxic activity, but after nitrosation all were weakly active in the SOS chromotest. The highest SOS-inducing potency was observed with nitrosated ethyl acetate extracts of most samples. The formation of methylating agents was measured by incubation of nitrosated FS with DNA and subsequent analysis of 7-methylguanine adduct. 2 of the 6 nitrosated FS samples caused a slight increase in DNA methylation. 1 pooled home-made FS sample (the only one tested) contained tumour promoter-like substances, as measured by expression of certain EBV genes in Raji cells.
HPLC fractionation of ethyl acetate extracts of FS samples allowed identification of three UV-absorbing peaks that, upon nitrosation, produced direct-acting genotoxins. This genotoxicity was partly ascribed to the formation of nitrite-derived arene diazonium cations that were characterized by a coupling reaction with N-ethyl-1-naphthylamine and thin-layer chromatography.
The presence of nitrite-dependent genotoxins and tumour promoter-like substances supports the hypothesis that FS consumption is a risk factor for gastric cancer in certain areas of China.
STUDY 2
etables, but not pickled vegetables, are negatively associated with the risk of breast cancer.
Abstract
This study investigated the association between pickled vegetable consumption and the risk of breast cancer using a validated food frequency questionnaire. A total of 358 patients with breast cancer who were matched to 360 healthy controls by age (using a 5-yr age distribution) were recruited from the National Cancer Center in South Korea. After adjusting for nondietary risk factors, total vegetable intake was inversely associated with risk of breast cancer. However, unlike nonpickled vegetables, pickled vegetable intake and its proportion relative to total vegetables were positively associated with the risk of breast cancer, and this association was more profound and consistent when pickled vegetable intake was considered as a proportion relative to total vegetables (odds ratio [OR] = 6.24, 95% confidence interval [CI] = 3.55-10.97; P for trend <0.001 for highest vs. lowest quartiles of intake) than as the absolute consumed amount (OR = 2.47, 95% CI = 1.45-4.21; P for trend = 0.015 for highest vs. lowest quartiles of intake). These results suggest that not only the amount of total vegetable intake but also the amounts of different types of vegetable (i.e., pickled or nonpickled) and their proportions relative to total vegetables are significantly associated with the risk of breast cancer.
PMID: 20432165 [PubMed - indexed for MEDLINE]
STUDY 3
Pickled vegetables in the aetiology of oesophageal cancer in Hong Kong Chinese
Abstract
Oesophageal cancer is common in Chinese populations, but individual-based epidemiological studies have provided little explanation. A case control study with 400 cases and 1598 controls (800 hospital and 798 general practice) was conducted among Hong Kong Chinese. In multivariate analyses, statistically significant effects on risk were detected for several potentially preventable exposures with high attributable risks (ARs). These included preference for consuming drinks or soups at high temperature (AR=14%), infrequent consumption of green leafy vegetables (AR=15%) and citrus fruits (AR=26%), ingestion of pickled vegetables (AR = 29%), tobacco smoking (AR=44%), and alcohol drinking (AR=48%). On the assumption of multiplicative risk, the combined AR due to these exposures was 89%. This is the first case control study to show an association between pickled vegetable consumption and oesophageal cancer risk. The finding considerably strengthens the evidence for carcinogenicity of N-nitroso compounds in man and helps to explain the very high risk among Chinese.
