Food Habits, Lifestyle Factors, and Risk of Prostate Cancer in Central Argentina: A Case Control Study Involving Self-Motivated Health Behavior Modifications after Diagnosis

Cancer is the second most important non-communicable disease worldwide and disproportionately impacts low- to middle-income countries. Diet in combination with other lifestyle habits seems to modify the risk for some cancers but little is known about South Americans. Food habits of Argentinean men pre- and post-diagnosis of prostate cancer (n = 326) were assessed along with other lifestyle factors. We studied whether any of the behaviors and risk factors for prostate cancer were found in men with other cancers (n = 394), compared with control subjects (n = 629). Before diagnosis, both cases reported a greater mean consumption of meats and fats and lower intakes of fruits, green vegetables, cruciferous vegetables, legumes, nuts, seeds, and whole grains than the controls (all p < 0.001). After diagnosis, cases significantly reduced the intake of meats and fats, and reported other dietary modifications with increased consumption of fish, fruits (including red fruits in prostate cancer), cruciferous vegetables, legumes, nuts, and black tea (all p < 0.001). Additional lifestyle aspects significantly predominant in cases included a reduced quality of sleep, emotional stress, low physical activity, tobacco smoking, alcohol consumption, living in rural areas, and being exposed to environmental contaminants. Argentinian men were predisposed to modify their unhealthy dietary habits and other lifestyle factors after cancer diagnosis.


Introduction
Global prevalence of non-communicable diseases (NCDs) is one of the main concerns of health professionals worldwide. According to the World Health Organization (WHO), cardiovascular diseases, prostate cancer (n = 326) or other cancer (n = 394) (primarily lung and colorectal cancer). Men of a similar age and residing in the same province as the cases and who did not receive a cancer diagnosis were invited to participate as controls (n = 629) after their medical visit. One hundred seventy-nine participants in each group was calculated as the minimum sample size required to measure a medium effect size with a 90% power at α = 0.05.
The study protocol was reviewed and approved by the Research Review Board (registered under the #42.2011) and Ethics Committee of the River Plate Adventist University (resolution #2-2012-05.1/2012), and includes patient consent after proper explanation of the study.
A structured questionnaire was used for targeting potential protectors and main lifestyle related-risk factors for NCDs, especially those associated with male cancers [22][23][24]. The questionnaire had two main sections with questions on: (1) sociodemographics and general health information; (2) food habits and lifestyle-related factors.

Sociodemographics and Health Information
Participants provided information on age (years), education (elementary/secondary school, postsecondary and university), actual marital status (singled, married, widowed, and divorced), main labor activity (rural, industrial, commercial, autonomous professional, and other), and life residency (city or rural with less than 2500 people grouped, as characterized in Argentina). Body Mass Index (BMI, kg/m 2 ) was calculated from reported weight and height. Data collected also included the initial reason for seeking medical assistance that finally led to a cancer diagnosis (regular health check-up or presence of a given symptom), family history of cancer (any type of cancer in relatives, including grandfather/grandmother and participant's siblings), and history of a medical diagnosis of prostatitis, urinary tract infections, arterial hypertension, diabetes, thyroid dysfunction, depressive disorder, and correlated medications. We also inquired about life-disturbing events and important emotional stressors in the last years prior to cancer diagnosis, such as those related to divorce, breakup of a significant relationship, serious illness or death in close family members, loss of a long-time job, and other personal issues that negatively impacted life experiences.

Food Habits and Lifestyle-Related Factors
Questions in this section were divided in two parts concerning present (controls and cases) and past practices and life experiences before cancer diagnosis (cases). We clarified, firstly, that participants should answer the questions based on their most common and typical habit that best represents their lifestyle, whether in the preceding years before cancer detection or current behaviors. Regarding diet, men were asked about their regular consumption of common foods and food groups usually found in Argentinean local markets: meat, fish, milk and milk products, fruit (pears, apples, peaches, grapes, bananas, oranges, mandarins, lemons, etc.), red fruits (strawberries, cherries, tomatoes, watermelons, red grapefruit), green salads (lettuce varieties, arugula, escarole, spinach, watercress, etc.), cruciferous vegetables (cabbage, broccoli, cauliflower), legumes (lentils, black beans, garbanzos, peas, soy), seeds (sunflower, chia, flax, sesame, etc.), nuts (walnuts, almonds, peanuts, etc.), whole grain cereals (oats, wheat, rice, etc.), sugary foods including sweet beverages and confectionary, foods with high contents of trans and saturated fats including fries, factura (a kind of croissant regularly eaten in Argentina), and fatty desserts, coffee, black tea, and mate. For these items, examiners specified an approximate regular portion of each element using a non-quantitative food frequency questionnaire (FFQ), and participants reported the habitual frequency using the following categories: (1) never; (2) 1-2 times/week; (3) 3-4 times/week; (4) 5-7 times/week. Participants also reported the usual water consumption (cups per day).
For other lifestyle factors, participants were asked about: physical activity (30 min or more of moderate aerobic activity at least 3 or more times/week on a regular basis); sleep pattern and usual evening sleep duration in hours (6 or fewer, between 6 and 8, and more than 8), sleep interruptions (more than two times per night), difficulty sleeping and the use of medications for sleeping; tobacco use (present, past, and passive history of smoking); and alcohol consumption (daily, occasional, or never). Participants were also asked about their contact with agricultural chemicals (indirect exposure for those living in areas less than 1000 m of fumigation zones and direct exposure for those who handle, apply, or sell agrochemicals) [25], time of exposure (years), identification of substances by commercial or chemical names (grouped according to class of pesticides), and personal protective garments while using agrochemicals [26]; and general exposure, to compounds possibly associated with prostate cancer such as cadmium, metallic dust, and liquid fuel combustion [27].
We also applied a descriptive analysis considering seven unhealthy habits, combining five food habits with two other lifestyle-related factors, in order to determine their accumulation pattern in cases and controls. The following factors were considered risk behaviors: intake of fresh fruits, red fruits, and green salads was <3 times/week, for each group of food [28]; the intake of meats and fatty foods was three or more times/week, for each group of food [3]; physical activity was <3 times/week; and current tobacco smoking [7].

Statistical Analyses
Descriptive analyses were carried out for sociodemographic and health information, and food habits and lifestyle-related factors for cases and controls. Chi-square Itest was used for assessing differences in categorical variables among participants of the three groups. McNemar's test was applied for examining the significance of the differences between pre-and post-diagnosis habits for individual variables inside each group, with reference to prostate cancer cases and other cases separately. In order to calculate odds ratios (ORs) and 95% confidence intervals we used multiple logistic regression models, adjusted for age, level of education, marital status, BMI, and family history of cancer. For that we compared dietary habits, place of residency (urban or rural), physical activity (three or more times a week), history of important emotional distress, and use of statins. For tobacco smoking we considered the categories active, passive, or past smoking. SPSS Inc., (Chicago, IL, USA) version 17 software was used for statistical analyses. P values < 0.05 were considered statistically significant.

Results
Men in both cancer cases had, on average, a small but significantly higher age than controls, lower body mass index (BMI) and, particularly for men in the prostate cancer group, a lower level of education. Prostate cancer was detected mainly during medical checkups, while the majority of men with other types of cancer only looked for a physician after the onset of symptoms. In both cases the overall history of cancers in the family, considering near or distant relatives, was greater than controls. Medical history of prostatitis and arterial hypertension was more common in men with prostate cancer while other cancer cases also showed a higher prevalence of arterial hypertension than controls. The use of statins was more prevalent in controls. A major stressor and emotionally life-disturbing event was more prevalent in cases than in controls (Table 1). Although the majority of the studied population was not directly exposed to agrochemicals, cases showed greater exposure, both direct and indirect contact, than the control subjects. Cancer cases had a substantially higher contact with organophosphorus compounds than controls in addition to a more frequent history of inadequate protective measures. Housing in a rural area, defined as fewer than 2500 people, was more prevalent in cases than controls (Table 1). Regarding diet and food habits, before diagnosis, cases reported a greater mean consumption of meat, fat, and coffee than the controls. They also ate significantly less fruit, vegetables, green salads, cruciferous vegetables, nuts, seeds, and whole grains (Table 2). Conversely, after cancer diagnosis, men significantly reduced the intake of meat, fat, and coffee and reported other diet modifications with increased consumption of fish, fruit, including red fruits (only in prostate cancer cases), cruciferous vegetables, legumes, nuts, and black tea. Similar consumption of sweet beverages, mate, and fish were found before cancer diagnosis in all groups including controls. Daily water intake was significantly lower in prostate cancer cases compared to the remaining participants (Table 2).
Before diagnosis both cases had an overall reduced quality of sleep than controls with a higher consumption of sleep medications, more sleep disruptions, and difficulty falling asleep. After cancer diagnosis these trends were maintained, with a further reduction in hours of night sleeping and an increased use of sleep medications among cases compared with controls (Table 3). Cases were significantly less engaged in regular physical activity than the controls, with reduced activity after diagnosis. Previous to cancer diagnosis, cases consumed more alcohol and used more tobacco than controls. This behavior changed significantly after diagnosis. Tobacco use was more prevalent in men with other types of cancer than in men with prostate cancer. The use of antidepressant medications was similar in all groups but its consumption increased significantly after diagnosis of cancer in both cases (Table 3).
Living in an urban area, participating in physical activities, and eating fruit and vegetables, including red fruits, green salads, and cruciferous vegetables, three or more times a week was inversely associated with a risk of prostate cancer. The same association was observed for the other cancer cases regarding the intakes of fruit, cruciferous vegetables, whole grains, and dairy, and living in an urban area. While the intake of coffee was associated only with prostate cancer risk, the higher intake of foods rich in fat, meat, and black tea was associated with risk of developing prostate cancer and other cancers. Familial history of cancer and a significant life stressor were also associated with risk in both cases. In this study, the usage of tobacco was associated with a risk for other cancers but not for prostate cancer (Table 4).    An integrative analysis of seven risky health behaviors (low intake of fresh fruit, red fruits, and green salads; high intake of meat and fatty foods; insufficient physical activity; and tobacco usage) revealed a directly proportional association between the number of risk factors accumulated and the presence of a cancer diagnosis. Before diagnosis, both cancer groups had a higher number of risky health behaviors with 78.1% of the prostate cancer cases and 80.5% of the other cancer cases accumulating in their lifestyle 4-6 risky behaviors, whereas 83.4% of the control subjects accumulating 1-4 risky factors. After cancer diagnosis, cases changed their behaviors and prostate cancer cases moved towards the distribution pattern found in fewer risk factors (Table 5). The seven risk behaviors considered were: intake of fresh fruits <3 times/week; intake of red fruits <3 times/week; intake of green salad <3 times/week; intake of meats ě3 times/week; intake of fatty foods ě3 times/week; physical activity <3 times/week; current tobacco smoking. * p < 0.001 ** p = 0.001 for χ 2 test.

Discussion
In this study, cancer cases in both groups presented with a substantially higher number of risk factors related to lower levels of education, familial history of cancer, prostatitis (in prostate cancer cases), and unhealthy lifestyle habits associated with diet, physical activity, sleep, tobacco smoking, alcohol consumption, emotional distress, and exposure to agrochemicals, than the control subjects. After cancer diagnosis, a significant number of cases reported favorable changes in regard to diet, tobacco and alcohol consumption, which may interfere with disease progression and benefit quality of life if these healthier behaviors are sustained. These findings add to the growing literature suggesting that unhealthy lifestyle behaviors may be important factors influencing cancer development. Among all the participants of this study, prostate cancer cases had the lower educational level, which may be associated with unhealthy choices [29]. However, most of the prostate cancer diagnoses were initiated during medical check-ups, which suggests a positive impact of public health campaigns for prostate cancer screening. Similarly, Bekker-Grob et al. (2013) found that men from the southwest of the Netherlands with lower educational levels decided more easily on a prostate cancer screening [30]. In contrast with the diagnosis of prostate cancer, the majority of men with other cancers only searched for medical aid after onset of symptoms. As suggested by the study of Okada et al. (2016) in Chile, early detection approaches and cancer prevention policies in South America should be reconsidered, especially for the most prevalent cancers in men such as colorectal and lung cancer [31]. According to the National Association for Cancer Registry in Argentina (2011), prostate, lung, colorectal, stomach, and bladder cancers are among the highest prevalent cancers in Argentinean men [32].
The increased risk of cancer in first generations from relatives with prostate cancer has been extensively studied but the latest investigations showed a larger effect including second and third degree relatives influencing risk of prostate cancer, with equivalent risks from history of prostate cancer from the paternal and maternal sides [33]. Segregation analysis indicates that prostate cancer resembles adult-onset family cancer syndromes with the participation of several genes [34]. Pakkanen et al. (2007) showed that Mendelian recessive inheritance is also associated with prostate cancer and paternal regressive coefficient values, influenced by lifestyle choices and environmental factors, modulates prostate cancer risk [35]. A recent study found that prostate cancer was 25 times higher among members of a large Familial Ovarian Cancer Registry [36], highly suggestive of an effect of non-prostate cancers history on prostate cancer risk. With respect to the broad approach we have used for ascertaining history of cancer, inquiring about any type of cancer in close or distant relatives is useful, since we detected a significantly higher familial prevalence of cancer in both cases compared with controls. Nevertheless, these findings warrant further studies since our data were limited. Besides inherited genetic susceptibilities, progenitors may influence their descendants through socialization and impart lifestyle preferences and inclinations, predisposing food choices, physical activity practices, alcohol usage, and tobacco smoking [37][38][39]. Furthermore, regulation of DNA expression through epigenetic mechanisms is influenced by the environment and dietary habits of progenitors and has been suggested to be associated with metabolic syndrome, neurodegenerative diseases, and cancers in their descendants [40,41]. Recent findings propose that lifestyle habits can exert influences in family environments since spouses of long-lived families also enjoy relatively healthy lives [42]. Thus, health intervention strategies to make families aware of the scope of their influence on healthy lifestyle behaviors are required [43].
Prostatitis has been associated with an elevated risk for prostate cancer [44] and loss of tumor suppressor genes in prostate tissues [45]. Interesting, 15% of prostate cancer cases in our study had a history of prostatitis, exceeding the usual prevalence (2.2%-9.7%) [46] and also the prevalence we found in the other cancer cases (3.8%) and controls (10%). Among participants of our study, prostate cancer cases consumed significantly less water. Chronic prostatitis was recently shown to be higher in individuals with low water intake [47]. Very few studies have considered beverage habits around the world, particularly water intake in patients diagnosed with cancer. Therefore, it would be interesting to corroborate and extend our initial observations in further investigations.
When asked about a major life-disturbing event, both cases presented a more prevalent history of emotional distress than controls. Li et al. (2014) found a greater prostate cancer risk in men who experienced important emotional distress [48]. Although there are many attempts trying to link emotions such as worry, anger, fear, anxiety, and depressive feelings with the etiology of malignant tumors, it has been difficult to demonstrate specific biological causal links. Nevertheless, studies have shown that altered emotions and psychological distress caused by persistent life-troubling situations may affect several aspects of the lifestyle such as reducing the hours of rest and sleep [49], modifying diet preferences favoring higher intakes of palatable foods rich in fat and sugar [50], prompting social isolation and intensifying alcohol and tobacco consumption [51], and reducing physical activity levels [52]. All of these lifestyle factors have been shown to affect cancer risk and mortality. Perceived emotional stress and lack of social support, in a study with 4015 Swedish men, accounted for a 66% increased risk of prostate cancer mortality [53]. Thus, comprehensive psychosocial care will assist oncological patients in making healthy lifestyle decisions. Integration of public and private health initiatives for addressing this need is recommended [54].
Suboptimal diet has been shown to influence carcinogenesis and it is one of the most studied lifestyle-related factors associated with NCDs [3,55,56]. The World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) have been regularly examining new evidence for the impact of diet on cancer and, while tremendous advances have been made [57], it continues to be an area under intense investigation. Epidemiological studies have attempted to specify certain foods that may prevent or favor cancer development but it is challenging to translate this information into the clinical scenario [58]. In this study, we focused on the certain groups of foods frequently mentioned in the NCDs literature, including those targeted at cancer prevention strategies such as fruit, red fruits, legumes, green salads, cruciferous vegetables, and nuts [55,59]. Although the data collection does not thoroughly discriminate all types of foods and precise quantities, it may be useful for assisting clinicians, urologists, oncologists, and other professionals in making health recommendations. The value of nutrition education has been highlighted by other studies in which most of the patients and their partners requested from different health professionals dietary information soon after a prostate cancer diagnosis [21,60,61]. Indeed, the results obtained by using our non-quantitative FFQ were able to find differences between food consumption among cases and controls revealing distinct habits and preferences among these groups. Showing similarity to a "Western diet" pattern [9], cases of our study consumed more fats and meats, and lower intakes of plant foods than controls. Selenium, folate, vitamin C, D, E, K, phytosterols, resveratrol, and other health-promoting phytochemicals are found mainly in a plant-based diet. These substances have been associated with lower incidences of several cancers [62]. These and other nutritional compounds may exert anti-tumor activities, inhibiting proinflammatory transcription factors such as NF-KB, diminishing arachidonic acid, inflammatory prostaglandins, angiogenesis, oxidative stress, and potentially chemo-and radio-sensitizing tumor cells [3,63]. Enterolignans are produced by the gut microbiome after intake of dietary fiber and have been suggested to exert important biological functions, preventing chronic diseases such as cancers [64,65]. Similarly, a Mediterranean-style diet or a vegetarian diet characterized by good quantities of fruit, vegetables, complex carbohydrates, healthy fats, and moderate amounts of proteins may help prevent cancer development/progression [16,66,67]. We observed that a diagnosis of cancer prompted many men of our study to make self-motivated positive dietary changes, increasing the intakes of fruit and vegetables and decreasing fat and foods from animal sources. Avery et al. (2013) found that one third of men diagnosed with prostate cancer spontaneously adopted a healthier diet [20], while in another study about one half improved their diet [68]. The adoption of a healthy lifestyle after a cancer diagnosis has been associated with a better quality of life and superior clinical outcomes [9,69]. Intakes of healthy diets reduce biomarkers of oxidative stress in men diagnosed with prostate cancer [70]. Higher mortality after prostate cancer diagnosis was associated with low intake of vegetables and high intake of saturated fats in the recent Physicians' Health Study (PHS) [71]. Also, the European Prospective Investigation into Cancer and Nutrition (EPIC) study reported a lower risk of some cancers in 47,479 Italians following a Mediterranean diet rich in raw vegetables, fruit, and olive oil [66].
Growing evidence for the adoption of a healthier lifestyle for patients diagnosed with cancer has being fostered by recent studies and the integration of these concepts into oncological care is novel. Research in this area is warranted, particularly in Latin America and the Caribbean, where very few studies have been done and cancer deaths are projected to double from 2012 to 2030 [72]. This is important given the traditional Argentinean diet, high in red meat, saturated fats, and simple carbohydrates and low in vegetables, all of which increase the risk of prostate cancer [73]. We also found that consumption of coffee and black tea was significantly more prevalent in cases than in controls and logistic regression analysis showed a risk associated with these beverages. After cancer diagnosis, both cases decreased coffee intake but increased black tea consumption. Recent epidemiological studies on coffee did not find an association with a prostate cancer risk [74,75] and some inversely associated coffee intake with prostate cancer risk [76]. However, green tea has been largely associated with higher antioxidant capacity, and a recent clinical trial with prostate cancer patients did find benefits from green tea on several biomarkers but did not show any benefit to black tea consumption [77].
Adequate sleep seems to be crucial for biological regeneration through the activation of cell repair mechanisms mainly by the action of melatonin, which participates in the regulation of hormones, fatty acids metabolism, energy expenditures via insulin/IGF-1, and adult stem cells differentiation/proliferation [78,79]. Investigations indicate that disruption of the circadian rhythm is associated with impaired immunity, activation of pro-inflammatory cytokines [80,81], and cancer development [82,83]. Nevertheless, only a few studies have examined the impact of sleep on prostate cancer and other cancers in men, with some suggesting a causal link [84][85][86] but others suggesting no link [87,88]. A recent prospective study found that men who self-reported sleep problems had significantly lower melatonin levels in urinary samples and this group presented a four-fold increased risk of developing advanced prostate cancer [13]. Shiftwork has been implicated with prostate cancer risk and a strong positive association with Prostatic Specific Antigen (PSA) levels was found [89]. In our study, while we did not find a risk associated with insufficient sleep, there was a statistically significant difference in the descriptive analysis, showing worst sleep parameters in both cancer groups, but more prominently in prostate cancer cases. These changes in sleep alterations could be corroborated, at least in part, by the substantial high use of sleeping medications among men before prostate cancer diagnosis (31.6%) and in men with other cancers (23.6%), in regard to control subjects (15.1%). Petrov et al. (2014) found that 9.6% of their subjects used prescribed sleep medications and 11.1% used over-the-counter sleep aids [90]. Analogous to other investigations, where cancer patients presented sleep disturbances after cancer diagnosis and treatment [91], both cancer groups of our study significantly increased the consumption of sleep medications (up to 44.7% of men with other cancers) and antidepressants (up to three times more than at baseline), possibly associated with cancer-related fatigue and depression cluster conditions [92]. However, management of sleep and depression includes also non-pharmacological approaches. Men diagnosed with or at risk of cancer might benefit from health interventions designed for improving quality of sleep and depression mitigation as shown, for instance, with cognitive brain therapy [93].
Being physically active is an important aspect of a healthy lifestyle and while the benefits for the cardiovascular system have been extensively demonstrated, it is an emerging area of interest in prevention of cancers [94,95]. In the preceding years before diagnosis, most of the cases in our study were not engaged in regular physical activity (PA) and PA levels were even lower after cancer diagnosis. Friedenreich et al. (2016) asked men with prostate cancer diagnosis about their lifetime history of PA and found a direct association for those performing more PA, including recreational activity and non-sedentary occupational activity, with a lower risk of prostate cancer death [12]. In our study we found that three or more times a week of PA was associated with prostate cancer risk reduction. In the clinical setting, however, it is challenging to establish specific recommendations of PA for cancer patients due to a variety of personal conditions and oncologic treatments. Nevertheless, sedentary behaviors should be discouraged, since a growing body of research associates sitting time with all-cause mortality [96], including mortality for some cancers [97,98]. The American Cancer Society recommends 150 min of moderate or 75 min of vigorous PA per week for cancer risk reduction [99]. Just half an hour of daily walking, considered a low-intensity PA, was associated with reduced liver cancer mortality [100], and modest amounts of weekly vigorous PA for 3 h (playing tennis, biking, or swimming) seemed to decrease prostate cancer specific mortality [101] and improved quality of life in prostate cancer patients [102].
Tobacco is recognized as the major preventable risk factor for most cancers [103], contributing to one in three cancers [104]. Tobacco has been associated with lung, oral cavity, pharynx, larynx, esophagus, stomach, liver, urinary tract, cervix, and other cancers [105]. However, the association of tobacco with a prostate cancer risk is not so clear [106]. While in our study the habit of smoking was significantly more prevalent in both cancer groups than in controls, we did not find an increased risk of prostate cancer associated with smoking. Most epidemiological investigations have not found a prostate cancer risk associated with smoking [107,108], while some others did find an association [109]. However, post-diagnosis tobacco exposure is adversely associated with prostate cancer prognosis. Recent studies show greater expression of immune/inflammatory genes in prostate tumor tissues [110] and higher biochemical disease recurrence, metastasis, and mortality in prostate cancer patients who smoke [111][112][113]. In our study, about 15% of men with prostate cancer spontaneously quitted smoking after diagnosis, while 40% of men with other cancers quit, a significant reduction in both cases. Hence, men facing a cancer diagnosis might be susceptible to lifestyle changes, creating an opportunity for a "teachable moment" [114]. Since in our study there was an important difference among cases regarding smoking reduction, we can also consider that the etiology of prostate cancer is not stereotyped with tobacco as might be the case with other cancers.
Along with smoking, alcohol consumption has been an even more controversial subject in the etiology of prostate cancer but not with many other types of cancers [115]. Most research has not found a direct effect of alcohol on prostate cancer development; however, some studies found an increased risk of prostate cancer considering lifetime alcohol consumption [116], and prostate cancer aggressiveness [117]. In our study, both cases were significantly more involved in overall alcohol intake than controls but logistic regression analysis did not show any associated risk. Nevertheless, alcohol consumption may be associated with co-occurring unhealthy habits, constituting an unidentified confounding feature of epidemiological studies. Hansel et al. (2015) demonstrated that wine consumers favored purchasing healthy foods while beer consumers were more likely to buy unhealthy foods [118]. In our study, more than half of men from both cases substantially reduced their everyday consumption of alcohol following diagnosis. Little research has assessed alcohol intake after prostate cancer diagnosis. Hackshaw-McGeagh et al. (2015) reported positive changes with reduction of alcohol intake in approximately one quarter of men diagnosed with prostate cancer [119]. It would be important, therefore, to investigate alcohol effects following prostate cancer diagnosis and its association with concomitant food habits.
Additional factors may be connected with cancers in men such as those resulting from occupational and environmental exposures [120]. Argentina is among the three largest producers of soy, corn, and other crops [121]. Prostate cancer has been found to be associated with the use of some herbicides [122], organophosphate, and organochlorine insecticides [120,123]. However, none of these associations appear to be conclusive. In our study, there was not a significant risk for prostate cancer as well as other cancers associated with pesticide exposures, but we cannot rule out the possibility since prolonged specific type and time, direct and indirect, pesticide exposures were more prevalent in cases than in controls. Also, more than half of the cases directly exposed to pesticides did not use adequate protective measures for handling pesticides, suggesting higher vulnerability to contaminants. We also found a lower risk of prostate cancer and other cancers in men living in urban areas (not necessarily large cities), in contrast with those living in rural areas. However, this may be associated with health services accessibility, larger variety of foods, water treatment, and probably less agrochemical exposures among other factors [124]. Studies show that although the predicted risk of cardiovascular diseases seems to be lower in rural than in urban areas [125], geographic cancer distribution and prevalence is still a matter of investigation. Díaz et al. (2010) showed a higher prevalence of colorectal cancer in rural than in urban areas of Córdoba, Argentina [126]. Sharp et al. (2014), studying 20 types of cancers in Ireland, found that 12 of them were prevalent in urban areas [127]. However rural-urban area gradients are difficult to establish in Argentina since important socioeconomic diversity exists in both areas, and urban residence is not necessarily provided with better housing conditions, nutritional status, or health insurance availability [128].
Altogether, risky lifestyle behaviors were more prevalent in cases than in control subjects. This is corroborated by the combined analysis of seven lifestyle-related factors, which reveals a higher level of modifiable risky health behaviors in cases. Control subjects possessed about half of the unhealthy behaviors present in cases before diagnosis.

Conclusions
Our research provides data on Argentinean men that support recent trends worldwide on the potential influence of extrinsic risk factors on cancer, with insights into food habits and other lifestyle-related factors that may impact on the promotion of health or disease. To our knowledge, this is one of the first studies in South America concomitantly exploring food habits with several lifestyle-related factors of men with a cancer diagnosis. It was remarkable to observe the predisposition to positive changes in Argentinean men in the face of a cancer diagnosis, especially those associated with dietary aspects. This may be particularly linked with sociocultural characteristics of Latin Americans and further studies are warranted. Even though our study has a number of limitations, innate to observational approaches, it raises several questions and opens an avenue for future research, fostering investigations on cancer risk in men and providing cancer prevention strategies in South America.