Anti-Cancer Effects Of Vegetables: A Questionnaire Based Study

by

Saad Asad1                                     BDS, FCPS

Mahrukh Tanveer2                      BDS

Amna Asif3                                        BDS

 

BACKGROUND: One of the major causes of death throughout the world remains the cancer. Though research have shown the importance of diet and physical activity in preventing cancers and awareness programs have been introduced and reported but still studies available on awareness programs regarding anti-cancer impact of vegetables are limited. Aim of this study is thus to assess the base line knowledge of Dental Graduates about the anti-cancer vegetables with the aim that their knowledge will have an impact on the awareness of the community. METHODOLOGY: The study was conducted through a 10 instrument questionnaire on a sample consisted of Sixty Four Dental Graduates (24 males and 40 females) from University College of Dentistry, The University of Lahore.

RESULTS: Awareness regarding different vegetables that can have anticancer effect was assessed through the questionnaire. Baseline knowledge of Dental graduates about anticancer effect of vegetables was limited and only 7-11% of the Dental Graduates were actually aware of the antitumorigenic effect of different vegetables. CONCLUSION: This study concludes that base line knowledge of dental graduates about anti-cancer effects of vegetables was poor.

KEYWORDS: Anti-cancer vegetables, cancer, cancer awareness program.

HOW TO CITE: Asad S, Tanveer M, Asif A. Anti-cancer effects of vegetables: a questionnaire based study. J Pak Dent Assoc 2015; 24(4):204-209.

Received: 10 December 2015, Accepted: 20 December 2015

INTRODUCTION

One of the major cause of death throughout the world remains the cancer1,2.Carcinogenesis is a multifactorial phenomenon with a complex interplay between genetics and environmental factors; mainly related to healthy habits and lifestyle2,4. Cancer may also be caused by oxidative stress in addition to these factors5,6.In the recent past though exponential progress in the prevention and management of cancers have taken place but as mentioned already its incidence is increasing at an alarming rate day by day due to the reasons already mentioned7,8. However, over a quarter of the incidence may be preventable by just adjusting the diet7. Diet in the recent past has been given too much importance because of its anti-oxidant and anti-cancer effects. “Let food be thy medicine and medicine be thy food”, as said by the father of medicine, Hippocrates in 431 B.C. Nature has provided us with a variety of treatment modalities in the form of fruits and vegetables9. Many of them consist of ingredients with hidden pharmaceutical qualities ranging from anti-inflammatory to anti-carcinogenic agent. They not only boost our innate immunity but also act as an adjunct to medicines for specific treatment9.

In a review of 200 papers on anti-cancer effect of vegetables Block et. al. reported that a significant proportion of studies found a positive relationship10. In another review of 206 studies, the similar relationship was examined and it was found that cruciform vegetable reduces chances of cancer occurrence11. Amjad Al et al in their study found an anti oxidant to anti-cancer effect of Sulforaphane (SFN) a metabolic by product of cruciferous vegetables12. Awasthi S, Saraswathi NT in found a potent anticancer effect of glucosinolate found in cruciferous vegetables13. Ahmadi A, Shadboorestan A in their study found that flavonoids one of the most important ingredients in vegetables and fruits exhibits an anti-cancer effect14. Michaud DS et al in their study found that 20% increase in vegetable intake generally corresponds to a 20% decrease in cancer rates, and a 20% increase in cruciferous vegetable intake corresponds to a 40% decrease in cancer rates15. Cohen JH et al in another study found that 28 servings of vegetables per week decreases prostate cancer risk by 33%, moreover just 3 servings of cruciferous vegetables per week decreased prostate cancer risk by 41%16. It is worth mentioning here that cruciform vegetables includes: Bok Choy, Broccoli, Broccolini, Cabbage, Cauliflower, Mustard green, raddish and turnip etc17.

Though research have shown the importance of diet and physical activity in preventing cancers and awareness programs have been introduced and reported but still studies available on awareness programs regarding anticancer impact of vegetables are limited.Yong-chuan Wang et al in their study found that strategies for cancer prevention and control implemented in the USA can be valuable models for China18. The same can be over extended for other countries.Ken Yamaguchireported cancer prevention programs in Japan19. These can be valuable modes for cancer control.Fotedar V et al in their study concluded that though the mean knowledge of the population about cancers is good but the knowledge and practices about risk factors had to be reinforced20. Altin C et al in their study concluded that limited cancer literacy instruments are available21. Aim of this study is thus to assess the base line knowledge of Dental Graduates about the anti-cancer vegetables with the aim that their knowledge will have an impact on the awareness of the community.

METHODOLOGY

The study was conducted through a 10 instrument questionnaire on a sample consisted of Sixty Four Dental Graduates (24 males and 40 females) from University College of Dentistry, The University of Lahore. After obtaining informed consent they were given a questionnaire. Questionnaire comprised of 10 instruments each testing different vegetables that might have an impact as anti-cancer diet. Data was then analyzed using SPSS 16.0 and frequency and percentage for each instrument for each subject was then calculated.

Questionnaire

Q1 Do you know that diet has an impact in preventing cancers?

Q2. What do you think whether Broccoli has any anticarcinogenic effect?

Q3. What do you think whether Brussels Sprout has any anti-carcinogenic effect?

Q4. What do you think whether Cabbage has any anticarcinogenic effect?

Q5. What do you think whether Cauliflower has any anti-carcinogenic effect?

Q6. What do you think whether Raddish has any anticarcinogenic effect?

Q7. What do you think whether Turnip has any anticarcinogenic effect?

Q8. What do you think whether Spanich has any anticarcinogenic effect?

Q9. What do you think whether Tomato has any anticarcinogenic effect?

Q10. Do you think that this questioner has improved your awareness regarding anti-cancer Vegetables?

RESULTS

Dental Graduates perspective regarding anti-cancer vegetables has been discussed in table 1.

Table 1: Frequency and Percentage of each question used to assess the role of different vegetables as anti-carcinogenic agents.

DISCUSSION

The quality and quantity of diet has direct impact on systemic health22. Considering these effects, our questionnaire comprised of 10 instruments related to anti-cancer vegetables especially cruciform vegetables was presented to each subject and base line knowledge of dental graduates regarding anti-cancer vegetables was assessed. First question was related to the fact that whether they have any idea about the role of diet in preventing cancers; 81% of the dental graduates were aware of this fact in our study.

Amjad Al et al in their study found an anti oxidant to anti-cancer effect of Sulforaphane (SFN) a metabolic by product of cruciferous vegetables especially found in Broccoli12. Qazi et al in another study found that a natural product Sulforaphane (SFN) with antioxidant properties from broccoli has great potential to be used in chemoprevention23. John D. Clarke, Roderick H. Dashwood, Emily Ho in their study found that Isothiocyanates (Sulforaphane) found in cruciferous vegetables such as broccoli and Brussels sprouts may lower overall cancer risk, including colon and prostate cancer24. Y Zhang et al in another study have supported the anti-carcinogenic effect ingredients found in Broccoli25. Campas-Baypoli, O.N et al in another study found potent anticancer effect of Sulforaphane (SFN) a by product of Broccoli26. Matsui, T et al in their study also found that Sulforaphane (SFN) exhibit a potent anticancer effect especially in osteosarcomas27. Unfortunately only 9.37% of the Dental Graduates in this study were aware of well known anti-cancer effect of Broccoli.

Brussels sprouts, kale, broccoli and various cabbages were found to possess very potent anti-cancer activities as observed in both epidemiological and laboratory studies28-32. de Figueiredo SM et al in their study established that Sulforaphane (SFN)  a phytochemical commonly found in cruciferous vegetables such as broccoli, brussels sprouts and cabbages exhibits anticancer effect33. Unfortunately only 10.94% of the Dental Graduates in this study were aware of well known anticancer effect of Brussels Sprouts.

Cabbage has been reported to possess anti-oxidant and anti-inflammatory effects which may have preventive role in chronic disorders34. Fresh cabbage juice, prepared either separately or mixed with other vegetables such as carrot and celery, is often included in many commercial weight-loss diets, diets that improve the bioavailable content of nonheme iron, as well as alternative therapies for cancer patients35-37. Renuka DJ , Berla TE in another study found that Sulforaphane (SFN) an isothiocyanate formed by hydrolysis of glucosinolates found in Brassica oleraceae possess anticancer and antioxidant activities38. Unfortunately only 12.5% of the Dental Graduates in this study were aware of well known anti-cancer effect of Cabbage.

A lower cancer incidence has been linked with consumption of cauliflower and cruciform vegetables39. Interestingly, PEITC is an anti-cancer compound found in vegetables and was first reported in 201440. Unfortunately only 9.37% of the Dental Graduates in this study were aware of well known anti-cancer effect of Cabbage.

O’Hare T.J. et al in their study found that radish sprouts have potentially greater chemoprotective action against carcinogens than broccoli sprouts41.Gutiérrez RMP and Perez RL in their study found that aqueous extract of the salted Radish roots showed antimutagenic activity against Salmonella typhimurium TA98 and TA10042. O’Hare T.J. et al in their study found that Daikon and radish sprouts contain high levels of glucoraphenin, a glucosinolate which hydrolyses to form sulphoraphene which is a potent inducer of phase 2 detoxification enzymes and consequently has potential anti-cancer action43. Flavonoids, polyphenolic acids, and other phenolic compounds found in radish exhibit potent anticancer effects44. Unfortunately only 7.81% of the Dental Graduates in this study were aware of well known anticancer effect of Raddish.

Turnip exhibit anti-tumorigenic activity due to Indoles found in it44,45. Robin, Saroj Arora and Adarsh Pal Vig in another study indicated the presence of strong antimutagenic factors and hydroxyl radical scavengers in Turnip seeds46. Unfortunately only 7.81% of the Dental Graduates in this study were aware of well known anticancer effect of Turnip.

Recently, a case-control study of dietary factors and gastric cancer in Korean patients reported that high consumption of food rich in nitrate, including cooked spinach, increases the risk of gastric cancer47,48. In our study 9.37% of the Dental Graduates were aware of anticancer effect of Spanich.

Flavonoids also found in tomato have been demonstrated to inhibit carcinogenesis in vitro and substantial evidence indicates that they can also do so in vivo49-51. Chick WDW et al in their study found that tomato leaves extract significantly contains purified active fractions with anti-cancer properties52. Bhuvaneswari V and Nagini S in their study found that lycopene found in tomat exhibits an array of biological effects including cardioprotective, anti-inflammatory, antimutagenic and anticarcinogenic activities53. Rao AV and Agarwal S.Dietary intakes of tomatoes and tomato products containing lycopene have been associated with decreased risk of chronic diseases such as cancer and cardiovascular diseases54. Scolastici C et al in a study found that in addition to its antioxidant properties, lycopene shows an array of biological effects including antimutagenic and anticarcinogenic activities55. In our study only 10.94% of the Dental Graduates were aware of anti-cancer effect of Tomato.

In last 89% of dental graduates believed that this questionnaire has improved their base line knowledge about anti-cancer diet. These types of surveys and awareness camps should be conducted at regular intervals to improve the base line knowledge of health professionals and community.

CONCLUSION

This study concludes that base line knowledge about anti-cancer vegetables needs improvement. This may help in changing the dietary habits and thus may help in reducer the increasing incidence of cancers.

Authors’ contributions:

SA Conceived, designed, analyzed and wrote the manuscript, MT contributed in data collection and data analysis, AS contributed in data collection and data analysis.

Disclosure: There is no potential conflict of interest

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  1. Associate Professor, Head Department of Orthodontics and Oral Biology & Tooth Morphology, University College of Dentistry, The University of Lahore.
  2. Ex-House Surgeon, University College of Dentistry, The University of Lahore.

Corresponding author: “Dr. Saad Asad ” < saad2609@yahoo.com >