**1. Introduction**

Currently, there are more than 12 million new cancer cases each year worldwide, and it constitutes approximately 12% in mortality statistics. The cancer incidence remains high in south East Asia. In recent years, an alarming increase in cancer incidence has been observed in parts of central and Eastern Europe. A number of studies have implicated chronic inflamma‐ tions as of the factors involved in cancer development, but the specific ways chronic inflamma‐ tion lead to cancer is not very clear at the moment. It has been estimated that almost 20% of all cancers are associated with chronic inflammation. Many cancers arise from sites of infection, chronic irritation and inflammation. Tumor necrosis factor (TNF alpha) is a pleiotropic cytokine, is known to regulate multiple inflammatory cells (neutrophils and macrophages). The assump‐ tion that nutrition is an important factor in the risk of cancer development dates back to ancient times. Wiseman in 1676 suggested that cancer might arise from "an error in diet" and he recommended restriction of salt and meat in the diet as a means of cancer prevention [1]. During the early decades of twentieth century, the idea of diet modification in cancer prevention gained momentum and several recommendations for the increase or decrease of various dietary components have been tried. Shah in 1907 advocated a prudent dietary regime designed to reduce the risk of cancer development, with more food of vegetable origin, less meat, alcohol and tobacco [2].Along with the scientific advances during the early part of the 20th century, two hypotheses on the environmental cause of cancer were developed. The first one related to occupational exposure of workers to chemical carcinogens and the other one focused on various dietary components. Hoffman in 1931 indicated that increased amounts of fats in diets, sugar and bread as possible contributing factors to some types of cancer development [3]. At the same time, a few epidemiological surveys indicated that a number of dietary components may contribute to the pathogenesis of cancer [4,5]. During the last 50 years, increased attention was focused on the preventive and modifying actions of diet on cancer prevention in general. An early analysis of cancer incidence worldwide indicated that over 50% of cancers is due to external factors and hence theoretically preventable [6-10, 18]. This was further reinforced by a large

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number of descriptive, ecological and epidemiological studies. Studies by Doll and Peto indicated the importance of antioxidants, leafy vegetables, fish and several other bioactive micronutrients in cancer prevention [7].In 1982, The National Academy of Sciences in USA proposed six interim guidelines to reduce the risk of cancer [8]. This included reduction of dietary fat, increased consumption of food rich in fruits and vegetables, salt restriction, decreased intake of smoked food-stuffs and reduced intake of alcohol. This review will discuss some important concepts in cancer prevention by diet modification.

**Rank cancer site New cases %of all cancers** 1 Lung 1608 12.7 2 Breast 1384 10.9 3 Colorectal 1235 09.8 4 Stomach 989 7.8 5 Prostate 899 7.1 6 Liver 750 5.9 7 cervix uteri 530 4.2 8 Esophagus 482 3.8 9 Bladder 383 3.0 10 Non-Hodgkin lymphoma 356 2.8 11 Leukemia 350 2.0 12 Corpus uteri 288 2.3 13 Pancreas 279 2.2 14 Kidney 274 2.4 15 Others 1879 13.8

Dietary Aspects in Cancer Prevention — A Mini-Review

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As can be observed, lung cancer is the most common cancer worldwide contributing to nearly 13% of the total number of cases diagnosed in 2008. Breast cancer in women is the second common cause of cancer followed by colorectal cancer. The number of lung cancer in man has decreased a little from 18.6% in 1996 to 16.5% in 2008 [20].The global cancer burden doubled in the last three decades of the twentieth century and it is estimated that it will triple by 2030. The major increase would be in low and medium resource countries in Asia, Africa and Latin America. At the same time, there is a clear message of hope that some of the cancers can be prevented with advances in sophisticated technology combined with genetic and other

Like many other chronic diseases, the major underlying causes of cancers are environmental in nature. Apart from genetic factors, food and nutrition are important modifiers of cancer risk..Studies of immigrants in various parts of the world support the concept that many human cancers arise from interaction between the environment and constituents of the cells and their membranes. In the past, the concept of etiology of cancer has generally focused on four agents: viruses, radiation, chemical carcinogens and environmental pollutants. Currently, it is estimated that environmental factors are primarily responsible for a significant percent of all

**Table 2.** Cancer statistics. Cases diagnosed in 2008 (100s). Both sexes

screening techniques.

**3. Diet and carcinogenesis**
