Enviromental factors

Although cancer is primarily considered to be genetically linked, it is now well established that diet has a significant effect on cancer incidence [4-6]. In fact, food consumption patterns could provide major insights into cancer risk and prevention despite the fact that their significance is not fully appreciated [7]. The changes in cancer incidence in migrant populations moving from low cancer incidence to high cancer incidence environments clearly demonstrate that environmental factors are more important than genetics [8,9].

Among the developed countries, Japan continues to exhibit the lowest cancer incidence in the major cancers types, including lung, breast and colon carcinomas, although some cancers have increased in incidence due to the introduction of Western dietary practices [10,11]. Notably, immigrant Japanese in California and Hawaii has a much higher incidence of breast and colon cancer [8,9]. In Japan, the consumption of fresh, raw foods continues to remain important even though in all other aspects (industrialization and urbanization) the Japanese have adapted the Western model. In addition, the Japanese have the same risk factors such as smoking, alcohol consumption and sedentary life styles as Westerners. The only notable exception in risk factors is the relative rarity of obesity in Japan, a difference that is also attributable to dietary customs.

Another line of evidence comes from Australia, demonstrating the increase in colon cancer mortality among immigrant populations originating from low-incidence countries [12]. Similar observations were made in some South Pacific Islander groups where the incidence of lung cancer is extremely low despite high rates of smoking [13]. Over the past decades, population-based approaches have identified food classes or nutrients that confer protection from various cancers or enhanced the risk of cancer [14-17]. In fact, there is evidence that dietary manipulations may be protective against 10–70% of all cancers, and may be as high as 50–70% against colon cancer [18,19].

Plant Phenolics

Epidemiological studies implicated high-saturated dietary fat and protein as a risk factor for colon cancer and established that high fiber, high fruit and vegetable content are protective [17,18]. The success of the dietary fiber hypothesis [20,21] is particularly intriguing in light of the recognition that the actual protective agent is not the fiber itself, but the cell wall components, phenolic polysaccharides and polyphenols [22-27]. The protective phenolic lignin and hemicellulose components are present in widely different concentrations in the cell walls of various plants and are released by bacterial enzymes in the human colon [23]. Such compounds have been isolated, e.g. from rice bran and green tea, and their cancer protective effects demonstrated [24,25,27]. Processed rice bran, however, had no such protective effect [28]. Many of these compounds have antioxidant, anti-mutagenic, anti-carcinogenic and anti-inflammatory effects that may be responsible for their anticancer effects [29].

A readily available source for such phenolic polysaccharides can be located in the nutritional and medical practices of the 19th and early 20th centuries [30,31]. Sugar cane molasses, a widely used nutrient, was served as a sweetener instead of purified sugar, stirred into milk and eaten instead of jam or jelly. It was also a popular medicinal agent:recent analyses demonstrated it to be a rich source of micro- and macronutrients [32]. Blackstrap molasses, its most concentrated form, was used for the therapy of a variety of diseases, including cancer [31]. Anecdotal evidence suggests that cancer was very rare among sugar cane plantation workers who were regularly consuming the raw brown sugar [33]. Blackstrap molasses is rich in a variety of essential minerals including iron, zinc, selenium, magnesium and potassium as well as the majority of the vitamin B complex [33], deficiencies of which confer a major cancer risk [34]. Molasses also contains high concentrations of amino acids and linoleic acid [35], an essential lipid that has a documented anti-tumor effect [36,37].

Cane molasses is fed widely to domestic animals [35]. A feeding study on the phenolic carbohydrate compounds of cane molasses suggested that they are beneficial to both ruminant and non-ruminant animals [38]. The feeding of 8% sugar cane bagasse to broiler chicken demonstrated weight gain and carcass quality as well as elevated immunoglobulin levels [39]. Recent data on cane molasses appear to lend support to historical accounts concerning its effectiveness as both preventative and a possible curative agent for some cancer.