Cancer is the leading cause of morbidity and mortality worldwide, and the
number of new cases is expected to rise. Among all the risk factors for cancers, lifestyle,
eating habit and obesity are considered the most significant determining factors.
In this chapter, we review evidence indicating that diet and obesity play significant
roles in both the initiation and promotion of the cancer development. Furthermore, we
also critically summarize how cancers can be prevented or its growth be inhibited by
dietary modulation and reducing obesity. The evidence reviewed here overwhelmingly
suggests that nutritional recommendations for cancer prevention should focus on
improving host immunity. Specifically, this means consuming diets high in omega-3
polyunsaturated fatty acids (PUFAs) in a low omega-6 to omega-3 ratio, and rich in
fiber and anti-angiogenic compounds such as omega-3 PUFAs, antioxidants and
polyphenols. Given the causal link between obesity and cancer, reduced obesity, for
instance, by dietary modulation may help to reduce cancer risk. Nevertheless, the
conventional studies of the anti-cancer and/ or anti-obesity effects of dietary
components or compounds may be complicated by the influences from background
diet, life style, gut microbiome, age, environmental factors, genetic factors, drug
therapy, and an individual’s physical and pathological conditions. Therefore, in order
to have the most effective dietary modulation for an individual for cancer prevention
and treatment, “personalized nutrition” may be an alternative approach. Facing the
challenge of how to optimize the individual’s nutrition, we believe “omic” technologies
and system biology will have great potential for designing “personalized nutrition” that
can prevent the onset and slow down, if not reverse, the progression of the cancer.
Keywords: Cancer, Carcinogen, Dietary component, Epidemiology, Genomics,
Lipidomics, Metabolomics, Obesity, Oncogenic signaling pathway, Proteomics.
