Eating apples appears to be linked to a reduced risk of cancer in various parts of the body.
The method applied in this research involved identifying relevant observational studies through a literature search of databases such as PubMed, Web of Science and Embase. Then, a random-effect model was utilized to estimate the cancer risk in different anatomical sites. Moreover, tests were conducted to assess between-study heterogeneity and publication bias.
In the discussion of results, forty-one studies were considered, including varied cancer types and sources. A significant reduction of lung cancer risk was observed in relation to high apple consumption in both case-control and cohort studies. However, in the cases of colorectal, breast, and overall digestive tract cancers, significant preventative effect of apples was only found in case-control studies, while prospective studies suggested no effect. There was no evidence of publication bias for colorectal, oral cavity, oesophageal and breast cancer, but the presence of some potential confounding effects related to consumption of other fruits has been recognized.
