An article published in JAMA Network Open confirms that existing dietary guidance regarding increasing consumption of dietary fibre and dairy products and limited intake of red meat and alcoholic beverages is associated with a lower risk of colorectal cancer (CRC).
The analysis included 45 meta-analyses describing 109 associations of dietary patterns, specific foods, food groups, beverages (including alcohol), macronutrients, and micronutrients with the incidence of CRC. The researchers graded the evidence of association as being convincing, highly suggestive, suggestive, weak, or not significant.
The results show that higher red meat intake and heavy alcohol intake were associated with an increased risk of CRC, while higher dietary fibre, calcium, and yoghurt intake reduced the risk of CRC.
The researchers also found suggestive evidence for an association of a healthy dietary pattern, Mediterranean diet, pesco-vegetarian diet, and semi-vegetarian diet, intake of whole grains, total dairy products, and supplemental calcium with lower CRC incidence. No convincing evidence was found to support limiting consumption of processed meat for CRC prevention.
The findings of this study support existing recommendations for diet in the primary prevention of CRC, but more research is needed on specific foods for which evidence remains suggestive, the authors conclude.