Exploring the Effects of a High Chlorophyll Dietary Intervention to Reduce Colon Cancer Risk in Adults

Study Summary

Colon cancer is the third most common cancer in men and women and over 70% of cases are preventable. A western diet, characterized by low vegetable and high red and processed meat intake, indisputably increases colon cancer risk. Heme, which gives red meat its color, is highly reactive, induces hyperproliferation and promotes DNA damage in the colon to a greater degree than any other red meat-associated carcinogen. Preclinical models indicate dietary chlorophyll, which gives green leafy vegetables their color, binds and stabilizes heme in the lumen, preventing genotoxicity. Additionally, data from our randomized controlled weight loss trial indicate increasing red meat consumption has deleterious effects on the gut microbiome, which is also implicated in colon cancer etiology. Because heme-containing foods are the richest sources of bioavailable iron and several other vitamins and minerals, mitigating their potential risks may be more beneficial than eliminating meat, poultry, fish and seafood in their entirety from the diet for risk reduction. This feasibility study will begin to explore the research question: Will adding chlorophyll-rich green leafy vegetables to the diet prevent the deleterious effects of heme-rich red meat on the human host and microbiome? The investigators will randomly assign 50 adults at increased risk of colorectal adenoma to a block randomized crossover study with two 4-week dietary regimens in which: 1) participants will be provided with frozen green leafy vegetables and counseled to consume a high chlorophyll diet including 1 cup per day of cooked green leafy vegetables and normal meat (high heme) consumption; or 2) continue their normal high heme, low chlorophyll diet (control). A 4-week washout period encouraging habitual diet will be employed between the intervention periods and data will be collected at all four time points. This study is critical in translating preclinical findings and has the potential to open the door to new know

Primary Outcome

Accrue 50 participants

Interventions

• BEHAVIORAL High chlorophyll diet - intervention 1st
• BEHAVIORAL High chlorophyll diet - control 1st