Cancer, a leading cause of mortality worldwide, is a complex disease influenced by various genetic, environmental, and lifestyle factors. Among these, diet and nutrition play a significant role in both cancer prevention and progression.
Research has shown that certain dietary patterns and specific nutrients can either increase or decrease the risk of developing different types of cancer. Understanding the intricate relationship between what we eat and cancer development is crucial for making informed dietary choices that promote long-term health and well-being.
Diet and Cancer
In a recent study published in Cancer Screening and Prevention, researchers reviewed current knowledge on the beneficial and detrimental effects of dietary patterns and nutritional supplements on cancer risk.
A major modifiable risk factor for cancer, beyond lifestyle choices, is diet. A growing body of research highlights the dual role of diet in both preventing and causing cancer.
Unhealthy diets high in calorie-dense foods, sugar-sweetened beverages, processed and red meats, and saturated and trans-fats are linked to an increased risk of obesity, metabolic disorders, and various cancers. Cancer-related deaths due to obesity are 14% among men and 20% among women. Additionally, the consumption of alcohol and processed meats is associated with cancers of the liver, pancreas, esophagus, and colorectal cancer.
Conversely, healthy dietary patterns that emphasize whole foods, fruits, vegetables, and grains are associated with a reduced cancer risk. Dietary phytochemicals have also shown promise in chemoprevention by exhibiting properties that suppress carcinogenesis and alter metastatic molecular pathways.
In the present review, researchers discussed the beneficial and detrimental roles of diet and nutritional supplements in cancer risk.
Can Certain Food Cause Cancer?
A substantial body of evidence supports a causal link between diet and cancer. However, the intricate mechanisms of cancer development have made it challenging to find direct correlations between specific dietary factors and cancer risk.
Epidemiological studies indicate that the consumption of certain foods is strongly associated with an elevated risk of some cancers. Factors such as timing, quantity, and duration of exposure affect cellular responses, complicating the identification of individual dietary components linked to cancer risk. Consequently, recent cancer prevention guidelines have adopted a holistic approach, emphasizing dietary patterns over individual foods. Healthy eating patterns are associated with lower risks of colon and breast cancers.
Although the evidence linking red and processed meats to gastrointestinal cancer is not conclusive, processed meats (such as cured, salted, smoked, or fermented meats) and red meats (such as beef) are believed to increase cancer risk. Research on the connection between various foods and cancer risk is limited, yet many studies report an increased risk of liver and esophageal cancers due to alcohol consumption.
Based on current research, the World Cancer Research Fund recommends a diet rich in vegetables, fruits, and whole, unprocessed foods to reduce cancer risk and overall mortality. Additionally, dietary pattern modifications are being explored as potential cancer treatment methods. For instance, ketogenic diets, which are high in fat and low in carbohydrates, are being investigated for their ability to target cancer cell metabolism and improve prognosis.
Dietary Supplements in Cancer Prevention
The review also explored the impact of various nutritional components and supplements on cancer. Dietary fats include mono- and polyunsaturated, as well as saturated fatty acids. Polyunsaturated fatty acids, such as omega-3, are credited with anti-cancer properties. Omega-3 fatty acids, primarily found in marine fish and in smaller quantities in plants like flaxseed, include docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). These fatty acids possess anti-inflammatory properties, and studies indicate that they could reduce colorectal cancer risk by 24%.
Clinical trials have linked EPA supplementation with reductions in adenomatous polyps, but further research is needed to fully understand the effects and optimal dosages of fatty acid supplementation.
The review also examined the roles of micronutrients such as selenium, folate, vitamins D, C, A, and E, calcium, and magnesium in cancer. Folate shows a dose-dependent relationship with cancer, where specific levels have beneficial effects, but high doses can be carcinogenic. Vitamins C, A, D, and E, along with selenium, have demonstrated antioxidant properties that might be protective against cancer, though excessive supplementation could be harmful.
Studies on mineral supplements and cancer risk suggest that while a balanced intake of micronutrients might be beneficial, excess supplementation can be detrimental.
Additionally, the review discussed the role of polyphenols in cancer prevention. Polyphenols like curcumin and resveratrol are linked to antioxidant and anti-inflammatory effects. Curcumin, in particular, has been studied for its potential in cell cycle arrest and apoptosis, making it a candidate for cancer treatment.
Key Takeaway
Changes in lifestyle and eating habits have made people more prone to diet-related illnesses and cancers. However, it is well-known that dietary changes can significantly reduce the risk of these illnesses. Following a healthy and balanced diet can lower the risk of cancer. A diet high in fruits and vegetables is especially protective against cancer, likely due to polyphenols and other beneficial compounds.
It’s important to note that simply avoiding certain foods won’t lower cancer risk, and no single diet or food group can do this alone. However, eating a nutrient-rich diet that includes fruits, whole grains, legumes, and vegetables can help reduce the risk of cancer and other chronic diseases. Antioxidants found in fruits, vegetables, and nuts play a key role by repairing cells, reducing inflammation, and minimizing the formation of free radicals, which can lead to cancer.
Research from various studies help understand the link between diet and cancer prevention, but there is still a lot to learn about this relationship. Dietary supplements should be used cautiously, as they can have both positive and negative effects, and research shows mixed results.
Cancer research is complex, and it’s difficult to determine the exact impact of diet alone because many lifestyle factors influence cancer risk. Therefore, no single dietary plan has been proven to reduce cancer risk conclusively. However, overall dietary improvements can have a positive effect on cancer prevention. It’s also important to avoid excessive use of dietary supplements, as they can be harmful.