Harvard Expert Identifies Foods Linked to Increased Cancer Risk

In a recent social media post, Dr. Saurabh Sethi, a gastroenterologist affiliated with Harvard University and trained at AIIMS and Stanford, highlighted several common foods that may elevate cancer risk. His findings, shared on June 9, 2025, emphasize the importance of dietary choices in mitigating health risks associated with cancer.

Dr. Sethi points out that while no single food can directly cause cancer, certain dietary habits can significantly increase the likelihood of developing the disease. His list of the most concerning foods includes ultra-processed meats, sugary drinks, deep-fried foods, charred meats, alcohol, and ultra-processed snacks. Each of these categories has been linked to various forms of cancer through scientific research.

The World Health Organization (WHO) categorizes processed meats—such as sausages, hot dogs, and deli meats—as Group 1 carcinogens, a classification shared with tobacco products. This classification stems from extensive studies indicating that the preservatives and additives, particularly nitrates and nitrites, present in these foods contribute to cancer risk (World Health Organization, 2020).

Sugary drinks, according to Dr. Sethi, are particularly concerning due to their ability to spike insulin levels, leading to weight gain and increased inflammation—both recognized factors in cancer progression. A study published in the American Journal of Clinical Nutrition (2021) supports this claim, demonstrating a direct correlation between sugary beverage consumption and obesity, which is a significant cancer risk factor.

Similarly, deep-fried foods pose a risk due to the harmful compounds produced during cooking at high temperatures, such as acrylamide and trans fats. Research published in the Journal of Food Science (2022) indicates that these substances can exacerbate inflammation and oxidative stress in the body, both of which are linked to higher cancer rates.

Charred meats, which often contain carcinogenic compounds due to high-temperature cooking methods, are also on Dr. Sethi’s warning list. According to the National Cancer Institute (2023), the cooking of meats over open flames can produce heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs), which have been shown to damage DNA and potentially induce mutations that lead to cancer.

Alcohol consumption, even in moderate amounts, has been linked to an increased risk of various cancers, including breast, liver, and colorectal cancers. Dr. Sethi notes that alcohol can disrupt hormone levels, particularly estrogen, and produce acetaldehyde, a toxic byproduct that can damage DNA (American Society of Clinical Oncology, 2022).

Furthermore, ultra-processed foods such as packaged snacks and ready-to-eat meals often contain high levels of refined carbohydrates and added sugars, driving systemic inflammation—a precursor to many chronic illnesses, including cancer (Harvard T.H. Chan School of Public Health, 2023).

As Dr. Sethi emphasizes, reducing or eliminating these foods can significantly contribute to long-term health and may lower the risk of developing cancer. This perspective aligns with a growing body of research advocating for healthier dietary practices as a means of cancer prevention.

In conclusion, while the link between diet and cancer risk is complex, understanding the role of specific foods can empower individuals to make informed choices that potentially enhance their health outcomes. As the conversation around diet and cancer continues to evolve, health professionals stress the importance of balanced nutrition and the avoidance of high-risk foods in daily diets. Readers are encouraged to consult with healthcare providers for personalized dietary recommendations.