Gastro doctor Dr Pal finds the 'one food' heart patients must avoid: Chennai-based cardiologist reveals

In a recent Instagram post, California-based gastroenterologist Dr Palaniappan Manickam, popularly known as Dr Pal, shared a clip from his podcast conversation with Prof. Dr Babu Ezhumalai, a senior interventional cardiologist from Chennai. During the discussion, Dr Pal asked a direct question that many heart patients often wonder about but rarely ask aloud: as a cardiologist, which one food would you most want patients to avoid?

The response was immediate. Dr Ezhumalai named potato fries.

Why potato fries raise cardiac concerns

Explaining his reasoning, Dr Ezhumalai pointed out that potatoes are root vegetables naturally high in starch. However, the larger issue arises during cooking. When potatoes are deep-fried in oil at high temperatures, they tend to develop trans fatty acids. According to the cardiologist, these fats are strongly linked to heart problems and are best avoided, particularly by individuals with existing cardiac risk.


He also highlighted a familiar household pattern. Potato fries are among the most popular foods for children globally and are frequently prepared at home or purchased from outside. This widespread consumption, he noted, makes them an underestimated contributor to unhealthy fat intake.

The remarks were shared as part of the podcast clip circulated on Dr Pal’s official Instagram account, from which the quoted insights are drawn.

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A post shared by Dr. Pal Manickam (@dr.pal.manickam)

Dr Palaniappan Manickam is a board-certified gastroenterologist practicing with the Dignity Health Medical Foundation in Carmichael, California. Originally from Madurai, he is widely known for blending medical education with humour, a style he calls MedCom.

Prof. Dr Babu Ezhumalai is a senior consultant interventional cardiologist and heart failure specialist based in Chennai, with over 18 years of clinical experience. He is known for handling complex cardiac interventions, including advanced angioplasty, stenting and structural heart procedures such as transcatheter aortic valve replacement.

What broader research says about fries and metabolic risk

Emerging research strengthens this cautionary view of potato fries beyond heart health. A large long-term study published in The BMJ and reported by Prevention tracked over 205,000 adults across three major U.S. health cohorts for nearly 30 years. It found that people who consumed French fries three or more times a week had up to a 20 percent higher risk of developing type 2 diabetes compared to those who ate them rarely. Crucially, this elevated risk was not seen with potatoes prepared by boiling, baking or mashing, pointing to cooking method rather than the vegetable itself as the key concern.

Experts involved in the research noted that deep frying increases calorie density, unhealthy fats and inflammation, while reducing fibre that helps regulate blood sugar. The study also observed that replacing fries with whole grains such as oats or quinoa significantly lowered diabetes risk, reinforcing the importance of carbohydrate quality. Together, these findings underline that frequent consumption of fried potatoes may carry long-term metabolic consequences, complementing cardiologists’ warnings about their impact on heart health.

Rethinking everyday comfort foods

The conversation serves as a reminder that foods often perceived as harmless comfort snacks can carry hidden risks, especially when cooking methods introduce harmful fats. For heart patients and families alike, the cardiologist’s message underscores the importance of looking beyond sugar and salt, and paying closer attention to how everyday foods are prepared and consumed.