Cooking meat at high temperatures leads to production of carcinogens.
The incidence of renal cell carcinoma (RCC), the most common form of kidney cancer in adults, has been increasing in the US and other developed nations.
Previous studies have linked meat intake with an increased risk of RCC. The underlying mechanism for the association remains unclear, but cooking meat at high temperatures, particularly barbecuing or pan-frying, has been found to result in the formation and ingestion of carcinogenic compounds.
The kidney plays a significant role in the metabolism of xenobiotics, substances normally alien to the body, such as drugs, pesticides or carcinogens, and is therefore exposed to higher concentrations of cancer-causing substances than other organs.
Meat cooked at high temperatures produces carcinogens
A team led by Dr. Xifeng Wu, PhD, of the University of Texas MD Anderson Cancer Center in Houston, suspected that factors related to a Western lifestyle – such as a diet high in meats, processed foods and starches – may significantly impact the development of RCC.
They set out to investigate the effect of genetic factors and dietary intake of meat-cooking mutagens, such as MeIQx and PhIP, on RCC risk. An analysis was carried out of 659 patients with newly diagnosed RCC and 699 healthy controls.
Compared with cancer-free individuals, patients with kidney cancer were found to consume more red and white meat; they also consumed more cancer-causing chemicals, produced by cooking meat at high temperatures or over an open flame, particularly when pan-frying or barbecuing.
People with RCC were also found to have an overall higher daily total energy intake and lower overall total fruit and vegetable intake.
Fast facts about kidney cancer
- In 2005, more than 36,000 people were diagnosed with kidney cancer in the US
- In 2014, there were over 50,000 diagnoses
- There are currently 200,000 kidney cancer survivors in the US.
Ingestion of MelQx would seem to nearly double the risk of RCC, and intake of PhIP increases it by 54%. This suggests that eating meat cooked at high temperatures increases the risk of RCC through mechanisms related to mutagenic cooking compounds.
A significant interaction was noted between PhIP and at least one genetic feature, implying that individuals with certain genetic variants are more susceptible to the harmful effects of these cancer-causing chemicals.
Limitations of the current study include the possibility of residual confounding by unknown risk factors and the difficulty of isolating the impacts of the mutagenic compounds, due to the complex interaction of individual components and nutrients in whole foods.
Nevertheless, the findings suggest that reducing meat consumption, especially when cooked at high temperatures or over an open flame, could serve as a public health intervention to reduce the risk of developing RCC. In addition, genetic testing might help to identify individuals at especially high risk.
Medical News Today recently published findings linking a drug commonly used for heartburn with kidney cancer.
Written by Yvette Brazier