Dark chocolate’s link to warding off pancreatic cancer overplayed in media reports, says researcher

A scientist says a New York Daily News article suggesting his new study shows dark chocolate has preventative effects against pancreatic cancer because it contains magnesium is misleading.

Ka He, chair and professor of epidemiology and biostatistics at the School of Public Health at Indiana University Bloomington, and colleagues recently published a paper in the British Journal of Cancer, titled ‘Magnesium Intake and Incidence of Pancreatic Cancer: the Vitamins and Lifestyle Study’.

Surprising link

He told ConfectioneryNews the study doesn’t mention a word about the health benefits of dark chocolate and there is no data support conclusions the confection protects against pancreatic cancer.

“I am surprised to hear that they linked chocolate to pancreatic cancer.”

“We did not look at chocolate in our study. I don’t think we can say chocolate will ward off pancreatic cancer based on this study.”

However, in the NY Daily News article, He did mention chocolate is generally healthy except for its sugar, and it contains magnesium.

“[The NY Daily News journalist] asked me two questions, including a question on chocolate. I thought they were two separate questions,” he added. “I didn’t link chocolate to pancreatic cancer [during the interview].”

Furthermore, He said the NY reporter emphasizes dark chocolate’s superior amount of magnesium compared to pumpkin seeds without giving any attributions, calling it “a silver bullet” because one single square provides around  a quarter of the daily recommended magnesium requirement and more people crave chocolate than pumpkin seeds.

What does the study actually say?

He’s study says pancreatic cancer is the fourth leading cause of cancer-related death in both men and women in the United States. And according to the National Cancer Institute, the overall incidence of pancreatic cancer has not significantly changed since 2002 but the mortality rate has increased an average of 0.4% annually from 2002 to 2011.

Even though there were previous studies that document that magnesium is inversely associated with the risk of diabetes, which is a risk factor of pancreatic cancer, few studies had been done to investigate the association between magnesium intake and pancreatic cancer, the study says.

A few of the key findings of the study include, “a 100 mg per day [decrease] in magnesium intake resulted in a 24% increase in the incidence of pancreatic cancer, and magnesium intake may be beneficial in the primary prevention of pancreatic cancer.”

The truth about dark chocolate

Small daily doses of dark chocolate can help improve blood vessel function in healthy people, according to the Journal of the American College of Nutrition.

However, Euromonitor published a statement in 2013, saying that even though there are growing claims of health benefits, dark chocolate will continue to be consumed as an indulgence.

He, who comes from a nutrition background, didn’t immediately comment on the health benefits of dark chocolate, and how its nutritional value may change dark chocolate’s role in the confectionery industry.

“I have asked the [NY reporter] to revise [the article],” he said.

Source: British Journal of Cancer 2015 113, 1615-1621

doi: 10.1038

'Magnesium intake and incidence of pancreatic cancer: the Vitamins and lifestyle study'

Authors: Daniel Dibaba, Pengcheng Xun, Kuninobu Yokota, Emily White and Ka He.