ergo-log.com

Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "

16.01.2023

High intake of nuts and legumes protects against brain cancer

Glioma is a fortunately rare but difficult to treat type of brain cancer. A small epidemiological study suggests that a diet high in beans and nuts may reduce the risk of glioma.

Study
Researchers at Tehran University of Medical Sciences in Iran published a study in 2021 involving 128 men and women who had just been diagnosed with a glioma.

Using questionnaires, the researchers determined the diet of the patients. They also did this with a control group of 256 study participants who were free of cancer but resembled the patients in terms of sex and age.

Results
The more legumes and nuts the study participants consumed, the lower the risk of glioma.

It is possible that beans and nuts are part of a healthy lifestyle, and that this Iranian study measures the effect of that healthy lifestyle. The researchers therefore brushed aside as many of these other lifestyle factors as possible, but found that this did not reduce the protective effect of nuts and beans.

Mechanism
The Iranians don't know how beans and nuts are supposed to reduce the risk of glioma. They point to a Chinese in vitro study in which computer modeled lectins in beans can kill cancer cells. [Cell Prolif. 2013 Feb;46(1):86-96.]

The researchers also refer to an Italian in vitro study in which vitamin E inhibits glioma cells. [Free Radic Biol Med. 2006 Aug 1;41(3):464-72.] Nuts are a good dietary source of vitamin E.

Epidemiology
Epidemiological research can find associations, but not every association in an epidemiological study is causative. This objection also applies to the Iranian study - which is a case control study.

In case control studies, epidemiologists often study people who have just received an extremely unpleasant message. You can expect them to be impressed and perhaps wonder what they did to bring this on.

If you ask these people if they want to describe their lifestyle, it is quite possible that their answers will be colored by ideas about what is healthy and what is not. That is why some caution is in order with the interpretation of case control studies.

Source:
Nutr Cancer. 2021;73(5):760-6.

More:
Walking and running can halve the chance of brain cancer 18.05.2014

Archives:
Cancer Prevention
Legumes
Nuts

Reduction of prostate cancer risk by a few tablespoons of beans a day Men who eat an average of three large tablespoons of peas, kidney beans or other legumes every day roughly halve their risk of prostate cancer.	Eating lots of walnuts helps fight prostate cancer Walnuts contain substances that sabotage the spread and growth of prostate cancer tumours.	Nuts halve mortality risk in colorectal cancer Nuts fit into a healthy diet. You already knew that, and that people who frequently consume nuts reduce their risk of cancer will not surprise you either.