New research from Cornell University has found that, over hundreds of generations, vegetarians develop a different set of genes.
Indeed, Cornell researchers describe different version of a gene (called allele) that has evolved in populations having vegetarian diets, for example in India, Africa and parts of East Asia.
A different version of this allele but adapted to a marine-rich diet was discovered among the Inuit in Greenland, who mainly consume seafood.
The vegetarian allele allows populations to process short-chain plant-based omega-3 and omega-6 fatty acids into the equivalent of fish oil long-chain omega-3 which is essential for early brain development and controlling inflammation. The Inuit allele has almost the opposite effect.
Normal humans need both long-chain omega-3 (typically in fish oils) and short-chain omega-3 (typically in flaxseed). Only 14 per cent of short-chain omega-3 can convert to its long-chain cousin, in normal humans.
Kaixiong Ye, was co-lead author of the paper appearing March 29 in the journal Molecular Biology and Evolution. Ye is a postdoctoral researcher in the lab of Alon Keinan, associate professor of biological statistics and computational biology, and the paper’s co-senior author.
FADS1 and FADS2 are enzymes that are essential for converting omega-3 and omega-6 fatty acids into ‘downstream products’ needed for brain development and controlling inflammation. Meat and seafood eaters have less need for increased FADS1 and FADS2 enzymes to get proper nutrition because their omega-3 and omega-6 fatty acid conversion process is simpler and requires fewer steps.
“One implication from our study is that we can use this genomic information to try to tailor our diet so it is matched to our genome, which is called personalized nutrition,” said Ye.
’Going vegetarian’ may be counter-productive
Many people with cancer, especially women, give up meat and go ’Vegetarian’ or ’Vegan’. The conclusion from this study is that might not be wise.
Many National Newspapers in the UK have provided headlines from this research saying that vegetarians thus have higher risk of cancer and heart problems because they have no anti-inflammatory compound production system, (no allele) to give them the equivalent of anti-inflammatory fish oil omega-3. As a result, for example, secondary and inflammatory bile acids are produced in the gut.
This is not a totally accurate conclusion of the research. It is possible that new generation vegetarians who consume no long-chain omega 3 might be at greater risk, but not long-term vegetarians from families of vegetarians who have the allele. But clearly it is a concern.
The study was funded by the National Institutes of Health and the U.S. Department of Agriculture.