12 January - 20 June 2016

Vegetarian diet may influence gene variant frequency

A study led by researchers from Cornell University and published in Molecular Biology and Evolution, suggests that cultures that have eaten a vegetarian diet for many generations may have developed a gene mutation which could lead to an increased risk for heart disease and colon cancer if they change to a more omega 6 rich diet.

A study led by researchers from Cornell University and published in Molecular Biology and Evolution, suggests that cultures that have eaten a vegetarian diet for many generations may have developed a gene mutation which could lead to an increased risk for heart disease and colon cancer if they change to a more omega 6 rich diet.

Fatty acids are known to play an important role in storing energy and in the growth and repair of cells. It is noted that the body can produce all the fatty acids required except for omega-6 fatty acids and omega-3 fatty acids which must be obtained from food. While carnivores can get these from meat consumed, vegetarians must produce their own by metabolising fatty acids directly from plant–based foods.

Enzymes FADS1 and FADS2 are used to break down omega-6 and omega-3 fatty acids for the human body to use.  Breena et al. identified a gene variant known as r66698963 which is in the gene responsible for expressing these enzymes. The team notes this variant causes an increase in the production of these enzymes and so increasing the ability to produce fatty acids from plant-based foods.

The researchers examined r66698963 variant frequency both experimentally and using data from the 1000 Genome Project (GP). Experimental frequencies were determined for 311 mainly meat-eating individuals from the Kansas area and 234 mainly vegetarian individuals from Pune, primarily a vegetarian area.  The mutation frequencies were 18% and 68% for the Kansas and Pune participants respectively. Analysis of the 1000 GP data showed that the highest frequencies of the insertion mutation were to be found in South Asia (70%) and Africa (53%) while East Asians (29%) and Europeans (17%) showed a much lower frequency.

While the insertion mutation can help vegetarians, having too much omega-6 in the diet compared to omega-3 is associated with health risks. It is noted that omega-6 and omega-3 compete to be metabolised and so an increased level of omega-6 can lead to an imbalance which is linked to increased risk of heart disease and colon cancer.

Two of the researchers, J Thomas Brenna and Kumar Kothapalli, are quoted in a press release as saying that “with little animal food in the diet, the long chain polyunsaturated fatty acids must be made metabolically from plant PUFA precursors. The physiological demand for arachidonic acid, as well as omega-3 EPA and DHA, in vegetarians is likely to have favoured genetics that support efficient synthesis of these key metabolites" but added that "changes in the dietary omega-6 to omega-3 balance may contribute to the increase in chronic disease seen in some developing countries."

In conclusion, the study states the data suggests that r66698963 mutation contributes to the variable response to fatty acid consumption across individuals and that an appropriately balanced consumption fatty acids would be important for individuals with the insertion mutation.

RSSL has expertise in all aspects of fat analysis and fatty acid profiling, including the determination of omega-3 and omega-6 fatty acids. For more information please contact Customer Services on +44 (0) 118 918 4076 or email enquiries@rssl.com 

share this article
RSSL endeavours to check the veracity of news stories cited in this free e-mail bulletin by referring to the primary source, but cannot be held responsible for inaccuracies in the articles so published. RSSL provides links to other World Wide Web sites as a convenience to users, but cannot be held responsible for the content or availability of these sites. This document may be copied and distributed provided the source is cited as RSSL's Food e-News and the information so distributed is not used for profit.

Previous editions

Load more editions

Make an Enquiry