Some People Are Genetically Programmed To Eat A Vegan Diet, Some People Aren't

Like many of you, I have some friends who pursue a rigorously vegan diet. Well, actually "friend" may be overstating the closeness of our relationship. We belong to the same church. Every time they talk the subject is why their diet is superior to everyone else's and the problem with meat eaters is they are weak and ignorant. You may know people like that.

Also like many of you, I have friends who are essentially carnivores. They eat meat at every meal, and almost nothing else. In my social setting, people don't claim superiority for being meat eaters. They just eat meat. I find it easier to interact with my meat-eating friends. I am myself an omnivore, that is, I eat all kinds of foods. I limit the amount of meat I eat to the protein I think I need, and I avoid eating foods that I know take a toll on the environment. I haven't always done that, but I do now.

Moral issues aside, many people are absolutely sure that a mostly-meat or an all-plant diet is best for health for every human being on the planet. Recent scientific investigation has found that the truth is that different diets are better for different people, on account of genetics.

Meat Is the Main Source of an Essential Fatty Acid

Dr. Kaixiong Ye, a researcher at Cornell University, has announced the discovery of a gene that gives some people an unusual ability to thrive on a vegetarian diet. This gene, named FADS2, gives some people to synthesize a compound called arachidonic acid.

Arachidonic acid is sometimes portrayed as a toxic substance, but the truth is that it is essential for human life. Although it is a n-6 fatty acid and n-6 fatty acids are associated with the body's production of inflammatory hormones, arachidonic acid is also an important building block in nerves, muscles, and the liver. It forms up to 20 percent of the membranes that line cells in these organs, and it is essential for conducting signals from adjacent cells and the rest of the body to the cell so it can function as part of a tissue. Arachidonic acid is a building block of the hormones that the body needs when it is in "fight or flight" mode, and it's essential for limiting bleeding and for activating the immune system.

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Arachidonic acid is a "conditionally essential" fatty acid. Our bodies can make arachidonic acid out of another fatty acid called linoleic acid. This precursor fatty acid is abundant in olive oil and oils pressed from sunflower seeds, hemp seeds, and sesame seeds. It comprises over half the fatty acids in soybean oil, corn oil, and poppyseed oil. If you have ever stepped on a cockroach, the disagreeable smelling oil that oozes out of the roach's body is largely linoleic acid.

The reason arachidonic acid is "conditionally" essential is that even though our bodies can make it, they can't always make enough of it. The only way many people (and some animals, house cats, for example) can get enough arachidonic acid is to eat meat, and lots of it. However, some people don't have to eat meat.

Genetic Differences Between Vegans And Meat Eaters

The researchers at Cornell University found that 68 percent of people in India but only 18 percent of people in the United States have the variation of the FADS2 gene that allows their bodies to make arachidonic acid from plant fats. This gene codes a series of enzymes that convert not just linoleic but other fatty acids into arachidonic acid for normal health. People who do not have this gene can make some arachidonic acid, enough to avoid death, from the linoleic acid in plant seeds, but to be truly healthy they need to eat the beef, eggs, and other kinds of red meat that provide arachidonic acid in a easily digestible form.

The fact that 32 percent of people in India do not have the variation of the FADS2 gene that permits health on vegan diets may explain why some diseases are more common in India. The fact that 18 percent of Americans do have the FADS2 gene explains why some people get really good results on vegan diets, but others do not respond.

Certain ethnic groups tend to have the vegan diet gene, including:

• 68 percent of people in South Asia,
• 53 percent of people in East Africa,
• 29 percent of people in East Asia,
• 17 percent of Europeans, and, as previously mentioned,
• 18 percent of Americans (about half of whom are not of European ancestry).

What is the importance of these findings? For nearly a generation, experts have been telling us that Americans and Europeans consume too many omega-6 fatty acids, the kind of fatty acids the body can turn into inflammatory hormones. They get too much fat from meat, eggs, and plant seed oils that are rich in the precursors of arachidonic acid. What Americans and Europeans need to do, experts say, is to eat a diet closer to that of East Africa or South Asia.

Now we know that for the overwhelming majority of Americans and Europeans, meat, specifically red meat, along with eggs, is an essential part of the diet. Deprived of meat and eggs, people with their variation of the FADS2 gene suffer weakened immunity, weakened brain function, muscle deterioration, and liver problems.

No one should be told their diet is inferior because it does or doesn't include meat.

What should you do if you believe you probably have the gene that makes your body require arachidonic acid but you don't choose to eat animals for moral reasons? First of all, your choices are valid. You have chosen the health of animals over your own. The issue is that you need to take extra measures to make sure you get the fatty acids you need.

READ Pros and Cons of the Vegan Nutritional Style

There are arachidonic acid supplements made from the fungus Mortierella alpina. You need to get a product labeled as arachidonic acid, not a product labeled as gamma-linoleic acid or GLA (which provide the fatty acid plant foods that your body can't use well enough to keep you well). Arachidonic acid supplements are not especially expensive, and they give your many of the advantages that your genotype would normally get from eating meat. For most Americans, vegan diets actually aren't the healthiest option, but they are still possible.