Vegetarians are happier.
At least this is what recent research is suggesting. This finding somewhat goes against what might be expected because of the vegetarians lower intake of certain fatty acids found especially in fish, especially the long chain omega- 3 fatty acids that have been associated with good mental health.
Long chain simply means there are more carbon atoms than in omega-3 short term fatty acids. EPA-eicosapentaenoic acid and DHA-docosahexanoic acid are long chain omega-3 fatty acids. Another player in the game is AA or arachidonic acid which is an unsaturated fatty acid found in chickens, red meat, eggs, dairy and some fish.
AA has been marketed as a body building supplement in a variety of products and in general is considered to be beneficial to the body.
However it might be likened to a Dr. Jekyll and Mr. Hyde substance because it can cause inflammation in certain cases. In the March 1996 journal Lipids a study of 20 moderately to severely depressed patients found higher levels of AA as compared to the levels of EPA correlated to more severe depression.
Before the studies that showed vegetarians are happier are discussed, mention needs to be made of two other players. There is ALA — alpha-linolenic acid — a short-chain omega-3 fat and LA — linoleic acid — a short chain omega-6 fat. ALA is found in seed oils with the highest levels in chia seed and the lowest levels in soybean oil. LA is found primarily in plants but also found in chickens, eggs and lard.
The body is able to convert ALA to EPA and DHA but it is not done very efficiently. So on the surface it would appear that since EPA and DHA have important roles to play in brain function and since vegetarians get very little of those two fatty acids the mood of vegetarians would be adversely affected. Two recent studies have shown this is not the case.
The 2010 Nutrition Journal reports a study done on 138 healthy Seventh-day Adventist men and women. Approximately half of them were vegetarians and the other half were omnivores.
They were all anonymously surveyed with a general health history questionnaire, a food frequency questionnaire and two psychological tests, the Depression Anxiety Stress Scale and the Profile of Mood States. The vegetarians experienced significantly less negative emotions than the omnivores.
In 2012 the Nutrition Journal reported another study by some of the same authors as the 2010 study. This time, since happiness and mood are subjective states, the participants were blinded as to the purpose of the study.
In this study 39 omnivores were divided in to three groups. The OMN group ate meat, fish and poultry daily. The FISH group at fish 3-4 times weekly but avoided meat and poultry and the VEG group avoided meat, fish, and poultry.
At the beginning and the end of this study participants were given the same four tests that had been administered to the 138-person study.
Amazingly the VEG group who had previously been omnivores showed significant improvement in their moods. The moods did not change for the OMN or FISH groups.
The big question is how could this come about? The suggested explanation was that the vegetarian diet had a higher intake of polyunsaturated fats with very little AA and that the higher antioxidant levels in plant products reduced the psychological stress that has been associated with the free radicals that the body produces with its normal bodily functions.
Dr. Don Casebolt of College Place is a retired physician who is passionate about preventive medicine. He spent four years as a medical officer in the U.S. Navy, the last 21/2 years as a flight surgeon. He also worked on the Navajo Reservation for 22 years.