Vegetarians are at higher risk of suffering depression compared to those who eat meat and consume a conventional balanced diet, according to a new study.
A Bristol University study of almost 10,000 people from southwestern England discovered that vegetarians were almost twice as likely to develop depression because of vitamin and mineral deficiencies that can negatively impact their mental health.
The 350 committed vegetarians who participated in the study had a higher average depression score when compared to the meat eaters, according to the study published in the Journal of Affective Disorders.
Without meat, a vegetarian's diet tends to have less vitamin B12 consumption, as well as greater intake of nuts that contain omega-6 fatty acids, which have been linked with an increased risk of mental health problems.
In addition, roughly 50 percent of vegans and 7 percent of vegetarians have a vitamin B12 deficiency. Vitamin B12 can be found in red meat and plays an important role in affecting an individual's mood.
"Other potential factors include high blood levels of phytoestrogens (estrogen that's naturally in legumes) - consequent mainly on diets rich in vegetables and soya," the report stated. "Another potential contributing factor is that lower intakes of seafood are thought to be associated with greater risk of depressive symptoms."
The lack of a balanced diet can influence the development of depression.
Research findings also can be attributed partially to iron deficiencies, the study says.
Participants who had been consuming a vegetarian diet for longer periods of time had higher depression scores throughout.
The study, however, did not rule out the possibility that the vegetarians' decisions to adopt their diet could have been a symptom of depression from the get-go.
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