In Part 1 of this blog, I looked at a study that was referenced a lot in my research of why vegetarianism could lead to a healthier lifestyle. It was a huge observational study and eventually concluded that vegetarians live longer than meat eaters. Now, as promised, I’ll look at the other side of the conversation.

A lot of people believe that vegetarianism can actually lead to a less healthy lifestyle because meat contains many important proteins and nutrients that aren’t as prevalent or concentrated in vegetables, fruits, legumes, dairy, and grains.

For example, there is an essential nutrient in meat called vitamin B-12 that is responsible for “keeping the body’s nerve and blood cells healthy and helping make DNA”. It also, “helps prevent a type of anemia called megaloblastic anemia that makes people tired and weak.” However, because vitamin B-12 is only found naturally in meat and dairy products, a strict vegetarian may find it hard to intake the daily-recommended amounts. This deficiency can “boost blood levels of homocysteine, an amino acid implicated as a strong risk factor for heart disease and stroke… [and] promote blockages in arteries over time.

A study published by a team of German researchers in The American Journal of Clinical Nutrition, examined the status of vitamin B-12 in a group of 95 vegetarians (66 lactovegetarians- no meat poultry, or fish and 29 vegans- no food or animal origin) and 79 omnivores, all of which had maintained their current dietary habits for over than a year. The scientists further screened these participants to exclude those that had associations with any of the following…

• Renal disease

• Current consumption of weight-loss diets

• Current pregnancy

• Medication or metabolic diseases known to influence nutritional status.

All subjects were also asked to “complete a preliminary questionnaire about lifestyle factors, the degree of animal-products restriction they followed, and vitamin consumption.” Then, the researchers collected twelve-hour fasting blood samples from all the participants and analyzed the levels of vitamin B-12 using biochemical markers. 

The results showed that 92% of vegans, 66% of the lactovegetarians, and 5% of meat eaters had a vitamin B-12 deficiency. These findings held true even though 17 vegans (59%) and 13 LV-LOV subjects (20%) reported supplementing their diet with bioengineered B vitamins.

How much stock can be put into these findings though? Well let’s analyze the study.

The participant pool was a good sample size (165 people total) and was split between vegetarians (58%) and meat eaters (42%) pretty evenly. As mentioned before, the researchers also controlled for a number of possible confounding variables. Even though the study was partially observational, the researchers did take measurements of the participants’ 12-hour fasting B-12 vitamin levels to see how the x variable (type of diet) affected them. Furthermore, the report of the study is thorough and detailed, allowing the experiment to be easily reproduced. All in all, I’d say that the research was carried out well.

However, there were a few potential flaws. Because participants were responsible for classifying their own diet before the study, researchers really have no way of knowing if what the subjects reported was completely accurate. In addition, even though some confounding variables were controlled, more could exist. Last but not least, as always, the findings could also have been do to chance. 

Ultimately though, I believe that the results of this study should at least be a warning to people considering a vegetarian diet. They don’t necessarily prove that a diet without meat is unhealthy, but they do provide some evidence to support the claim. In my personal opinion, I’d have to do more research before making a final judgment on whether or not vegetarianism is worth it in the long run. It’s also important to remember that many people choose to be vegetarians for reasons other than the potential health benefits. For example, some people don’t eat meat for spiritual or ethical (animal rights) reasons. In the end, it seems like the benefits of vegetarianism are ultimately determined by whether or not an individual believes the potential risks are less than the potential rewards.