Ask the Expert: Do Vegetarians Live Longer?

Search Google and you’ll discover millions of articles regarding the pros and cons of both meat-o-phile and meat-free lifestyles. Frustratingly, many of these articles tend to manipulate the data to serve the writer’s oft-dogmatic hypothesis. Frankly, I don’t blame them, given that data on how meat affects the human body tends to be vague and confusing.

There are a few established facts when it comes to how animal product consumption influences our longevity. But for everything we know, there are 10 things we don’t know—and 20 things we think we know that will be disproven before I finish writing this article. So, to some degree, when it comes to dissecting how your body will respond to a specific dietary direction, the ideal strategy is to follow the words of Tao Te Ching scribe Lao Tsu: “To know that you do not know is the best.”

So let’s focus on vegetarianism from an anthropological perspective. And, in case you’re wondering, I’m leaving ethics out of the equation. That’s a topic for a different article.

From a scientific point of view, there’s plenty of evidence out there showing that vegetarians live longer, but that evidence can be easily disputed. There’s also plenty of evidence indicating too much red meat will kill you. But, it’s easy to tear holes in that research. Why? Because absolutes tend to fall apart under scrutiny when it comes to nutritional information.

One of the newest studies on this was published in The Journal of the American Medical Association: Internal Medicine (JAMA: IM) and received a lot of attention in the media. The study looked at the mortality rate of almost 100,000 men and women in North America over a five-year period. The media consistently—and mistakenly—reported the study found that vegetarians outlive meat eaters.

Read the fine print of the study, and you’ll see that pescetarians—those who have a mostly plant-based diet but eat some seafood—were the true winners, with a slightly lower mortality rate than vegans, ovo-lacto vegetarians, and indiscriminate meat eaters. This may have to do with the food, but it could also be because pescetarians tend to put quite a bit of thought into their intricate dietary direction. Because they are often pickier when it comes to the food choices they make, they might do the same when it comes to other aspects of their lives such as exercise, smoking, getting enough sleep, etc.

The JAMA study also overlooked the quality of the animal products, which many experts believe can have a huge impact on the health of the meat eater in question. The longevity of a Big Mac eater is most likely much shorter than the person who regularly dines on wild venison.

The health benefits of a meat-free lifestyle have long been a popular topic. Documentaries such as Forks Over Knives and books such as The China Study by T. Colin Campbell have made compelling cases for going veggo. The China Study, which summarizes a 20-year China/Cornell/Oxford study on the effects of animal products on the mortality rate of thousands of people across China, is the go-to reference for vegetarian longevity.

However, while the study is genuinely compelling, a number of very credible experts have poked holes in it over the years, including Dr. Loren Cordain, author of The Paleo Diet, who suggested that Campbell may have manipulated data to support his vegetarian hypothesis. But meat-heavy diets are probably not the ideal answer either. Relevant research is starting to show that early man’s diet wasn’t the meaty meat fest we had initially believed it to be. A study last year in the American Journal of Physical Anthropology measured nitrogen levels in body tissues, determining that we’ve been overestimating the number of saber-toothed tiger burgers prehistoric humans ate. Given the basic principle of Paleo eating is that our bodies are designed to eat the way our ancestors ate, it looks like we’re supposed to be eating (say it with me now) a largely plant-based diet and some animal products.

When it comes to nutrition, nothing is black and white. Meat isn’t bad. But, what is starting to come out of these studies is that less meat is better. When it comes to nutrition, nothing is black and white. Meat isn’t bad. But, what is starting to come out of these studies is that less meat is better. Even the World Health Organization seems to agree with this point, considering their recent pronouncement regarding the carcinogenic nature of processed meat and the (potentially) carcinogenic nature of red meat. Here’s another example. In The Blue Zones, National Geographic journalist Dan Buettner searched the globe for “blue zones,” areas where people often lived healthy, fruitful lives well into their 90s. One common factor of the four zones featured in his book—Sardinia, Italy; Okinawa, Japan; Loma Linda, California; and the Nicoya Peninsula, Costa Rica—was that their inhabitants all ate a largely plant-based diet as well as some animal products.

Nutrition gurus including Dr. Dean Ornish (author of Eat More, Weigh Less) and author Michael Pollan (author of The Omnivore’s Dilemma and In Defense of Food)—whose slogan is “Eat food. Not too much. Mostly plants.”—also endorse this notion of animal product moderation. As renowned food writer Marion Nestle says in her book What to Eat, “Fruits and vegetables are the one point of consensus—an oasis—in arguments about what to eat. Everyone agrees that eating more of them is a good idea.”

Yet, while there’s certainly a pattern emerging here, the specifics are still unclear. What kind of animal products? How much is “some”? To answer these questions, I suggest turning your focus of research to your own body. Generally speaking, you’ll live longer if you’re healthier, and what makes individuals healthy shifts from person to person (a theory known as “biochemical individuality”). Pay attention to how your diet affects you. How do you feel? How are your moods? How is your energy level? What’s your weight?

If you really want to earn your white lab coat, check your blood work. I’ve been a pescetarian for 13 years (and an ovo-lacto vegetarian for five years before that). My doctor continues to be blown away by my cholesterol levels. “Some people would pay a lot of money for blood like yours,” he marveled at my most recent check-up. So clearly, I’ve found a system that works. For me.

Any diet you choose should have a solid foundation of fruits and veggies, but the amount of animal products you consume depends on the most valuable research tool you have: You.

In case you are looking for vegetarian meals, there are lots of them on the site. Just click here for the list.