Is a Vegetarian Diet REALLY Healthy? (you may be surprised)

Is the Vegetarian Diet Healthy

“Are vegans healthy? Is a vegetarian diet healthy? French fries and beer are vegan, so you tell me?”

That’s the introduction to a popular online advertisement, and although it’s obviously hyperbolic, I love it and think it’s spot on. Within that simple series of questions lies the answer to the increasingly common question: Is a vegetarian diet healthy?

I think you’ll be surprised to find the answer is both straightforward yet nuanced. Most importantly, whether you’re a devout vegan, an adamantly-opposed carnivore, a curious omnivore, coming off a fling with Veganuary, or anywhere in between, the answer is relevant and extremely important.

What Does it Mean to be Vegan or Vegetarian?

To be honest, this is one of my most pressing questions. After all, there are seemingly endless variations of vegetarianism. That makes it quite challenging to answer the question “is vegetarianism healthy.” 1

On one hand, you’ve got vegans, who basically limit themselves to only plant-based foods. While there are some “branches” of veganism (e.g., raw vegans), folks who fall under the umbrella of vegans share the defining characteristic that they avoid all animal-based food products (e.g., meat, poultry, dairy, fish, eggs, etc.).

And then you have vegetarian diets. That’s where the lines get pretty murky. For example, you have strict vegetarians (who only consume plant-based foods, basically vegans). You’ve also got the lacto-ovo-vegetarian diet, which includes dairy and egg products. There are also lacto-vegetarians (who include dairy only) and ovo-vegetarians (who include eggs only).

Then there’s the pescatarian diet, which tends to be largely plant-based yet includes fish and seafood (but excludes other animal-based products). And you even have macrobiotic vegetarianism, which has variable restrictions and often includes wild meat and fish. Then there’s the fruititarian approach, which centers on fruits, nuts, seeds, and some vegetables.

And of course, there’s been a surge in the flexitarian-style of eating, which emphasizes a plant-based diet. Yet as the name implies, it allows the flexibility to consume non-vegetarian foods. In other words, flexitarians are part-time or semi-vegetarians.

Oh, and speaking of part-time vegetarians, have you heard of Veganuary? It’s one of the hot fitness trends this year that inspires people to give vegan a test drive for the month of January. (Kind of like Dry January, which involves going sober for the month.)

There’s nothing “wrong” with these variations of vegetarianism. In fact, as you’ll see, I believe a slightly modified vegetarian diet may be optimal. However, I point out the vegetarianism soup because the variations (and sometimes wild differences) make it quite challenging to speak generally about vegetarianism.

Cliff Notes: Is a Vegetarian Diet Healthy?

If you’re too busy to read the entire article, believe me, I get it. So, let me shoot it to you straight. Yes, vegetarianism can be healthy. In fact, I’d go so far as to say you could quite easily make the argument that a well-planned, whole-food plant-based diet may be an optimal dietary strategy, particularly one that addresses the concerns shared below.

That should carry some weight coming from someone whose eating patterns would be best described as omnivore. While I lean heavily toward plant-based foods, I regularly consume whole foods you’d never find on a vegan’s plate (e.g., meat, poultry, eggs, and fish).

Just to reiterate, I want to emphasize that a vegetarian diet can be healthy—very healthy, in fact. However, just because you limit yourself to vegetarian-friendly options doesn’t make you inherently healthier. And while the overwhelming majority of folks would be doing themselves and the environment a tremendous service by eating more whole, minimally processed plant-based foods, here are my three primary concerns with vegetarianism:

  1. Just because a food is vegan/vegetarian doesn’t necessarily = healthy.
  2. There are multiple nutrients of concern that are less abundant in plant-based diets (i.e., potential nutrient insufficiencies).
  3. It’s not for everyone, all the time.

Simply put, a vegetarian diet can be both healthful and unhealthful. But even the most carefully-planned vegetarian diets may leave several important bases uncovered. 2, 3, 4

What Are the Benefits of Vegetarianism?

Whether you’re a strict vegan or full-time carnivore, you’ve likely noticed that vegetarianism has become increasingly popular over the last several years. According to a recent survey, the number of vegans in Britain has risen by over 250% in the last decade alone. And if you ask the Vegan Society, veganism is one of the “fastest growing lifestyle movements.” 5

While a recent Gallop poll suggests the percentages of Americans saying they are vegetarians or vegans has changed little over time, there’s little denying that vegetarianism is becoming more popular. 6 Take, for example, Veganuary, the movement to encourage and support folks to try a plant-based diet (at least for a few weeks). Since it became a thing five years ago, the number of Veganuary participants have more than doubled each year.

The surge in popularity can likely be traced, in large part, to increased visibility thanks to the proliferation of social media and endorsements from high-profile celebrities (such as Ellie Goulding, Jennifer Lopez, and Liam Hemsworth) and athletes (including Kyrie Irving, Venus Williams, and David Haye).

Quite often, folks choose vegetarianism because of strong ethical beliefs about animal welfare. In other words, a love of animals is the catalyst for many people who opt for a vegan lifestyle.

That’s quite a contentious and polarizing topic, and it’s not one I will discuss in this article. If you do choose to consume animal-based products—like I do—I advise opting for foods that come from animals that are humanely treated, sustainably raised, fed in the most natural way possible, and not subject to artificial growth hormones and antibiotics.

Having said that, the perceived benefits of vegetarianism seem to be a driving force behind the trend. Advocates of vegetarianism tout a long list of alleged health benefits, so let’s sort between fact and fiction. When it comes to the question of “Is a Vegetarian Diet Healthy?”, here are three evidence-based benefits.

#1: Better Diet Quality. Generally speaking, a healthy vegetarian diet is composed of minimally-processed whole foods such as:

  • Vegetables (all types and varieties, including dark leafy greens, cruciferous vegetables, root vegetables, starchy vegetables, etc.)
  • Fruits (all types and varieties)
  • Legumes (e.g., beans, lentils, peas, peanuts)
  • Nuts (e.g., almonds, pecans, walnuts)
  • Seeds (e.g., chia, flax, hemp, pumpkin)
  • Whole grains (e.g., quinoa, oats, brown rice, sprouted grains, amaranth, etc.)

While an obvious characteristic of vegetarianism is reducing animal-based foods, it also tends to limit added fats and oils. And ideally, it should (but doesn’t always) involve avoiding (or at least limiting) refined, processed carbohydrates (such as added sugars and refined grains).

The Academy of Nutrition and Dietetics Position Paper states that vegan and vegetarian diets “are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain disease.” 7 The advantages of plant-based diets are likely due to the combination of innate health-promoting compounds found in whole plant-based foods and the reduction of potentially harmful substances found in highly processed foods.

For example, highly processed foods typically include added poor-quality oils, sugar, salt, and other food additives. These can contribute to excess oxidative stress and persistent, unhealthy levels of inflammation. Meanwhile, there are pervasive concerns about processed meat and animal products, although some are not substantiated by research.

On the other hand, plant-based foods, which are typically high in micronutrient density (vitamins and minerals), feature two exclusive nutrients: fibers and phytonutrients. Fibers offer an array of powerful properties and help support digestive, cardiovascular, and immune system health. Meanwhile, phytonutrients (such as glucosinolates, carotenoids, and flavonoids) work synergistically to reduce inflammation and oxidative stress, providing superior health protection. 8

While one could certainly argue that commonly-used measures of dietary quality (such as the Alternate Healthy Eating Index, AHEI, and the US Healthy Eating Index, HEI) have some degree of subjectivity, whole-food plant-based diets and dietary patterns higher in healthy plant foods (even if not exclusively plant-based) consistently rank highly for overall diet quality. 3,9 However, while vegetarianism can (and often does) lead to better diet quality, as you’ll see below, that’s not always the case.

#2: Better for the Body. According to an analysis of risk factors from 1990 – 2010, the leading cause of early death and disability in the United States is diet. 10 Even more, the authors state, “The most important dietary risk in the United States are diets low in fruits, low in nuts and seeds, high in sodium, high in processed meats, low in vegetables, and high in trans fats.”

When you consider the above, it’s easy to begin to see why diets that lean heavily toward whole-plant-based foods can be so healthful. And along those lines, it’s not surprising that vegetarian diets that emphasize whole, minimally processed foods can contribute to the following list of health benefits: 8,11,12

  • Lowering the risk of overall mortality (i.e., death)
  • Lowering the risk of mortality from heart disease
  • Reducing medication needs
  • Supporting weight loss and sustainable weight management
  • Reducing the incidence and severity of obesity
  • Reducing markers of inflammation associated with obesity
  • Improving glycemic control and glycemic balance
  • Reducing hypertension
  • Reducing the risk of certain forms of cancer
  • Improving blood triglycerides and cholesterol
  • Reversing advanced cardiovascular disease
  • Preventing, managing, and even reversing type 2 diabetes

That’s quite an impressive list. It’s also solid evidence that vegetarianism can be quite healthy. But it’s important to point out what this doesn’t mean: Vegetarianism is NOT healthier than other dietary patterns that emphasize whole, minimally processed foods, such as a Mediterranean-style diet, for example. These are simply health benefits that have been associated with whole-food plant-based diets.

#3: Better for the Planet. In a recent study published in The American Journal of Clinical Nutrition, researchers from Tulane University and the University of Michigan built an extensive database of greenhouse gas emissions (GHGE) related to the production of foods. They found plant-based diets had a lower carbon footprint than diets that included more animal products (such as meat and dairy). 3

The researchers also rated the nutritional value of foods consumed (using the U.S. Healthy Eating Index, a measure of diet quality) and found diets with the lowest carbon footprint were healthier (at least by this index’s standards). In other words, according to this study, plant-based diets are not only better for the planet, they also tend to be healthier (although that’s not always the case).

This is a supremely important advantage of plant-based diets. Food production is a major contributor to climate change—due to GHGE. And researchers have estimated that GHGE can be reduced by up to 50% simply by reducing the amount and types of meat and eating more plant-based foods in their place. 13

According to Martin Heller of the University of Michigan Center for Sustainable Systems at the School for Environment and Sustainability, “The good news here is that there are win-win solutions with diets that are healthier for people and planet. Big reductions in food-related emissions don’t require eliminating food entirely: moderate shifts away from red meat and toward beans, eggs, or chicken can lead to significant improvements in both health and our diet’s carbon footprint.”

What are the Concerns of Vegetarianism?

Above we listed a lot of positives to the question “Is a Vegetarian Diet healthy”, it is only fair to look at the other side. Here are some of the most pressing concerns of vegetarianism.

#1: Shortfall Nutrients of Concern. While a well-formulated whole-food plant-based diet is characterized by high nutrient density and the Academy of Nutrition and Dietetics states that vegetarian diets are “nutritionally adequate,” there are several notable “nutrients of concern” frequently lacking in vegetarian diets. 4,8,14

  • B12. Cobalamin, commonly referred to as vitamin B12, deserves special attention because it is the only nutrient not directly available from plants. Rather, B12 is only naturally found in animal products where it is formed by bacterial fermentation. B12 is necessary for brain health, cognitive function, nervous system function, methylation, heart health, gastrointestinal health, and more. While some plant-based foods are fortified with B12, it’s typically an inferior, potentially damaging form called cyanocobalamin. Instead, plant-based eaters should supplement with the bioactive form, methylcobalamin.
  • Vitamin D. While few foods, in general, naturally contain the “sunshine vitamin” (fatty fish, liver, and eggs are a few examples), the primary plant-based source is mushrooms. Even then, the plant-based form of vitamin D (D2) seems to be less effective than D3 (which comes from animal sources) at raising blood levels of vitamin D, which plays an important role in seemingly countless physiological processes. The obvious solution is to spend time in the sun (without sunscreen, with your bare skin exposed), but that’s not always an option, in which case, supplementation is ideal.
  • Vitamin K. While dark leafy green veggies are a great source of vitamin K—which is essential for healthy, flexible arteries, heart health, bone health, and blood coagulation—they provide vitamin K1. Yet it’s becoming increasingly clear that vitamin K2—which is produced by bacterial fermentation and found in some meat, dairy, and eggs from pasture-raised animals as well as fermented foods (e.g., yogurt, natto)—is optimal (and perhaps necessary). For example, K2 is much better used by the body than K1, of which only about 10% is absorbed.
  • Iron. While iron consumption isn’t necessarily an issue for plant-based eaters, who tend to consume a diet rich in iron-containing whole grains and legumes, absorption is a problem. You see, plant-based iron (non-heme iron) is far less bioavailable than heme iron from animals. On top of that, plant-based foods often contain anti-nutrients that can inhibit the absorption of minerals, such as copper, zinc, calcium, and iron, which is an essential component of hemoglobin.
  • Zinc. Speaking of minerals, zinc is an essential component of over 300 enzymes, which are the catalysts for every metabolic reaction in the body. Among its many functions, zinc supports immune function and the synthesis of proteins and DNA. Just like iron, plant-based diets tend to contain a decent amount of zinc, it’s just that it is poorly absorbed. The Institute of Medicine suggests plant-based eaters might need to consume up to 50% more zinc than non-vegetarians.
  • Choline. Often overlooked, choline is an essential nutrient often grouped with B vitamins. While choline—which plays critical roles in nervous system function and development, supports methylation, and is a precursor to the brain chemical acetylcholine (important for memory, mood, muscle control, and more)—can be found in small amounts in plant-based foods, recent research indicates “it is extremely difficult to achieve the AI [adequate intake] for choline without consuming eggs or taking a dietary supplement.” 15
  • EPA and DHA. While nuts, seeds, and other plant-based foods provide the essential omega-3 fatty acid alpha-linolenic acid (ALA), it’s critical to distinguish between ALA and EPA and DHA, two long-chain omega-3 fatty acids primarily found in marine sources, particularly cold-water fatty fish. There are many reasons why it’s important to make sure we’re getting enough EPA and DHA. And if you’re not eating fatty fish or supplementing with fish/krill oil, then an excellent plant-based source is microagal oil, which is what fish eat and how they acquire high levels of EPA and DHA.
  • Protein. Although there are many plant-based foods that provide protein, there are a couple issues plant-eaters face. First, protein quality (which refers to the balance of amino acids and the digestibility of the protein) of plant foods is generally quite poor compared to animal-based foods. Secondly, it can be challenging to consume an optimal amount of protein—particularly for athletes, active people, and older folks whose protein needs may be higher—without overconsuming calories, carbohydrates, and/or fats. Generally speaking, a plant-based protein supplement is foundational for virtually everyone navigating a vegetarian lifestyle.

**Please note that this is not a rub on vegetarianism. Virtually any diet that excludes large categories or groups of foods is bound to yield insufficient amounts of certain essential nutrients and other important health-promoting compounds. **

#2: Junk food is still junk food. Like I said before, just because something is vegan doesn’t necessarily = healthy. While vegetarianism is supposed to be based on whole-plant-based foods, that is not inherently true, especially as companies capitalize on the rise in popularity of the vegan and vegetarian lifestyles.

Even though French fries may seem a bit hyperbolic, there’s no shortage of examples of vegan junk food and less-healthy plant foods, such as:

  • Fruit juices
  • Refined grains (such as breakfast cereals, white bread, English muffins, bagels, rolls, muffins, biscuits, pancakes, waffles, crackers, pasta)
  • Processed potatoes, French fries, potato chips, corn chips, and pretzels
  • Sugar-sweetened beverages
  • Sweets and desserts (like candy bars, chocolates, cookies, brownies, donuts, cake, sweet rolls, pies, jams, jellies, preserves)

Basically, any so-called food made with refined grains and/or added sugar fits into the bucket of less-healthy plant food. The above serve as several examples, but like I mentioned, food manufacturers are catching on to the popularity of vegetarianism. So, you’re bound to see many, many more packaged food products marketed as vegan, vegetarian, plant-based, etc. Beware of them, and keep in mind the healthiest vegetarian approach is one that emphasizes whole plant-based foods and discourages refined and processed food products.

While whole-food plant-based diets have been associated with a range of better health outcomes, the opposite is true of diets higher in less-healthy plant foods. For example, in a study published in the Journal of the American College of Cardiology, researchers from the Department of Nutrition at the Harvard T.H. Chan School of Public Health in Boston sought to better understand the association between the degree of plant-based diet quality on coronary heart disease (CHD). 2

To do so, they created a general plant-based diet index (PDI) as well as a healthful PDI (hPDI)—where healthy plant foods (such as whole grains, fruits, vegetables, nuts, seeds, legumes, coffee, and tea) received positive scores—and an unhealthful PDI (uPDI)—where less-healthy plant foods (like juices, sweetened beverages, refined grains, potato products, and sweets) received positive scores.

Not surprisingly, they found a higher intake of healthy plant-based foods (higher hPDI) was associated with a substantially lower risk of CHD. On the other hand, the researchers found CHD was significantly elevated with a higher uPDI (higher intake of less-healthy plant foods). In fact, the risk of CHD was, on average, 32% higher for men and women who had a higher uPDI.

What’s more, in a study published in the journal PLoS Medicine, this same group of researchers found a higher hPDI score (i.e., a plant-based diet that emphasized healthy plant foods) reduced the risk of type 2 diabetes by 34%. On the flipside, a higher uPDI score was associated with a 16% increased diabetes risk. 16

Basically, there are severe negative consequences associated with a junk-food diet—vegetarian or not. In other words, vegetarianism isn’t just about what you’re not eating. The healthfulness of vegetarianism is also determined by what you are eating. Just because you’re not eating meat doesn’t make you any healthier if you’re eating a bunch of junk—plant-based or not.

#3: No one-size-fits-all diet. If there’s one thing we’ve learned over the years, it’s that we’ve yet to find the “perfect” diet for everyone, all the time. While vegetarianism represents an extremely broad dietary pattern, and plant-based diets can be tailored to fit an individual’s needs and preferences, a vegetarian lifestyle may not be the golden ticket for everyone.

For instance, despite a pretty overwhelming body of research suggesting dietary fibers are quite healthful (and most people aren’t consuming enough), some folks’ digestive tracts may not be particularly amenable to copious amounts of various fibers and other indigestible compounds (e.g., certain polyphenols) inherent to a whole-food plant-based diet.

For example, insoluble fibers seem to be particularly problematic for some folks, leading to digestive distress. Meanwhile, certain fermentable fibers (even otherwise healthy prebiotics) result in gas production, which may lead to abdominal distention, bloating, and discomfort.

Folks who have recurring digestive-related complaints may find a fiber-heavy plant-based diet—even though it’s quite “healthy” on paper—does more harm than good. Often, these folks have an imbalance of gut bacteria (for example, bacterial overgrowth or simply too much opportunistic bacteria), and they do better with a lower load of fermentable substrates (at least for a brief period of time).

Of course, it may be difficult for many individuals to completely give up some or all animal foods and go “all-in” with a vegetarian lifestyle. That’s okay. If you ask me, I don’t personally think it’s necessary to be completely vegan. However, most people can benefit from gradually increasing their consumption of whole plant-based foods while decreasing their consumption of processed animal foods/products.

The evidence clearly shows the lines are not black and white when it comes to the health benefits of eating more plant-based foods. In other words, you don’t have to be full-time hardcore vegan to experience the potential health benefits of vegetarianism.

Rather, shifting toward a diet that emphasizes healthy plant-based foods, reduces the consumption of animal foods, and limits the amount of less-healthy plant foods is probably the sweet spot.

Is the Vegetarian Diet Healthy: A Recap

In my mind, there’s little question that the vegetarian diet is healthy, particularly when it emphasizes whole-plant-based foods. In fact, I think most people would be well served to increase their consumption of whole-plant-based foods while minimizing their intake of refined, processed foods (both less-healthy plant foods and animal-based foods).

However, vegetarianism isn’t just about what you’re not eating. The healthfulness of vegetarianism is also determined by what you are eating. Just because you’re not eating meat doesn’t make you any healthier if you’re eating a bunch of junk—plant-based or not.

Metabolic Age Quiz

Keep in mind that doesn’t mean full-time vegetarianism is healthier than a semi-vegetarian or omnivorous approach. However, the overwhelming majority of folks could stand to shift further toward the whole-food plant-based diet end of the spectrum.

Heck, over a decade ago, author and journalist Michael Pollan provided “the short answer to the supposedly incredibly complicated and confusing question of what we humans should eat in order to be maximally healthy” when he said, “Eat food. Not too much. Mostly plants.” 17

No dietary dogma there. That’s a pretty darn solid guideline, and I’d qualify food by saying “real food.” And just to piggyback on that, I would add that when/if you do consume animal-based foods (which I do), choose products from animals that are raised humanely, sustainably, and if possible, locally. For example, choose organic meat and dairy from grass-fed, pasture-raised cows that are humanely treated (and not treated with artificial growth hormones and antibiotics). Choose eggs and poultry from pasture-raised sources. Choose wild, sustainably sourced fish.

Although there’s a long-standing stigma with nutrition-based pyramids, I shall leave you with this nifty Food Triangle that offers a novel way to conceptualize food in a way that eliminates the traditional groups of foods based on macronutrients, which doesn’t offer enough specificity when it comes to types and sources of proteins, carbohydrates, and fats. 18,19 The Food Triangle also organizes whole foods based on energy density, and it conveniently separates foods based on other nutritional components (such as phytonutrients and fibers) important to health span and longevity.

References

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