Somewhere along the way, eating plants became complicated.
For most of human history, it wasn’t. You ate from the garden, gathered eggs, kept a milk cow or a few goats, and maybe had a chicken on Sunday. That was the pattern for rural agrarian families across America and much of the world. Plants were just food.
Then the 20th century happened. We moved from the countryside into the cities and suburbs, stopped growing our own food, and let Big Food take over. Freezers arrived, and you could have meat every day of the week. Processing food became big business. Convenience won. And vegetables? Big Food didn’t do vegetables well, and frankly, the produce section had fresh but limited, local varieties of produce. The American diet became meat, potatoes, and whatever came in a box.
Thirty years ago, if you said you didn’t eat meat, people looked at you funny. You were a hippie, a New Age follower, a Hindu, or a Seventh-day Adventist. That was about it.
Since then, things have shifted dramatically. Plant-based eating has grown, matured, and gone mainstream. Los Angeles is full of juice bars and wellness shots. Meatless Monday is a thing. There are plant-based options for nearly everything, and enough variations to fill a glossary: vegan, vegetarian, lacto-ovo vegetarian, pescatarian, flexitarian, whole-food plant-based. And the question everybody wants answered is: which one is actually healthiest?
I’ve spent years looking at that question. I’ve done a detailed nutritional analysis comparing five dietary patterns side by side: Mediterranean, the Wahls Protocol, vegetarian, whole-food vegan, and the Hallelujah Diet. I know where the gaps are. I know what the blood work actually shows. And I know why some plant-based eaters get dramatically better outcomes than others.
Let’s dig into the science.
First, Let’s Get the Terms Straight
A vegetarian diet excludes meat, poultry, and sometimes fish, but typically includes dairy products and eggs. So a vegetarian might eat yogurt, cheese, milk, and eggs, which are all animal products, but avoids animal flesh.
A vegan diet goes further. It excludes all animal products: meat, poultry, fish, dairy, eggs, and usually honey. Everything on the plate comes from plants.
Within vegetarianism there are some sub-categories worth knowing. Lacto-vegetarians eat dairy but not eggs. Ovo-vegetarians eat eggs but not dairy. And lacto-ovo vegetarians eat both. Most vegetarians in Western countries fall into the lacto-ovo category. Pescatarians include fish, which technically makes them a subset of their own, but that’s a common gray area. For this article, when I say vegetarian, I mean lacto-ovo vegetarian, which is the standard definition.
Here is a side-by-side comparison of what each diet includes and excludes:
Vegetarian
Vegan
Meat & poultry
Excluded
Excluded
Fish & seafood
Usually excluded (may vary)
Excluded
Dairy (milk, cheese, yogurt)
Included
Excluded
Eggs
Included
Excluded
Honey
Included
Excluded
Plant foods
Included
Included
Typical B12 intake
Adequate from dairy/eggs
Requires supplementation
What the Long-Term Research Actually Shows
The most important data we have on plant-based diets comes from large prospective cohort studies. These aren’t short lab trials. These are studies that follow tens of thousands of people for decades and watch what happens to their health. Two of the most important are the EPIC-Oxford Study and the Adventist Health Studies.
The EPIC-Oxford Study
In 2022, Timothy Key and colleagues at the University of Oxford published a comprehensive update in the journal BMJ examining plant-based diets and long-term health using data from the EPIC-Oxford cohort, which includes over 65,000 participants. This is one of the most cited studies in this area.
Key and colleagues found that both vegetarians and vegans had significantly lower rates of heart disease, type 2 diabetes, and several cancers compared to meat eaters. Vegans showed the lowest BMI of any dietary group. Vegetarians also had favorable BMI and disease rates, sitting between vegans and meat eaters in most comparisons.
The one surprising finding in the Oxford work, which generated some press when it came out, was that vegetarians and vegans had a slightly elevated risk of hemorrhagic stroke compared to meat eaters. This needs context. The likely culprit isn’t the plant-based diet itself but B12 deficiency. Chronically low B12 raises homocysteine levels, and elevated homocysteine is a known risk factor for hemorrhagic stroke. This is correctable with supplementation and underscores why B12 is non-negotiable on a vegan diet and still important even on a vegetarian diet.
The Adventist Health Studies
The Adventist Health Study-2, conducted by researchers at Loma Linda University and following more than 90,000 Seventh-day Adventist men and women across North America, has produced some of the most detailed dietary comparisons in existence. Because Adventists span the full range of plant-based eating, from vegans to semi-vegetarians to non-vegetarians, all within a population with otherwise similar lifestyles, the data is particularly clean.
Across multiple analyses from this cohort, vegans consistently had the lowest BMI, the lowest risk of type 2 diabetes, and favorable outcomes for heart disease and some cancers compared to both vegetarians and omnivores.
And for blood cancer, specifically, the evidence is striking. As I covered in a recent article on multiple myeloma, Timothy Key and colleagues found that multiple myeloma in British vegetarians and vegans was dramatically lower than among meat eaters, with about a 77% decreased risk. That number is not a typo. The decrease in all cancers is not that dramatic, but for multiple myeloma, it really is.
The Key Nutritional Differences Between the Two Diets
Both diets can be done well or done poorly. But there are specific nutrients where the two diets genuinely diverge, and understanding these differences helps you make a more informed choice.
Vitamin B12
This is the most important nutritional distinction. B12 is produced by bacteria and is found naturally in animal products. Vegetarians who eat dairy and eggs generally get adequate B12 from those sources. Vegans do not, and B12 deficiency is a real and serious risk on a fully plant-based diet without supplementation.
Symptoms of B12 deficiency develop slowly, sometimes over years, and include fatigue, nerve damage, and cognitive problems. The stroke risk association mentioned above is part of this picture. If you are vegan, supplement with B12. This is not optional.
At Hallelujah Diet, we have been very clear about this ever since we did a study that was published in 2000, showing that vitamin B12 at the cellular level was an issue for vegans. We showed that, with some probiotics, it was possible to achieve adequate vitamin B12 levels, but not in everyone. Therefore, taking a B12 supplement or yearly testing is required.
Calcium
Vegetarians typically get calcium from dairy, so deficiency is less of a concern for them. Vegans need to be more intentional, drawing on dark leafy greens, tofu set with calcium sulfate, fortified plant milks, and almonds. That covers the basics. But the full picture of calcium and bone health is considerably more nuanced than a short paragraph can do justice to.
Here is the short version: more calcium does not automatically mean stronger bones. Meta-analyses of observational studies have found no reliable link between dietary calcium intake and hip fracture risk. Calcium supplements have a mixed record in clinical trials and are generally not the straightforward fix they are marketed as. More absorbable forms, used in lower doses, appear to work better than standard calcium carbonate.
What the research, including a study we conducted here at Hallelujah Diet, consistently points to is this: resistance exercise matters more for bone strength than calcium intake does. We tracked bone sonogram measurements in women following the Hallelujah Diet over three years and found that the type of exercise, specifically resistance training versus aerobic exercise only, was the strongest predictor of who maintained or improved bone strength. Diet quality and vitamin D were important supporting factors, but they were not the deciding variable.
Magnesium, vitamin K2, and vitamin D all play important supporting roles in bone metabolism that calcium alone cannot replicate. We have a full article on bone health, resistance exercise, and what actually protects you from fractures over the long term. Read it here.
Omega-3 Fatty Acids
Both vegetarians and vegans often fall short on EPA and DHA, the long-chain omega-3 fats most strongly associated with heart and brain health. ALA from flaxseed and walnuts is a precursor, but conversion to EPA and DHA in the body is limited and variable. A purified fish oil or an algae-based DHA supplement effectively closes this gap.
Iron and Zinc
Plant foods contain non-heme iron, which is less absorbable than the heme iron in meat. Consuming vitamin C-rich foods alongside iron-rich plant foods dramatically improves absorption. Zinc from grains and legumes is similarly affected by phytates, which bind minerals. Soaking legumes and eating fermented foods helps. Both vegetarians and vegans can maintain adequate iron and zinc, but it helps to know the strategies.
Protein
Protein is rarely the problem people think it is on plant-based diets. Beans, lentils, tofu, tempeh, nuts, seeds, and whole grains all contribute meaningful protein. Vegetarians have the added buffer of eggs and dairy. Vegans need to be a little more intentional, but a well-planned vegan diet easily meets protein needs.
Health Outcomes: A Head-to-Head Comparison
Looking across the research literature, here is how the two diets compare on key health outcomes:
Health Outcome
Vegetarian
Vegan
Heart disease risk
Reduced (20-30%)
Reduced (25-35%)
Type 2 diabetes risk
Reduced
Reduced (most)
Cancer risk
Reduced
Reduced
Body weight / BMI
Lower than omnivores
Lowest of any diet
Stroke risk
Slightly elevated if B12 deficient
Slightly elevated if B12 deficient
Multiple myeloma
Reduced
Reduced (77% lower)
B12 status
Generally adequate
Deficient without supplementation
A few things jump out from this table. First, both diets are genuinely protective against the major chronic diseases that kill most Americans. Second, vegan diets tend to produce slightly stronger outcomes on weight, diabetes, and cancer risk. Third, the stroke risk associated with both diets is almost certainly due to B12 and omega-3 deficiencies, not to plant foods themselves. Fix the deficiencies and you remove the risk.
The EPIC-Oxford Stroke Question: Let’s Actually Answer It
In 2020, a BBC article ran with the headline, ‘Are there health benefits to going vegan?’ and spent a significant portion of the piece discussing the EPIC-Oxford hemorrhagic stroke data. It raised fair questions about B12 and omega-3 on plant-based diets.
The stroke finding is real, but here is the important context. The participants who developed hemorrhagic stroke were likely chronically low in B12, which raises homocysteine, which damages blood vessel walls. This is not an argument against a vegan or vegetarian diet. It is an argument for making sure you supplement correctly.
A vegan diet with adequate B12, vitamin D, and omega-3 supplementation does not carry this elevated stroke risk. A vegan diet without supplementation might. The distinction matters. By supplementation, you take something that was a risk and turn it into a strength.
What About Weight Loss?
If weight management is one of your goals, plant-based diets offer a real advantage, and vegans tend to have the lowest body weight of any dietary group in the research.
The main reasons are caloric density and fiber. Plant foods, especially vegetables, legumes, and whole grains, deliver a lot of volume and fiber relative to their calorie content. This means you can eat satisfying amounts of food without taking in excess calories. Fiber also slows digestion and improves satiety signals.
Dairy and eggs, which vegetarians eat, are more calorically dense than most plant foods. This doesn’t make them harmful, but it does help explain why vegans consistently come in at lower BMI values in large population studies.
I covered the mechanisms of plant-based weight loss in detail in a recent in-depth post on plant-based diets for weight loss, including the role of insulin sensitivity and caloric density.
So Which Diet Is Actually Better for You?
Here is my honest analysis.
Both vegan and vegetarian diets are dramatically healthier than the standard American diet. If all you do is eliminate meat and eat mostly whole plant foods, you have already made one of the most meaningful health improvements available to you.
The research suggests that a well-planned vegan diet produces slightly better outcomes across most health markers, particularly for weight, diabetes prevention, and cancer risk. But ‘slightly better’ comes with a condition: it has to be well-planned. A vegan diet without B12, with poor protein sources, and heavy in processed convenience foods, is not necessarily superior to a thoughtful vegetarian diet.
For most people, the practical question isn’t vegan vs. vegetarian. The practical question is: how much closer can I get to a whole-food, plant-based diet while meeting my nutritional needs? That is the direction that matters, whatever your specific label.
The Hallelujah Diet Approach: More Plants, More Vegetables, Better Results
At Hallelujah Diet, we encourage a mostly raw vegan diet, with some cooked plant foods, strategic supplementation to fill the gaps, and an emphasis on vegetable volume that most plant-based eaters never come close to matching.
That last part is worth reflecting on for a moment, because it is where both vegetarian and vegan diets most commonly fall short.
Here is something I find genuinely surprising when I tell people about it. Many vegetarians and even vegans don’t actually eat enough vegetables to get the full protective benefit of a plant-based diet. I know that sounds counterintuitive. Vegetables are right there in the name. But the blood work tells a different story.
You can indirectly measure vegetable intake by examining plasma carotenoid levels. Carotenoids are the compounds that give carrots their orange color, leafy greens their deep hue, and tomatoes their red. Your body doesn’t make them. They have to come from food. So if carotenoids are low in someone’s blood, they haven’t been eating enough vegetables. That is just the way it is.
I published a review in the journal Nutrients in 2011 and created what I called the Carotenoid Health Index, looking at 62 studies linking plasma carotenoid levels to health outcomes, including cancer, heart disease, and diabetes. The data pointed to a clear threshold: to be in the genuinely protective range, you need total plasma carotenoids above 4 micromoles per liter. Below that, disease risk climbs. And above 95% of Americans sit well below even 1.5 micromoles per liter.
Then I looked at the Adventist Health Study-2, one of the largest plant-based cohorts in existence, and the results were sobering. In a 2019 analysis of plasma carotenoid levels across dietary groups, the vegans in the cohort averaged 1.86 micromoles per liter. Lacto-ovo vegetarians averaged 1.40. Non-vegetarians were at 1.17. The vegans were clearly doing better than the meat eaters. But against the 4 micromoles per liter threshold that the research points to as genuinely protective, every single group in this cohort fell short. The vegans weren’t even halfway there.
This helps explain something I have noticed for a long time. Published vegetarian studies often show less benefit than you would expect from a diet supposedly built around plant foods. The participants simply aren’t eating enough vegetables. Eliminating meat is not the same thing as eating a vegetable-rich diet. The power of a plant-based diet is in the plants.
The Hallelujah Diet is designed around actually eating that many vegetables. Think carrot and vegetable juice daily, blended salads, a large raw salad every day, and carotenoid-dense foods like yams, winter squash, bell peppers, and leafy greens making up a substantial portion of total calories. In an analysis I conducted at a 2012 Health Minister Reunion, 67 participants following the Hallelujah Diet had their plasma carotenoid levels tested. Sixty of those 67 were at or above 3 micromoles per liter. Forty-five of them, or 67%, were above the protective threshold of 4 micromoles per liter. That is a fundamentally different profile than what the Adventist Health Study-2 showed in its vegan participants.
Our perspective, then, is not just that plant-based eating is better than omnivorous eating. It’s that both vegetarians and vegans would get much better outcomes if they increased their vegetable intake substantially.
The supplements that matter most include vitamin B12, vitamin D3 with K2, a purified fish oil or algae-based DHA, and BarleyMax, our concentrated barley grass juice powder, which provides a dense source of vitamins, minerals, and enzymes from raw greens. These aren’t extras. They’re the foundation that makes a plant-based diet work at its highest level.
God has given us a self-healing body. When we remove the toxins and supply the nutrients we need to build a healthy body, it works well. That foundation was laid out in Genesis 1:29: fruits, vegetables, nuts, seeds, organic whole grains, and legumes. When we get close to that original pattern, self-healing and optimal health follow.
We recognize that we are not in the Garden of Eden, so we have to adapt to our environment and available foods. Nevertheless, the whole-foods, plant-based diet is where the research consistently points, and it is where we have built everything we do. We delight in the health that God has enabled us to enjoy when we follow His plan.
Hallelujah!
Frequently Asked Questions
Is a vegan diet healthier than a vegetarian diet?
In most large population studies, vegan diets produce slightly better outcomes for weight, diabetes prevention, and some cancers. But a vegan diet without adequate B12, vitamin D, and omega-3 supplementation can carry nutritional risks. A well-planned vegetarian diet can be equally healthy.
Do vegetarians live longer than vegans?
The ones who eat more vegetables probably live longer, whether vegetarian or vegan. The evidence doesn’t clearly favor one group over the other for overall longevity. Both vegetarians and vegans significantly outlive omnivores in most large cohort studies. What matters most is diet quality and appropriate supplementation.
What nutrients do vegans need to supplement?
Vitamin B12 is non-negotiable. Vitamin D, omega-3 fatty acids (EPA and DHA), and iodine are also commonly low. Some vegans also benefit from calcium, zinc, and iron supplementation depending on their dietary patterns.
What is the difference between a vegan and a plant-based diet?
Veganism is often defined by what you exclude (all animal products). A whole-food, plant-based diet is defined by what you include (unprocessed or minimally processed plant foods). A vegan eating processed convenience foods is technically vegan but not eating a whole-food plant-based diet. The two overlap significantly but aren’t identical.
Can a vegetarian get enough protein?
Yes, easily. Eggs, dairy, beans, lentils, tofu, tempeh, nuts, seeds, and whole grains all provide protein. Most vegetarians in Western countries meet or exceed protein recommendations without much effort.
Is a vegan diet safe for all life stages?
A well-planned vegan diet can be appropriate at all life stages, including pregnancy, infancy, and childhood, but it requires careful attention to B12, vitamin D, calcium, omega-3, and iron. Working with a knowledgeable healthcare provider is important for pregnant and breastfeeding women and young children on vegan diets.
What is the Hallelujah Diet?
The Hallelujah Diet is a mostly raw, whole-food, plant-based diet with a small amount of cooked plant foods and strategic supplementation. It draws on the biblical principle that whole plant foods are the optimal foundation for human health.
References
1. Key TJ, Papier K, Tong TYN. Plant-based diets and long-term health: findings from the EPIC-Oxford Study. Proceedings of the Nutrition Society. 2022;81(2):190-198. https://doi.org/10.1017/S0029665121003748
2. Orlich MJ, Singh PN, Sabate J, et al. Vegetarian dietary patterns and mortality in Adventist Health Study 2. JAMA Internal Medicine. 2013;173(13):1230-1238. https://doi.org/10.1001/jamainternmed.2013.6473
3. Tong TYN, Appleby PN, Bradbury KE, et al. Risks of ischaemic heart disease and stroke in meat eaters, fish eaters, and vegetarians over 18 years of follow-up: results from the prospective EPIC-Oxford study. BMJ. 2019;366:l4897. https://doi.org/10.1136/bmj.l4897
4. Key TJ, Appleby PN, Crowe FL, Bradbury KE, Schmidt JA, Travis RC. Cancer in British vegetarians: updated analyses of 4998 incident cancers in a cohort of 32,491 meat eaters, 8612 fish eaters, 18,298 vegetarians, and 2246 vegans. The American Journal of Clinical Nutrition. 2014;100 Suppl 1:378S-85S. https://doi.org/10.3945/ajcn.113.071266
5. Barnard ND, Levin SM, Yokoyama Y. A systematic review and meta-analysis of changes in body weight in clinical trials of vegetarian diets. Journal of the Academy of Nutrition and Dietetics. 2015;115(6):954-969. https://doi.org/10.1016/j.jand.2014.11.016
6. Willett W, Fontana L. Vegetarian and vegan diets: benefits and drawbacks. BMJ. 2023;383:e075200. https://doi.org/10.1093/eurheartj/ehad436
