Do Vegans or Pescatarians Live Longer? Science Weighs In

For decades, people have embraced plant-based diets for ethical, environmental, and health reasons. But perhaps one of the most compelling questions driving dietary choices is this: Do vegans or pescatarians live longer? As longevity and quality of life become central concerns in modern wellness, understanding the health impacts of different diets is more important than ever. This article explores the scientific evidence behind vegan and pescatarian lifestyles, compares their long-term health outcomes, and sheds light on which may offer a longer, healthier life.

Understanding the Diets: Vegan vs. Pescatarian

Before diving into longevity, it’s critical to clearly define what it means to be vegan or pescatarian. Both diets emphasize plant-based foods, but their inclusion (or exclusion) of animal products differs dramatically.

What Is a Vegan Diet?

A vegan diet excludes all animal products. This includes meat, poultry, fish, dairy, eggs, and even honey. Vegans rely entirely on fruits, vegetables, grains, legumes, nuts, and seeds for nutrition. Many adopt this lifestyle not just for health, but for animal rights and environmental sustainability.

Vegans require thoughtful planning to ensure they receive adequate nutrients, particularly:

• Vitamin B12
• Vitamin D
• Omega-3 fatty acids (EPA and DHA)
• Iron
• Zinc
• Calcium

Deficiencies in these nutrients, if not properly managed, can lead to health complications over time.

What Is a Pescatarian Diet?

A pescatarian diet includes plant-based foods plus fish and seafood, while excluding other meats like beef, pork, and poultry. Dairy and eggs are typically included, unless otherwise specified. This hybrid approach offers flexibility, combining the heart-healthy benefits of fish with the fiber-rich advantages of plant foods.

Pescatarians benefit from the natural provision of:

• Omega-3 fatty acids (EPA and DHA) from fatty fish
• High-quality protein
• Iodine
• Vitamin B12
• Selenium

These nutrients are harder to obtain on a strict vegan diet without supplementation.

The Role of Diet in Longevity

Diet is one of the most influential factors in determining lifespan. Numerous studies have shown that long-term dietary habits affect the risk of chronic diseases such as heart disease, cancer, type 2 diabetes, and neurodegenerative conditions—leading contributors to premature death.

A diet associated with longevity typically features:

Both vegan and pescatarian diets align well with these principles, but their nuanced differences may tip the balance in one direction or another when considering lifespan.

Scientific Evidence on Vegan Longevity

Numerous long-term studies have examined the health outcomes of vegans, with promising results.

The Adventist Health Study

One of the most comprehensive studies on plant-based diets is the Adventist Health Study-2 (AHS-2), which followed over 96,000 Seventh-day Adventists in the U.S. and Canada. This population is ideal for dietary research because many follow vegetarian or vegan diets, and their lifestyles often include lower rates of smoking and alcohol use.

Key findings include:

• Vegans had a 15% lower risk of all-cause mortality compared to non-vegetarians.
• Vegan men showed a particularly strong advantage, with a reduction in heart disease mortality by up to 55%.
• Vegans also had lower BMIs and significantly reduced rates of hypertension and type 2 diabetes.

These findings suggest that a vegan diet supports not only longer life but also healthier aging.

Cancer and Disease Prevention

The AHS-2 and other studies, such as the Oxford Vegetarian Study, have also reported that vegans have:

• Lower rates of colorectal, prostate, and breast cancers.
• Better insulin sensitivity, reducing risk of metabolic syndrome.
• Naturally lower LDL cholesterol and blood pressure.

This is likely due to the high fiber, low saturated fat, and rich phytonutrient content of plant-based diets.

Potential Downsides of Veganism

However, vegan diets aren’t without risks. Poorly planned vegan diets can lead to deficiencies in:

• Vitamin B12: Critical for nerve function and blood cell formation. Deficiency can cause anemia and neurological damage.
• Omega-3 fatty acids (DHA and EPA): Although plant sources like flaxseeds provide ALA, conversion to EPA and DHA in the body is inefficient.
• Iron and zinc: Plant-based forms (non-heme iron, phytate-bound zinc) are less bioavailable.

One 2020 systematic review in BMJ Nutrition, Prevention & Health highlighted that while vegans have lower disease risks, those who don’t properly supplement or plan their diets may face elevated risks of bone fractures and certain nutrient deficiencies over time.

Therefore, while the data supports improved longevity for well-nourished vegans, success depends heavily on attention to nutrition.

What About Pescatarian Longevity?

Pescatarian diets present an interesting middle ground—plant-based with added seafood benefits. Let’s examine the science behind this eating pattern.

Lower Mortality and Heart Health

Multiple large-scale studies have shown that including fish in a plant-based diet dramatically improves outcomes. The Nurses’ Health Study, which followed over 100,000 women for decades, found that:

• Pescatarians had a 20% lower risk of dying from heart disease than non-fish eaters.
• Eating fish twice a week was associated with a reduction in all-cause mortality by approximately 17%.
• Pescatarians had longer telomeres—a marker of cellular aging—compared to omnivores and even some vegetarians.

Fish, especially fatty varieties like salmon, mackerel, and sardines, are rich in omega-3 fatty acids. These healthy fats reduce inflammation, improve vascular health, and are linked to lower rates of sudden cardiac death.

Neuroprotection and Cognitive Aging

The Framingham Heart Study and others have shown that higher fish consumption correlates with better brain health. Pescatarians may experience:

• Slower rates of cognitive decline
• Reduced risk of Alzheimer’s disease and dementia
• Optimal levels of DHA, essential for neuron function

These benefits can contribute not only to living longer but to living more fully in later years.

Potential Risks of the Pescatarian Diet

Despite its advantages, a pescatarian diet isn’t risk-free. Key concerns include:

• Mercury and heavy metal exposure: Large predatory fish like tuna and swordfish can contain high levels of mercury, which is neurotoxic, especially in high quantities or during pregnancy.
• Microplastics and pollutants: Increasing evidence shows ocean pollution affects seafood quality.
• Overconsumption of salted or processed fish: Canned, smoked, or cured seafood may be high in sodium, linked to hypertension.

However, choosing smaller, sustainably sourced fish (like sardines, anchovies, and trout) can largely mitigate these risks.

Comparing Lifespan: Vegan vs. Pescatarian

Now, the central question: who lives longer—vegans or pescatarians?

Direct Comparative Studies

A pivotal analysis from the Adventist Health Study-2 directly compared different dietary patterns and found that:

Interestingly, despite strong health benefits, pescatarians showed the greatest reduction in mortality among all dietary groups.

This suggests that the inclusion of fish—especially omega-3-rich varieties—may provide a crucial boost toward longevity.

Explaining the Pescatarian Advantage

Why might pescatarians live longer than vegans, on average?

Better Omega-3 Status

While flaxseeds and chia seeds offer ALA (a type of omega-3), the conversion to EPA and DHA—the forms most beneficial for heart and brain—is inefficient in humans (often below 10%). Vegans who don’t supplement with algae-based DHA may have suboptimal levels.

In contrast, pescatarians receive direct DHA and EPA from fish, which is linked to:

• Reduced arterial plaque buildup
• Lower triglycerides
• Improved mood and brain function

Iodine and Selenium

Fish and seafood are rich in iodine, essential for thyroid function. Vegans often have very low iodine intake unless they consume iodized salt or seaweed, which can be inconsistent and sometimes excessive.

Selenium, another trace mineral found abundantly in fish, supports immune function and antioxidant defense. While plant foods contain selenium, soil content varies widely by region.

Protein Quality and Satiety

While plant proteins are excellent, fish provides a complete protein with all essential amino acids in ideal ratios. This supports muscle preservation, immune health, and overall vitality—especially important with aging.

Bone Health Considerations

A 2019 study in the European Journal of Clinical Nutrition reported that vegans had a 43% higher risk of bone fractures than non-vegans. This may be linked to lower calcium intake and possibly lower vitamin D status in some individuals.

Pescatarians typically consume more calcium (from dairy) and vitamin D (from fish and sunlight), further supporting bone strength.

Key Factors That Influence Longevity Beyond Diet

It’s essential to remember that longevity isn’t determined solely by diet. Lifestyle factors often play as significant—sometimes more significant—roles.

Exercise and Physical Activity

Both vegans and pescatarians tend to be more physically active than the general population. Regular exercise builds cardiovascular endurance, improves insulin sensitivity, and maintains bone density.

Sleep and Stress Management

Chronic stress and poor sleep elevate cortisol, increase inflammation, and impair metabolic health. Dieters who pair plant-based eating with mindfulness, meditation, or yoga often show better outcomes.

Social and Economic Factors

Access to healthcare, education, socioeconomic stability, and even social support networks influence lifespan. The populations studied (like Adventists) often benefit from tight-knit communities, which may amplify health benefits beyond diet alone.

Smoking and Alcohol Use

These habits significantly impact longevity. Many vegans and pescatarians avoid or limit smoking and alcohol, further tilting the odds in their favor.

Making an Informed Choice for Longevity

So, do vegans or pescatarians live longer? The data suggests that pescatarians may have a slight edge in lifespan, largely due to the heart and brain benefits of fish. However, a well-planned vegan diet remains one of the healthiest choices available.

The key takeaway is not about dogma—it’s about optimization.

For Vegans: Prioritize Supplementation and Planning

To maximize longevity on a vegan diet:

• Supplement with B12 (at least 2.4 mcg daily).
• Use algae-based omega-3 supplements to ensure adequate DHA and EPA.
• Consume fortified foods or supplements for vitamin D, especially in winter.
• Include calcium-rich foods (fortified plant milks, tofu, leafy greens) and consider a calcium supplement if intake is low.

With these steps, a vegan diet can be just as robust—or even more beneficial—than a pescatarian one.

For Pescatarians: Choose Wisely

To minimize risks in a pescatarian diet:

• Eat fish 2–3 times per week, focusing on low-mercury options like salmon, sardines, trout, and mackerel.
• Avoid high-mercury fish such as shark, swordfish, and king mackerel.
• Balance seafood with a strong foundation of vegetables, legumes, whole grains, and nuts.
• Limit processed or canned fish with high sodium content.

Real-Life Examples of Longevity in Plant-Based Diets

It’s worth noting that some of the longest-living populations—known as Blue Zones—include both pescatarians and omnivores who eat fish, but rarely meat.

Nuoro, Sardinia (Italy)

Men in this region live significantly longer than average. Their diet is predominantly plant-based, with whole grains, beans, and vegetables, supplemented by small amounts of fish, goat milk, and cheese.

Okinawa, Japan

Okinawans famously have one of the world’s highest concentrations of centenarians. Their traditional diet includes sweet potatoes, bitter melon, soy, and small servings of fish—particularly sardines and tofu-based seafood dishes.

These populations demonstrate that moderate fish intake within a largely plant-based diet is associated with exceptional longevity.

Conclusion: It’s About Whole Patterns, Not Just Labels

The debate over whether vegans or pescatarians live longer isn’t a zero-sum game. Both diets promote longevity when thoughtfully followed. But current evidence suggests that the pescatarian diet has a slight advantage in reducing mortality, largely due to optimal omega-3 intake, superior protein quality, and better support for bone and brain health.

However, a well-supplemented vegan diet can close the gap—and may even offer ethical and environmental benefits that some prioritize.

Ultimately, longevity isn’t just about one food or nutrient. It’s about the overall dietary pattern, combined with lifestyle choices like physical activity, sleep, stress management, and community engagement.

Whether you choose a vegan or pescatarian lifestyle, the best diet for longevity is one that:

• Is rich in whole, minimally processed plant foods
• Meets all micronutrient needs
• Supports sustainable habits for life
• Brings joy and satisfaction

So, rather than focusing solely on labels, focus on building a long, vibrant life—one nourishing meal at a time.

What does current science say about the lifespan of vegans compared to pescatarians?

Scientific studies have found that both vegans and pescatarians tend to have longer life expectancies compared to individuals following standard omnivorous diets. A key contributor to this increased longevity is the lower incidence of chronic diseases such as heart disease, type 2 diabetes, and certain cancers. Vegans, who consume no animal products, often have lower cholesterol levels, reduced blood pressure, and healthier body mass indexes (BMIs), all of which are protective against major causes of premature death. Research from large population studies, including the Adventist Health Study-2, indicates that vegans may have a mortality rate up to 15% lower than non-vegetarians.

Pescatarians, who include fish and seafood in their otherwise plant-based diets, show similarly impressive health benefits. Fish is a rich source of omega-3 fatty acids, which are known for their anti-inflammatory properties and cardiovascular benefits. Some studies suggest that pescatarians may have slightly lower mortality rates than strict vegans due to improved intake of essential nutrients like vitamin B12, iodine, and high-quality protein, which are harder to obtain on a vegan diet. However, the differences in longevity are often modest, and both dietary patterns are associated with significantly improved health outcomes over time.

How does fish consumption impact the health of pescatarians?

Fish consumption is a defining feature of the pescatarian diet and offers numerous health advantages. Fatty fish such as salmon, mackerel, and sardines are rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two types of omega-3 fatty acids that support heart and brain health. Regular intake of these nutrients has been linked to reduced triglyceride levels, lower blood pressure, and decreased risk of arrhythmias. Additionally, fish provides high-quality protein, vitamin D, and selenium, all of which contribute to immune function and metabolic health.

Despite these benefits, the impact of fish on health can be influenced by the type and preparation method. Grilled or baked fish is generally associated with positive outcomes, whereas fried fish or heavily processed seafood can negate benefits due to added trans fats and sodium. Concerns also exist around contaminants like mercury and polychlorinated biphenyls (PCBs), especially in large predatory fish. However, for most pescatarians who consume fish in moderation and focus on low-mercury options, the health benefits outweigh the risks, supporting their place in a longevity-promoting diet.

What nutritional challenges do vegans face that might affect longevity?

Vegans must carefully plan their diets to avoid deficiencies in several critical nutrients, including vitamin B12, iron, omega-3 fatty acids, calcium, vitamin D, and iodine. Vitamin B12, found almost exclusively in animal products, is essential for nerve function and red blood cell formation. Deficiency can lead to anemia and neurological issues, which may impair long-term health if unaddressed. Similarly, plant-based iron (non-heme iron) is less bioavailable than animal-based iron, increasing the risk of iron-deficiency anemia, particularly in women.

While these challenges exist, they are manageable through fortified foods and supplementation. For example, B12 supplements and fortified nutritional yeast can effectively prevent deficiency. Algae-based omega-3 supplements provide an alternative source of DHA and EPA without relying on fish. With proper attention to nutrition, vegans can meet all dietary requirements and maintain excellent health. In fact, those who follow well-planned vegan diets often have lower rates of obesity and metabolic syndrome, which positively influence lifespan when nutritional gaps are closed.

Can a pescatarian diet reduce the risk of heart disease?

Yes, a pescatarian diet is strongly associated with a reduced risk of heart disease, one of the leading causes of death worldwide. The inclusion of fish—especially oily fish—provides a steady intake of omega-3 fatty acids, which help lower inflammation, reduce arterial plaque buildup, and improve overall cardiovascular function. Studies have consistently shown that individuals who eat fish regularly have lower rates of heart attacks, strokes, and cardiovascular mortality compared to those who consume little or no fish.

Additionally, pescatarians typically consume more plant-based foods like whole grains, fruits, vegetables, legumes, and nuts—components known to support heart health. This combination of nutrient-dense, fiber-rich foods and healthy fats creates a synergistic effect that benefits blood pressure, cholesterol levels, and vascular health. Long-term observational data suggests that pescatarians may enjoy some of the lowest rates of heart disease among dietary groups, making this eating pattern particularly favorable for cardiovascular longevity.

Are there specific longevity benefits from a plant-based diet?

Plant-based diets, including both vegan and pescatarian patterns, are rich in antioxidants, fiber, phytonutrients, and healthy fats—all of which contribute to reduced oxidative stress and inflammation. These factors play a crucial role in slowing aging at the cellular level and lowering the risk of age-related diseases. High fiber intake, common in plant-based eaters, supports a healthy gut microbiome, which recent research links to improved immune function, metabolic regulation, and even brain health.

Fruits, vegetables, legumes, and whole grains also naturally contain fewer saturated fats and no dietary cholesterol, reducing the burden on the cardiovascular system. Moreover, plant-based diets are typically lower in energy density, which supports healthy weight management over time. Population studies, such as those conducted on “Blue Zones” where people live exceptionally long lives, show that diets centered on plants are a common denominator. This consistent evidence highlights the powerful role of plant-based eating in promoting human longevity.

Is there a difference in cancer risk between vegans and pescatarians?

Both vegans and pescatarians tend to have lower overall cancer risks compared to omnivores, largely due to higher consumption of protective plant foods and lower intake of processed and red meats, which the World Health Organization has classified as carcinogenic. Vegans may experience particular benefits in reducing the risk of colorectal, prostate, and breast cancers, likely due to high fiber intake, abundant phytochemicals, and lower levels of circulating hormones linked to cancer development.

Pescatarians also benefit from reduced cancer risk, though the inclusion of fish introduces a nuanced perspective. While some compounds in fish have anti-inflammatory and anti-cancer properties, concerns linger about environmental contaminants such as mercury and PCBs, which may increase cancer risk at high exposure levels. However, moderate consumption of low-mercury fish does not appear to elevate risk and may provide protective effects. Overall, both groups outperform meat-eaters in cancer prevention, with subtle differences depending on specific food choices and overall dietary quality.

How important is diet quality within vegan and pescatarian lifestyles for longevity?

Diet quality is a critical factor in determining how much either a vegan or pescatarian diet contributes to longer life. Simply avoiding animal products or eating fish does not guarantee health benefits if the overall diet is rich in processed foods, refined sugars, and unhealthy fats. For example, a vegan who consumes mostly fries, sugary snacks, and processed mock meats may not achieve the same longevity benefits as one who eats whole grains, legumes, nuts, and abundant vegetables.

Similarly, a pescatarian who relies heavily on fried fish, refined carbohydrates, and processed foods may miss out on the cardiovascular and metabolic advantages associated with this diet. Studies emphasize that the protective effects of both dietary patterns are most pronounced when they center on whole, minimally processed foods. Therefore, longevity is not solely about being vegan or pescatarian but about the quality, variety, and balance of the foods consumed within those frameworks.