Science-Based Reasons for a Plant-Based Diet (environment, animals, humans)

If there was a miracle cure, that could help mitigate climate changeend animal suffers and prevent millions of human deaths caused by health diseases, would you want to know about it? This urgently needed solution for today’s main challenges is a PLANT-BASED DIET.
We could stop here. That’s it.
But of course, we also want to explain to you, based on scientific studies and reviews, why and how a plant-based diet is a solution for so many problems at one time!

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To whom we address this blog post

In the following, we talk especially to people from nations that boast an abundance of dietary options.
We do also address middle-income countries, which are unfortunately largely affected by the standard western diet, including fast food. However, NOT included are people who suffer severe food shortages and are forced to eat whatever is available.

First Reason: Climate change and destruction of the environment

According to a high scientific consensus, we are facing a climate crisis!
Still, most people (including us at the moment!) live a lifestyle, which requires far too many resources than what would be sustainable. Thereby the nutrition is one of the single biggest lifestyle factors affecting climate change!
In fact, agriculture is one of the critical human activities that impact our climate and ecosystems. (17)

graphic of the water footprint in liters per person per day in different countries
Water Footprint of consumption –liters per day per person (36)

The reduction in meat intake (especially beef) has the most significant impact on the Water Footprint reduction. (34) E.g., one beef steak 3500 liters, one beef burger patty requires 2626 liters of water, one liter of milk about 1000 liters, and one egg 200 liters, whereas a baked potato requires 108 liters. (35)

Regional distribution of emissions from livestock
Regional distribution of emissions from livestock. Source (37)

The plant-based Solution

The scientific evidence claims: the higher consumption of animal-based foods is associated with the highest environmental impacts. In contrast, increased consumption of plant-based foods is associated with the lowest environmental impact. [4, 9-11, 13, 15, 16] Thus, plant foods generally have a significantly lower environmental impact and are implicated with far less water, land, and energy use compared to animal agriculture. [4,15,16] Indeed, even the least sustainable plant food is still significantly more sustainable than the best environmentally performing animal food. [4]

Environmental effects per serving of food produced The Lancet EAT Report (13)
Environmental effects per serving of food produced The Lancet EAT Report (13)

Globally, there is enough cropland to feed 9 billion people in 2050! But only if 40% of all crops produced today for feeding animals were used directly for human consumption. (19) In conclusion, the simple environmental truth is that we have to eat less meat – far less – and make a change towards a plant-based diet!

Extinction of the marine life


It’s not a secret that the oceans are already nearly completely exploited, hence life in the sea is threatened with extinction. To clarify, 80% of fisheries are already overfished or collapsing. (27) Fish from aquaculture namely is fed with fish from the ocean in the form of fishmeal, fish oil, plants, and animal trimmings. About 6 million metric tons of pelagic fish are harvested every year. An additional 2 million tons (only 30%) is generated from the scraps produced when fish are processed for human consumption. (44) The volume of global fish production amounted to 178.8 million metric tons in 2018, up from 148.1 million metric tons in 2010. (28) In other words, this makes up nearly 490.000 tons each day!

Destruction of the ocean ground

Bottom-trawling is a commercial way of fishing species like shrimp, grouper, and scallop. Thereby huge nets are pulled over the seafloor. Scientists say that the destruction caused by bottom-trawling is similar to that caused by clear-cutting old forests, only on a far grander scale. When first developed, bottom-trawling nets were limited to parts of the ocean that had a soft sediment floor because rocks and coral tore holes in the netting, allowing fish to escape. Nowadays, they have huge wheels, chains, or metal doors along their bottom edges. The heavy metal scrapes along the ocean floor and keeps the nets just off the bottom to prevent them from being torn.

Fishing nets with bycatch

Plastic pollution caused by Fishing

However, the problem lies not only in the overfishing and extinction of many species, but it’s also about the immense cause of plastic pollution through fishing nets. Scientists found that at least 46% of the plastic of the “Great Pacific Garbage Patch” comes from fishing nets. (26) Overall, an estimated 640,000 tonnes of fishing gear is left in our oceans each year! (29) Lost fishing gear pollutes the oceans and therefore is part of our food chain. We eat what the animals have eaten before.
Say what?!

Food for thought:
Would you really want to eat a whole bunch of microplastic with your fish or shrimp?

What can we do?

Ahead of the expected population growth, our planet is going to be subjected to, we need to produce more food than ever before. But to prevent a global climate collapse, a production with drastically fewer emissions than right now is indispensable! (14) Animal foods are significantly more resource-intensive (per calorie and gram of protein) than plant foods. (2-4) Therefore, the cheapest, fastest, and most effective action that can be taken at a global scale to mitigate climate change is a dietary shift towards consuming more plant-based foods and less meat in particular and other animal-based foods. (5-8)


In short, we will list the 4 most important environmental reasons to make a shift towards a plant-based diet:

  • animal agriculture is one of the leading causes of global warming
  • energy and water usage for animal products is way higher than for plant-based foods
  • food production of animal products is the primary cause of deforestation
  • oceans are hugely overfished and polluted with chemicals and microplastic

A plant-based diet, with the highest amount of local and seasonal ingredients possible, is the most climate- and environmentally-friendly diet!


Compared to all other diets, a plant-based (and vegan) diet does not put the human species above all other species. Therefore it respects animals in the same way and does not support “speciesism”. For decades humans have been taught that different animal species belong to a different position in the hierarchy of animate beings. Some are to protect, and some are to exploit and slaughter.

Food for thought:
Why do you feel sympathy with a cat and a turtle but not with a chicken and a squid?
Speciesism is only possible because people don’t (want to) accept the cruel reality and sad truth behind their favorite products.


Animals like cattle, pigs, and chicken are kept in mass stocks for food production. Every burger, every piece of fried chicken, every strip of bacon is directly linked to suffering and slaughter.
But what about grass-fed or free-range products?
In our opinion, these are clever tricks of the marketing industry to give us consumers a good conscience. In the end, all animals (even grass-fed or free-range) are brutally slaughtered. Terms like “all-natural“, “farm-fresh” and so on are even more misguiding. The reality of a farm-fresh pig steak does not really differ to a conventionally farmed pig, as monitoring and controls are not reliable and, therefore, can be totally neglected.

How about concerning businesses that obligate themselves to very high standards and hold certificates?
In our opinion, even those can not guarantee a “happy life” for the animals, and the fact is they have no “humane” killing methods neither.
(We are still wondering how one can label killing as “humane”.) 

Food for thought: 
Is it okay for you, to let animals suffer and be slaughtered for a 10-20 minute “enjoyment”?


No matter of argument, the conventional egg industry with mass production in “battery” cages uses horrible methods to maximize the profit.

Let’s talk about eggs which are labeled… get a coffee and hold strong… organic, pasture-raised, free-range, cage-free, vegetarian-fed, humanely-raised (or Certified Humane), natural, hormone-free, fertile, antibiotic-free, animal welfare approved, cruelty-free or farm-fresh, etc. god damn, the industry invented countless marketing terms to sell their eggs.

So now that we have listed apparent “positive” arguments of the industry, here is why we still shouldn’t buy eggs (in the supermarket): male chicks.
Male chicks are worthless to the egg industry! Therefore every year, millions of them are suffocated and thrown into high-speed grinders, called “macerators,” while they are still alive or alternatively gassed.

If you don’t want to cut out eggs from your diet completely, please make sure you support someone who makes an effort for all newborn chickens, not only the female.


The dairy industry is comparable to the egg industry. Again, there is no debate about the conventional industry (Do NOT support!). And again, there is the apparently “good” fraction of the dairy industry (you already know all the marketing terms now).


It’s still questioned if fish can feel pain or not. Researchers now have found that fish do have the capacity for pain perception and suffering. (47) Sports fishing and catch and release fishing are ridiculously gross murder. Researchers at the Oklahoma Department of Wildlife Conservation found that as many as 43% of fish released after being caught died within six days. And it’s not only the suffering of fish and accidentally caught animals, but it’s also a problem of fishing gear.

Lost fishing nets, so-called “Ghost nets“, float int the ocean for decades if they are not found and pulled out. Sadly they keep killing marine life for no reason. Fish, whales, sharks, dolphins, turtles, seals, and more get tangled up. Consequently, these animals either slowly drown or suffer from cuts and strangulation for the rest of their lives.

World Animal Protection estimates that entanglement in ghost gear kills at least 136,000 seals, sea lions, and large whales every year. (29)


In short, we list the most relevant animal welfare reasons to go plant-based:

  • protecting all animal rights and stop speciesism
  • fighting wildlife extinction (on land and sea)
  • take indirect harm and killing into account

Third Reason: HEALTH

The Lancet EAT commission describes a universal healthy reference diet as a diet that primarily consists of vegetables, fruits, whole grains, legumes, and nuts, that includes a low to moderate amount of seafood and poultry and includes as least as possible red meat, processed meat, added sugar, and refined grains. (13) The commission estimated that adopting such a healthy diet could prevent more than 11.5 million deaths or 23.6% of total deaths among adults per year. (13)


People who eat red meat have higher risks of cardiovascular disease, diabetes, and some cancers than people who eat plant sources of protein. The intake of red meat appears to be linearly related to total mortality and risks of other health outcomes in populations that have consumed it for many years. Therefore the optimal intake might be 0 g/day, especially if replaced by plant sources of protein. (13) The World Health Organization stated that 50g of processed meat a day – less than two slices of baconincreased the chance of developing colorectal cancer by 18%. (40)

Summarizing, one can say that the current meat consumption is grossly unsustainable from both a health and environmental perspective.

Dairy products

The body needs protein and calcium to build healthy bones. But the problem is: As your body digests protein, acids are released into the bloodstream and neutralized by drawing calcium from the bones. Dairy products have not only a lot of calcium but also a lot of protein and saturated fat. Hence, consuming a lot of milk products or following a high-protein diet for a long time may weaken your bones.

The World Health Organization stated that regions with low intake of dairy foods have lower fracture rates than areas with high dairy consumption. (30) Milk and other dairy products are next to the meat, the top sources of saturated fat in the standard western diet. Diets high in fat, especially saturated fat, and cholesterol increase the risk of heart disease.

Additionally, whole milk intake in men contributes to elevated prostate cancer mortality risk. (43) Men who drank more than two glasses of milk a day were almost twice as likely to develop advanced prostate cancer as those who didn’t drink milk at all. (42) Nowadays, it’s still highly discussed if the cow’s milk growth hormones affect the hormone-producing organs in humans.

High levels of galactose, a sugar released by the digestion of lactose in milk, have been studied as being possibly damaging to the ovaries and leading to ovarian cancer. However, some researchers have hypothesized that modern industrial milk production practices have changed milk’s hormone composition in ways that could increase the risk of ovarian and other hormone-related cancers. (45) According to that, we should change the source of calcium apparently – from dairy products to plant-based sources.


It’s no doubt, eggs are a good source of protein. BUT, and this is a huge “but”, it’s always the question with which package of other nutrients it comes. The overall health score of an egg decreases drastically, because of its high amount of cholesterol and saturated fats, which contributes to arteriosclerosis.

Among US adults, higher consumption of dietary cholesterol or eggs is significantly associated with a higher risk of incident CVD and all-cause mortality. The more dietary cholesterol or eggs you eat, the more your risk of CVD and all-cause mortality will increase. (48)

Food for thought:
Several studies want to convince us that dietary cholesterol is not harmful. Many of those studies are sponsored by the egg industry or an egg-producing company though.

Fish and Poultry

According to the Lancet, a healthy diet includes low to moderate seafood and poultry.

So why do we recommend no seafood and no poultry at all?
We need some essential fatty acids and protein. Fish and chicken are natural sources for these nutrients. This is the reason why they are recommended for a healthy diet.
BUT we have many equivalent plant-based alternatives to get the same essential nutrients.

What speaks against fish and poultry related to health?
On the one hand, many fish are super high in non-essential fats, ocean fish contain rising mounts of plastic, and aquaculture requires high amounts of antibiotics and other pharmaceuticals.

Food for thought:
So why keep eating products which may contain either microplastic or antibiotics or is high in unnecessary fats when we know there are equivalent plant-based alternatives without any of these health risks?

Good plant-based alternatives for essential fatty acids are avocado, walnuts, flax/ chia/ hemp/ sesame seeds, leafy greens, and seaweed (spirulina). On the other hand, poultry is linked to illnesses like infertility in women. For instance, half a chicken breast a day increases the risk of infertility risk of more than 50% for women. (38) The fact is, poultry is not as unhealthy as red meat, but it also doesn’t bring any benefits, compared to high-quality plant-based sources. Equivalent sources of protein are beans, tofu/ tempeh, peas, quinoa, couscous, lentils, leafy greens, seeds, and soy milk.

The paradox of animal foods

Against common sense, animal products deliver no essential nutrients, which can not be replaced by a plant-based diet, except Vitamin B12. Only a supplementation and/or fortification with Vitamin B12 is recommended, especially but not exclusively for vegan/ plant-based people. (18)

Read more about Vitamin B12 supplementation in our whole-foods plant-based diet for beginners’ guide.

For decades, we have been taught that we need animal products for our health – milk for bones, meat for muscles, and fish for the heart. Paradoxically it’s absolutely the other way around: many animal products are correlated to major human diseases! Alarming 66% of the emerging diseases in humans have animal origins, and one or two new diseases emerge every year. (19)

Top ten causes of deaths

The tables which are shown below display important differences in causes of death between low-income and high-income countries.

WHO The top 10 causes of death (22)
Top 10 causes of deaths low-income countries 2016
WHO The top 10 causes of death (22)

Noncommunicable diseases (NCD) are referred to as “lifestyle” diseases. Almost all of these diseases are preventable. The most common causes for NCD include drug consumption, physical inactivity, and, last but not least, the standard western diet. In high-income countries, the intake of processed foods, and animal products like red meat and dairy products is way higher than in low-income countries. Additionally, the average daily physical activity is less, and the drug consumption like alcohol and cigarettes is higher. (41) These lifestyle habits remain in a shift of the most prevalent causes of death. At least 7 of 10 leading causes of death in high-income countries (apart of 4, 5, and 6), can be prevented and partially reversed with a whole-foods plant-based diet.

Overall mortality and cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of death in the United States. High saturated and trans fat intake (which elevates LDL like saturated fat) combined is associated with an 8–13% higher mortality. (46)

In contrast, reducing saturated fat and replacing it with complex carbohydrates will reduce total mortality. (46) Replacing saturated fats with polyunsaturated fatty acids (PUFA), monounsaturated fatty acids (MUFA), or high-quality carbohydrates will lower chronic heart diseases (CHD events). (46)


There is a general consensus that a whole foods plant-based diet is highly beneficial for preventing and treating type 2 diabetes. (25) A study examined vegans having half the rate of type 2 diabetes compared to people on a standard western diet. (21)

Another great study of plant-based eating patterns (with 4.1 million person-years of follow up) in the US showed that those participants who were most adherents to a healthful plant-based diet compared to those least adherents had a 34% lower risk of developing diabetes. These associations were independent of body mass index and other diabetes risk factors. (23)


Among different plant-based diets (i.e., Lacto-Ovo vegetarian, lactovegetarian, and vegan), populations following vegan diets had the lowest cholesterol concentrations. It also found that plant-based diets are associated with up to a 35% reduction in serum LDL cholesterol, whereas interventions allowing small amounts of lean meat demonstrated less dramatic reductions in total cholesterol and LDL levels. (24)

3 health-related reasons to switch to a (whole-foods) plant-based diet

  • fight major human diseases
  • achieve a better quality of life (vitality and longevity)
  • lose weight in a healthy and effective way

The bottom line

At the end of the day, a well-planned whole-foods plant-based diet is not only a great option in nutritional regards – but it can also yield meaningful benefits to our planetary health at a time in which climate change threatens the persistence of our and many other species. (39)

Indeed, the bottom line is that there is a diet that is good for you, good for the animals and good for the planet: a whole-foods plant-based diet.

Read more about plant-based nutrition


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