Welcome Green Monsters! We're your online guide to making conscious choices that help people, animals and the planet.
Download food monster: the biggest, baddest, yummiest vegan food app!


We’re constantly bombarded with the message that we might die if we don’t eat enough protein, but our country isn’t sick or dying from protein deficiency- we’re sick and dying from disease. Our protein intake as a country is also extremely high, with meat, dairy, eggs, toxic-filled whey protein powders, fish, pork, poultry, and highly-processed meat and cheese products ranking as some of the most popular in our culture today. And it’s pretty easy, considering that the media promotes a high protein diet and a McDonald’s is located on every corner. Then there’s the supermarket where an abundance of processed lunch meats exist and over 30 varieties of cheese, with likely over 50 choosings of yogurt. Protein, protein, protein- it surrounds us everywhere we go. While protein intake is an important part of the human diet, perhaps we need to take a step back and assess the increase in animal protein in this country with with our increased rate of disease that goes along with it.

The Man Behind The Plant-Based Anti-Cancer Movement

Dr. T. Colin Campbell, author of The China Study, has spent 50 years researching the correlation between diet and cancer. He’s dedicated his life to showing people how cancer prevention begins with what we put on our forks, and what we don’t. Dr. Campbell recently gave a speech in Hawaii where he proposed that our high protein intake isn’t just unnecessary, it’s also a huge problem when it comes to increased cancer risks. Dr. Campbell (who actually grew up on a dairy farm) has spent limitless energy investigating and proving how a plant-based diet has the ability to prevent and even treat cancer. He’s linked casein intake to multiple types of cancer, and meat consumption to prostate and colon cancer.

But he hasn’t stopped there. Regardless that Colin has faced extreme criticism from the medical world and the entire food industry, Colin hasn’t backed down on his beliefs or his investment in research studies to get to the bottom of America’s cancer problem. Dr. Campbell has been a long-time believer that a diet high in animal protein intake is a leading cause of cancer – and he’s got the research to back it up.

What Does the Research Say?

Meat and dairy have specifically been linked to increased cancer risks, and giving up dairy is one of the best things a person can do to decrease their risks of developing cancer or experiencing cancer cell growth. In 1968, Campbell detailed a studied that was the first widely accepted study to be published regarding the intake of animal protein and increased cancer risk. Researchers found that the animals in the study who ate a diet made up of 20 percent protein had the strongest tumor growth rate, while animals only fed five percent protein had absolutely no tumor growth whatsoever. Over three weeks, animals were fed the same rates of protein and those who ate a diet of 20 percent experienced massive, fast tumor growth, while those who at only five percent protein still had no tumor growth whatsoever. For the last three weeks of the study, researchers removed protein from the animals’ diet that were eating 20 percent protein and their tumor growths completely stopped.

The unique part about the study was that an increase in plant-based proteins intake showed no increase in tumor growth rate. This is clear evidence that animal protein contributes to cancer and plant-based proteins do not. Colin concludes that increased protein consumption is like flipping the cancer switch on, while eating minimal amounts turns the switch back off.

But Don’t We Need Protein?

While we do need protein, perhaps we don’t need so much as we might think. The Center for Disease Control and Physician’s Committee for Responsible Medicine both agree we are getting plenty of protein and that protein deficiency is not a problem in our society, especially in comparison to the cancer problem we have. The Physician’s Committee for Responsible Medicine (PCRM) even says that we actually get too much protein, around double of what we really need. They advise using the Recommended Dietary Allowance (RDA) protein formula, which is : 0.8 grams per kilogram of body weight for the average adult. To find out your average individual need, multiply your body weight in pounds by your recommended protein intake in grams.

How to Plant-Based Proteins Play a Part?

Plant-based proteins should be sourced, according to Dr. Campbell and to PCRM, from whole, plant-based foods such as leafy greens, vegetables, beans, legumes, nuts, seeds, and grains- not processed products or animal products. According to Dr. Campbell and to PCRM, eating a diet that includes a serving of legumes, greens, vegetables and grains at each meal, will provide plenty of protein, along with wholesome, plant-based nutrients.

More on Dr. Campbell and Cancer Prevention

Dr. Campbell has funded the nonprofit organization, T. Colin Campbell Center for Nutrition Studies, based in Ithaca, NY at Cornell University, which provides comprehensive education for individuals interested in plant-based  nutrition. The school offers a Certificate in Plant Based Nutrition and has become a nationally-recognized nutrition education program. Campbell also has a documentary coming out called Plant Pure Nation, due in early 2015, which will be produced by his son, Nelson Campbell.

“Diet can be used to prevent and reverse cancer just like it prevents and reverses heart disease,” said Dr. Campbell. “A diet high in animal protein increases the amount of carcinogens going to the cells. It increases the enzyme MFO (mixed function oxidase) that causes increased carcinogenic activity.”

Image Source: Gage Skidmore/Flickr

Want to read more posts like this? Sign up for our newsletter below!​

Browse through some recent posts below:

What a Lamb in a Sweater Can Teach Us About How We See Cats and Dogs

Sweet Rosie Will Change the Way You See Farm Animals

This Single Photo Reveals the Tragic Fate of Captive Elephants

This Single Photo Exposes the Full Horror and Tragedy Behind Elephant Captivity

Victory! 3 Lions Rescued From Circus and Brought Home to African Sanctuary (PHOTOS)

Victory! 3 Lions Rescued From Circus and Brought Home to African Bush

Caring Mama Cat Adopts a Gaggle of Ducklings! (PHOTOS)

Meet the Sweet Cat Who Adopted Adorable Ducklings

Disclosure: One Green Planet accepts advertising, sponsorship, affiliate links and other forms of compensation, which may or may not influence the advertising content, topics or articles written on this site. Click here for more information.

397 comments on “Are We Eating Too Much Protein? A Scientist Makes the Connection Between Protein and Cancer”

Click to add comment
Michelle Yipe
1 Years Ago

I don't know about cancer but I do know that our bodies produce some protein and we need just to intake just a little bit. Too much protein can cause health problems and kill you. As for cancer the latest is every one born since 2010 will get cancer. But there are several cures for cancer and many ways not to get it. it's all up to you.

Bj Anderson
1 Years Ago

yes we are...as a matter of fact

Jerrilyn Henson
1 Years Ago

Dr. Campbell would know... too much protein is bad for our kidneys among a lot of other things...

Kelly Deckelbaum
1 Years Ago

Jack Deckelbaum

Marion Jeanne Wesson Gaffney
1 Years Ago

Everything seems to give u cancer. Fat, protein, carbs., sugar.... The list goes on. Just starve and get it over with.

Dawn Marie Peters
27 Nov 2015

Actually I don't believe there has been one study to show that whole fruits or veggies have ever been linked to cancer as long as they haven't been covered in pesticides and herbicides.

Kathleen Polletta
27 Nov 2015

And remember that you must research/check out who, how, how long the study lasted and what goal they were headed. There is a lot more to "a study" than meets the eye and is published.

The 3Week Diet
1 Years Ago

Good news: if you want to lose weight quickly and have a perfect body visit our page to know more about 3Week Diet ;) <3

Daljeet Singh
1 Years Ago

Now you could accuse me of being a "brainwashed pharmashill" all you want but I'm not particularly convinced of this. However the following was known already for quite a long time: “even at 20 percent of diet calories, soy and wheat protein did not induce pre-cancer development the way that animal proteins did..." The problem here is something unfortunately only someone with a biological background would know :S There are a lot of things you need to take into account i.e. what else was contained with that protein, what kind of protein was it, was the food chain taken into account?

Kat Milacek
28 Nov 2015

Read the book: The China Study if you haven't already. Lots of good epidemiological research and information on plant-based diet across many cultures

Heather Thrapp
1 Years Ago

Tom Beall

Craig Williams
1 Years Ago

Both it would seem.

1 Years Ago

The EPIC study shows that cancer is not about what you eat


I\'m not thrilled by any study that shows differences of 20% either way. If animal protein causes cancer it should not need massive studies to show it up. Most dietary studies don\'t give you clear information. Disease is about stress, exercise, deficiency, diabetes, .... yada yada. Diet is not really going to save you.

21 Jun 2015

The study you cited proves that diet controls cancer. It says that people who don\'t consume animal flesh have lower rates of cancer than people who do, and it further says that since those people are still consuming dairy and eggs, that their rates of cancer are still high. What it doesn\'t concern is what Dr. Campbell proved, which is that that people who don\'t consume flesh, dairy, OR eggs have the lowest rates of cancer of all.

If you really want to learn about health, read these links:

A basic simple explanation of what Animal Rights means in relation to Veganism:

All the info you will ever need on whether a non-Vegan diet is optimally healthy or not:

Massive amounts of info on how humans exploiting nonhumans is destroying this planet:

Subscribe to our Newsletter

Follow us on

Do Not Show This Again


Submit to OneGreenPlanet

Terms & Conditions ×