The Medical Benefits of a Whole Foods, Plant-Based Diet


Written by: Ron Weiss, MD

According to the Centers for Disease Control (CDC), seven of the top 10 causes of death in 2010 were due to chronic diseases. Meanwhile, an extensive body of scientific research, published in top indexed medical journals like the JAMA Internal Medicine and American Journal of Cardiology, indicates that the standard American diet is predominantly responsible for these diseases and that a whole-foods, plant-based diet successfully prevents them. Medical schools nonetheless fail to teach about, and doctors fail to prescribe, a whole-foods, plant-based diet, with the result that millions of Americans have died, and continue to die, unnecessarily.

Seeing Is Believing

As a doctor trained in conventional medicine, I followed in the footsteps of prescribing pharmaceuticals and surgery, until 1992, when my own father was diagnosed with end-stage metastatic pancreatic cancer and was given between one and three months to live. I moved back home to take care of my father, immediately taking him to the premier medical institute for treating pancreatic cancer. The doctors there informed me that there was nothing they could do and also gave him no more than three months to live.

Following my gut, I headed to my local library and scoured the shelves. That’s where I came across information about macrobiotics, a whole foods, plant-based diet. Immediately working with two nutritionists, I put my father on a very strict version of this diet, and within one week, he sprang to life – getting out of bed, going off all his pain medications, and even heading back to the gym.

Three months after going on this diet, my father received a CT scan indicating that the tumor had shrunk by 33%. Nine months later, he received another CT scan, indicating that the tumor had shrunk by 50%. For end-stage metastatic pancreatic cancer, this kind of change was believed to be impossible. My father went on to live for another year and a half – working, exercising vigorously, and feeling better than he had for most his adult life.

The Personal Becomes Medical
My practice was molded by this experience, and nutrition became the foundational tool which I used to transform patients’ health. Those who adhered to the whole foods, plant-based diet I prescribed always did exponentially better than those who did not – ultimately leading me to build a wellness center on a 342 acre farm, where a whole foods, plant-based diet and lifestyle are at the heart of medicine.

Over the years, we have seen our patients reverse their chronic diseases, get off all their medications, and attain a healthy weight. A remarkable example is that of Joyce Barrier, a nurse practitioner who first came to our practice, as a patient, six months ago. Fifteen years prior, she inexplicably had been hit by an avalanche of life-threatening illnesses: acute toxic mega-colon, severely uncontrolled diabetes with peripheral neuropathy, asthma, Stevens Johnson Syndrome, inflammatory arthritis, fibromyalgia, pulmonary embolus, and hypertension. In a chain reaction, Joyce additionally became 160 pounds overweight.

Joyce was exhausted and in terrible pain, simply from climbing up the three steps to our medical office last March. Within six weeks of being on a whole foods, plant based diet, however, Joyce was off 24 medications, including the largest doses of insulin I had ever seen given to a patient, and as of a few weeks ago, Joyce was able to climb Mount Jo – a 2800 foot high mountain, with a 700 foot vertical.

Why It Works

There are different variations of a whole foods, plant-based diet. We prescribe a diet that consists of vegetables, fruits, starchy roots, whole grains, legumes, seeds, and nuts – all unrefined and minimally processed. In addition, we strongly advise that these foods are grown using environmentally-conscientious, organic farming methods – providing chemical-free, nutrient-dense food brought forth from a living soil.

There are several reasons why this diet works:

  • Phytonutrients
    Phytonutrients are plant molecules that activate the genes that fight disease in both plants and humans. Phytonutrients epigenetically bind to our DNA and positively change how our DNA expresses itself.
  • Fiber
    Fresh vegetables and fruits have huge amounts of fiber, which is mostly found in plant foods. Fiber is a critical fuel for many of the trillions of bacteria in our colon, the most densely-populated bacterial population on earth. These bacteria, known as our colonic microbiome, play an essential role in many of the internal systems that control our health.
  • Nutrition
    Plants are high in nutrition and low in calories. In addition, they lack the fat, sugar, and salt that lead to cravings – meaning that a plant-based diet leads to more stable eating habits and overall balance.
  • Purity
    Even when animals are raised in ethically and ecologically-sound ways, environmental toxins – which have been proven to cause all manner of chronic diseases – inevitably affect animals, through rain, air, and ocean water. These toxins all dissolve and get stored in fat. Whereas animals have ample fat for storing these toxins, plants have almost no fat. In addition, animal proteins provoke the manufacture of IGF1, a cancer-promoting hormone in our bodies, and animal proteins contain saturated fats that clog our arteries and promote diabetes. Although plants can have pesticides that can be passed on to the consumer, they are usually safer than most animal-based foods.

Getting Started
Depending on your personality, you might want to gradually increase your intake of whole, plant-based foods, while decreasing your intake of animal products, or you might want to dive in head-first and radically change your eating habits. Either way, remember these rules of thumb:

  • Given how most supermarkets are set up, the foods you want are likely on the outer edges of your local market, in the produce section and bulk foods aisle.
  • Emphasize green leafy vegetables, preferably raw, but cooked is good too. These are the most nutrient-dense vegetables, with the most medicinal benefits.
  • If you are taking medications, speak with your doctor about adjusting your dosage and eventually stopping your medications. This step is especially important if you are diving into the diet full-force, while taking blood pressure and/or diabetes medications. Given the powerful impact of plants in your system, your blood pressure and sugar levels may drop to dangerously low levels if the medications are not stopped in time.
  • If you are not already on a regular fitness program, start one now. Just walking a mile each day, for starters, will help you to sustain the healthy dietary changes you are undertaking, through a synergistic effect.


Ron Weiss MD, featured in top media including The New York Times and The Today Show, is a board-certified internist and Assistant Professor of Clinical Medicine at Rutgers New Jersey Medical School. The focus of his practice is the reversal and prevention of illness, using a whole foods, plant-based diet. To this end, he is the founder and Executive Director of Ethos Health, a farm-based healthcare system that connects human health to the natural world and fosters the fundamental connections that exist between all living things. For more information about Dr. Weiss and Ethos Health, visit