While I was standing in the check-out line in the grocery store, a magazine touting the keto diet caught my eye. I didn’t bite (pun intended), and here’s why.
Dr. Greger at Nutrition Facts.org.
If you are reading my health blog for the first time, I will tell you Dr. Greger heads the list of my trusted resources. He is a physician who researches the research. It doesn’t take long surfing the internet before you find “research” galore proving or debunking the same topic. Unless I have the time or expertise to delve into published scientific papers, I will turn to the physician who has made analyzing this stuff his life’s work.
The Keto Diet
As a cancer survivor, I’m vested in leaving that experience in the rear view mirror. Given the rising cancer diagnoses in America, mostly due to our lifestyle choices—about 85% vs genetic causation—I thought preventing cancer or its return would interest others as well.
Here are the highlights from Dr. Greger’s video, “Is Keto an effective cancer fighting diet?” at
He explains that “sugar” or carbohydrates, is the body’s favorite fuel, especially for the brain. (Of course it’s best if this sugar comes from whole grains and not highly processed sugar, which carries its own load of harm to our health. But that’s for another blog.) Proponents of the keto diet avoid carbs, and favor using fat to fuel the body. Fat breaks down into ketones, and as the ketone level rises, the body goes into “ketosis.” We know ketosis is a serious condition, but apparently this is supposed to be a different form of ketosis. Preferred sources of saturated fat are animal—steaks, chops, etc. Unfortunately, this high fat content does not cross the blood-brain barrier well, so now neither carbs nor fat fuels the brain in sufficient amounts. Besides, saturated fat is not good for the cardio-vascular system and also can promote colo-rectal cancer.
Merriam-Webster’s definition of blood-brain barrier: a naturally occurring barrier created by the modification of brain capillaries (as by reduction in fenestration and formation of tight cell-to-cell contacts) that prevents many substances from leaving the blood and crossing the capillary walls into the brain tissues.
According to Greger, to eat enough to fuel the brain without ingesting many carbs and natural sugars in fruits and veggies, the body would need to break down 172-259 grams of body protein. But that comes from lean body mass, not body fat. Your bathroom scale doesn’t know the difference and will show a loss, but it’s a dangerous loss.
It’s not that I will die if I eat a steak dinner, and I occasionally enjoy a typical dinner with meat. But I’ve discovered it’s not that great and I happily return to my whole food, plant based diet the next day.
What Foods Feeds or Fight Cancer?
I constantly hear that cancer feeds on sugar. But cancers are made up of cells and all my cells, even the healthy ones, feed on carbohydrates. Cancer cells also feed on ketones, which some studies have shown fuel tumor growth and metastasis. The villain is saturated fat that is found in abundance in meat and dairy.
Recommendations from the American Cancer Society and the American Society of Clinical Oncology Breast Cancer Survivorship Care Guidelines (that’s a mouthful!) include a diet high in fruits, vegetables, whole grains and legumes, low in saturated fat and limited alcohol consumption.
In a book touting the Keto diet, the author’s preference for meats and other fatty foods over plant- based whole foods because of the sugar content shocked me. By the way, these “sugars” eaten in whole food form do not have a high glycemic level because they do not shoot up the glucose level like a candy bar would. It’s like the writer was terrified of eating more than two beans! Talk about malnutrition, about avoiding the very foods that fight cancer on several levels.
Physician’s Committee for Responsible Medicine
This group is my other “go-to” source.
How many oncologists tell their patients to eat fruits, vegetables, whole grains, and legumes? Either they have no clue (“Eat whatever you want. Nothing you did caused this.”), or they wait for the patient to think to ask them about diet. Neither is responsible medicine. Fortunately, because of organizations like the PCRM, more physicians are recommending diet as a weapon in the war against cancer.
They state a plant based diet will reduce cancer. Just keeping meat and dairy intake to a minimum and “beefing up’ on your fruits and veggies, etc. helps. For example, pigments in colorful foods (beta-carotene in sweet potatoes or the lycopene in tomatoes) fight cancer cells. High fiber found only in plants helps remove excess hormones that could lead to breast, prostate, or colo-rectal cancers. Even the World Health Organization declares that grilling meats, including chicken and fish, releases carcinogens, as well as red and processed meats like bacon and hotdogs.
If you take anything from this blog, read or print out the fact sheet at PCRM’s site “Foods For Cancer Prevention.”
Bottom Line to Fight Cancer
Keto no, plant-based yes
Bravo, Sue! Remind me when I see you to relate the tale of a keto-based rapid weight loss diet that our own St. Joe’s espoused back in the early 90’s. It was not pretty, I can assure you!
I want to send your article to a good friend who has been dabbling in diet plans for years, including keto. My diet is very similar to yours and I’m sticking to it! Thank you for this insight!
Now the trick is to find a restaurant that caters to people like us. I wonder how others have navigated that. You order a salad thinking you’re following your diet, but it’s dressing is full of cheap oil with lots of saturated fat. One time, I brought my own salad dressing in a snap top empty pill container and ordered the salad plain. What a bother!