The ketogenic, or keto, diet has a lot of people talking, so we wanted to know what the hype was about – and what you should know about the hot diet.
We turned to Maria Petzel, senior clinical dietitian for the Pancreas Surgery Program at MD Anderson Cancer Center and an emeritus member of PanCAN’s Scientific and Medical Advisory Board, for answers.
PanCAN: What Is the Keto Diet?
Petzel: What many people are calling a keto diet lately is actually just a low-carb diet – more like Atkins or South Beach.
A true ketogenic diet, which is designed to achieve ketosis, must be extremely low in carbohydrates (about 5 – 10% of calories would come from carbs), controlled in protein and extremely high in fat.
In a low carb diet like the South Beach Diet or Atkins Diet, about 20 – 30% of calories come from carbs, and protein isn’t restricted.
In comparison, in a typical healthy diet, 45 – 65% of calories come from carbohydrates.
PanCAN: Does It Help You Lose Weight?
Petzel: The key to burning body fat is to eat fewer total calories (from any source) than you take in. For those losing weight on a ketogenic diet, it is because they have a deficit of calorie intake compared to calories burned. Often, being in ketosis will suppress the appetite, leading to lower total calorie intake in general.
PanCAN: Is It Safe?
Petzel: We do not know much about the long-term effects of the diet. There are concerns that it could be harmful to the heart and liver. The lack of fiber in the diet can lead to issues with constipation, which could exacerbate other conditions like diverticulitis.
Following a diet that basically cuts out an entire nutrient category – and therefore almost all grains, beans and lentils, most fruits, and some vegetables – can lead to vitamin and mineral deficiencies.
PanCAN: What Should Pancreatic Cancer Patients Know About Keto?
Petzel: If patients are on pancreatic enzyme replacement therapy, they will likely need to adjust their enzyme consumption to account for the increased dietary fat. Higher fat diets, like keto, can be harder to tolerate for some patients with pancreatic cancer, even with enzyme adjustment.
Also, the level of fat required for a true ketogenic diet has the potential to displace adequate protein intake.
Overall, the ketogenic diet poses a high risk of weight loss in patients, especially for those experiencing fat malabsorption.
The Bottom Line
“We recommend that adults eat a plant-based diet that includes a wide variety of plant proteins from nuts, seeds, beans and legumes, whole grains, non-starchy vegetables and fruit,” Petzel says. “We recommend adults get at least five servings of fruits and vegetables a day, along with plant proteins and whole grains adding up to at least 30 grams of fiber per day. Research supports this as the optimum diet for weight management and cancer risk reduction.”
And it’s important to talk to your doctor or dietitian before making changes to your diet – especially for pancreatic cancer patients.