I have noticed a significant interest in my breast cancer communities about the effectiveness of the keto diet in managing future risk of cancer and weight loss. Full disclosure, I oppose most drastic, structured “diets” as they seem to contribute to “yo-yo” dieting. A lifetime of fighting my own weight has shown me that a stable, sensible diet is more important than any diet fad. But I try to be open-minded.
So I did some research into the keto diet, using what I love most, information and opinions from cancer centers and research institutions. I realize that there are many, many other sources, blogs, and diet advocates out there. But I am looking strictly at the scientific efficacy of the diet, so I am sticking to the facts about the diet itself.
This is what I have found.
What is the keto diet? It is a low carb diet. You eat more protein and fat while cutting out most carbs and sugar. Once you starve your body of carbs, it is forced to burn fat. This causes the creation of “ketones”. According to MD Anderson, “Ketones are a type of acid made by your liver and then sent into your bloodstream. Too many ketones can led to dehydration and alter the chemical balance of your blood”. Due to the various side effects, I personally think that any attempt at this diet needs to be under the care of a doctor and qualified dietician.
Does it cure cancer?
My biggest concern is the claims that the keto diet someone can inherently reduce risk of cancer (or cure it, as you will find in various parts of the internet). I’m going to go out on a limb here and say that many fit, healthy people get cancer. Some of these people were on low-carb diets. They include athletes and follow healthy diets. Cancer doesn’t discriminate, and a specific diet in and of itself does not appear to me to stop cancer. Cancer goes where it wants.
It’s not just my opinion though.
According to MD Anderson, “No single food can cure cancer, but some research has shown a link between the keto diet and slowed growth of some types of tumors in mice. A few studies in humans with certain types of brain tumors have also shown promise. On the contrary, a very low-fat diet has been found to reduce risk of recurrence for certain types of breast cancer.”
So is the focus on such a low-carb option useful? Does it make more sense to focus on ingredients, not so much the carb number? Or a careful balance of carbs and fats? I tend to think so, but these are really the questions that the keto-curious need to ask themselves.
I was unable to find any actual studies that advocate for keto as a cure for cancer. There has been some limited evidence of the usefulness of a keto diet in improving the success of certain cancer drugs (Cornell in particular has worked in this area). But this is not a cure in and of itself, and the drugs that have shown promise with the diet are not used in breast cancer treatment. Hopefully, this is evolving research.
But can I lose weight?
The other point that is always stressed is the role of keto in weight loss. Obesity is a risk factor in breast cancer recurrence, and a diet that keeps this is in check definitely has value. As far as the keto diet, I think the part where your body is forced to burn fat is what is appealing. And most of the sources I have reviewed note that as a weight loss alternative, keto is certainly effective. But is it healthy? I think it depends on what you do with it. Here are a few insights I have gathered:
• In order to be successful, any diet initiative needs to be sustainable over the long term. The keto diet is overly restrictive. Doctors note that the keto diet is very hard to maintain, and often leads to yo-yo dieting in the future.
According to Memorial Sloan Kettering, “Ultimately, when it comes to diet, it depends on what works and is achievable for a particular person. Changing dietary behavior may be more effective than following a specific diet. In other words, if you can eat a healthy diet that is not overly restrictive, such as the American Cancer Society diet, this may be the most beneficial approach in the long run.”
For me, I know a drastically low carb diet is not realistic for me. I need a balance of all nutrients in order to control cravings. And I have learned that short-term diet solutions make my situation worse in the long run.
• One of the things that has most appalled me about the keto diet is the reliance on high amounts of protein and fat. One commentary from Harvard that I read noted, “Because it lacks carbohydrates, a ketogenic diet is rich in proteins and fats. It typically includes plenty of meats, eggs, processed meats, sausages, cheeses, fish, nuts, butter, oils, seeds, and fibrous vegetables… One of the main criticisms of this diet is that many people tend to eat too much protein and poor-quality fats from processed foods, with very few fruits and vegetables.”
MD Anderson agrees. ”In addition, diets high in fat are associated with heart disease and obesity. Many keto diet-safe foods, like red meat, can increase your cancer risk”.
The normal justification that I hear from people on the diet is “Oh, I don’t eat all that fatty meat, cheese, and dairy.” Which is good. Because I know others who do, and the diet has already failed for them. But the point here is that focusing on lean proteins and quality fats is definitely the way to go. But it’s not necessary to go to the extent of the keto diet. Any sensible lifestyle change would focus on exactly the same thing, while allowing high quality carbs to assist with energy and sugar cravings. If you don’t have that issue, that’s great, but so many of us do. We have to think long-term.
I always find great nutrition advice from Dana Farber, and the keto diet is no exception. They note, “For patients interested in the keto diet, a more moderate approach may be advised. There is evidence that cutting down on the amount of refined carbohydrates in typical diets and increasing the amount of healthy fats consumed can be beneficial to one’s overall health. Before altering your diet in any way, you should always consult with your doctor and registered dietitian”.
Harvard summarizes it well, “A balanced, unprocessed diet, rich in very colorful fruits and vegetables, lean meats, fish, whole grains, nuts, seeds, olive oil, and lots of water seems to have the best evidence for a long, healthier, vibrant life.”
And that is why I currently do not follow the keto diet. I have included links below for reference. And as always, you should always discuss your diet and lifestyle with your doctors. What is right for me may not be right for you.
Please visit us at www.driventosurvive.org for more resources in your breast cancer journey!
References:
https://www.mdanderson.org/publications/cancerwise/the-keto-diet-and-cancer–what-patients-should-know.h00-159223356.html
https://www.mskcc.org/blog/keto-claims-can-diet-be-form-cancer-therapy
https://moffitt.org/take-charge/take-charge-story-archive/can-a-keto-diet-help-cancer-treatment/
http://news.cornell.edu/stories/2018/07/low-carb-high-fat-diet-may-boost-targeted-cancer-therapy