The clinical use of ketogenic diets for epilepsy and cancer: what does the science say?
Is Keto an Effective Cancer-Fighting Diet?
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Blood sugar, also known as blood glucose, is the universal go-to fuel for the cells throughout our bodies. Our brain burns through a quarter-pound of sugar a day, its “preferred metabolic fuel.” Our body can break down proteins and make glucose from scratch, but most comes from our diet in the form of sugars and starches. If we stop eating carbohydrates, or stop eating altogether, most of our cells switch over to burning fat. But fat has difficulty getting through the blood-brain barrier. But our brain has a constant massive need for fuel, one organ accounting for up to half of our energy needs. Without it, the lights go out…permanently.
To make that much sugar from scratch, our body would need to break down about a half-pound of protein a day. That means we’d cannibalize ourselves to death within two weeks. But people can fast for months. The answer to the puzzle was discovered in 1967. Harvard researchers famously stuck catheters into the brains of obese subjects who had been fasting for over a month, and discovered that ketones had replaced glucose as the preferred fuel for the brain. Your liver can turn fat into ketones, which can then breach the blood-brain barrier and sustain your brain if you’re not getting enough carbohydrates. Switching fuels has such an effect on brain activity that it has been used to treat epilepsy since antiquity.
The prescription of fasting for the treatment of epileptic seizures dates back to Hippocrates. In the Bible, Jesus seems to have concurred. To this day, it’s unclear why switching from blood sugar to ketones as a primary fuel source has such a dampening effect on brain overactivity. How long can you fast, though? To prolong the fasting therapy, in 1921 a distinguished physician scientist at the Mayo Clinic suggested trying what he called a “ketogenic diet,” a high-fat diet designed to be so deficient in carbohydrates it could effectively mimic the fasting state. “[R]emarkable improvement” was noted the first time it was put to the test—efficacy that was later confirmed in randomized, controlled trials. Ketogenic diets started to fall out of favor in 1938 with the discovery of the anti-seizure drug that would become known as Dilantin, but ketogenic diets are still in use today as a third- or fourth-line treatment for drug-refractory epilepsy in children.
Oddly, the success of ketogenic diets against pediatric epilepsy seems to get conflated by “keto diet” proponents into suggesting a ketogenic diet is beneficial for everyone. But you know what else sometimes works for intractable epilepsy? Brain surgery. But I don’t hear people at the gym clamoring to get their skulls sawed open.
Since when do medical therapies translate into healthy lifestyle choices? Scrambling brain activity with electroshock therapy can be helpful in some cases of major depression, so what…pass the electrodes? Ketogenic diets are also being tested to see if they can slow the growth of certain brain tumors. Even if it works, you know what else can help slow cancer growth? Chemotherapy. So why go keto when you can just go chemo?
Promoters of ketogenic diets for cancer, paid for by so-called “ketone technology” companies that will send you salted caramel bone broth powder for a hundred bucks a pound. Or companies that market ketogenic meals report “extraordinary [anecdotal] responses” in some cancer patients, but more concrete evidence is simply lacking. Even the theoretical underpinnings may be questionable. A common refrain is that “cancer feeds on sugar.” But all cells feed on sugar. Advocating ketogenic diets for cancer is like saying Hitler breathed air, so let’s boycott oxygen.
Cancer can feed on ketones, too. Ketones have been found to fuel human breast cancer growth, and drive metastases in an experimental model—more than doubling tumor growth. Some have even speculated that may be why breast cancer often metastasizes to the liver, the main site of ketone production. If you drip ketones on breast cancer cells in a petri dish directly, the genes that get turned on and off make for a much more aggressive cancer, associated with a significantly lower five-year survival in breast cancer patients. Researchers are even considering designing ketone-blocking drugs to prevent further cancer growth by halting ketone production.
And think about what eating a ketogenic diet might entail. High animal fat intake may increase the mortality risk among breast cancer survivors, and potentially play a role in its development in the first place through oxidative stress, hormone disruption, or inflammation.
Men, too: “a strong association [has also been found] between saturated fat intake and prostate cancer progression.” Those in the top third of consumption of these kinds of fat-rich animal foods appeared to triple their risk of dying from prostate cancer. Not necessarily fat in general—no difference in breast cancer death rates based on total fat intake—but saturated fat intake may negatively impact breast cancer survival, a 50 percent increased risk of dying from breast cancer. There’s a reason the official American Cancer Society and American Society of Clinical Oncology Breast Cancer Survivorship Care Guidelines recommend a dietary pattern for breast cancer patients that’s essentially the opposite of a ketogenic diet: “high in vegetables, fruits, whole grains, and legumes, meaning beans, split peas, chickpeas and lentils, and low in saturated fats.”
So far, not a single clinical study has shown “a measurable benefit from a ketogenic diet for any human cancer.” There are currently at least a dozen trials underway, however, and the hope is that at least some cancer types will respond. Still, even then that wouldn’t serve as a basis for recommending ketogenic diets for the general population any more than recommending everyone go out and get radiation, surgery, and chemo for kicks.
Please consider volunteering to help out on the site.
- Sours HE, Frattali VP, Brand CD, et al. Sudden death associated with very low calorie weight reduction regimens. Am J Clin Nutr. 1981;34(4):453-61.
- Cahill GF. Survival in starvation. Am J Clin Nutr. 1998;68(1):1-2.
- Vanitallie TB, Nufert TH. Ketones: metabolism's ugly duckling. Nutr Rev. 2003;61(10):327-41.
- Owen OE, Morgan AP, Kemp HG, Sullivan JM, Herrera MG, Cahill GF. Brain metabolism during fasting. J Clin Invest. 1967;46(10):1589-95.
- Wheless JW. History of the ketogenic diet. Epilepsia. 2008;49 Suppl 8:3-5.
- Rho JM. How does the ketogenic diet induce anti-seizure effects?. Neurosci Lett. 2017;637:4-10.
- Castellini MA, Rea LD. The biochemistry of natural fasting at its limits. Experientia. 1992;48(6):575-82.
- Peterman MG. THE KETOGENIC DIET IN THE TREATMENT OF EPILEPSY, A PRELIMINARY REPORT. Am J Dis Child.1924;28(1):28-33.
- Levy RG, Cooper PN, Giri P. Ketogenic diet and other dietary treatments for epilepsy. Cochrane Database Syst Rev. 2012;(3):CD001903.
- Kossoff EH, Zupec-kania BA, Auvin S, et al. Optimal clinical management of children receiving dietary therapies for epilepsy: Updated recommendations of the International Ketogenic Diet Study Group. Epilepsia Open. 2018;3(2):175-192.
- Gershfeld N, Sultana P, Goldhamer A. A case of nonpharmacologic conservative management of suspected uncomplicated subacute appendicitis in an adult male. J Altern Complement Med. 2011;17(3):275-7.
- Dwivedi R, Ramanujam B, Chandra PS, et al. Surgery for Drug-Resistant Epilepsy in Children. N Engl J Med. 2017;377(17):1639-1647.
- Pope TM. Introduction: Voluntarily Stopping Eating and Drinking. Narrat Inq Bioeth. 2016;6(2):75-77.
- Martin-mcgill KJ, Srikandarajah N, Marson AG, Tudur smith C, Jenkinson MD. The role of ketogenic diets in the therapeutic management of adult and paediatric gliomas: a systematic review. CNS Oncol. 2018;7(2):CNS17.
- Klement RJ, Feinman RD, Gross EC, et al. Need for new review of article on ketogenic dietary regimes for cancer patients. Med Oncol. 2017;34(6):108.
- Gonder U. Article on ketogenic dietary regimes for cancer highly misleading. Med Oncol. 2017;34(6):109.
- Erickson N, Boscheri A, Linke B, Huebner J. Systematic review: isocaloric ketogenic dietary regimes for cancer patients. Med Oncol. 2017;34(5):72.
- Bonuccelli G, Tsirigos A, Whitaker-menezes D, et al. Ketones and lactate "fuel" tumor growth and metastasis: Evidence that epithelial cancer cells use oxidative mitochondrial metabolism. Cell Cycle. 2010;9(17):3506-14.
- Martinez-outschoorn UE, Prisco M, Ertel A, et al. Ketones and lactate increase cancer cell "stemness," driving recurrence, metastasis and poor clinical outcome in breast cancer: achieving personalized medicine via Metabolo-Genomics. Cell Cycle. 2011;10(8):1271-86.
- Martinez-outschoorn UE, Lin Z, Whitaker-menezes D, Howell A, Sotgia F, Lisanti MP. Ketone body utilization drives tumor growth and metastasis. Cell Cycle. 2012;11(21):3964-71.
- Brenner DR, Brockton NT, Kotsopoulos J, et al. Breast cancer survival among young women: a review of the role of modifiable lifestyle factors. Cancer Causes Control. 2016;27(4):459-72.
- Fradet Y, Meyer F, Bairati I, Shadmani R, Moore L. Dietary fat and prostate cancer progression and survival. Eur Urol. 1999;35(5-6):388-91.
- Brennan SF, Woodside JV, Lunny PM, Cardwell CR, Cantwell MM. Dietary fat and breast cancer mortality: A systematic review and meta-analysis. Crit Rev Food Sci Nutr. 2017;57(10):1999-2008.
- Runowicz CD, Leach CR, Henry NL, et al. American Cancer Society/American Society of Clinical Oncology Breast Cancer Survivorship Care Guideline. CA Cancer J Clin. 2016;66(1):43-73.
- Mayer A, Vaupel P, Struss HG, Giese A, Stockinger M, Schmidberger H. Response to commentary by Champ and Klement: Is a ketogenic diet the solution for the hyperglycemia problem in glioblastoma therapy?. Strahlenther Onkol. 2015;191(3):283-4.
- Wilder RM. The effect of ketonemia on the course of epilepsy. Mayo Clin Bull. 1921;2:307–8.
- Dong M, Zhu XM, Zheng W, et al. Electroconvulsive therapy for older adult patients with major depressive disorder: a systematic review of randomized controlled trials. Psychogeriatrics. 2018;18(6):468-475.
- Eenfeldt A. A ketogenic diet for beginners. Diet Doctor.
- Brosnan JT. Comments on metabolic needs for glucose and the role of gluconeogenesis. Eur J Clin Nutr. 1999;53 Suppl 1:S107-11.
Image credit: Ted Eytan via flickr. Image has been modified.
Motion graphics by Avocado Video
- animal fat
- animal protein
- beans
- blood sugar
- body fat
- brain health
- brain tumors
- breast cancer
- breast cancer survival
- cancer
- chemotherapy
- chickpeas
- children
- epilepsy
- fat
- fruit
- glucose
- grains
- Harvard
- keto diet
- legumes
- lentils
- lifespan
- longevity
- low-carb diets
- mortality
- protein
- radiation
- saturated fat
- seizures
- split peas
- surgery
- vegetables
- weight loss
- women's health
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Blood sugar, also known as blood glucose, is the universal go-to fuel for the cells throughout our bodies. Our brain burns through a quarter-pound of sugar a day, its “preferred metabolic fuel.” Our body can break down proteins and make glucose from scratch, but most comes from our diet in the form of sugars and starches. If we stop eating carbohydrates, or stop eating altogether, most of our cells switch over to burning fat. But fat has difficulty getting through the blood-brain barrier. But our brain has a constant massive need for fuel, one organ accounting for up to half of our energy needs. Without it, the lights go out…permanently.
To make that much sugar from scratch, our body would need to break down about a half-pound of protein a day. That means we’d cannibalize ourselves to death within two weeks. But people can fast for months. The answer to the puzzle was discovered in 1967. Harvard researchers famously stuck catheters into the brains of obese subjects who had been fasting for over a month, and discovered that ketones had replaced glucose as the preferred fuel for the brain. Your liver can turn fat into ketones, which can then breach the blood-brain barrier and sustain your brain if you’re not getting enough carbohydrates. Switching fuels has such an effect on brain activity that it has been used to treat epilepsy since antiquity.
The prescription of fasting for the treatment of epileptic seizures dates back to Hippocrates. In the Bible, Jesus seems to have concurred. To this day, it’s unclear why switching from blood sugar to ketones as a primary fuel source has such a dampening effect on brain overactivity. How long can you fast, though? To prolong the fasting therapy, in 1921 a distinguished physician scientist at the Mayo Clinic suggested trying what he called a “ketogenic diet,” a high-fat diet designed to be so deficient in carbohydrates it could effectively mimic the fasting state. “[R]emarkable improvement” was noted the first time it was put to the test—efficacy that was later confirmed in randomized, controlled trials. Ketogenic diets started to fall out of favor in 1938 with the discovery of the anti-seizure drug that would become known as Dilantin, but ketogenic diets are still in use today as a third- or fourth-line treatment for drug-refractory epilepsy in children.
Oddly, the success of ketogenic diets against pediatric epilepsy seems to get conflated by “keto diet” proponents into suggesting a ketogenic diet is beneficial for everyone. But you know what else sometimes works for intractable epilepsy? Brain surgery. But I don’t hear people at the gym clamoring to get their skulls sawed open.
Since when do medical therapies translate into healthy lifestyle choices? Scrambling brain activity with electroshock therapy can be helpful in some cases of major depression, so what…pass the electrodes? Ketogenic diets are also being tested to see if they can slow the growth of certain brain tumors. Even if it works, you know what else can help slow cancer growth? Chemotherapy. So why go keto when you can just go chemo?
Promoters of ketogenic diets for cancer, paid for by so-called “ketone technology” companies that will send you salted caramel bone broth powder for a hundred bucks a pound. Or companies that market ketogenic meals report “extraordinary [anecdotal] responses” in some cancer patients, but more concrete evidence is simply lacking. Even the theoretical underpinnings may be questionable. A common refrain is that “cancer feeds on sugar.” But all cells feed on sugar. Advocating ketogenic diets for cancer is like saying Hitler breathed air, so let’s boycott oxygen.
Cancer can feed on ketones, too. Ketones have been found to fuel human breast cancer growth, and drive metastases in an experimental model—more than doubling tumor growth. Some have even speculated that may be why breast cancer often metastasizes to the liver, the main site of ketone production. If you drip ketones on breast cancer cells in a petri dish directly, the genes that get turned on and off make for a much more aggressive cancer, associated with a significantly lower five-year survival in breast cancer patients. Researchers are even considering designing ketone-blocking drugs to prevent further cancer growth by halting ketone production.
And think about what eating a ketogenic diet might entail. High animal fat intake may increase the mortality risk among breast cancer survivors, and potentially play a role in its development in the first place through oxidative stress, hormone disruption, or inflammation.
Men, too: “a strong association [has also been found] between saturated fat intake and prostate cancer progression.” Those in the top third of consumption of these kinds of fat-rich animal foods appeared to triple their risk of dying from prostate cancer. Not necessarily fat in general—no difference in breast cancer death rates based on total fat intake—but saturated fat intake may negatively impact breast cancer survival, a 50 percent increased risk of dying from breast cancer. There’s a reason the official American Cancer Society and American Society of Clinical Oncology Breast Cancer Survivorship Care Guidelines recommend a dietary pattern for breast cancer patients that’s essentially the opposite of a ketogenic diet: “high in vegetables, fruits, whole grains, and legumes, meaning beans, split peas, chickpeas and lentils, and low in saturated fats.”
So far, not a single clinical study has shown “a measurable benefit from a ketogenic diet for any human cancer.” There are currently at least a dozen trials underway, however, and the hope is that at least some cancer types will respond. Still, even then that wouldn’t serve as a basis for recommending ketogenic diets for the general population any more than recommending everyone go out and get radiation, surgery, and chemo for kicks.
Please consider volunteering to help out on the site.
- Sours HE, Frattali VP, Brand CD, et al. Sudden death associated with very low calorie weight reduction regimens. Am J Clin Nutr. 1981;34(4):453-61.
- Cahill GF. Survival in starvation. Am J Clin Nutr. 1998;68(1):1-2.
- Vanitallie TB, Nufert TH. Ketones: metabolism's ugly duckling. Nutr Rev. 2003;61(10):327-41.
- Owen OE, Morgan AP, Kemp HG, Sullivan JM, Herrera MG, Cahill GF. Brain metabolism during fasting. J Clin Invest. 1967;46(10):1589-95.
- Wheless JW. History of the ketogenic diet. Epilepsia. 2008;49 Suppl 8:3-5.
- Rho JM. How does the ketogenic diet induce anti-seizure effects?. Neurosci Lett. 2017;637:4-10.
- Castellini MA, Rea LD. The biochemistry of natural fasting at its limits. Experientia. 1992;48(6):575-82.
- Peterman MG. THE KETOGENIC DIET IN THE TREATMENT OF EPILEPSY, A PRELIMINARY REPORT. Am J Dis Child.1924;28(1):28-33.
- Levy RG, Cooper PN, Giri P. Ketogenic diet and other dietary treatments for epilepsy. Cochrane Database Syst Rev. 2012;(3):CD001903.
- Kossoff EH, Zupec-kania BA, Auvin S, et al. Optimal clinical management of children receiving dietary therapies for epilepsy: Updated recommendations of the International Ketogenic Diet Study Group. Epilepsia Open. 2018;3(2):175-192.
- Gershfeld N, Sultana P, Goldhamer A. A case of nonpharmacologic conservative management of suspected uncomplicated subacute appendicitis in an adult male. J Altern Complement Med. 2011;17(3):275-7.
- Dwivedi R, Ramanujam B, Chandra PS, et al. Surgery for Drug-Resistant Epilepsy in Children. N Engl J Med. 2017;377(17):1639-1647.
- Pope TM. Introduction: Voluntarily Stopping Eating and Drinking. Narrat Inq Bioeth. 2016;6(2):75-77.
- Martin-mcgill KJ, Srikandarajah N, Marson AG, Tudur smith C, Jenkinson MD. The role of ketogenic diets in the therapeutic management of adult and paediatric gliomas: a systematic review. CNS Oncol. 2018;7(2):CNS17.
- Klement RJ, Feinman RD, Gross EC, et al. Need for new review of article on ketogenic dietary regimes for cancer patients. Med Oncol. 2017;34(6):108.
- Gonder U. Article on ketogenic dietary regimes for cancer highly misleading. Med Oncol. 2017;34(6):109.
- Erickson N, Boscheri A, Linke B, Huebner J. Systematic review: isocaloric ketogenic dietary regimes for cancer patients. Med Oncol. 2017;34(5):72.
- Bonuccelli G, Tsirigos A, Whitaker-menezes D, et al. Ketones and lactate "fuel" tumor growth and metastasis: Evidence that epithelial cancer cells use oxidative mitochondrial metabolism. Cell Cycle. 2010;9(17):3506-14.
- Martinez-outschoorn UE, Prisco M, Ertel A, et al. Ketones and lactate increase cancer cell "stemness," driving recurrence, metastasis and poor clinical outcome in breast cancer: achieving personalized medicine via Metabolo-Genomics. Cell Cycle. 2011;10(8):1271-86.
- Martinez-outschoorn UE, Lin Z, Whitaker-menezes D, Howell A, Sotgia F, Lisanti MP. Ketone body utilization drives tumor growth and metastasis. Cell Cycle. 2012;11(21):3964-71.
- Brenner DR, Brockton NT, Kotsopoulos J, et al. Breast cancer survival among young women: a review of the role of modifiable lifestyle factors. Cancer Causes Control. 2016;27(4):459-72.
- Fradet Y, Meyer F, Bairati I, Shadmani R, Moore L. Dietary fat and prostate cancer progression and survival. Eur Urol. 1999;35(5-6):388-91.
- Brennan SF, Woodside JV, Lunny PM, Cardwell CR, Cantwell MM. Dietary fat and breast cancer mortality: A systematic review and meta-analysis. Crit Rev Food Sci Nutr. 2017;57(10):1999-2008.
- Runowicz CD, Leach CR, Henry NL, et al. American Cancer Society/American Society of Clinical Oncology Breast Cancer Survivorship Care Guideline. CA Cancer J Clin. 2016;66(1):43-73.
- Mayer A, Vaupel P, Struss HG, Giese A, Stockinger M, Schmidberger H. Response to commentary by Champ and Klement: Is a ketogenic diet the solution for the hyperglycemia problem in glioblastoma therapy?. Strahlenther Onkol. 2015;191(3):283-4.
- Wilder RM. The effect of ketonemia on the course of epilepsy. Mayo Clin Bull. 1921;2:307–8.
- Dong M, Zhu XM, Zheng W, et al. Electroconvulsive therapy for older adult patients with major depressive disorder: a systematic review of randomized controlled trials. Psychogeriatrics. 2018;18(6):468-475.
- Eenfeldt A. A ketogenic diet for beginners. Diet Doctor.
- Brosnan JT. Comments on metabolic needs for glucose and the role of gluconeogenesis. Eur J Clin Nutr. 1999;53 Suppl 1:S107-11.
Image credit: Ted Eytan via flickr. Image has been modified.
Motion graphics by Avocado Video
- animal fat
- animal protein
- beans
- blood sugar
- body fat
- brain health
- brain tumors
- breast cancer
- breast cancer survival
- cancer
- chemotherapy
- chickpeas
- children
- epilepsy
- fat
- fruit
- glucose
- grains
- Harvard
- keto diet
- legumes
- lentils
- lifespan
- longevity
- low-carb diets
- mortality
- protein
- radiation
- saturated fat
- seizures
- split peas
- surgery
- vegetables
- weight loss
- women's health
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Is Keto an Effective Cancer-Fighting Diet?
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Content URLDoctor's Note
“Keto” has been the most-searched keyword on NutritionFacts.org for months, and I didn’t have much specific to offer…until now.
This is the first in a seven-video series. Here is what’s to come:
- Keto Diet Theory Put to the Test
- Keto Diet Results for Weight Loss
- Is Weight Loss on Ketosis Sustainable?
- Are Keto Diets Safe?
- Keto Diets: Muscle Growth & Bone Density
- Does a Ketogenic Diet Help Diabetes or Make It Worse?
For an overview of my cancer work, watch How Not to Die from Cancer.
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