What Is the Ketogenic Diet?
The ketogenic diet is high fat, moderate protein and very restricted carbohydrates. The reduced supply of glucose causes our internal biochemical pathways to switch to metabolizing fat instead of glucose for ATP energy. By lowering the intake of carbohydrates to a very low amount, the body is induced into a state called ketosis. Nutritional ketosis is a natural reaction from the body to help humans and animals survive when carbohydrate or starvation occurs. Ketones are produced by the liver as a by-product of fat breakdown when glucose levels are low.
The body is put into this metabolic state not through starvation but through the starvation of carbohydrates. If you give the body high quality fats and take away carbohydrates the body will begin to burn ketones as a main source of energy. Humans have been able to do this for countless millennia.
There is a common misinterpretation of nutritional induced ketosis and ketoacidosis.
Nutritional ketosis is a controlled, insulin-regulated process which results in a mild release of fatty acids and ketone body production due to the ‘fasting’ of sugar/reduction of carbohydrate intake.
Ketoacidosis, on the other hand, is caused by the lack of insulin in the body. Without insulin or a functioning pancreas, the blood sugar levels rise to high levels. This excess amount in turn produces abnormal quantities of ketones. A classic example of this occurs when an insulin-dependent diabetic does not get enough insulin over time. This IS NOT nutritional ketosis.
What exactly does it mean to restrict carbohydrates?
On a typical SAD (standard American/Australian diet) the ratio is about 50% carbohydrate, 15% protein and 35% fat. The main source of energy is carbohydrates.
On a ketogenic diet the ratio consists of 80% fat, 15% protein and 5% carbohydrates. Therefore, the main source of energy is fats (lipids).
A 5% carbohydrate intake generally means less than about 30grams of carbohydrate consumption per day. To reach ketosis, no more than a maximum of 40-50grams of carbohydrates per day should be consumed.
Let me visualize how much sugar intake this is; 30-50 grams of sugar is roughly three regular carrots or one medium sized apple.
What Can I Eat On a Ketogenic Diet?
Foods that can be eaten in ABUNDANCE:
- Grass-fed and wild animal sources –
grass-fed beef, lamb, goat, venison, wild caught fish and seafood, pastured poultry, free range eggs, gelatin, ghee, butter, offal (liver, heart, kidneys, and other organ meats)
- Healthy fats –
saturated (chicken fat, duck fat, goose fat, clarified butter, ghee, butter, coconut oil)
monounsaturated (avocado, macadamia and olive oil)
polyunsaturated omega 3s (flax oil, fish oil, hemp oil)
- Non starchy vegetables
- leafy greens (Swiss chard, bok choy, spinach, lettuce, chard, chives, radicchio etc.)
some cruciferous vegetables like kale and kohlrabi
celery stalks, cucumber, zucchini, asparagus
- Beverages and condiments
water, coffee (black or with some coconut milk/cream), tea
mayonnaise, mustard, pesto, bone broth, pickles (as long as made without sugar), fermented foods (kombucha, kimchi, and sauerkraut)
all spices and herbs, lemon, lime and zest
egg white protein and gelatin
Foods that should be eaten MODERATELY:
- Vegetables, Mushrooms and Fruits
some cruciferous vegetables (cabbage, cauliflower, broccoli, Brussels sprouts, fennel, turnips)
nightshades (eggplant, tomatoes, capsicum)
some root vegetables (spring onion, leek, onion, garlic, mushrooms, squash)
sea vegetables (nori, bean sprouts, sugar snap peas, artichokes)
berries (blackberries, blueberries, strawberries and raspberries)
coconut, rhubarb and olives
- Grain fed animal sources and full fat dairy
beef, poultry, eggs and ghee
- Nuts and seeds (best raw if available)
pecans, almonds, walnuts, hazelnuts, pine nuts, flaxseed, pumpkin seeds, sesame seeds, sunflower and hemp seeds
- Fermented soy products
only if GMO free like tempeh, miso, soy sauce or coconut aminos
edamame is unprocessed
arrowroot, xanthan gum
cocoa and carob powder, extra dark chocolate 70%
dry red wine, dry white wine, spirits (unsweetened)
- Note: some vegetables like celery root, carrot, beetroot, parsnip and sweet potato can be eaten occasionally but depends on your average carbohydrate limit for the day.
Foods which should be AVOIDED:
- sugary drinks
- alcoholic drinks
- processed foods
- soda and juice
- vegetable oils
- sweet fruits
- dried fruits
- low fat foods
- processed treats
- factory farmed meats and fish
- grains and gluten
What Happens When You Cheat?
Glucose is the easiest molecule for your body to convert and use as ATP energy, so it will be chosen over any other energy source. Therefore, if carbohydrates are eaten more than the daily limit of a ketogenic diet, the body will in seconds switch back to glucose metabolism. People who cheat are constantly putting themselves back to square one and out of ketosis. Additionally, they will gain a lot more weight because of the combined effect of carbs and fat. This is not a diet you can cheat with, ketone levels in the blood will lower and the person will need to start again.
A day on a ketogenic diet could look like this:
Check out the info-graph taken from Practical Keto Meal Plans for Cancer by Patricia Daly.
How Long Does It Take to Enter Ketosis?
It can take anywhere from 4 days to 4 weeks to enter ketosis. It depends on the individual and whether the restricted carbohydrate limit is maintained vigilantly. Exercising can help speed up the process since it helps deplete the glycogen stores within the body.
Why Can’t I Get into Ketosis?
Too much protein consumption can result in elevated blood glucose levels through a process called gluconeogenesis. This could be reason why some individuals are unable to build ketones. Although eating a restricted low carb, the protein ratio could possibly be too high. Gluconeogenesis (GNG) is a metabolic pathway that results in the generation of glucose from certain non-carbohydrate carbon substrates.
Are You Eating Enough Fat?
This is a very important question on the ketogenic diet. Whether or not a person is eating enough lipids (fats) can be measured through the ketone levels. The ketone level should be between 1-3. If the ketone levels go beyond 4-5 it is important to see a doctor.
1. Urine testing
Urine test strips are not as accurate and may not work for some individuals. The strips only show excess ketone bodies excreted as acetoacetate via urine but there is nothing which tells the person about the level of ketones in the bloodstream which could be higher.
2. Blood testing
This is the most accurate way to measure the ketone bodies, beta-hydroxybutyrate. Blood ketone meters can precisely determine ketone levels in your blood but they’re also pricey. Very good units are self finger-stick variety. Check resources for this online.
How Can a Ketogenic Diet Work for Cancer Patients?
When we eat a carbohydrate filled meal our digestive system breaks down the carbs into glucose which enters into our blood stream. When this happens our blood sugar levels peak and this triggers the pancreas to excrete insulin and bring the blood sugar level back down. So why is it imperative to lower glucose and insulin in the blood stream? This is because insulin pushes the glucose into the cells but cancer cells have an advantage and take the extra glucose. Resulting in cancer growth.
The ketogenic diet lowers the levels of insulin inhibiting hormones such as the insulin growth factor IGF-1 and other metabolic pathways which promote cancer progression. Cancer cells have defective mitochondria (energy house), therefore glucose supplies leave them with no possibility to repair the oxidative stress which constantly bombards cells. Cancer cells are then more likely to suffer injuries from interactions with oxidizing free radicals. Radiation therapy works by increasing free radical activity around cancer tissue and studies have shown that being in nutritional ketosis seems to enhance this destructive free radical effect.
There have been published research papers on ketogenic diets and the anti-inflammatory effect of ketone bodies on certain conditions like epilepsy, Parkinson’s Disease, Alzheimer’s Disease, Type 2 diabetes, cardiovascular disease, autism, migraines, stroke, depression and of course cancer.
Unlike the normal cells within our bodies, data has shown that cancer cells are unable to generate a substantial amount of energy from ketone bodies and rely immensely on glucose. This desire for glucose is correlated to the fact that cancer cells have defective mitochondria; therefore, in rapidly growing tumors the glycolytic rate is up to two hundred times higher than normal tissues.
Since cancer cells do not have the capability to metabolize ketones as a source of ATP, the ketogenic diet destabilizes tumor tissue DNA. Therefor, reduce tumor size over some time and this in turn can enhance life for cancer patients.
It has even been studied and stated that a ketogenic diet could work well along side mainstream cancer treatments such as chemotherapy and radiation.
What are the benefits?
- reduce the development of new blood cells required to fuel tumors
- restore apoptosis of cancer cells
- destabilize the DNA in tumor cells
- over time reduce the tumor size
- reduce levels of insulin and cancer promoting hormones
- reducing inflammations
A study published in June 2013 The Ketogenic Diet and Hyperbaric Oxygen Therapy Prolong Survival in Mice with Systemic Metastatic Cancer, explained that the low carbohydrate, high fat diet decreased blood glucose and elevated blood ketones had a slowed progression of cancer in both animals and humans. The study showed that the ketogenic diet increased survival time by 56.7% in mice with systemic metastatic cancer. The hyperbaric oxygen did little on it’s own to influence the cancer progression but with the combination of ketogenic diet had a significant effect increasing the survival time to 77.9% in mice.
Another study published in July 2011 discussed how tumors utilize glucose as their main source of energy. Thus this diet for a cancer patient would starve the carbohydrate ‘glucose’ source which tumors thrive from. This study was conducted with 16 patients with advanced metastatic tumors and without conventional options. The study suggested the ketogenic diet is suitable for even completely advanced cancer patients. There’s no severe side effects and might improve some aspects of their quality in life. It documented an improved emotional functioning and less insomnia.
Sounds Like an Effective Diet? What are the drawbacks?
Unfortunately, nothing is ever as black and white as it seems.
This diet is considered a last resort treatment for many cancer patients, due to the one-way street this diet entails. Once the metabolic process changes over to ketones reverting back to glycolysis as the major source for ATP can result in a dramatic and detrimental growth of cancerous tissue. It’s dangerous due to the depriving and starving of the cancer cells and then the re introduction of glucose (even if it’s a low carbohydrate diet), the cancer regains its food source and can explode much more aggressively.
That this is a one-way street for cancer patients is NOT expressed enough online or made clear to patients.
Secondly a point which many people forget after reading all the benefits of a ketogenic diet are the restrictions. Ketogenesis is an extremely restrictive, commitment requiring diet. It can’t be done half-heartedly and as a cancer patient it should be a lifestyle choice not a trend you follow now to see if it works. Many people have troubles adhering to the diet, especially at social functions, outings, restaurants, work environments, gatherings and so forth.
Before considering this diet, it needs to be checked and established that there is an adequate production of bile acids and pancreatic lipase. If a patient has a cholecystectomy (gall bladder removal) the ketogenic diet should not be pursued. Even in healthy individuals, supplementation of lipase and bile salts might be required due to the increase in fat metabolism.
Additionally, this diet is lacking in many different nutrients. The ketogenic diet lacks in grains, fruits, some vegetables, and legumes. Therefore, lacking in vitamin B’s, phytonutrients and antioxidants. This diet would require additional supplementation and checking of the blood work and mineral levels to make sure the body stays within homeostasis. Also due to the increased intake of fat it can lead to an acidified system. Therefore, the regular intake of chlorophyll and other foods rich in phenols aid to alkalize the body.
Lastly the transition over to a ketogenic diet isn’t always considered easy. There are several different symptoms and experiences an individual can have. It has been documented that individuals can lose minerals such as salt, potassium and magnesium. Also weight loss is experienced through the ketogenic diet. Many people can lose several kilograms until reaching a weight that stays stable, it is certainly something to keep an eye if weight keeps dropping.
- Check out the following two books for more detailed information, along with numerous scientific references and background data:
1) Cancer as A Metabolic Disease, by Thomas Seyfreid, PhD. (VERY science-heavy)
2) Tripping Over the Truth, by Travis Christofferson. (best for the layperson)
Additional information can be found through Dr. Dan Pompa’s website, where much of this article data was sourced (see below)
- Feeling of fatigue
- Light headed
- Blood sugar drops
- Strong sugar cravings
- Feeling of weakness
- Muscle cramps or aches
- Disrupted sleep
- Frequent urination