Note to reader: This article was originally written in 2015 by Christina Santini.
Please note: I do not recommend a keto-diet for cancer in general, but specifically in regards to enhancing the effect of chemotherapy only.
Cancer cells grow in all of us at any given time. The difference between someone who gets sick from cancer and someone who doesn’t is their immune system’s ability to constantly kill new and growing cancer cells. That means the key to treating cancer lies both in symptomatically focusing on targeting and eliminating cancer cells that have managed to multiply out of control, but even more importantly in optimizing the immune system to effectively be able to suppress cancer cells on its own.
A weak immune system causes a domino effect of disasters in the body, one of which can be cancer.
Many factors influence our immune system and can block it from functioning optimally. When we have a blockage in the system i.e. heavy metal toxicity, virus or bacteria load, hormone imbalance, nutrient deficiencies, we have the perfect storm for cancer to use this opportunity to grow (1,2,3).
Cancer is not just one disease, but many – and it is a symptom of an underlying cause that needs to be identified to prevent relapse.
Let’s get this straight: you cannot “cut” (surgery) or “drug” (chemo/radiation) your way out of cancer. These methods offer nothing but symptom management. The root cause of disease remains untouched until that is treated – only then have we effectively cured any disease for that matter.
The current standard method of treating cancer is via chemotherapy and/or radiation. It is important to note, that none of these methods target the underlying cause, nor do they enhance the immune system’s own ability to fight disease and suppress new cancer cells from growing in the long run. This is also why the success rate of both treatments is incredibly poor.
Chemo used alone only contributes on average about 2% to the overall 5-year survival rate (4).
And even this 2% success rate is slightly misleading. It has become clear that some cancers are easier affected by chemo than others, while others remain unresponsive and thus chemo tends to do more harm than good in those cases.
The cancers that respond in favor of chemo are testicle cancer where it is 41.8% effective, and Hodgkin’s Disease where it is 35.8% effective along with Children’s leukemia which has a success rate of 50-80%. (4,5)
So how does chemotherapy work?
Chemo is cytotoxic – it is what was used in world war 2 to kill people in the concentration camps, so this treatment comes with a high price tag when talking side effects.
The drawbacks of chemo are many. And a combinatory approach should always be used both to increase efficacy and to prevent onset of later diseases.
Autoimmune issues are typically seen following chemotherapy.
This is because chemotherapy damages DNA and can cause permanent damage throughout the body, in addition to that chemo itself is highly carcinogenic.
Chemotherapy utilizes systemically administered drugs which kills cells by promoting apoptosis (regulated cell death) and frank necrosis (disordered cell death). Chemotherapy woks via the following main pathways:
DNA damage
Inhibiting DNA repair
Working against cell metabolism
Working against tubulin (a key protein that maintains a cell's structure)
DNA will be dividing fastest in cancer cells. The problem is that chemotherapy is a systemic treatment and so actually damages all cells in the body. (5)
This is where the ketogenic diet gets interesting.
Our cell replication process slow down (and thus the potential for anti-aging), when we are in a state of ketosis. This can either be reached through fasting or via a ketogenic diet. Add to that, we know that chemotherapy will first go after the faster dividing cells in the body.
This means, that by pushing our body into a state of ketosis while undergoing chemo, we can protect more healthy cells by slowing them down, and increasing targeted killing of cancer cells.
Researchers have shown that adding a ketogenic diet during chemo greatly increases the efficacy (6,7).
Normal cells produce energy by breaking down glucose, fatty acids and amino acids via oxidative metabolism. On contrary, cancer cells create increased levels of reactive oxygen species (ROS) and oxidative stress due to mitochondrial electron transport chain defects and this makes them seem to depend more heavily on glucose as fuel to remove the increased levels of ROS.
A ketogenic diet is 90% fat-based, 8% protein and 2% carbohydrate.
A fat based diet like that reduces glucose metabolism which leads to a decrease in the antioxidant NADPH needed for the cancer cells’ ROS metabolism. Since their primary pathway of energy metabolism is downregulated, this leads to increased oxidative stress in the cancer cells, which seems to make them more sensitive to chemotherapy and radiation.
Apart from the cancer cells becoming more sensitive on a fat-based diet to chemotherapy, there are a few other ways a ketogenic diet works synergistic with chemotherapy:
Fasting and ketosis slow down replication of healthy cells, leading to fewer becoming the target for chemo
Cancer cells will continue to divide at same rapid pace and thus be the main target for chemo
Cancer cells are weakened by lack of readily supply of glucose, normal cells are not
What does this mean in terms of what should be on your plate?
If you are planning on, or currently undergoing chemotherapy, a ketogenic diet should be on your plate – both to protect as many healthy cells as is possible during chemo and to increase efficacy of chemotherapy treatment.
A ketogenic diet is not about calorie restriction but it is about carbohydrate starvation.
Meals will be veggie and fat-based with a bit of protein, preferably vegetarian based or some fish and chicken. Red meat for cancer is a no-go. We are talking about cutting out all starchy carbs like rice, grains and potatoes. This is not an Atkins type of diet though, which would be a disaster for cancer. High animal protein intake has shown to be tumor growth enhancing (8,9). However it is important to keep things in perspective here: a healthy immune system requires protein to function and kill cancer cells, so cutting out all protein is not the way forward either.
To sum it up, this translates into following “eat this, not that” ketogenic guidelines adjusted to fit that of cancer patients:
Eat less:
Tubers and root vegetables (potatoes, yams, beets)
Grains
Sugar
Fruit (except berries and grape fruit, low carb content)
Eat more:
High-fat dairy: butter, heavy cream, yogurt
Green leafy vegetables
Above ground vegetables
Nuts and seeds
Berries, grapefruit and avocado
Meats: Chicken, turkey, fish
Fats: Virgin coconut oil, flax oil, walnut oil, macadamia oil, olive oil etc.
Interesting to note here is that you can stimulate the production of ketone bodies by consuming coconut oil (10). Coconut oil contains medium chained fatty acids (MCT) as one of few food sources. MCTs go to your liver where they are converted into ketones, bypassing the bile completely.
Is the ketogenic diet the perfect anti-cancer diet?
Many of the foods in the above “eat less” category has anti-cancer compounds in them, so it is not possible to say that a ketogenic diet is the most efficient anti-cancer diet when looked at it isolated. What we can say is, that it is the diet that works best to increase the efficacy of chemotherapy. Depending on types of treatments undergone, the nutrition strategy must adapt to match that – everything must work in synergy for best results.
Some cancers will not respond to chemo, ketogenic diet or not.
Defects in the FBW7 gene has been linked to a variety of cancers, including breast and colon. A defect in this gene has been found linked to chemo drug resistance (11,12). In these cases, it will matter little what dietary approach one combines chemo with, because the effects of chemo will only fall on the negative side. Keeping in mind that chemo is cytotoxic, it will in these cases lead to an increased and earlier death, before the patient would die from cancer. Chemotherapy is a tricky treatment, because if not used targeted and combined with other methods, many cancer patients die from the treatment rather than cancer itself (13).
Screening for gene FBW7 will prove to be immensely important in the future, when deciding whether a patient should undergo chemo at all to avoid treating in cases of chemo drug resistance.
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