The keto diet and cancer
When discussing the keto diet and cancer, let us say that the keto diet is not a cure for cancer. Furthermore, the keto diet should only be followed in combination with (not as a replacement for) your ongoing medical treatment.
You must always consult with your doctor if you are a cancer patient and are considering trying the keto diet.
That being said, we believe there are many health benefits which suggest the keto diet is beneficial for cancer patients and something worth discussing with your professional health advisor.
What is cancer?
Cancer is a disease where abnormal cells divide in an uncontrolled way and spread into surrounding tissue.
Cancer can start almost anywhere in the human body, which is made up of trillions of cells. Normally, human cells grow and divide to form new cells as the body needs them. When cells grow old or become damaged, they die, and new cells take their place.
When cancer develops, however, this orderly process breaks down. As cells become more and more abnormal, old or damaged cells survive when they should die, and new cells form when they are not needed.
What triggers cancer?
Radiation, chemicals, stress, genetics and a wide range of other things that can initiate cancer. These potential triggers damage your cells’ mitochondria (“the powerhouse of the cell”). Mitochondria basically produces all the energy in your body.
Understanding how cells grow can help us see how a ketogenic diet might help to combat cancer.
Cell metabolism in cancer cells and non-cancer cells
In normal cells, the human body takes glucose and combines it with oxygen to create energy. Cancer cells are different. Cancer cells actually need a lot of glucose to grow and to stay alive because they’re inefficient at creating their own energy due to their impaired mitochondria.
So, if we deprive ourselves of carbs (glucose) and added sugars – like we do on the keto diet – we keep our insulin levels down, and we can deprive cancer cells of a lot of what they need to grow and survive.
Insulin plays a large part in allowing cells to grow. In a normal cell, it allows glucose to enter cells to promote growth – and it also does this with cancer cells. In fact, certain cancer cells have ten times the receptors for insulin compared to normal cells. What does that tell you? Cancer cells love sugar. (In fact, when you do a PET scan to screen for cancer, it works by combining a low-radiation substance (radiotracer) with glucose so your scan essentially detects the sugar consumption by the cancer cells.)
So, if we can lower the insulin level – the pathway that give cells energy – we can potentially decrease cancer growth.
The keto diet is a great anti-cancer diet
So, by eliminating sugar from your diet, won’t you also be starving your own healthy cells? No. The good news is that healthy cells are quite happy and able to use ketones for fuel. So, the solution is to switch the entire fuel source of what you put in your body from sugar to ketones, i.e. to trigger and stay in ketosis – your body’s fat-burning state where it uses fats for energy and has no need for sugar.
Sugar is a very harmful fuel that creates a lot of other problems with other organs. You want to run your body on ketones – the by-product of fat-burning. By starving cancer cells of sugar, you can help slow down the growth rate and there’s anecdotal evidence that this has helped reverse some people’s diagnosis. At the very least, eliminating sugar is a powerful cancer prevention measure.
Most cancerous cells cannot live on ketones. This is why the ketogenic diet is so essential to help starve cancer cells. Healthy cells can live on ketones, many cancerous cells cannot. Without a continual supply of energy, cancer cells may be more susceptible to oxidative stress and DNA damage, making them more sensitive to chemotherapy treatment.
A study on how keto affects sugar-dependent cancer
A 2019 study was published in the journal, Cell Reports and took a look at squamous cells lung cancers, a type of cancer cell that really thrives on sugar. The study found that a ketogenic diet did stop the growth of a squamous cell. (Now, it should be noted that this may be a slightly biased study as they chose a type of cancer they knew relied heavily on sugar. However, it is still an interesting finding to show how keto can effectively inhibit certain types of cancer cell.)
The study (on mice) also showed that a non-keto diet did not impede the squamous cell growth and the cancer continued to grow. However, the same study also looked at human subjects – not mice – who had lung and oesophageal squamous cancers and found that there was a high correlation between those with these types of cancers and levels of glucose in their body. Correlation is not causation but it’s interesting to note. Sugar creates a more cancer-friendly environment in your body.
Sadly, cancer can run on another type of fuel
If cancer could only run on glucose, that would be great. However, unfortunately, cancer can also survive on an amino acid called glutamine. Whilst we can cut out sugar, the problem is, glutamine is everywhere in your diet and impossible to completely eliminate. Glutamine is found in meat, eggs, fish, vegetables, nuts, seeds… everything.
What can be done about this?
There’s some promising research being done right now using the ketogenic diet with a chemical called DON (6-diazo-5-oxo-L-norleucine) which can inhibit glutamine. It’s what’s known as a glutamine antagnoist. The results are promising but there are side effects and more research is needed.
However, many researchers are excited about the potential of combining the keto diet and inhibiting cancer cells’ ability to use glutamine as a way of treating cancer patients. Other research is investigating ways to put glutamine out of the reach of cancerous cells but still supply it to healthy cells.
In the meantime, there are things you can do right now to at least reduce glutamine. Green tea and peppers (all types) have been shown to contain chemicals that inhibit glutamine. Finally, intermittent fasting is another tool you can use to fight cancer.
Keto works better against some cancers than others
Unfortunately, keto may not be effective against every cancer as some types of cancer can survive low-glucose environments. So, how well the keto diet works in combatting cancer also depends on the type of cancer. Some cancers are heavily-dependent on glucose and cannot use ketones for fuel and so a keto diet can really help restrict these cancers. Other types however are less reliant on sugar as fuel and so keto has less of an effect.
However, the good news is, a common theme seems to be to that no matter what type of cancer we’re talking about, keeping your insulin and glucose levels low helps. Remember, insulin triggers cell-growth – whether that’s healthy cells or cancerous cells.
Keto is not a cure for cancer but it’s an important tool
So, whilst the ketogenic diet does not cure cancer, it can impede or even stop certain types of cancer cells from growing. It’s part of the solution, not part of the problem – and in the fight against cancer, that’s huge. See the keto diet as additional tool in your arsenal. By running your body on ketones which healthy cells can happily use (but which most cancer cells cannot use because of their impaired mitochondria), you essentially starve certain types of cancer cells when you switch to the keto diet.
In summary, while we still do not have a cure for cancer, there are things we can do to give slow its growth and give ourselves the best chance of overcoming it:
- Eliminate sugar from your diet, i.e. start the keto diet
- Drink large amounts of green tea
- Eat peppers (in amounts that do not kick you out of ketosis)
- Practise intermittent fasting, 16:8 (16 hours fasting window, 8 hours eating window). Intermittent fasting also reduces blood sugar levels, further depriving cancer cells of fuel. Intermittent fasting is a fascinating topic in its own right and we look at it in greater depth here.
Keto is not a cure but it’s a definite step in the right direction.