Might a strictly controlled way of eating be a powerful therapeutic tool for hard-to-treat neurological conditions? That is what Waikato-based Matthew Phillips is working to find out.
Phillips, who describes himself as a metabolic neurologist, is partway through a clinical trial among people with glioblastoma, a very aggressive brain tumour. It is early days yet, but he remains hopeful that the treatment will result in a longer and healthier life for participants.
The regime these cancer patients are on is very intense. It involves regular five-day fasts, where they live mostly on water and salt, supplemented with the odd black tea or coffee. This is timed to coincide with chemotherapy treatment. The rest of the time they eat one or two very low carbohydrate meals a day, with the aim of keeping them in ketosis.
A ketogenic state happens when the body doesn’t have enough carbohydrates to make glucose to burn for energy. Instead, the liver breaks down fat to produce ketones, an alternative fuel source.
There are several ways that being in ketosis might make life difficult for cancer cells and boost the effectiveness of treatments.
“We know that cancer cells require much more glucose than normal cells,” explains Phillips. “So, the idea is that fasting and ketogenic diets are depriving the cancer of its main fuel and surrounding them with a fuel they can’t really use, but that the normal cells love.
“Also, when you fast, or to a lesser extent go on a keto diet, it creates a mild stress that makes the body stronger in the long term – it’s called hormesis. When you stress normal cells, they stop dividing and go into protective mode, so when you hit them with chemotherapy and radiation, they are damaged less. But cancer cells can’t enter stress mode, so they keep dividing, and are possibly even more susceptible because they’re being deprived of their main fuel source at the same time.”
Finally, the keto/fasting regime is aimed at restoring mitochondria function. Mitochondria are powerhouses that make most of the energy for the cells and are particularly dense in neurons. They are very damaged in cancer and the thinking is that by healing them it may help prevent disease returning.
Phillips admits that the first few weeks of following this strict protocol are difficult, as it is such a massive change in lifestyle, and patients need daily support.
“After a few months, they start to know exactly what to do and it’s not that difficult. The psychology is important; they understand that this could potentially be a very powerful treatment.”
He isn’t asking his patients to do anything that he hasn’t tested on himself. He has tried all kinds of experimental approaches, some of them with unpleasant side effects, to find out first-hand what can be done safely and what is best avoided. “For seven years now, I’ve been a strict one-meal-a-day guy with a ketogenic diet.”
He maintains that we are meant to be in ketosis the majority of the time – it is how we evolved – and the modern diet, which keeps us almost constantly running on glucose, is not our natural state. “This might be why we’re seeing a significant rise in lifestyle-related disorders, such as type 2 diabetes, Alzheimer’s and many types of cancer.”
Survival times for glioblastoma can be very short. At Waikato Hospital, says Phillips, the average time at which 50% of patients are dead is 13 months after diagnosis. His first participant is up to 21 months now. He is aiming to sign up more people to the trial and follow them for as long as it takes.
In the meantime, he receives daily messages from people who have advanced cancer and want to learn about metabolic therapy. “I think that’s a reflection of the hopelessness they feel, knowing that the standard treatments will only do so much. I caution against a multi-day fast, unless they have someone medical guiding them who knows what they’re doing. And I stress that we don’t have good evidence yet that a metabolic therapy can enhance lifespan in any advanced cancer. But I don’t think people have anything to lose with a ketogenic or low-carbohydrate diet and a small intermittent fast. And it might help.”
