There is an energetic debate happening within the cancer community as to whether or not cancer is a genetic or a metabolic disease. I believe that understanding the origins of the uncertainty provides a way for cancer patients to gain a better insight into how their bodies are malfunctioning. Cancer is a disease so complex that doctors don’t even try to explain it, but that can leave patients confused, frightened and disempowered, and that’s never a good thing.
The reason cancer has such a legendary reputation is because it disables normal cell destruction mechanisms meaning the cells are effectively immortal, free to replicate indefinitely. Cancer cells have also learned to commandeer more than their fair share of fuel so they have no trouble outstripping the growth of other cells.
A complex disease
No single person, least of all me, understands all the mechanisms involved in the origins and progress of cancer; indeed it is commonly thought that cancer is in fact not a single disease at all. Attempts to cure people of cancer have historically been through surgical removal of tumours and a range of ‘cytotoxic’ treatments that aim to kill the cancer before the patient. These treatments have been refined and honed over decades, and success rates when cancer is caught early are increasing all the time.
Our understanding of the mechanisms of cancer has also improved significantly in the last twenty years leading to breakthroughs in new medications that target cells more precisely. Clearly, researchers are looking to exploit any weakness that cancer cells may have compared with healthy cells as this would increase the chances of killing them and leaving healthy cells intact.
A way in to cancer?
One weakness that nearly all cancer cells share is faulty metabolism. It’s one of the ‘hallmarks of cancer’ and recently scientists have begun to wonder again if this might provide a key to a cure. In 1927, Otto Warburg identified the process that leads to healthy cells becoming cancerous. He showed that depriving healthy cells of oxygen would completely change the way they make their energy and lead to cancerous cell behaviour.
To get technical for a second, when there is not enough oxygen in circulation (for example during intensive exercise) cells can switch from glucose oxidation, the normal way of making energy, to glucose fermentation (anaerobic glycolysis); and when oxygen levels are restored, normal respiration resumes. If oxygen deprivation is prolonged Warburg observed that cells move irreversibly to fermentation even when oxygen is restored (aerobic glycolysis) and the resultant cells behaved as cancer cells. He also noted that fermentation requires more glucose – about 20 times more – to create the same amount of energy and that, while normal processing of glucose produces neutral end products that are easily excreted (carbon dioxide and water), the by-products of fermentation are bio-active and potentially toxic (more on this later).
Warburg won a Nobel Prize for his work on the metabolic origins of cancer but it was eclipsed by the discovery of DNA in the 1950s and the identification of damaged DNA in (most but not all) cancer cells, an observation which was thought to be causative. As a result, the genetic theory of cancer was born and, for the last 60 years, it has received most of the attention and, perhaps more importantly, funding.
Genetic or metabolic?
The more we understand about cancer genes, the more unlikely it appears that they will provide a quick route for curing cancer. While some genes – P53 in particular – seem to play a role in most cancers, generally speaking the gene damage is chaotic and random. Pioneering attempts to classify and organise the genetic defects in different kinds of cancers via The Cancer Genome Atlas Project seems to have resulted in more confusion, rather than a list of genetic targets. Moreover, while there has been some success in targeting individual genes, results have suggested that new mutations are happening so quickly that targeted drug approaches would likely be redundant almost before they could be applied. It’s a difficult problem that is taxing the brightest and best people on the planet.
Intriguingly, proponents of the metabolic theory of cancer, tend to see the genetic damage as a symptom rather than a cause of cancer. Glycolysis is only supposed to be the ’emergency generator’ in your cells: useful to make sure you don’t run out of energy while fleeing the proverbial sabre-toothed tiger, but too expensive and toxic to supply normal fuel needs. When it’s becomes the primary energy pathway the by-products are capable of inflicting damage on cellular DNA (genes) tipping the balance of the cell towards inflammation, proliferation and metastasis. The inference is that genetic mutations may be a downstream effect of faulty glucose metabolism and mitochondrial dysfunction, rather than the cause.
So, although there is no question that cancer is a disease with a genetic component, some researchers are starting to look for other avenues of research. There are exciting developments in immunotherapy, exploiting the immune system’s ability to flag the presence of cancer cells, and allowing precise targeting. And there is renewed focus on the ‘Warburg effect’.
Could it be sugar?
Only a small percentage of cancers are caused by inheritance of faulty genes, and some by DNA damage and viral assault, but we are told that the majority are lifestyle related. Indeed, Dr Paul Clayton published a study of lifestyle and nutrition in the Victorian era showing that, even though cancer diagnosis tended to occur at later stages, survival tended to be better, concluding that there is something about our modern lifestyle that uniquely accelerates the disease.
We know that patients with type 2 diabetes, a disease of uncontrolled blood sugar, have a higher incidence of cancer – and that patients taking metformin, a drug used to reduce blood sugar levels, have a lower incidence of cancer. Biomarkers of glycosylation (a damaging change to protein structures which occurs when blood sugar is uncontrolled) are considered useful for cancer diagnosis and prognosis, and increased sugar uptake is the mechanism behind PET scans.
Warburg was convinced that his work showed that the power to overcome cancer was in the hands of the individual. His theories give us an insight into how we may be able to prevent cancer from starting and progressing. Although oxygen is involved in the early stages, and an important part of prevention, by the time we have a diagnosis it’s probably too late to target oxygen delivery – we need to look at the metabolic factors driving growth.
Metabolic cancer researchers are focussing on cutting off the fuel supply to cancer cells by reducing the availability of glucose in the blood, but treatments using this approach are a long way off. Meanwhile, many nutritional therapists agree that a glucose restricting diet may be useful alongside conventional medical treatment in helping patients reduce the occurrence and recurrence of cancer.
An exciting theory
In practical terms, you can take advantage of Warburg’s theory by following a ketogenic diet which restricts sources of glucose in the diet and increases sources of fats (which are converted to ketones to make energy). The idea is that, since cancer cells need 20 times more glucose than healthy cells, and since healthy cells are perfectly capable of existing on fat as fuel (in the form of ketones), then by restricting sources of glucose in the diet we may be able not only to restrict the ability of cancer cells to produce the energy they need to survive and replicate, but also put them under metabolic stress, increasing their likelihood of dying, simply by starving them.
The safety of the ‘ketogenic’ diet is well established and has been used to treat epilepsy in children since the 1920s. Although animal studies abound, and there are some compelling ‘anecdotal’ cases in humans, it’s important to make clear that the ketogenic diet is not a proven cancer therapy, nor is it being used by nutritional therapists as a ‘cure’ for cancer. It is an experimental approach which has generated a lot of interest, commanded the attention of a lot of members of the scientific community, and may yet prove to be effective in cancer. For me the ketogenic diet has become an important therapeutic clinical tool because it can:
– allow rapid and sustained weight loss
– improve blood cholesterol profiles
– reverse insulin resistance
– normalise fasting glucose
– improve hormone balance (interesting for hormone-dependent cancers)
– reduce inflammatory pressure
– improve energy levels and cognitive function
– reduce oxidative stress in the body
– reverse diabetes and obesity
– control epilepsy
A diet with so many positives has the potential to benefit most 21st century humans – if only because of the potential to feel so much better. But we also know that obesity, diabetes, insulin resistance, raised fasting glucose, inflammation and oxidative stress are linked to cancer occurrence – so it makes sense that a strategy to improve all these might have the potential to improve cancer too.
A delicious way to help yourself
The ketogenic diet is not difficult or overly restrictive; in fact you may find you can eat lots of delicious foods that you formerly believed were ‘bad for you’. There are many books published about it now including my own Dissident Diet which is geared towards weight loss but can equally be used to battle cancer. Breakfast tends to be the most difficult choice as the conventional cereal and toast routine is ruled out – but eggs and bacon are back on the menu. Main meals and eating out are a doddle as long as you stay away from the bread basket and sweet trolley. You can get started for yourself by following a low carb high fat (LCHF) diet: I recommend The Real Meal Revolution and The Ketogenic Cookbook as excellent resources along with my own recipe website if you feel you want to go it alone.
But if you are already dealing with a cancer diagnosis then your body is already trying to juggle some major system imbalances, and it’s likely that you need to make some lifestyle changes along with your diet to return to a better state of health. I recommend finding someone to help you. Working together allows us to create a more tailored diet for you which, as well as restricting glucose, takes into account your health history and lifestyle. We can also look more closely at your individual susceptibility with functional and genetic testing. You can read more about how that works on my consult page and by looking at the case studies I have written about.
I do hope that everything I’ve written here has given you a clearer understanding of your disease, and maybe given you some hope that making changes to your diet may have the potential to improve your overall health. Please get in touch if you would like some help with that.
NB You may find it confusing that, having questioned the genetic theory of cancer I suggest that genetic test data may help us improve your health. When we look at your genes together we wouldn’t be looking at the genetic mutations in your tumour but at the genes you were born with. These can predispose to nutrient deficiencies, inflammation, poor hormone clearance etc. and respond to nutritional intervention, improving the cellular environment and providing a less hospitable environment for cancer cells.