Monday 8 December 2014

LCHF and Cancer - Let food be thy medicine


Hippocrates, the "Father of Medicine" who lived in Greece around 400 BC came up with this catchy line.  He is also credited with being the first to recognise the difference between benign and malignant tumours. In fact, the name cancer comes from the ancient Greek word for crab (think zodiac signs), as scientists at the time thought that clusters of cancer cells looked like the legs of a crab. So cancer has been around for a long time.

For a rather shorter period of time (perhaps a year or so) my wife has been referring me to the suggestion that low carb diets might have a relationship with cancer treatment.  The theory is that unlike healthy cells that can use either glucose or ketones (fat) for energy, cancer cells cannot consume ketones and so if we starve them of glucose then they will not be able to grow.  So I thought I’d take a close look.

As a background to this subject it is useful to note that some cancers have been increasing in frequency over the last 40 years. In a stable population this ought not to be the case.

It may be that there have improvements in detection over the last 40 years, but even so this recent trend has led some people to speculate whether some modern lifestyle factor might be responsible for the apparent increased rate of cancer cases.  And one of the first places to look is the growth in obesity; the increase in obesity has shown a similar rate of recent change over recent years. There is a good correlation here, but might there be a relationship too? Well, there is a proven relationship with obesity and an increased risk of developing cancer, but what is the nature of this relationship?

A good way to look at this is to start with what we know about what causes obesity - and that we do know. Perhaps what is good for obesity might also be good for cancer more generally?

I’ll assume for now that if you are reading this blog then you probably accept that a LCHF diet is thought by many to be good intervention for managing obesity. What if it were (separately) to be a good intervention for cancer?

Many decades ago, Otto Warburg stated that a hallmark of cancer was the uptake of glucose by cancer cells (1).  Cancer cells rely on glucose for energy; therefore any method of limiting this may help to “starve” cancer cells.  Recent data from several universities, including Johns Hopkins have shown that in brain tumors, the higher a patient’s blood glucose level, the lower their survival.

This research is referred to in an interesting TED talk  on discovering how LCHF diet and high levels of oxygen may combine to starve and damage cancer cells. https://www.youtube.com/watch?v=3fM9o72ykwwThe untested suggestion here is that a combination of LCHF diet and periodic treatment in a pressure chamber might be helpful for some cancer patients.

Further to this, eating a low carb diet not only reduces glucose levels (possible cancer fuel) in the body, it also reduces levels of the growth hormones insulin and IGF-1, meaning cancer cells might not get the signal to divide (see http://www.dietdoctor.com/cbs-using-a-ketogenic-diet-to-starve-cancer). This could explain why several cancer patients have reported how a LCHF diet appears to have halted their cancer growth. One of the best known of these patients is Alix Hayden, who has written about her experiences in her blog http://greymadder.net/

Here is a widely read article introducing these issues. The key suggestion being that cancer is a metabolic disease, not a genetic one, and hence can be affected via dietary changes.
http://www.examiner.com/article/low-carb-ketogenic-diet-beats-chemo-for-most-cancers-says-dr-thomas-seyfried The arguments given seem a bit simplistic to me. Cancer is complicated and I don't see a need to categorize it as purely one thing or the other; more likely it is a bot of both. And I don;t like the suggestion that ketogenic diet beats chemotherapy; there is no data to prove this at all.

Some people have hypothesized that ketones themselves may fight cancer.  This is more speculative with little data, but reports on many separate societies, most notably those in Southern Africa and the Inuit Eskimos of northern Canada reveal few cases of cancer; the diets of both societies include almost no carbohydrates.  Dr FP Fouché (2) reported that in six and a half years as district surgeon in Orange Free State he never saw a case of gastric or duodenal ulcer, appendicitis or cancer amongst a native population of 14,000, even though these diseases were common in the local white or European population on a 'modern' diet. Dr. JA Urquhart (3) served as the district surgeon of the far north of Canada in the 1930s, and in 7 years, with all the x-rays and surgical equipment of his day, has published that he never saw a single case of cancer, and this was in people of all ages.

These are fascinating observations, but without further analysis it is not possible to determine if these are just correlations (with some other unmeasured factors at play) or if there is some direct causation at work here.

When we look at the available science on the subject it is pretty sparse. The data provided so far, principally that of Dr Thomas Segfried, the most vocal advocate of the cancer-as-a-metabolic-disease idea, is very limited and proves nothing either for or against the idea.
It would be great to have some wider trials and research further into this subject, and fortunately there are some good studies happening now. So we should know a little more about this subject soon.

If you want further reading then there is a thorough review of this subject here: http://www.sciencebasedmedicine.org/ketogenic-diets-for-cancer-hype-versus-science/#more-32073. Be prepared for some un-minced words though. The author clearly likes the subject and thinks there might possibly be something in it, but tends to be pretty dismissive of anything not backed up by solid scientific research; but that is to be expected from sciencebasedmedicine.org.

But for now I think I'll chalk this one up as a 'maybe'.


References
1.          Warburg O: On the origin of cancer cells. Science 123:309-14, 1956,http://www.ncbi.nlm.nih.gov/pubmed/13298683
2.          Fouché FP: Freedom of Negro Races from Cancer. Br Med J 1, 1923
3.          Urquhart JA: The most northerly practice in Canada. 1935. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1336486/?page=1




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