Nutritional support in cancer

I am not a cancer specialist, and I cannot replace your oncologist and/or surgeon. Nor do I have the training or qualifications to tell them what to do. What I can offer you if you have a diagnosis of cancer is best described as adjunctive nutritional and metabolic support.

Cut out carbs

The most important single thing to do when you have a diagnosis of cancer is to cut out carbohydrates as much as possible, and replace them with organic protein and fats/oils. For several reasons;

  1. Cancer cells depend on sugar, and use 10 times as much of it as do normal cells. It is a “growth factor” for them.
  2. Vitamin C is shaped like a sugar, and goes into cells via the glucose transporter channels, of which cancer cells have a lot more than normal cells. This will only happen if there is very little sugar available for them to feed on.
  3. Most of us are running short on oils, which the immune system needs to make white blood cells that may be able to fight the cancer. They also need vitamin C of course.
  4. Metabolising carbs switches off the normal burning of fats for energy, which also inhibits the normal removal of toxic damage from cells.

The Atkins diet was a rather poor version of this; look up “ketogenic diet” or “palaeolithic diet” for a better one. There are e-books (see Ketogenic Diet Resource for instance), apps (KetoDiet Basic for instance)

Vitamin C

The use of vitamin C (ascorbic acid) in cancer is the legacy of Linus Pauling, twice Nobel Prize winner, who with Abram Hoffer invented the term “orthomolecular” for therapies using molecules that are familiar to the body. In the 1970’s Pauling published, with Scottish surgeon Ewan Cameron, two studies reporting that cancer patients, who had been told that there was no further orthodox treatment for them, given 10 grams of vitamin C per day, lived longer and had better quality of life. It is important to note that in these studies the vitamin C (intravenous at first, then oral) was used alongside surgery, radiotherapy and chemotherapy. The two studies at the Mayo Clinic which have been claimed to refute the Pauling/Cameron hypothesis, one used vitamin C alone as the treatment, and the other gave it after chemotherapy had finished, but most importantly, both studies only gave it for an average of 10 weeks.

At these doses the major role for vitamin C is supporting the immune system, which is known to be damaged by chemotherapy. Pauling and Cameron never recommended using vitamin C as the sole treatment; their papers referred to “supportive treatment”; this is what we aim to achieve here. Please be clear; there are as yet no clinical trials of this regime in cancer patients; it is not “evidence-based medicine”. There are two clinical trials of high-dose intravenous vitamin C going on at present, that we know about. See our separate info sheet about high-dose C, both intravenous and oral.

There are two compounds that appear to work synergistically with vitamin C against cancer:

  • Lipoic acid; a new, demonstrably more potent form of this, known as R-lipoic acid, is now available. In vitro (in the laboratory) this reduced the level of vitamin C needed to achieve an anti-cancer effect by about a factor of five.
  • Vitamin K has the same in vitro impact, and may also work on cancer in other ways. We therefore now recommend taking this as well.

##Vitamin D When I wrote about this in 1988 (Daylight Robbery; The importance of sunlight to health, Arrow Books) few took it seriously. Nowadays we have come to realise that we are nearly all deficient in the sunshine vitamin, and this is harmful. Preventing cancer is only one way that vitamin D is important; it appears to repair the communication between cells, which can make rogue cells return to normal. Studies are now ongoing to find out whether it helps in treating cancer; since it is virtually impossible to overdose, and it may well help, I advise taking it anyway.

Coenzyme Q10

There is some surprising anecdotal evidence that CoQ10, at the very high doses we propose here — 500mg per day — may be of real benefit in cancer. The reason for this would seem to lie in the nature of cancer cells, which cannot use oxygen as efficiently as healthy cells, and so use 10 times as much sugar for energy (more on this below). CoQ10 probably helps to repair this.

Zinc and B vitamins

Abram Hoffer got even better results than Pauling in a small, non-randomised study by adding B vitamins and zinc to the vitamin C. We advise that you do the same. There is a risk of harm if this is not done properly, though; see under Precautions below.

Interactions with chemo

Several researchers have suggested that antioxidant therapy (all the nutrients listed above are classed as antioxidants, although most of them have other benefits or other modes of action as well) may reduce the anti-cancer effects of chemotherapy and radiotherapy; this has generally been well-reported in the media, much more so than studies showing the opposite. Also, many of the well-reported studies have been laboratory studies, not clinical research on real people. The chemistry of this question is complex, but the bottom line, I believe, is provided by two review papers in 2007 & 2008 which considered all the available controlled clinical trials and concluded; “None of the trials reported evidence of significant decreases in efficacy from anti-oxidant supplementation during chemotherapy. Many of the studies indicated that anti-oxidant supplementation resulted in either increased survival times, increased tumor responses, or both”, and; “The majority (24) of the 33 studies included reported evidence of decreased toxicities from the concurrent use of antioxidants with chemotherapy.” The authors did warn that “lack of adequate statistical power was a consistent limitation”, but nonetheless, these are strong findings.


There are several “buts” to be aware of in all this; the first is that there is some evidence that low doses of antioxidants given infrequently or just once before treatment may indeed protect cancer cells against chemotherapy, while high doses do not. This is counter-intuitive, and concerning — firstly because some doctors have advised patients to take only low doses of antioxidant nutrients, and secondly because ⅔ of cancer patients take supplements, and most of their doctors do not know they are doing so. You need the advice of a doctor experienced in this area.

The second issue concerns the B vitamin folic acid (folinic acid, methyltetrahydrofolate); there is evidence that this can increase the toxicity of certain anti-cancer agents, as well as a suggestion in the literature that supplements of this might increase the risk of developing cancer. Therefore we do not recommend it unless there are specific reasons why it is needed, and no reasons not to take it.

Thirdly, vitamin A; supplements of this antioxidant vitamin caused side-effects in 1 in 4 subjects in one study; dry skin, dry mouth, anxiety and personality change. There is also evidence that heavy drinkers and/or smokers who also take vitamin A supplements have a greater risk of developing cancer, but that need not concern us here. In fact what we think of as vitamin A is only one member of a large family of similar molecules, and it is probably wiser to take a mixture of them all rather than lots of one molecule only. (The same is true of vitamin E.) You should be getting these in the colourful “plants” in your diet — see above.

Finally zinc; taking too much may be harmful. A study looking at men with prostate cancer found that taking over 100mg/day (which is pointless as well as harmful) could accelerate the growth of the cancer. We advise 25mg/day, and no more.


No sugar

In our view this is probably the most important single dietary change you should make.

Cancer cells depend on sugar, while normal healthy cells do not. Sugar is a growth factor for cancers, and avoiding it will starve the tumour. Ascorbic acid is a similar molecule to glucose, and is in fact made from glucose by all those animals that can make their own, which doesn’t include humans. Sugar may also keep vitamin C out of cells in general, and will also inhibit the normal metabolism of fats. All valid reasons to avoid it. And that includes high-sugar fruits and veg; get a booklet on glycaemic index and avoid the top half of the list.

Do not believe that sugary foods are a good way to regain lost weight either - it would be unhealthy fat that you gain, not functional weight.

What about fats?

For 50 years we have been told that all fat, or maybe saturated fat, is bad for us because it raises cholesterol, and so we are sold low-fat foods. It’s not true; in that time nobody has proved it, and there has been plenty of time. Trans fats, on the other hand, which only occur in processed foods, certainly are bad for the arteries.

Statins, which are given to lower cholesterol, do so, but that is probably not how they slightly benefit heart disease. It has now been claimed that they also prevent cancer, but that is probably an illusion too; having a higher cholesterol prevents cancer, and also leads to prescriptions for statins!

It is wise to avoid the chemicals in most meat by eating only organic, but our bodies, particularly our immune systems, need fats to build new cells. Eat good healthy organic meat, as well as wild or organic fish. Eggs, too, are an excellent source of healthy lipids (fats and oils). But most of your fats should come from — most of your food should be — plants, vegetables.


The food writer Michael Pollan summarises the basic good diet thus; “Eat food, not too much, mostly plants”. Every word in this counts. Eat means eat sit-down meals, don’t graze; food means not food-like substances, which it is so easy to consume; and plants means vegetables and fruit. Mostly vegetables though, especially if you are juicing them, so as to avoid the high sugar content of many fruits — and of some vegetables, such as carrots. Apart from carrots, take plenty of the colourful veg - red, yellow, purple etc as well as green.


  1. Cameron E, Pauling L. Supplemental ascorbate in the supportive treatment of cancer: Prolongation of survival times in terminal human cancer. Proc Natl Acad Sci U S A. 1976;73(10):3685-89.
  2. Cameron E, Pauling L. Supplemental ascorbate in the supportive treatment of cancer: re-evaluation of prolongation of survival times in terminal human cancer. Proc Natl Acad Sci U S A. 1978; 75 (9): 4538-42.
  3. Creagan ET, Moertel CG, O'Fallon JR, et al. Failure of high-dose vitamin C (ascorbic acid) therapy to benefit patients with advanced cancer. N Engl J Med. 1979;301(13):687-690.
  4. Moertel CG, Fleming TR, Creagan ET, Rubin J, O'Connell MJ, Ames MM. High-dose vitamin C versus placebo in the treatment of patients with advanced cancer who have had no prior chemotherapy. A randomized double-blind comparison. N Engl J Med. 1985;312(3):137-141.
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  6. Block KI, Koch AC, Mead MN, Tothy PK, Newman RA, Gyllenhaal C. Impact of antioxidant supplementation on chemotherapeutic efficacy: A systematic review of the evidence from randomized controlled trials. Cancer Treat Rev. 2007; 33(5): 407-18
  7. Block KI, Koch AC, Mead MN, Tothy PK, Newman RA, Gyllenhaal C. Impact of antioxidant supplementation on chemotherapeutic toxicity: A systematic review of the evidence from randomized controlled trials. Int J Cancer 2008; 123(6):1227-39
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Supplement regime

This is an illustrative programme of oral treatment. If we agree to increase the dose of vitamin C beyond this level, e.g. by the intravenous route, we will need to do a simple blood test called a G6PD before you start; an abnormality in this could mean that large quantities of vitamin C would be harmful to you.

Please report any side effects or problems to us so we can deal with them. When we meet again to discuss the results of the laboratory tests, we will be able to refine this further.

Treatment Breakfast Lunch Dinner Bedtime
Take dissolved in water, juice or other drink
Ascorbic acid powder - teaspoons ½ ½
inc - liquid, 1mg per drop 10 drops 10 drops
Open the capsules and mix contents into a protein-containing liquid (eg soup, broth) or food
Liposomal vitamin C - sachets, 1G 2 2
R Lipoic Acid - capsules, 150mg 1 2
Vitamin K2 - capsules, 120mcg 1 2
Vitamin D3 - capsules, 5000IU 2
Coenzyme Q10 - capsules, 500mg 1