For over twenty years there has been a vocal minority in Oncology circles encouraging Oncologists to take glucose out of the diet of cancer patients as a way of depriving the cancer cell of its nutrition of choice. This theory is supported by abundant laboratory evidence that cancer cells use glucose preferentially; the PET scan after all measures preferential glucose uptake by the cancer cell. When Dr. Stark was Medical Director at Cancer Treatment Centers of America, he teamed up with Dr. George Blackburn from Harvard Medical School to look at the effects of feeding patients with metastatic cancer diets very low in carbohydrates, almost completely eliminating free glucose in the diet. The experiment didn’t last very long because patients fed this diet ad lib were unable to maintain their weight. Glucose makes food palatable. Fat provides the most efficient source of calories, 9 calories per gram versus 4 for glucose and protein, but a high fat diet produces ketosis, which causes a change in taste perception and loss of interest in food.
In a recent review article in Nutrition and Metabolism, two German authors revisit the low carbohydrate diet. Dr. Stark can provide the article if you fill out the form to the right of this page. They review animal experimental data and human studies and conclude that changing food intake in favor of a so-called ketogenic diet (high fat content, producing ketosis) can inhibit tumor growth. In particular, brain tumor patients were studied and lived longer on a ketogenic diet. The problem was that they lost so much weight that their life styles were affected. They re-challenge the Oncology world to come up with an iso-caloric way of doing this and restudying this intriguing concept. At a time when cancer treatment is focused on altering signals to cancer cells using exploiting genetics differences between normal and malignant cells, dietary alteration would provide a non-drug adjunct which could work synergistically with this new class of drugs.
Update from 2020: the latest word is that tiny amounts of glucose are required for properly cellular signaling in cancer cells. Depriving the cells of glucose doesn’t starve them, it interrupts signals given within the cell. Conversely calcium in the cells acts to poison the signals. Scientists are currently working on a way to add calcium and starve the cell of sugar at the same time. This work is highly speculative and is being done at the cellular levels in the laboratory. It is not clear whether it ever will see the clinic.