Keith I. Block, M.D. follow us read our blog

Ask Dr. Block

Recommended Protein Servings

Question: If you would, please clarify your recommended serving sizes of protein. In your book you recommend avoiding high-protein diets. As I interpret your table (pg 104) in the 1500 calorie column, the quantities you recommend seem to be what I would consider high-protein and I wonder if I’m misreading the chart. If 1 serving of fish is 4 oz, then 5 ½ servings would be the equivalent of 22 oz of fish (or 11 eggs) per day. The legume serving makes sense to me (2 ½ cups per day) but the fish & eggs seem proportionately high and seem to be not only high-protein but exceed the total calories. Also, would 2 Tbs of whey powder be approximately 1 serving?

Answer: The clue to answering your question lies in the advice given on page 102: “Be sure to eat a variety of protein foods over the course of a week.” The 5 ½ servings per day of protein in the 1500 calorie column is correct. I’d note that the diet on page 104 is...more

Whole Soy Products

Question: What are your thoughts on eating whole soy products (tofu, miso, edamame) for breast cancer patients? I’ve read that people who have consumed soy products their entire life can continue to do so, but those who have not should limit their soy consumption. Also, there seems to be a distinction between pre- and post-menopausal breast cancer patients?

Answer: I feel that breast cancer patients can use whole soy foods as a part of an overall healthful, mostly vegetarian diet. We recommend eating soy foods two to three times per week; while they are good protein sources, they are also rather high in fat, which...more

Antioxidant Foods and Chemotherapy

Question: Does taking antioxidants, for example blueberries, while on a chemo regime interfere with the effects of chemo?

Answer: Though much has been written in the mainstream media about potential concerns associated with the use of antioxidants during chemotherapy, these concerns have been limited to the use of antioxidant supplements, and not relevant to antioxidant-rich food. At the Block Center, we believe...more

Watermelon and Prostate Cancer

Question: Can you comment on watermelon, whether it is good or bad to help with prostate cancer?

Answer: This is a timely question! Watermelon is a wonderful summer fruit, and a truly healthy treat. The part of watermelon that’s most likely to help with prostate cancer is...more

Flaxseed during Breast Cancer Treatment

Question: Does flaxseed interact with Aromasin and similar medications?

Answer: Aromasin, Arimidex and Femara are all medications called “aromatase inhibitors.” They are used in breast cancer treatment for women who are post-menopausal and whose tumors are...more

Whey Protein

Question: I understand why dairy is not part of a cancer prevention diet. Can you explain why whey protein is okay?

Answer: Milk has two proteins: casein (approximately 80%) and whey (approximately 20%). Whey is the only dairy product we recommend at the Block Center. Casein has been found to increase inflammation...more

Diet Sodas and Aspartame

Question: I'm drinking several Diet Cokes per day and know the aspartame can't be good for me but I'd like to hear The Block Center's take on it. Does it increase insulin secretion as does refined sugar?

Answer: Aspartame is a non-nutritive sweetener (no substantial calories) that is made from two amino acids, L-phenylalanine and L-aspartic acid, and the alcohol, methanol. The main reason...more

Gastric Cancer: Diet and Xeloda

Question: In Life Over Cancer, you recommend a modified macrobiotic diet or low fat, few animal proteins, high vegetable, no refined carbs, to best make the body inhospitable to cancer. You cite the benefits of the Japanese diet. Is this true with gastric cancer, too? I understand that gastric cancer is prevalent in Japan.
Also, you say that antioxidants taken during treatment on Xeloda enhanced treatment effectiveness. Would this be expected for gastric cancer treatment with Xeloda as well?

Answer: Gastric cancer occurs at higher rates in Japan and Korea than in the United States. It also occurs at high rates in impoverished populations in...more


Question: Could you recommend a few cookbooks that keep your food guidlines?

Answer: There are many excellent cookbooks that translate the good science, as discussed in Life Over Cancer, into truly good food. Therefore, the titles mentioned below are...more

Grape Seed Oil

Question: Is grape seed oil a good oil like olive oil and canola oil?

Answer: Grape seed oil has a light taste and very high smoking point, which makes it great for stir-frying. However, it has a very different fatty acid profile than...more

Fish Oil

Question: What are the side effects from taking the fish oil supplement ArcticBlox?

Answer: “ArcticBlox” is the enterically-coated fish oil supplement formulated specifically by the Block Center. Enteric coating is important because many people experience...more

Vitamin C during Chemotherapy

Question: Does vitamin C therapy play a beneficial role during chemotherapy treatment?

Answer: Yes, it can. We’ve been using Vitamin C at the Block Center for some time. However, all antioxidants are affected by the individual that’s receiving it. Therefore, I don’t...more


Question: I heard you speak recently and think you said that treatment shouldn’t end even when a doctor tells a patient they’re in remission. Can you please explain what you meant by this?

Answer: Cancer is not just want you can see, but it is also what you cannot see. It is the invisible disease that comes back to haunt patients and thus...more