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Both the Women’s Intervention Nutrition Study and the Women’s Health Initiative study showed that women randomized to a lower-fat diet enjoyed improved breast-cancer-free survival. But, wait a second. What about the Women’s Healthy Eating and Living Study, where women with breast cancer were also randomized to drop their fat intake down to 15 to 20 percent of calories, yet after seven years there was no difference in breast cancer relapse or death? Any time you get an unexpected result, you always have to question whether people actually followed through with the instructions. Like if you randomized people to a stop-smoking group, and they ended up with the same lung cancer rates as the group not instructed to stop smoking, one likely explanation is that the group told to stop smoking didn’t actually stop. In the Women’s Healthy Eating and Living Study, both the dietary intervention group and the control group started out at about 30 percent of calories from fat. Then, the diet group was told to drop down to 15 to 20 percent. And by the end of the study, they dropped from 28.5 percent fat all the way down to 28.9 percent fat! They didn’t change at all. No wonder they didn’t experience any breast cancer benefit.
But even if you include that flawed study, and put all the trials together on the effect of lower-fat diets on breast cancer survival, you see a reduced risk of breast cancer relapse and a reduced risk of death. Conclusion: Going on a low-fat diet after a breast cancer diagnosis can improve breast cancer survival by reducing risk of cancer recurrence. And now, perhaps, we know why: by targeting metastasis-initiating cancer cells through the fat receptor CD36, which I covered in my last two videos.
We know that the cancer-spreading receptor is upregulated by saturated fat. Is there anything in our diet that can downregulate it? Broccoli. Broccoli appeared to decrease CD36 expression by as much as 35 percent, but that was in mice. But of all fruits and vegetables, cruciferous vegetables like broccoli were the only ones associated with significantly less total cancer risk, and not just getting cancer in the first place. Those with bladder cancer who eat broccoli appear to live longer than those who don’t. Those with lung cancer who eat more cruciferous veggies appear to survive longer as well. For example, one year out, about 75 percent of lung cancer patients eating more than one serving of cruciferous vegetables a day were still alive, whereas, by then, most who had been getting less than a half serving a day were already dead––killed off by their cancer.
Ovarian cancer. “Cruciferous vegetable…[intake] signiﬁcantly favor[ed] survival”, whereas “a survival disadvantage was shown for meats.” Milk also appeared to double the risk of dying. Here are the survival graphs. Eight years out, for example, about 40 percent of ovarian cancer patients who averaged meat or milk every day were dead, compared to only about 20 percent who just had meat or milk a few times a week at most.
Now, it could just be that the fat and cholesterol in the meat increased circulating estrogen levels, or because of meat’s growth hormones, or all the carcinogens. And galactose, the sugar naturally found in milk, may also be directly toxic to the ovary, and dairy has got all the hormones too. However, the lowering of risk with broccoli and the increasing of risk with meat and dairy are also consistent with the CD36 mechanism of cancer spread we’ve been talking about.
So, how about putting it to the test for patients with advanced pancreatic cancer, given pulverized broccoli sprouts or a placebo. “Compared to those [in] the placebo group, the [average] death rate was lower in the [broccoli] group…”. After a month, 18 percent of the placebo group was dead, but none in the broccoli group. By three months, another quarter of the placebo group had died, but still not a single death in the broccoli group. And by six months, 43 percent of the remaining patients in the placebo group were dead, along with the first 25 percent of the broccoli group. Unfortunately, the patients knew which group they were in because they were evidently getting broccoli burps which gave it away, so you can’t discount the placebo effect. And they weren’t even properly randomized, since many of the patients refused to participate unless they were placed in the active treatment group––which is understandable, but it makes for a less rigorous result. But hey, a little broccoli can’t hurt. And it’s the no downsides that leads to “Advising Women Undergoing Treatment for Breast Cancer,” for example, to include the “liberal culinary use of cruciferous vegetables…” And the same for reducing saturated fat.
“Is it time to give breast cancer patients a prescription for a low-fat diet?” “Although counseling women to consume a healthy diet after breast cancer diagnosis is certainly warranted for general health,” read an editorial in a journal of the National Cancer Institute, “the existing data still fall a bit short of proving this will help reduce the risk of breast cancer recurrence and mortality.” But what do you have to lose? After all, it’s still certainly warranted for general health.
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