A friend recently contacted me to say that she had been diagnosed with breast cancer and would need chemotherapy – and to ask if I had any advice on what she could do nutritionally to increase her chances of a successful outcome. .
It’s a tough question to answer because while some of the evidence around diet and cancer is fairly well-established (such as the benefits of eating a Mediterranean diet, see below), other approaches, such as intermittent fasting, are much more valuable. . controversial.
But new research suggests this could also be helpful in the right patients.
There are different types of intermittent fasting, ranging from time-restricted eating – where you limit your food intake to a certain number of hours per day – to the 5:2 diet, where you reduce your calories on two or more days per week. .
Early evidence for the latter’s potential benefits in preventing breast cancer emerged from a University of Manchester study in 2013. The researchers took a group of 115 middle-aged women with a family history of breast cancer, which put them at increased risk on breast cancer. the sickness.
There are different types of intermittent fasting, ranging from time-restricted eating – where you limit your food intake to a certain number of hours per day – to the 5:2 diet, where you reduce your calories on two or more days per week. (Stock Image)
The women were randomly assigned to eat a standard low-calorie diet, or for two days a week, half were asked to eat just 650 calories from a low-carb Mediterranean diet (i.e. intermittent fasting).
After eight weeks of this regimen, the intermittent fasting group lost an average of 6kg – almost twice as much as the daily dieters.
Significantly, they also saw much greater improvements in their insulin sensitivity, a measure of how much insulin your body needs to produce to lower your blood sugar levels.
This is important because high levels of insulin are thought to help promote cancer growth. The same researchers published a study in 2016 showing that not only did a month of intermittent fasting lead to weight loss, but breast biopsies showed that just over half of women showed changes in gene activity in their breast tissue, suggesting they were less likely to do so. become cancerous.
Aside from intermittent fasting’s impact on insulin levels, it can also help fight cancer by increasing the effectiveness of our T cells, an essential part of the immune system. This is evident from a new study from the Van Andel Research Institute in Michigan, USA, published in the journal Immunity.
The study, which was based on mice, showed that ketones, a type of fuel produced by our bodies in response to intermittent fasting, help recharge T cells, making them more effective at neutralizing cancers. So there’s some evidence that intermittent fasting can boost your immune system and help reduce your risk of developing certain cancers, including breast cancer. And if you have cancer, this can soften the effects of treatment.
Although few human studies have been conducted, I was struck by recent research presented at the European Society for Medical Oncology conference by Charité University Medicine Berlin.
Aside from intermittent fasting’s impact on insulin levels, it can also help fight cancer by increasing the effectiveness of our T cells, an essential part of the immune system. This is evident from a new study from the Van Andel Research Institute in Michigan, USA, published in the journal Immunity (Stock Image)
The study involved 106 women who had been diagnosed with early-stage breast cancer and were about to undergo chemotherapy.
Half of them were asked to follow a low-calorie diet consisting largely of vegetable juices and vegetable broths for two days before chemotherapy and then for 24 hours afterwards.
Surprisingly, despite consuming fewer calories than normal, the women who followed the fasting regimen reported much less fatigue and a much greater sense of well-being after chemotherapy than the control group, and no side effects were reported.
In addition to increasing ketone levels, short-term fasting also lowers glucose levels in the blood, which makes it harder for cancers to grow and can make them more vulnerable.
Although encouraging, the study was too short to demonstrate whether short-term fasting has a positive impact on long-term survival.
It’s still so early for this study that when it comes to chemotherapy, intermittent fasting isn’t something I would recommend you try outside of an actual clinical trial.
Instead, as I said to my friend with breast cancer, I think it would be safer to eat a Mediterranean diet, one rich in fatty fish, olive oil, nuts, fruits, vegetables and legumes. Not only has this been shown in studies to reduce the risk of developing cancer, but a recent study found that it can also make chemotherapy more tolerable.
The study from the University of Rochester Medical Center in the US found that cancer patients who followed a Mediterranean diet for a few months reported much less fatigue after chemotherapy than those who followed a ‘usual care’ program.
Interestingly, the diet’s beneficial effects seemed to come, at least in part, from boosting the patients’ mitochondria, the little batteries in all our cells that power them, especially those that supply T cells.
At this time, the Mediterranean diet is not routinely suggested to people about to undergo chemotherapy, but it is something I would recommend.