There have been many dietary recommendations to reduce the risk for cancer throughout the years. Most include a reduction in sugar, processed foods, alcohol, and food allergens. This study stems from the federally funded Women’s Health Initiative which is a long-term health study launched back in 1993. The study enrolled women in their 50’s, 60’s and 70’s at the time it started.
About 20,000 women were coached to change their diets for at least 8 years. Women were asked to reduce their total fat intake and to increase their intake of fruits, vegetables and grains. A comparison study of 30,000 women were asked to continue their normal diet. The results showed that women in both groups were diagnosed with breast cancer, but the women who changed their diets had a 21% lower risk of dying from breast cancer.
Even though this study may be significant in the reduction of deaths from breast cancer, it goes against the most recent research about eating plenty of healthy fats such as fish, olive oil, avocados and other plant based oils. Remember that this study was conducted in the 1990’s when the low-fat boom was at its peak. A lot has changed since then…healthy fats=good; refined carbs and sugars=bad! Notice I said “good fats”. As mentioned in this article, lollipops and lentils are both low fat, whereas avocados and butter are both high fat. The women in this study were asked to achieve a low-fat diet through eating more fruits, veggies and whole grains which would increase their fiber and nutrient intake.
Also, the women in the study who modified their diet lost on average about 3% of their starting body weight. Obesity is a risk factor of breast cancer so shedding weight may have also reduced cancer risk.
I believe weight reduction has a bigger impact on breast cancer risk reduction than we once thought. Dr. Ruth Patterson, Ph.D professor and cancer researcher at UCSD was involved in a recent study of 2500 breast cancer survivors. In this study, WHAT you ate was not as important as WHEN you ate. The results showed that women who fasted at least 13 hours had a reduced recurrence of breast cancer by 40%!!! Fasting also lowered the risk of diabetes, non-alcoholic fatty liver disease and gastroesophageal reflux.
The concept behind this is that women that are overweight or obese produce too much insulin. Estrogen is stored in adipose (fat) tissue. Both estrogen and insulin are growth factors, which means it increases the growth rate of tumors. We also know that fat causes more inflammation. So you can see the effect of this trio…more estrogen, more insulin and more inflammation. Insulin also decreases sex hormone binding globulin (SHBG) which allows estrogen and testosterone to be unbound and more freely available to again increase estrogen and inflammation.
Intermittent fasting is becoming very popular for many health conditions. If weight loss is your goal then I would increase your fasting times so that your eating window is 5-6 hours. I know…thats like 17-18 hours fasting, so move the fasting times by 1 hour and try it slowly. If that is difficult, then fast for at least 13-14 hours and stop eating earlier at night. In the study, women fasting for 13 hours may not have lost weight but they did reduce inflammatory markers if they stopped eating earlier.
My opinion, is not to reduce fats but to increase fruits and vegetables and eat small portions of whole grains. Aim to eat dinner early and then wait a full 13-14 hours (or more) before eating breakfast. Avoid smoking and alcohol and exercise regularly. Don’t forget a good night’s sleep. Sleep repairs a lot more damage when fasting and can help DNA repair and “autophagy”-clearing away damaged cells, which has the potential to increase further inflammation. Work towards these daily goals and your breast cancer risk as well as other diseases will be significantly reduced.
Stephens, G. “Delay, don’t deny: Living an intermittent fasting lifestyle.” 2017.