In previous research investigating the effects of walnuts on cancer in mice studies it was found that even a small amount of walnuts given to animals with human breast cancer significantly slowed the rate of cancer growth, but the team was not able to identify the specific compound responsible for the effect.
In addition to slowing tumor growth the walnut containing diet also significantly decreased tumor incidence in animals genetically programmed to develop gland cancer. Examining the cancer related genes revealed changes in gene expression, especially in those involved in cell proliferation, mammary epithelial cell differentiation and cell death which lead to the hypothesis that walnut consumption may have the same effect on humans.
To test their hypotheses a two arm non-placebo clinical trial was conducted involving patients with breast lumps large enough for pathology biopsies and research. Patients were assigned either to a control group or to a walnut consumption group and after biopsy collection women began eating 2 ounces of walnuts everyday until the day of their follow up surgery.
Pathology confirmed that samples were collected from breast cancer lumps, and two weeks after their biopsy another surgery was conducted to collect additional samples to compare changes in gene expression between baseline samples for both groups. RNA sequencing expression identified 456 genes in the breast tumors, further analysis confirmed activation of pathways that promote apoptosis cell death, cell adhesion, and inhibition of pathways that promote cell proliferation as well as migration in samples from the walnut group.
Based on these findings the MCU researchers concluded that regular consumption of walnuts can suppress not only the growth but the survival of human breast cancers.
Walnuts are also a great source of fiber, omega-3 fatty acids, vitamins and minerals; 30 grams of organic walnuts can contain 20 grams of healthy fats, 5 grams of protein, 3.9 grams of carbs, 2 grams of fiber, and 20 mgs of calcium, along with vitamin B6, copper, manganese, magnesium, iron, and phosphorus. Walnuts may be on the high side of calorie and fats content, but the fats are monounsaturated and polyunsaturated fats which are considered to be healthier.
Walnuts have been shown to help to reduce the risk of heart disease, inflammation, oxidative stress, lower risk of gallstone disease, control blood sugar levels, lower blood pressure, support bone health, promote weight loss, improve brain function, increase the amount of beneficial gut bacteria, and support healthy aging. Even with all of these benefits it is still recommended to eat them in moderation due to the calorie and fat content.
