Flaxseeds may reduce risk of BREAST CANCER, study suggests

Flaxseeds – usually sprinkled on acai bowls or mixed in smoothies – may reduce the risk of developing breast cancer, a study suggests.

Researchers in Nebraska and Canada gave female mice a solution of flaxseed oil, which contains lignans, a compound found in fiber-rich foods like grains, seeds, nuts, and drinks like coffee. 

They found it triggered a relationship between the gut microbiome and mammary gland microRNAs (miRNAs), which are linked to breast cancer cell growth. 

Rodents given the flaxseed oil were less likely to develop breast cancer.

In the new study, the lignans in flaxseed oil were shown to positively reduce the chance of cancer cells growing in the mammary glands, leading to a lower likelihood of developing breast cancer

The researchers said that these findings could lead to new dietary recommendations for preventing breast cancer, the most common cancer in the US, affecting nearly 300,000 American women ever year. 

Dr Elena M Comelli, study author and assistant professor in the Department of Nutritional Sciences at the University of Toronto, said: ‘If these findings are confirmed, the microbiota becomes a new target to prevent breast cancer through dietary intervention.’

Past research has shown that lignans have anti-inflammatory properties and cause the body to produce less estrogen, leading to a lower risk of breast cancer. 

The researchers fed a solution of flaxseed lignans to female mice for three weeks and found that they triggered a reaction in the cecal gut, a pouch-like part of the colon that separates the small and large intestine. 

When the flaxseed enters the gut microbiome – a network of bacteria that live in the digestive tract and help us fight infections and regulate appetite – it sends signals to miRNAs in the mammary glands that lead to a lower chance of developing breast cancer cells. 

Dr Jennifer Auchtung, journal author who worked on the paper and assistant professor at the University of Nebraska – Lincoln, said: ‘The gastrointestinal microbiota plays an important role in modifying many components of our diet to impact human health.’

‘In this study, we found correlations between diets enriched in flaxseed, cecal microbiota composition and miRNA profiles in the mammary gland that regulate many pathways, including those involved in cancer development.’

‘This preliminary study supports further research into the role that the microbiota plays in dietary approaches to reduce risk factors associated with disease.’

Lignans have been shown to cause women who have gone through menopause to produce less active forms of estrogen, which is believed to reduce the risk of breast cancer. 

Other grains like barley, buckwheat, millet, oats, rye, and wheat also contain high levels of lignans. They are also plentiful in other nuts and seeds, as well as drinks like coffee, tea, and wine.

The new study affirms other recent findings suggesting that flaxseed reduces cancer risk.

A 2021 study of over 400 people published in the journal Clinical Nutrition Research, for example, found that lignans resulted in a lower chance of breast cancer. 

Some research has also suggested that flaxseeds reduce the growth rate of prostate cancer cells. 

Flaxseed has also been shown to treat digestive distress, such as constipation, and lower LDL (bad) cholesterol, reducing the risk of diabetes and heart disease. 

Flaxseed is rich in polyunsaturated fat, fiber, manganese, magnesium, zinc, vitamin B6, iron, and folate, all of which improve metabolism, digestion, and immune health. 

Breast cancer is the most common form of cancer in the US, affecting nearly 300,000 women and almost 3,000 men every year. According to the National Cancer Institute (NCI), an estimated 43,000 Americans will die from breast cancer this year

The researchers cautioned that the findings are preliminary, and more research is needed. 

The study was published Thursday in the journal Microbiology Spectrum.