New research suggests eating a high-fat diet during puberty could speed up the development of breast cancer and even increase risk of diagnosis.

Before breast cancer appears, there are precursor changes in the breast tissue such as increased cell growth. These changes can occur in adolescence and continue into adulthood, they run the risk of becoming precancerous lesions or breast cancer tumors, a Michigan State University's Breast Cancer and the Environment Research Program news release reported.

A high-fat diet causes a "distinct gene signature" in tumors consistent with basal-like cancer, which can be more dangerous than other breast cancers.

"This is very significant because even though the cancers arise from random mutations, the gene signature indicating a basal-like breast cancer shows the overarching and potent influence this type of diet has in the breast," Sandra Haslam, physiology professor in MSU's College of Human Medicine and one of the lead investigators of the project, said. "Cancers of this type are more aggressive in nature and typically occur in younger women. This highlights the significance of our work toward efforts against the disease."

The researchers looked at puberty-aged people of all weights, so the link was not related to weight gain.

"This shows the culprit is the fat itself rather than weight gain," Richard Schwartz, microbiology professor and associate dean in the College of Natural Science said.

The team suggested diet high in animal fats early in life could be harmful even if a healthier diet was implemented later in life.

"Overall, our current research indicates that avoiding excessive dietary fat of this type may help lower one's risk of breast cancer down the road," Shwartz said. "And since there isn't any evidence suggesting that avoiding this type of diet is harmful, it just makes sense to do it."

The research was funded with a $2.3 million federal grant from the National Institute of Environmental Health Sciences and the National Cancer Institute.