For many breast cancer survivors, the end of active treatment does not mark the end of physical and mental challenges. Memory lapses, difficulty concentrating, and persistent exhaustion can linger for years, interfering with daily routines. Researchers at the UCLA Health Jonsson Comprehensive Cancer Center have identified a potential remedy in a naturally occurring molecule called oxaloacetate. Early results from a small clinical trial suggest this supplement may help clear the cognitive fog that often follows cancer therapy.
Improvements in Thinking and Energy
The study involved 18 women diagnosed with early-stage breast cancer between one and five years prior to the trial. All participants reported significant cognitive difficulties at the start of the research. On average, the women were 50 years old, and most had undergone chemotherapy. Nearly 90 percent were still receiving endocrine therapy during the study period.
Participants took 500 milligrams of oxaloacetate twice daily for eight weeks. The goal was to see if boosting levels of this molecule, which plays a key role in cellular energy production, could alleviate symptoms. By the end of the trial, 16 women had completed the full regimen. Every participant who finished the study reported noticeable improvements in their thinking abilities.
Standardized tests confirmed these subjective reports. Researchers observed gains in processing speed, memory, and executive function, which includes the ability to plan, organize, and maintain focus. The improvements were not limited to mental tasks. Participants also reported significantly less fatigue and better physical functioning, suggesting the supplement may help combat the mental exhaustion that makes everyday activities difficult.
Understanding the Biological Mechanism
Cognitive difficulties affect an estimated 15 to 25 percent of breast cancer survivors. While often referred to as “chemo brain,” the condition is complex. It is not caused by chemotherapy alone. The cancer itself, hormonal changes, inflammation, and other biological factors likely contribute to the problem.
Dr. Patricia Ganz, the study’s first author and a distinguished professor at UCLA, noted that effective treatments for this condition remain scarce. “Cancer-related cognitive impairment can persist long after treatment ends and can have a significant impact on a person’s daily life, yet we still have very few effective treatments for it,” Ganz said.
Oxaloacetate attracted the research team’s attention because it is involved in both energy production and the regulation of glutamate, a chemical messenger in the brain. Inflammation associated with cancer and its treatments may disrupt glutamate signaling and interfere with how brain cells generate energy. By providing additional oxaloacetate, the researchers hoped to support these biological processes and restore normal brain function.
Next Steps for Clinical Research
The results were promising, but the study had limitations. The sample size was small, and there was no placebo group to compare against. Without a control group, it is impossible to determine if the improvements were caused by the supplement or other factors. The scientists emphasized that these findings are preliminary and require confirmation through larger, more rigorous trials.
Oxaloacetate was generally well tolerated during the eight-week period. The most common side effects were digestive issues, including indigestion, bloating, constipation, diarrhea, and nausea. Two women stopped taking the supplement due to these gastrointestinal symptoms. No serious adverse events were recorded.
To build on these initial findings, the UCLA team is preparing a randomized, placebo-controlled phase II clinical trial. This study is expected to begin enrolling participants in late 2026. The researchers also continue to conduct preclinical research in mice to better understand how oxaloacetate affects the body and brain. The research received partial financial support from the Breast Cancer Research Foundation and the National Cancer Institute.
Source: ScienceDaily
