In a potentially game-changing discovery for Alzheimer’s research, scientists have found that a common kitchen spice may enhance cognitive abilities.

The team from Taiwan investigated the effects of sodium benzoate, a crucial compound that forms when the body breaks down cinnamic acid, which is present in cinnamon—a popular flavoring and preservation ingredient.

The study involved participants with mild Alzheimer’s who took capsules containing either 750 milligrams or 1,000 milligrams of sodium benzoate. They experienced notable reductions in amyloid plaques, deposits of amyloid-beta protein that damage brain tissue and are associated with impaired memory and executive functions.

Among those who received these doses, individuals who had higher initial levels of amyloid-beta 1–42 in their blood showed more significant cognitive improvements over 24 weeks compared to those with lower initial levels.

Participants given a placebo did not exhibit similar improvements. Sodium benzoate also proved to be safe and well-tolerated, with side effects comparable to the placebo group.

Cinnamic acid has been noted for its antioxidant properties by alleviating oxidative stress, reducing inflammation, aiding insulin processing, preventing DNA changes that could lead to cancer, and activating enzymes that both break down fats and inhibit the formation of new fat cells, thereby assisting with obesity management.

New Alzheimer’s treatments that target the disease’s characteristic amyloid-beta proteins can slow cognitive decline, supporting a long-held theory of its cause. However, these intravenous therapies carry risks of brain swelling and bleeding, alongside high costs and demanding infusion schedules.

The researchers concluded: ‘Due to its superior safety and convenient administration, sodium benzoate has the potential to be a new [amyloid-beta]-reducing medication for AD.’

Scientists zeroed in on amyloid-beta as a central suspect in the cause of Alzheimer’s disease in the early 1990s.

The toxic protein most severely affects regions of the brain that are crucial for memory and higher-order thinking. 

It accumulates as a person ages, with Alzheimer’s primarily affecting seniors 65 and older. The disease is estimated to afflict about 7 million Americans. 

Scientists recruited 149 people who ranged in age from 50 to 100 and had been diagnosed with mild early Alzheimer’s disease.

All of them showed elevated levels of amyloid-beta in the blood and exhibited mild cognitive decline based on clinical scoring.

One group received a placebo, while the other three groups received different daily doses of sodium benzoate at 500 milligrams, 750 milligrams or 1,000 milligrams.

These are pharmaceutical doses. While sodium benzoate is a metabolite of cinnamon, the amount found naturally in the spice is far lower than the therapeutic doses used in this study. 

Researchers assessed the cognitive function of each participant throughout the 24-week study using a standardized test called the Alzheimer’s Disease Assessment Scale-Cognitive Subscale.

The standard tool used in clinical trials for Alzheimer’s disease indicates that a lower score correlates with better cognitive performance. 

Before the trial began and after it concluded at 24 weeks, blood samples were collected from the participants.

Treatment with the two higher doses (750 mg and 1,000 mg per day) significantly improved cognitive function compared to a placebo.

The study further revealed that the treatment directly impacted Alzheimer’s-related biomarkers. 

At these effective doses, sodium benzoate significantly reduced blood levels of amyloid-beta peptides, specifically amyloid-beta 1–40 and total amyloid-beta.

A crucial discovery was that patients who started the trial with higher baseline levels of amyloid beta-42 in their blood experienced greater cognitive improvement from the two most effective benzoate doses.

This same relationship was not seen in the placebo group, indicating the effect was specific to the cinnamon-derived treatment.

Their findings were published in the journal Translational Psychiatry.  

The study’s limitations include a moderate sample size that may have limited its statistical power, as well as a 24-week duration, which leaves the long-term effects unknown. 

Researchers added that the findings in a Han Taiwanese population may not be generalizable to other groups.

Additionally, while doses of 750 mg and 1000 mg were effective, even higher doses may produce different results. 

And the study also could not confirm the mechanism by which the cinnamon metabolite works.

Previous research has also suggested a link between the substance in cinnamon and benefits for Alzheimer’s patients. 

Dr Kalipada Pahan, a neuroscientist at Rush University in Chicago, reported in 2016 that cinnamon may improve learning and memory by acting as a slow-release form of sodium benzoate. 

In mouse studies, cinnamon consumption helped poor learners by reversing specific detrimental changes in the hippocampus, the brain’s memory center. 

And in 2023, researchers from China and Brazil conducted an analysis of available research and concluded that sodium benzoate can reduce levels of amyloid-beta peptides in the blood of patients with Alzheimer’s. 

They also found that the compound hampered the buildup of tau. In Alzheimer’s, tau proteins inside neurons become tangled, leading to cell death. By preventing these ‘tangles’ from forming, cinnamon could protect brain cells.