People with Alzheimer’s disease or mild cognitive impairment have low glutathione levels. Oxidative stress is a biological phenomenon that manifests when highly reactive molecules produced during metabolism accumulate in the body, damaging DNA and cells and driving a wide of range of chronic diseases, including Alzheimer’s disease and mild cognitive impairment. The body produces antioxidant molecules to counter the effects of oxidative stress, but its capacity to produce the molecules varies based on a person’s lifestyle and overall health. A recent meta-analysis reveals that people with Alzheimer’s disease and mild cognitive impairment have low brain and blood levels of the antioxidant molecule glutathione.

Glutathione is a potent antioxidant compound produced in the body’s tissues, particularly those that experience high levels of oxidative stress, such as the eyes, liver, and brain. Glutathione scavenges harmful reactive molecules, thereby preventing damage from oxidative stress, but evidence suggests glutathione levels decrease with aging, contributing to many aging-related diseases.

The authors analyzed data from studies in which researchers measured glutathione levels in the brains (eight studies) or blood (33 studies) of people with Alzheimer’s disease or mild cognitive impairment and compared those levels to healthy people. They conducted a sub-analysis of the data collected in the brain studies that used an advanced measurement technique called MEGA-PRESS, which may be more accurate than traditional techniques.

They found that when using traditional measurement techniques, researchers did not observe differences in brain glutathione levels among people with Alzheimer’s disease or mild cognitive impairment versus healthy people. However, when researchers used the MEGA-PRESS technique, brain glutathione levels were indeed lower in people with Alzheimer’s disease or mild cognitive impairment. The data also revealed lower blood glutathione levels in both Alzheimer’s disease and mild cognitive impairment, compared to healthy people.

These findings suggest that people with Alzheimer’s disease or mild cognitive impairment have lower levels of glutathione in their brains and blood. Interestingly, some dietary compounds or lifestyle behaviors may increase endogenous glutathione production. For example, evidence suggests that sulforaphane, a bioactive compound derived from broccoli and broccoli sprouts, increases glutathione in the brain. In addition, sauna use, which induces mild hyperthermia, increases the production of heat shock proteins, which are involved in glutathione maintenance and activity.

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