Research from the University of Florida suggests that glucosamine, a popular joint health supplement, may increase the risk of dementia progression in individuals with mild cognitive impairment.
Many older adults turn to glucosamine to manage joint discomfort associated with aging. However, a recent study conducted by researchers at the University of Florida indicates that for individuals with mild cognitive impairment, the supplement could be linked to a faster progression toward Alzheimer’s disease.
The study, published in Nature Metabolism, investigated the effects of glucosamine on dementia risk and mortality by analyzing medical records of patients with mild cognitive impairment. The researchers also tracked laboratory mouse models and examined brain tissue from both healthy individuals and those affected by Alzheimer’s disease.
Senior author Ramon Sun, Ph.D., a professor of biochemistry and molecular biology at the University of Florida, explained the significance of glycosylation, a natural process where brain cells attach small chains of sugar to proteins. “You can think of these sugar chains as the labels and fittings on a machine part — they help a protein fold correctly, get shipped to the right place in the cell, and connect with its partners,” he told Fox News Digital. “The right amount is essential.”
Neil Levin, senior nutrition education manager at Now, a manufacturer of glucosamine supplements, described glucosamine as a naturally occurring compound composed of sugar and an amino acid group that serves as a fundamental structural building block in the body. He noted that glucosamine is concentrated in cartilage, the connective tissue that cushions joints, and is a component of larger molecules that contribute to cartilage’s strength, elasticity, and ability to retain water.
According to Sun, the body has an internal “checkpoint” that regulates the production of sugar chains. However, supplemental glucosamine bypasses this regulation, akin to a delivery truck pulling directly to a loading dock, thereby increasing the supply of raw materials used to create these sugar chains.
In their analysis, the researchers focused on thousands of dementia patients, including those with Alzheimer’s disease, and narrowed the group to individuals taking glucosamine. They found that while glucosamine did not alter the mortality risk for those with mild cognitive impairment, it did increase the likelihood of progressing to dementia by 25%. Conversely, among individuals already diagnosed with dementia, glucosamine users exhibited a higher mortality rate compared to non-users.
The researchers also examined brain tissue to understand the underlying mechanisms of this association. “We found an excess of sugar chains on proteins in the Alzheimer’s brain,” Sun stated. Many of these proteins are crucial for nerve cell communication, but the excess sugar chains may disrupt their functionality. Sun likened this effect to coating a key in too much wax — the key remains the same, but it no longer fits the lock properly.
In addition to human studies, the researchers conducted experiments on mice to observe how glucosamine was processed in healthy brains compared to those affected by Alzheimer’s-like disease. “In our experiments, normal mice given glucosamine showed no increase in these sugar chains and no change in a memory test,” Sun noted. “However, in mice with Alzheimer’s-like disease, where the production line was already running too hot, glucosamine further increased the sugar chains and worsened performance on a memory test.”
While the study relied on medical records, Sun cautioned that these records may not capture every supplement a patient is taking. “Health records tell us what was documented, not everything a person took,” he explained. “Over-the-counter supplements are not always recorded, and records don’t reliably capture dose, brand, or how consistently someone took it.”
Levin also pointed out that glucosamine users may differ in various factors such as arthritis, pain, mobility, frailty, and medication use. The records did not specify the exact supplement, dosage, duration, or consistency of use.
“The finding should therefore be treated as a safety signal that warrants controlled human research, but it did not — could not — reach a conclusion that glucosamine causes Alzheimer’s disease,” Levin stated. The researchers emphasized the need for a well-designed, double-blind clinical trial to evaluate the impact of glucosamine on cognitive decline in patients with dementia.
“For now, the evidence isn’t strong enough to recommend any supplement for slowing Alzheimer’s disease, which is why conducting this research properly, including the clinical trial we’ve called for, matters,” Sun said. It is important to note that the study did not examine cognitively healthy individuals and does not suggest that glucosamine poses a risk to those who take it for joint health.
Sun highlighted the differences between a brain affected by dementia and a healthy brain, stating, “A brain affected by dementia and a healthy brain are different biological environments, and we shouldn’t assume a supplement behaves the same way in both.” He advised consulting with a doctor before starting or stopping any supplement.
“If you or a family member has a diagnosis of cognitive impairment or dementia and takes glucosamine, it’s reasonable to bring it up at the next visit, as part of an ordinary conversation about what’s in the medicine cabinet,” Sun recommended.
This study underscores the complexities of dietary supplements and their potential effects on cognitive health, warranting further investigation to clarify the relationship between glucosamine and dementia risk, according to Fox News Digital.