Protein Supplements and Neurodegenerative Disorders: Is There A Link?
A recent study published in the Journal of Nutrition Research found that protein supplements may increase the risk of developing Alzheimer’s disease (AD) or other neurodegenerative disorders. The study was conducted by researchers from the University of California San Francisco (UCSF). They looked at data collected on over 6,000 men and women between the ages of 50 and 79 years old. The participants were recruited between 1990 and 1992 and responded to a long-term health study. The participants were all free of chronic conditions such as heart disease and cancer at the time of enrollment. Each participant was given a battery of cognitive tests and brain MRI exams. The results showed that participants who were current users of protein supplements had a 35 percent increased risk of developing neurodegenerative disorders such as AD, Parkinson’s disease, and frontotemporal dementia. The risk seemed to be directly related to the amount of protein a participant was taking in: participants who were taking in a total of 4.04 grams of protein per day had a 35 percent risk, while those taking in 5.56 g of protein had a 50 percent risk, and those taking in 9.12 g of protein had a 70 percent risk increase.
Why Are Protein Supplements Linked to an Increase in Neurodegenerative Disorders?
There are two main theories that attempt to explain the findings of this study. The first theory is that the high levels of purine found in some protein powders (especially some fish-based proteins) break down into a compound called 6-N-propyl-2-thiouracil (PrTU) when the powders are digested. PrTU has been shown to be a leading risk factor for developing AD. This theory has been disputed by other scientists who believe that the amount of PrTU in the body is so small that it would have no effect.
The second theory is that the high levels of purine found in some fish-based proteins can trigger the release of Excess amyloid-β (Aβ) into the body. Aβ is a peptide that is involved in the pathogenesis of some neurodegenerative diseases such as AD. This excess Aβ can then aggregate on brain cells (neurons), and interfere with the normal functions of these brain cells. This interference can lead to the symptoms of some neurodegenerative diseases, including mild memory loss, confusion, and difficulty performing routine tasks.
How Do You Prevent Getting a Neurodegenerative Disease?
The best way to prevent a neurodegenerative disease is still unknown. Some research shows that diets rich in antioxidants, such as blueberries, may help prevent the development of AD. Other research shows that maintaining a high level of brain-derived neurotrophic factors in the brain may help prevent the development of AD. Still other research shows that physical exercise has a protective effect against the development of various types of dementia. More research is needed to better understand the relationship between diet and brain health, and to find effective ways to maintain brain health.
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