Vitamin D deficiency linked to increased dementia and stroke risk


Vitamin D has long been touted as an important part of a person’s health. Not only is it crucial for bone healthTrusted Source, but past research shows vitamin D also plays an important role in immune system functionTrusted Source.

Additionally, vitamin D deficiency has been linked to diabetes, cardiovascular diseaseTrusted Source, and respiratory diseases like acute respiratory distress syndrome (ARDS).
Adding to this list, researchers from the University of South Australia believe they have evidence linking vitamin D deficiency to an increased risk for dementia and stroke.

What is dementia?
The term “dementia” refers to a collection of diseasesTrusted Source that affect a person’s cognitive abilities. Dementia affects people’s ability to think, remember, and communicate normally.
Over 55 million people globally live with dementia. Researchers believe that number will grow to 78 million by 2030.
The most common type of dementia is Alzheimer’s diseaseTrusted Source, accounting for 60% to 70%Trusted Source of dementia cases.

Other types of dementia include:
• Vascular dementia
• Lewy body dementia
• Frontotemporal dementiaTrusted Source
• Parkinson’s disease dementia
• Huntington’s diseaseTrusted Source
In addition to vascular dementia caused by stroke, past researchTrusted Source shows stroke patients have an increased risk of developing dementia.
Shedding light on vitamin D
Researchers analyzed genetic data from almost 295,000 participants in the UK Biobank biomedical database for this study. Scientists measured variations in participants’ genes to find how a low vitamin D level impacted a person’s neuroimaging of the brain and their risk for dementia and stroke.

Researchers associated a lower vitamin D level with a lower brain volumeTrusted Source and an increased risk of dementia and stroke. They also stated their genetic analysis supports vitamin D deficiency’s causal effect on dementia.

According to Prof. Elina Hyppönen, senior investigator and director of the Australian Centre for Precision Health at the University of South Australia, researchers have long suspected that vitamin D may have implications for the development of neurocognitive diseases such as dementia. However, evidence about whether these effects are causal has been lacking.

“Indeed, it has been very difficult to prove the effects of vitamin D on brain health or other diseases, in large part as clinical trials in people who are clinically vitamin D deficient would not be ethical to conduct,” Prof. Hyppönen told Medical News Today.
“Therefore, using a novel genetic design, we wanted to see whether we can provide causal evidence for a role of vitamin D in brain health, and specifically, to see whether improvements in vitamin D status among people who are vitamin D deficient will help,” she explained.

Previous research — including a study in 2018 that conducted a systematic review and analysis of over 70 clinical and pre-clinical studies about the role of vitamin D in neurodegenerative diseases like Alzheimer’s and Parkinson’s disease — concluded there was no concrete evidence that vitamin D was neuroprotective.
Vitamin D and cholesterol: What to know
• Vitamin D and cholesterol
• About vitamin D
• Vitamin D deficiency
• High cholesterol levels
• Seeking medical advice
• Summary

The connection, if any, between vitamin D and cholesterol is unclear. Some research suggests that vitamin D supplements may improve cholesterol levels. However, others indicate that vitamin D has no effect on low-density lipoprotein (LDL) cholesterol.

Vitamin D is important for maintaining healthy bones and teeth, and the human body produces it when the skin has exposure to the sun. However, a person may also take vitamin D supplements.

The body also produces cholesterol. As this substance is in some foods, people may take in extra through their diet. Cholesterol plays several roles in the body, contributing to the production of vitamin D and several hormones.

Keep reading to learn about vitamin D, including its possible connection to cholesterol, its benefits, and the effects of a vitamin D deficiency.