Alzheimer's disease: The vitamin deficiency found in 70% of patients – signs to spot

Alzheimer’s – the most common cause of dementia – is a devastating condition characterised by the gradual loss of memory and cognitive functions. There are multiple pathologies at play with dementia, but one overarching feature is the loss of synaptic connections in the brain. Some studies have warned that a vitamin deficiency could fuel these mechanisms. One, in particular, is “very common” around the world, according to Healthline.

Dementia cases are set to triple by the midcentury, intensifying calls to improve treatments and preventive measures ahead of the expected surge.

Some foods are regarded as being antidotal for the preservation of cognitive functions. Namely, foods packed with omega-3 and flavonoids.

Other nutrients, such as vitamin D, are often overlooked for their benefits for brain health.

Vitamin D is well known for its role in bone metabolism and protective effects against respiratory illnesses. A deficiency typically causes constipation, weakness and poor appetite, among other symptoms. 

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It is sourced mainly through exposure to the sun, as it is produced in the skin through the action of sunlight.

Due to sunlight being scarce in the UK, it is important to source the nutrient from fatty fish, poultry, and liver, and eggs when possible.

In one study published in the journal Neurology, it transpired that a lack of the so-called “sunshine vitamin” was present in a significant number of cases.

For their study, researchers analysed blood samples of 1,658 people for levels of vitamin D reflected by diet, sun exposure and supplements.


All participants in the study were aged around 65 years and none had dementia at the outset of the investigation.

After the six-year follow-up period, a total of 171 participants had developed dementia and 102 had Alzheimer’s disease.

The findings revealed that invidious with low vitamin D levels had a 53 percent increased risk of developing dementia.

Those with a more serious deficiency had a 125 per cent increased risk of developing dementia compared to participants with normal levels of vitamin D.

He continued: “Clinical trials are […] needed to establish whether eating foods such as oily fish or taking vitamin D supplements can delay or even prevent the onset of Alzheimer’s disease and dementia.

“We need to be cautious at this early stage and our […] results do not demonstrate that low vitamin D levels cause dementia.

“That said, our findings are very encouraging, and even if a small number of people could benefit, this could have enormous public health implications given the devastating and costly nature of dementia.”

Its role in neurological health remains somewhat of a mystery, but some research suggests the nutrient may activate and deactivate enzymes in the brain and the cerebrospinal fluid that are involved in neurotransmitter synthesis and nerve growth.