Category: Nutrition

Over 1 billion people worldwide have a vitamin D deficiency.

Difficulties with memory and learning are signs of vitamin D deficiency, research finds.

Vitamin D deficiency is even linked to disorders such as depression and schizophrenia.

Deficiency in the vitamin affects critical structures in the hippocampus, an area of the brain important in memory and learning.

Dr Thomas Burne, study co-author, said:

“Over a billion people worldwide are affected by vitamin D deficiency, and there is a well-established link between vitamin D deficiency and impaired cognition.

Unfortunately, exactly how vitamin D influences brain structure and function is not well understood, so it has remained unclear why deficiency causes problems.”

For the study, researchers removed vitamin D from the diets of mice for 20 weeks.

The mice clearly showed problems with learning and memory compared to a control group, who were fed sufficient levels of vitamin D.

The researchers found that vitamin D is important in keeping perineuronal nets in the hippocampus stable.

Dr Burne explained:

“These nets form a strong, supportive mesh around certain neurons, and in doing so they stabilise the contacts these cells make with other neurons.

As neurons in the hippocampus lose their supportive perineuronal nets, they have trouble maintaining connections, and this ultimately leads to a loss of cognitive function.”

The hippocampus is a particularly active part of the brain, which may be why it is affected by vitamin D deficiency early on, said Dr Burne:

“It’s like the canary in the coalmine—it might fail first because its high energy requirement makes it more sensitive to the depletion of essential nutrients like vitamin D.

Intriguingly, the right side of the hippocampus was more affected by vitamin D deficiency than the left side.”

The damage to these perineuronal nets may help to explain the memory problems that are a symptom of schizophrenia.

Dr Burne said:

“The next step is to test this new hypothesis on the link between vitamin D deficiency, perineuronal nets and cognition.

We are also particularly excited to have discovered these nets can change in adult mice.

I’m hoping that because they’re dynamic there is a chance that we can rebuild them, and that could set the stage for new treatments.”

The study was published in the journal Brain Structure and Function (Al-Amin et al., 2019).

Around half the world’s population are thought to have an insufficiency of this vitamin.

A triple dose of vitamin D3 supplementation in the first two years of life reduces the chance of mental health problems later on by around 50 percent, a high-quality experiment finds.

Infants who were given 30 µg of vitamin D daily, which is three times the recommended dose, were only half as likely to have internalising problems by age 6-8.

Internalising problems are those in which a person keeps their problems to themselves, including depression, anxiety, loneliness and withdrawal.

Dr Samuel Sandboge, the study’s first author, said:

“Our results suggest that a higher dose of vitamin D3 supplementation during the first years of life may reduce the risk of internalizing psychiatric symptoms in late preschool and early school age.”

Vitamin D and mental health

The randomised controlled trial, which was carried out in Finland, was inspired by the link found between low childhood vitamin D levels and mental health problems.

Almost 350 children were given either a dose of 10 µg or 30 µg of vitamin D from age 2 weeks until 2-years-old.

The results showed that at 6- to 8-years-old, almost 12 percent of children given 10 µg had significant internalising problems.

In the 30 µg group, though, this figure was under 6 percent.

No differences were seen in the number of externalising problems.

Externalising disorders include ADHD and conduct disorder.

Later in life externalising disorders include substance abuse, antisocial personality disorders and even psychopathy.

Dr Samuel Sandboge warned that the study has drawbacks:

“The results and their potential implications are interesting, but further research is needed to confirm the results.

In the interpretation of the results, we must note, among other things, that we studied the psychiatric symptoms only as parent-reported.

Furthermore, the participants of the study were children with Nordic ancestry living in Finland who had good levels of vitamin D.”

Widespread deficiency

Around half the world’s population are thought to have an insufficiency of vitamin D, and 10 percent are deficient.

Vitamin D plays an important role in the development of the brain.

It is notable that a rise in autism and ADHD rates has happened at a time when there have been significant drops in average levels of vitamin D.

Related

• A mother’s deficiency in vitamin D may contribute to the development of autism in her children.
• Zinc deficiency could be involved in the development of autism.
• Vitamin D activates a gene which produces an enzyme leading to higher levels of serotonin.

The study was published in JAMA Network Open (Sandboge et al., 2023).

B12 deficiency is relatively easy to correct with a change in diet or supplementation.

Difficulties with memory and thinking skills can be a sign of vitamin B12 deficiency, research finds.

Low levels of the vital vitamin are linked to accelerated cognitive aging.

With age, people’s brains generally work more slowly, their reasoning is not as sharp and their memory less clear.

However, people with normal vitamin B12 levels age better cognitively.

Vitamin B12 deficiency has been linked to Alzheimer’s disease and brain shrinkage by some research.

The good news is that B12 deficiency is relatively easy to correct with a change in diet or supplementation.

Good sources of vitamin B12 include fish, poultry, eggs and low-fat milk.

Fortified breakfast cereals also contain vitamin B12.

For the study, 549 people, average age 75, were split into groups based on their vitamin B12 levels.

The results showed that being in the two lowest groups for vitamin B12 was linked to a more rapid cognitive decline over eight years.

Dr Martha Savaria Morris, the study’s first author, said:

“Men and women in the second lowest group did not fare any better in terms of cognitive decline than those with the worst vitamin B12 blood levels.

Rapid neuropsychiatric decline is a well-known consequence of severe vitamin B12 deficiency, but our findings suggest that adverse cognitive effects of low vitamin B-12 status may affect a much larger proportion of seniors than previously thought.”

People who may have difficulty getting enough vitamin B12 include vegetarians, older people and those with some digestive disorders, such as Crohn’s disease.

Dr Paul Jacques, study co-author, said:

“While we emphasize our study does not show causation, our associations raise the concern that some cognitive decline may be the result of inadequate vitamin B-12 in older adults, for whom maintaining normal blood levels can be a challenge.”

The study was published in the Journal of the American Geriatrics Society (Morris et al., 2012).

Good sources of vitamin B12 include fish, poultry, eggs and low-fat milk.

Memory problems can be a sign of vitamin B12 deficiency, research finds.

People with B12 deficiency can experience worse memory for both ideas and events.

The vitamin deficiency has also been linked to Alzheimer’s disease and brain shrinkage by some research.

The good news is that B12 deficiency is relatively easy to correct with a change in diet or supplementation.

Good sources of vitamin B12 include fish, poultry, eggs and low-fat milk.

Fortified breakfast cereals also contain vitamin B12.

People who may have difficulty getting enough vitamin B12 include vegetarians, older people and those with some digestive disorders, such as Crohn’s disease.

The conclusions about the link between Alzheimer’s and B12 come from a study of 271 Finnish people aged 65-79 who were followed for 7 years.

At the start of the study, all were healthy — however, by the end, 17 had developed Alzheimer’s.

Blood tests showed that higher levels of vitamin B12 were associated with a lower risk of developing the disease.

Dr Babak Hooshmand, the study’s first author, said:

“Our findings show the need for further research on the role of vitamin B12 as a marker for identifying people who are at increased risk of Alzheimer’s disease.

Low levels of vitamin B12 are surprisingly common in the elderly.

However, the few studies that have investigated the usefulness of vitamin B12 supplements to reduce the risk of memory loss have had mixed results.”

Dr Hooshmand cautioned that B12 supplements for memory problems are not yet supported unequivocally by the research:

“More research is needed to confirm these findings before vitamin B12 should be used solely as a supplement to help protect memory.”

The study was published in the journal Neurology (Hooshmand et al., 2010).

Up to 70 percent of people could have a vitamin D deficiency.

Symptoms of depression can be a sign of vitamin D deficiency, research suggests.

Depression symptoms include moodiness, lack of motivation and tiredness, as well as physical signs like headaches, stomach aches and dizziness.

As many as 70 percent of people could have a vitamin D deficiency.

Foods that are rich in vitamin D include oily fish and eggs, but most people get their vitamin D from the action of sunlight on the skin.

That is why levels are typically lower in the body through the winter months in more Northern climes.

Studies have also linked vitamin D deficiency to dementia.

One study including 286 people with Parkinson’s disease (PD) found higher levels of vitamin D were linked to better cognitive functioning.

Dr Amie L. Peterson, the study’s first author, said:

“About 30% of persons with PD suffer from cognitive impairment and dementia, and dementia is associated with nursing home placement and shortened life expectancy.

We know mild cognitive impairment may predict the future development of dementia.

Intervening in the development of dementia has the potential to improve morbidity and mortality in persons with PD.”

People in the study were given tests of their cognitive function, any depression symptoms and vitamin D levels.

The results showed that people with higher vitamin D levels had better cognitive function and fewer symptoms of depression.

They could name more vegetables and animals in one test and displayed better memory in another test.

Dr Peterson said:

“The fact that the relationship between vitamin D concentration and cognitive performance seemed more robust in the non-demented subset suggests that earlier intervention before dementia is present may be more effective.”

Low levels of vitamin D has been connected to a number of diseases including multiple sclerosis, type 2 diabetes, hypertension and cancer.

Vitamin has also been implicated in human memory.

The study was published in the  Journal of Parkinson’s Disease (Peterson et al., 2014).