Category: Dementia

The study looked directly at levels of this vitamin in the brain, about which little is known.

Higher levels of vitamin D in the brain are linked to better cognitive function and less decline with age.

Indeed, adequate vitamin D levels have repeatedly been linked to lower dementia risk (1, 2, 3) by research.

One study has even suggested that adequate levels of vitamin D could prevent almost one-in-five cases of dementia (Navale et al., 2022).

However, the link remains somewhat controversial, with other studies finding no connection (also: Owusu et al., 2018).

This research, though, looked directly at vitamin D levels in the brain, about which little is known.

Professor Sarah Booth, study co-author, said:

“This research reinforces the importance of studying how food and nutrients create resilience to protect the aging brain against diseases such as Alzheimer’s disease and other related dementias.”

Vitamin D markers

The study, which tracked the cognitive health of 290 seniors, analysed their brain tissue for vitamin D after they died.

Dr Kyla Shea, the study’s first author, said:

“Many studies have implicated dietary or nutritional factors in cognitive performance or function in older adults, including many studies of vitamin D, but all of them are based on either dietary intakes or blood measures of vitamin D.

We wanted to know if vitamin D is even present in the brain, and if it is, how those concentrations are linked to cognitive decline.”

The researchers found that people with higher levels of vitamin D in their brains had better cognitive function.

However, they found no link between vitamin D markers and other physiological signs of Alzheimer’s.

This means it is difficult to pinpoint the mechanism by which vitamin D might be beneficial.

Dr Shea said:

“Dementia is multifactorial, and lots of the pathological mechanisms underlying it have not been well characterized.

Vitamin D could be related to outcomes that we didn’t look at yet, but plan to study in the future.”

How much vitamin D?

Despite these findings, it is not recommended to take high levels of vitamin D as a preventative measure.

Recommended doses are 600 IU per day for people under 70 and 800 IU for those over 70.

Dr Shea said:

“We now know that vitamin D is present in reasonable amounts in human brains, and it seems to be correlated with less decline in cognitive function.

But we need to do more research to identify the neuropathology that vitamin D is linked to in the brain before we start designing future interventions.”

The study was published in the journal Alzheimer’s & Dementia (Shea et al., 2022).

You don’t need diabetes for this everyday factor to cause brain damage.

The average person eats the equivalent of an extra burger meal every day compared with 50 years ago.

A burger, fries and soft drink works out to an extra 650 calories per day.

That is around 30 percent more calories than people need.

The consequences for people’s waistlines and their brains is devastating.

Brain health declines dramatically as a result of poor nutrition, especially early in life.

One of the main culprits is sugar, which accelerates neurodegeneration and impairs cognitive function.

Even ‘high-normal’ levels of blood sugar contribute to neurodegenerative processes.

People need to eat well and exercise early in life to avoid brain shrinkage and dementia later on.

Professor Nicolas Cherbuin, the study’s first author, said:

“People are eating away at their brain with a really bad fast-food diet and little-to-no exercise.

We’ve found strong evidence that people’s unhealthy eating habits and lack of exercise for sustained periods of time puts them at serious risk of developing type 2 diabetes and significant declines in brain function, such as dementia and brain shrinkage.”

The conclusions come from a review of around 200 studies carried out around the world.

Fully 30 percent of the world’s population is obese now, and 10 percent will have type 2 diabetes by 2030.

Professor Cherbuin said:

“The link between type 2 diabetes and the rapid deterioration of brain function is already well established.

But our work shows that neurodegeneration, or the loss and function of neurons, sets in much, much earlier—we’ve found a clear association between this brain deterioration and unhealthy lifestyle choices.

The damage done is pretty much irreversible once a person reaches midlife, so we urge everyone to eat healthy and get in shape as early as possible—preferably in childhood but certainly by early adulthood.”

The effort to improve diet is coming too late for many, said Professor Cherbuin:

“What has become really apparent in our investigation is that advice for people to reduce their risk of brain problems, including their risk of getting dementia, is most commonly given in their 60s or later, when the ‘timely prevention’ horse has already bolted.

Many people who have dementia and other signs of cognitive dysfunction, including shrinking brains, have increased their risk throughout life by eating too much bad food and not exercising enough.

One of the best chances people have of avoiding preventable brain problems down the track is to eat well and exercise from a young age.

The message is simple, but bringing about positive change will be a big challenge.

Individuals, parents, medical professionals and governments all have an important role to play.”

The study was published in the journal Frontiers in Neuroendocrinology (Cherbuin & Walsh, 2019).

90% use too much of an everyday substance that can cause inflammation of blood vessels in the brain, which is linked to dementia.

A high-salt diet is linked to cognitive decline and possibly dementia.

Salt causes the delicate lining of the brain’s blood vessels to inflame, because of signals sent from the gut.

Fully 90 percent of Americans consume above the recommended dietary maximum of 2,300 mg per day.

Dr Costantino Iadecola, study co-author, said:

“We discovered that mice fed a high-salt diet developed dementia even when blood pressure did not rise.

This was surprising since, in humans, the deleterious effects of salt on cognition were attributed to hypertension.”

The effect was quickly reversed by lowering salt intake.

The conclusions come from a study in which mice were fed a high-salt diet that is equivalent to a high-salt diet in humans.

Subsequently, the mice had much worse cognitive function.

Their brains showed 28 percent less activity in the cortex and 25 percent less in the hippocampus.

They had problems getting around a maze and did not show the usual interest in new objects placed in their cage.

They also had poorer blood flow in their brains and the integrity of the blood vessels there was worse.

However, these changes were reversed once the mice were returned to a normal diet.

The scientists found that these changes had nothing to do with higher blood pressure.

Worse cognitive functioning in the mice was seen even when the mice had normal blood pressure.

They were the result of signals sent from the gut to the brain.

These activated an immune response in the brain which increased levels of interleukin-17.

This eventually resulted in the inflammation of the delicate lining of the brain’s blood vessels.

Related

• 10 Science-Backed Ways To Slash Your Dementia Risk Today (P)

The study was published in the journal Nature Neuroscience (Faraco et al., 2018).

Even a year after taking part in the study, the way some older people’s brains processed language was more akin to young people.

Only tasks which involve sustained mental effort can help protect the brain from aging.

Activities like digital photography or quilting can provide the necessary mental stimulation.

Socialising, listening to music or playing simple games, though, did not have the same beneficial effects, researchers found.

Dr Denise C. Park, one of the study’s authors, said:

“The present findings provide some of the first experimental evidence that mentally-challenging leisure activities can actually change brain function and that it is possible that such interventions can restore levels of brain activity to a more youth-like state.

However, we would like to conduct much larger studies to determine the universality of this effect and understand who will benefit the most from such an intervention.”

The study involved assigning older adults to both high-challenge and low-challenge activities.

They continued these for around 15 hours a week over 14 weeks.

Only the activities that provided an active learning component were beneficial.

People who learned quilting or digital photography showed impressive improvements:

• Better memory performance.
• Higher abliity to regulate brain activity.
• Better neural efficiency.

Some of these gains were maintained up to one year later.

The way these older people’s brains processed language was more akin to young people than their counterparts in the low-challenge group.

Dr Ian McDonough, who co-authored the study, said:

“The study clearly illustrates that the enhanced neural efficiency was a direct consequence of participation in a demanding learning environment.

The findings superficially confirm the familiar adage regarding cognitive aging of ‘Use it or lose it.'”

Dr Park added:

“Although there is much more to be learned, we are cautiously optimistic that age-related cognitive declines can be slowed or even partially restored if individuals are exposed to sustained, mentally challenging experiences.”

Related

• 10 Science-Backed Ways To Slash Your Dementia Risk Today (P)
• 12 Brain-Boosting Strategies That Protect Against Mild Cognitive Impairment (P)

The study was published in the journal Restorative Neurology and Neuroscience (McDonough et al., 2015).