How B vitamins could slow down cognitive decline and protect against dementia

TUFTS researchers report that eight key nutrients can influence dementia, cardiovascular diseaseand other health problems.

Eight vital nutrients form the group of vitamins B called Complex B. Research at TUFTS University and beyond has shown that these vitamins play a role in many areas of health, influencing brain function, heart health, recovery after gastric bridging, prevention of neural tube defects and even the risk of cancer.

“It is difficult to study the vitamins B in isolation,” explains gastroenterologist Joel Mason, principal scientist of Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) and professor at Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy and Tufts University School of Medicine. “Four of these B vitamins cooperate as a co-factor in many critical activities in cells in what we call” a carbon metabolism “.”

A carbon metabolism refers to interconnected pathways which allow cells to transfer single carbon units for vital functions such as DNA Synthesis and amino acid treatment. Because vitamins B are at the heart of these processes, they are both essential for human health and difficult to assess individually, because their effects overlap.

Mason, as well as two other longtime vitamin B researchers, describes what is currently included on how five of the most studied vitamins B the most studied the most studied influence both cognitive performance and cardiovascular health.

Cognitive health, B12 and Folate

Cognitive health remains one of the most studied areas of research in vitamins B. According to Mason, when individuals reach 75 to 80 years, about 40% have a reduced capacity to absorb vitamin B12 linked to food. This shortage contributes to the deterioration of nervous health, especially in the brain and spinal cord, increasing the risk of dementia in the elderly.

For many years, clinicians assumed that plasma B12 measures were sufficient to determine if supplementation was necessary. Mason notes, however, that many elderly people whose levels of B12 are in the “low to normal” range still develop neurological deficiencies caused by a vitamin B12 deficiency.

“The contribution of vitamin B12 deficiency to cognitive decline and vascular disease that results in many cases of dementia is underdiagnosed and underestimated”, explains Irwin H. Rosenberg, professor of the University of Jean Mayer, emeritus in Tufts and former dean of the School of Medicine Friedman.

“The age -related cognitive decline is not only Alzheimer’s“Adds Rosenberg.” We have gathered many types of cerebral dysfunction under one name. And in doing so, we have neglected how critical blood vessels – and by extension, nutrition – are to preserve the brain function. »»

Alzheimer’s disease is traditionally associated with the accumulation of two proteins in the brain, the amyloid and the tau, which bend in plates and tangles that interfere with neural function.

Rosenberg, however, stresses that cerebrovascular diseases and small vessels’ diseases – whose dementia can be influenced by vitamin B deficiencies – are more often linked to dementia and cognitive decline than the accumulation of these proteins. He emphasizes that drug treatments targeting protein accumulation will not be effective if B12 deficiency is the underlying cause.

It is essential to test the deficiency in B12 when evaluating the symptoms of dementia, argues Rosenberg.

“The B12 tests measure all the B12 of your system, even if about 80% are inactive,” explains Paul Jacques, principal scientist of HNRCA and professor at the Friedman School of Nutrition Science and Policy.

To properly diagnose a deficiency, two additional tests are necessary. The first, the MMA test, measures methylmalonic acid, a metabolic by-product that increases when B12 levels are insufficient. “It can be high with even a slight B12 deficiency, indicating a potential risk of higher dementia,” explains Jacques.

The second test measures homocysteine, another compound produced during metabolism which also requires B12. If only homocysteine ​​is high, a folate deficiency can be the cause, but if MMA and homocysteine ​​are high, a B12 deficiency is the most likely explanation.

Reversible causes of cognitive decline

If a patient has neurological problems or signs of dementia, the realization of the three tests will shrink if a vitamin B deficiency is involved – and which vitamin B is.

“Contrary to the changes that we are unable to see in patients who benefit from expensive anti-amyloid antibodies to treat Alzheimer’s disease, there are actually proven that early enough during cognitive decline, we can slow down the process if the underlying cause is high homocysteine ​​or a deficiency linked to B12”, explains Rosenberg. “It is my recommendation that patients, with or without anemia, should be detected for homocysteine ​​or high B12 deficiency, as this can be one of the reversible factors of their cognitive decline.”

This is not a new theory. Two decades ago, studies like Framingham Heart Study showed that high homocysteine ​​predicts brain atrophy and a higher risk of dementia. More recently, trials such as Vitacog and Fact have shown that vitamin B supplementation can slow brain narrowing and improve cognitive performance in people at risk.

“There is a huge amount of education necessary around this problem,” explains Rosenberg. “We hope to convince cardiologists, neurologists and internists to measure the levels of B12 and homocysteine ​​in the context of the evaluation of cognitive impairment. Even the modest effects of vitamins that cost the cents per day can be very significant in those who benefit from it, especially when you compare vitamins supplementation to expensive drugs that attract much more attention, however the same or even enjoy. “

“There is evidence that quite early in the cognitive decline, we can slow down the process if the underlying cause is a deficiency linked to B12,” said Irwin H. Rosenberg, professor emeritus of Jean Mayer University and former dean of the Friedman School of Nutrition Science and Policy University

B12 and dementia

Jacques and his colleagues are currently directing a study using data of around 2,500 adults of middle ages and older in the study by Framingham Heart, who were all free from dementia in the 1990s and all received B12, MMA and homocysteine ​​tests in the past 20 years.

“The risk of dementia and Alzheimer at a late stage begins to increase when you are 75 years old or over, but the evidence suggests that some of the pathological changes associated with dementia and Alzheimer can start developing more than 20 years before clinical symptoms and diagnosis,” explains Jacques. “This study should give us a good idea of ​​the question of whether B12 is linked to cognitive decline and dementia. If this is the case, we hope that we can identify a simple and inexpensive intervention which could be launched years in advance and before real damage occurs. ”

Jacques also examines the role that Folat (B9) can play in the development of cognitive problems, in particular the influence of high folate levels could have on B12 and cognitive health.

In the 1950s, people with anemia were treated with folic acid, the synthetic form of the Folate. Unfortunately, it has become clear that, although the pharmaceutical treatment with folic acid has attenuated anemia, it has often masked or exacerbated the deficiency in B12. “Scientists observed that people with low B12 and high concentrations of folic acid tend to have cognitive problems,” explains Jacques.

More recent research has suggested that it was not total B12 concentrations that folic acid could affect, but perhaps a single component, Holotc, which is the form of vitamin B12 which is crucial for the transport and use of B12 in cells and is considered a potentially better indicator of vitamin B12.

Jacques and his colleagues carry out two studies to tease the problems concerned. “In the first, our study B vitamin and Brain, we will examine the influence on the status of high folate on the relations between B12 and cognitive health. A second study that we do in collaboration with Rutgers will examine the effect of folic acid raised in the blood on the two forms of B12 – Hololotc and unrelated Cobalamine. “

Heart disease, cholesterol and stroke

Vitamins B have also aroused the excitation of researchers because of their possible role in the prevention of heart disease and cerebral vascular accidents, but so far, their usefulness as a clinical treatment remains limited.

Scientists discovered in the early 2000s that Riboflavin (B2) could very effectively decrease blood pressure. It is believed that riboflavin improves a biochemical reaction mediated by a gene called MTHFR (methylènetrahydrofolate reductase) which helps the body to use the folate. Riboflavin is only effective in reducing blood pressure specifically in patients with the MTHFR 677 TT genotype.

Vitamins B6, B12 and Folate help the body get rid of homocysteine, which, in the overabundance, had been linked to an increased risk of heart attacks and strokes, as well as dementia. However, a number of clinical trials in the 1980s showed that B6, B12 and folate supplementation did not decrease heart attacks, but slightly reduced the risk of lines.

Niacin (B3) can reduce LDL (the so-called “bad cholesterol”) and increase HDL (the so-called “good cholesterol”). “But it is necessary to take in such important doses that it often causes a very uncomfortable rinsing, like hot flashes,” explains Mason. “People can often not tolerate it, and other drug options are available that reduce LDL Bloods which have no unpleasant side effects.”

Chronic inflammation and B6

Perhaps the most promising for the future is the role that vitamin B6 can play in the fight against inflammation, which has been identified as an underlying characteristic of many chronic diseases, from heart disease to diabetes via dementia arthritis.

A certain number of animal studies, as well as certain human studies, suggest that the additional B6 can reduce inflammation. “Once again, we are talking about giving B vitamins to an appropriate pharmaceutical level in the care of a clinician,” warns Mason. “B6 can be toxic in large quantities.” He considers this research as an area to look at in the years to come.

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