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If you could pop along to your local GP’s office and get a blood test which could reveal if you have a higher risk of dementia or not, would you have it?

The results are in from a prospective study, which found that looking at a woman’s level of homocysteine in their blood might be a useful predictor of your relative risk of developing dementia in subsequent decades.

The good news too is that high levels of homocysteine can be treated using folate, vitamin B6 and vitamin B12.

What isn’t known, is whether treating high homocysteine levels would prevent dementia from developing or defer it. More studies would have to be carried out to show if that is the case or not.

But the evidence is now in that having a high homocysteine level is a risk factor for dementia.

What is homocysteine?

Homocysteine is an amino acid that is very important to the body’s metabolism.
It depends on the presence of folate, Vitamin B6 and Vitamin B 12, which we take in with our diet to be kept to a normal range.

Having too much homocysteine has long been known to be associated as a risk factor for heart disease. It appears that some of the risk factors for cardiovascular disease and Alzheimer’s are the same, such as high blood pressure, high cholesterol, smoking, alcohol and obesity.

Other studies have linked dementia and poor cognition with elevated plasma homocysteine levels.
An 8-year study in the Framingham Study again found a doubling of risk of developing Alzheimer’s in those found to have elevated homocysteine.

What hasn’t been determined is whether it is the high level of homocysteine itself or associated vitamin deficiencies, that causes the damage.

But what is known, is that levels of B12 and folate are commonly found to be deficient in the elderly, as is the increased incidence of neurological disease.

In animal studies, folate and Vitamin B12 and 6 deficiencies were linked to poorer memory and spatial learning, and reduced blood supply to the hippocampus, the specialised area in the brain associated with memory.

What are dietary sources of folate and vitamin B12?

Vitamin B12 is found in a variety of commonly eaten foods including meat, fish, milk, eggs and chicken.
Folate is found in green leafy vegetables such as spinach, peas and grains that have been fortified. Many breads and breakfast cereals now have added folate.

Why is this only about the risk for women and not men?

Well basically it is because the study only included women.
So, simply, the results can’t be extrapolated to men.

This was a prospective study that began in the 1960’s on 1500 women (aged between 38 and 60 yrs) who had blood tests done including recording homocysteine levels and filled in a health questionnaire. Thirty-five years later the data is now in, on discovering which of those women subsequently went on to develop dementia or Alzheimer’s disease.

It was those women who had high homocysteine levels, that had twice the risk of developing Alzheimer’s and their relative risk of developing any form of dementia was 70% greater than normal.

We may now be looking at the possibility of being able to use a simple blood test as part of the risk analysis for determining future dementia or Alzheimer’s risk in middle aged women.

And a simple remedy using folate, vitamin B6 and B12 to reduce the levels of homocysteine.

Dr Jenny Brockis

Dr Jenny Brockis is a medical practitioner and internationally board-certified lifestyle medicine physician, workplace health and wellbeing consultant, podcaster, keynote speaker and best-selling author. Her new book 'Thriving Mind: How to Cultivate a Good Life' (Wiley) is available online and at all good bookstores.

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