With an increase in life expectancy, degenerative diseases such as dementia, are of great medical concern. There is now evidence that the B vitamins B12, B6 and folic acid (B9) can help to decrease brain shrinkage and improve cognitive test scores in people with Mild Cognitive Impairment (MCI), a condition that can go on to develop into dementia in 50% of cases.
There are over 800,000 dementia sufferers in the UK, and there are many potential risk factors involved in developing some form of it, be it vascular dementia, Alzheimer’s or another form. The risk factor that Dr Celeste de Jager from Oxford University was looking at was the level of B vitamins in the body and how modifying the amount of these can have physical and cognitive effects. Low levels of B vitamins have been shown to be associated with poor performance on memory tasks, possibly due to a mechanism involving an increase in levels of the amino acid homocysteine. Homocysteine or tHcy is a metabolic break-down product naturally found in the body. But high levels of it can damage the endothelium of blood vessels and possibly impair or even kill brain neurons. Being able to reduce homocysteine levels might help to reduce brain atrophy and shrinkage (which is associated with memory loss as we age).
So Dr de Jager’s team investigated whether increasing the amount of particular B vitamins (which should in turn reduce the amount of homocysteine in the body) would reduce brain shrinkage and also improve scores on the Hopkins Verbal Learning test. They gave 266 elderly people (over 70 years of age) already classified as having MCI a mixture of 0.5mg B12, 20mg B6 and 0.8mg folic acid (these are very high doses), to be taken daily, and monitored them over the course of two years.
Their results were positive. The B vitamins slowed brain shrinkage in the subjects, shown by comparing serial MRI scans of their brains by an average of 30% over two years. Individuals with the highest homocysteine levels seemed to benefit the most from the treatment. They showed 50% less brain shrinkage over the two years and also showed a significantly slower decline in performance on cognitive tests, with those on the treatment being 69% more likely to give a correct answer than those on a placebo.
The next step will be to see if B vitamins can improve symptoms in later stages of brain decline, in those already showing signs of dementia, and on a larger national scale.
But for now, can people make a difference in their own homes? Well, Dr de Jager suggests that reducing alcohol consumption will help, as too much can increase homocysteine levels. And anyone in their 40s and 50s should get their B vitamin levels tested by their GP (there isn’t currently a test for homocysteine available in the UK). If they find they’re deficient, which can be as a result of poor diet, being vegetarian or through poor absorption, they should try to increase their intake. B12 can be found in meat, fish, dairy products and eggs, folic acid is in leafy green vegetables and spinach, and B6 is commonly found in fish and seafood. Legumes and pulses are a good source of all B vitamins. Taking B vitamin supplements in the correct doses may also help, but should be taken with caution, as they can have other effects in the body, such as folic acid causing some cancers to re-occur.
Taking these dietary measures isn’t going to prevent dementia singlehanded, but it will help you eat your way to a healthier brain.