Saturday, 27 September 2008

Brain shrinkage

My mum sent me a link to a press release from the Vegetarian and Vegan Foundation. They're a bit annoyed because there's a study from Oxford University that has found a link between lack of vitamin B12 and a loss of brain volume in older people. Some, but for once not very many, newspapers have jumped to the conclusion that being vegetarian causes your brain to shrink. This really isn't what the study says. In fact I've had a look at the abstract (can't seem to get remote access to the paper) and it doesn't look like they looked at diet at all. The Oxford press release, however, does go on about diet with a disclaimer that they haven't done a clinical trial.

I'm not an expert in anything related to health and I don't want this blog be about that so hopefully I'll only make this point once: What use is this sort of press release? I can't do anything with this information. The implication is that I should eat more meat, but there was no clinical trial so this is not justified. It reminds me of the research that said a glass of red wine was good for you based on a chemical that was in it. Trouble is there are other things in it as well and the evidence actually says that this isn't true (BS about this here but I warn there are some 'orrible pictures of tumours for no apparent reason).

EDIT: Here's the Oxford press release so you don't have to click the link...

Vitamin B12, a nutrient found in meat, fish and milk, may protect against brain volume loss in older people, according to a University of Oxford study.

For the study, 107 people between the ages of 61 and 87 underwent brain scans, memory testing and physical exams. The researchers from the Oxford Project to Investigate Memory and Ageing (OPTIMA) also collected blood samples to check vitamin B12 levels. Brain scans and memory tests were also performed again five years later.

The study, published in the journal Neurology, found that people who had higher vitamin B12 levels were six times less likely to experience brain shrinkage compared with those who had lower levels of the vitamin in their blood. None of the people in the study had vitamin B12 deficiency.

Many factors that affect brain health are thought to be out of our control, but this study suggests that simply adjusting our diets to consume more vitamin B12 through eating meat, fish, fortified cereals or milk may be something we can easily adjust to prevent brain shrinkage and so perhaps save our memory,” says Anna Vogiatzoglou of the Department of Physiology, Anatomy and Genetics at Oxford University. “Research shows that vitamin B12 deficiency is a public health problem, especially among the elderly, so more vitamin B12 intake could help reverse this problem. Without carrying out a clinical trial, we acknowledge that it is still not known whether B12 supplementation would actually make a difference in elderly persons at risk for brain shrinkage.”

Previous research on the vitamin has had mixed results and few studies have been done specifically with brain scans in elderly populations. We tested for vitamin B12 levels in a unique, more accurate way by looking at two certain markers for it in the blood,” adds Ms Vogiatzoglou.

Ms Vogiatzoglou says the study did not look at whether taking vitamin B12 supplements would have the same effect on memory.

The study was supported by the UK Alzheimer’s Research Trust, the Medical Research Council, the Charles Wolfson Charitable Trust, the Norwegian Foundation for Health and Rehabilitation through the Norwegian Health Association, Axis-Shield plc and the Johan Throne Holst Foundation for Nutrition Research.

Thesis is inches away from completion, I can smell the freedom already.