‘Stroke’ is a term used to describe the manifestation of death in part of the brain. It most common occurs as a result of blocking off in one or more arteries – these are called ‘ischaemic’ stokres. More rarely, strokes can be caused by arteries bleeding into the brain (so-called ‘haemorrhagic’ strokes).
Earlier this week saw the on-line publication of a study which assessed the relationship between magnesium intake and risk of stroke [1]. It found that for each 100 mg increase in magnesium intake, risk of stroke was 8 per cent lower. This association was only found for ischaemic stroke. Taken in isolation, each 100 mg increase in magnesium intake was associated with a 9 per cent reduced risk of ischaemic stroke.
This study is epidemiological in nature, and therefore cannot tell us if magnesium is truly protective for ischaemic stroke (it might be that the association is just that – an association – and that the relationship is not ‘causal’). However, the authors of this paper speculate on a few mechanisms by which magnesium might protect against stroke including:
- an ability to lower blood pressure by a small put potentially important amount
- a relationship between higher magnesium levels and reduced risk of type 2 diabetes (diabetes is a risk factor for stroke)
- an ability for magnesium to bring about favourable changes in blood sugar and blood fat levels
- an ability to reduce oxidation of blood fats (oxidation of blood fats – ‘lipid peroxidation’ – is believed to make them more toxic to the body)
As an aside, I take magnesium everyday (unless I forget). I take it because if I don’t, I get problems with muscular cramp and some spasm in my gullet (oesophageal spasm). I also, as it happens, have quite a strong family history of stroke. This latest evidence gives me another potential reason to keep up a good intake of magnesium.
References:
1. Larsson SC, et al. Dietary magnesium intake and risk of stroke: a meta-analysis of prospective studies. Am J Clin Nutr 28 December 2011 [epub ahead of print]
