It is well-known that high blood cholesterol levels are not good for the heart. Is is also quite known that high levels of low-density lipoproteins (LDL) – the bad type of cholesterol – can build up and block arteries and adversely affect cardiovascular health.
What is not so well-known is the fact that low levels of high-density lipoproteins (HDL) – the good type of cholesterol – is linked to memory loss and increased risk for dementia. This is according to a study by European researchers.
It seems that cholesterol levels are important not only for heart health but for brain health as well.
The study followed up 3,673 people as part of the long-term Whitehall II study involving British civil servants. The results showed that low levels of HDL cholesterol are associated with diminished memory by age 60. No link was found between memory loss and levels of total cholesterol and triglycerides. The use of statins to manage cholesterol levels did not seem to have an effect.
According to lead author Dr. Archana Singh-Manoux of the French National Institute for Health and Medical Research (INSERM, France) and the University College London (UK)
“Memory problems are key in the diagnosis of dementia. We found that a low level of HDL may be a risk factor for memory loss in late midlife. This suggests that low HDL cholesterol might also be a risk factor for dementia.”
The mechanism behind this link between HDL cholesterol and dementia risk is not so clear but the following hypotheses are proposed:
- HDL cholesterol blocks the formation of beta-amyloid.
- HDL cholesterol may affect memory in relation to its role in maintaining vascular health.
- HDL cholesterol could influence memory through its -inflammatory and antioxidant.
HDL cholesterol… serves several vital biological functions. It helps clear excess cholesterol from the blood; assists nerve-cell synapses to mature; and helps control the formation of beta-amyloid, the major component of the protein plaques found in the brains of Alzheimer’s patients.
Dementia usually occurs in people 65 years or older. Alzheimer’s disease is the most common form of dementia. In the developed world where a large proportion of the population are elderly, dementia is becoming a major – and costly – health concern. The monitoring of HDL cholesterol (and not only LDL cholesterol!) should therefore be encouraged – for the heart as well as for the brain.
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