Doctor concludes LDL cholesterol may be required to maintain or support memory function

This study was published in the Journal of Alzheimers Disease 2013;34(1):273-9

Study title and authors:
Very old adults with better memory function have higher low-density lipoprotein cholesterol levels and lower triglyceride to high-density lipoprotein cholesterol ratios: KOCOA Project.

Katsumata Y, Todoriki H, Higashiuesato Y, Yasura S, Ohya Y, Willcox DC, Dodge HH.
Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA. katsumat@ohsu.edu

This paper can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/23207484

This study investigated the association between cholesterol levels and memory function. The study included 193 participants, aged 80 and older.

Regarding LDL cholesterol levels, the study found those with better memory function had significantly higher LDL cholesterol levels.

Dr Katsumata concluded: "LDL cholesterol, especially large, buoyant LDL may be required to maintain or support memory function among older people."

Links to other studies:
High cholesterol levels boost memory function
Low cholesterol levels associated with slow mental processing in students
High cholesterol levels are associated with higher intelligence

Low cholesterol levels are associated with poor memory

This study was published in Arteriosclerosis, Thrombosis, and Vascular Biology 2008 Aug;28(8):1556-62

Study title and authors:

Low HDL cholesterol is a risk factor for deficit and decline in memory in midlife: the Whitehall II study.

Singh-Manoux A, Gimeno D, Kivimaki M, Brunner E, Marmot MG.

INSERM U687-IFR69, Hôpital Paul Brousse, Bât 15/16, 16 Avenue Paul Vaillant Couturier, 94807 Villejuif Cedex, France. Archana.Singh-Manoux@inserm.fr

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/18591462

The study investigated the association of cholesterol levels with memory. 3,673 male and female participants, average age 61, were subjected to a short-term verbal memory test.

The study found:
(a) Poor memory was found in 53% more subjects with the lowest levels of high density lipoprotein (HDL) cholesterol, below 40 mg/dL (1.0 mmol/L), compared to those with the highest levels of high density lipoprotein (HDL) cholesterol, above 60 mg/dL (1.5 mmol/L).
(b) Poor memory was found in 10% more subjects with the lowest levels of cholesterol, below 200 mg/dL (5.1 mmol/L), compared to those with the highest levels of cholesterol 240 mg/dL (6.2 mmol/L).

The results of the study indicate that low cholesterol levels are associated with poor memory.

Links to other studies:
High cholesterol levels boost memory function
High cholesterol levels are associated with higher intelligence