Written by: Kevin Cann
More often than not when we are addressing problems related to cholesterol we are referring to its affects on heart health. Cholesterol, for one, is important for maintaining the structure of our cells. It is also the precursor for our steroid hormones, serves as a major role in our inflammatory response, and allows us to convert sunlight into vitamin D. One role of cholesterol that is often overlooked is its affect on our mental health.
Approximately 25% of the cholesterol in our body is made in our brain. The blood-brain barrier even has a protection mechanism to stop this locally produced cholesterol from being exchanged with the lipoproteins in the blood (Bjorkhem, 2004). The cholesterol is actually used to help build the myelin sheath that surrounds the axon of our neurons. Statin drugs and cholesterol lowering diets are widely prescribed to people, is this coming at a cost to our mental health?
Morgan and colleagues attempted to understand the mechanisms that were causing increased suicide attempts and violent deaths in clinical interventions attempting to lower plasma cholesterol. Their study concluded by saying that men aged 70 years and older with low serum cholesterol, were 3 times more likely to develop depressive disorders (Morgan, 1993).
Steegmans and colleagues showed the same results in middle-aged men. Men between 40 and 70 years old with cholesterol below 4.5 mmol/liter had a significantly higher risk of depression than men with cholesterol levels between 6 and 7 mmol/liter (Steegmans, 2000). Women are also at danger of low cholesterol levels causing depression. In another study, 300 women between the ages of 31 and 65 were checked for cholesterol levels and depressive symptoms. The researchers found that women with total cholesterol below 4.7 mmol/liter had significantly higher risk of depression (Horsten, 1997). So how does low serum cholesterol make us depressed?
Cholesterol is an important factor in the receptor sites of the cells binding with the appropriate neurotransmitter, in particular acetylcholine and serotonin. Research has suggested that cholesterol is the facilitator of the attachment between the neurotransmitter and the cell membrane, as well as their delivery to specific protein receptors (Fantini, 2009). Another study goes a step further and hypothesizes that this mechanism actually causes inhibition of neurotransmitter release due to the low levels of cholesterol (Shin, 2009).
Researchers at the University of Penn showed that cholesterol is actually located in the protein portion of the receptor site. They demonstrated that cholesterol actually served to stabilize the protein’s structure. According to Grace Brannigan “Our model takes cholesterol out of the background role in the protein’s structure and function and places it at center stage” (Reese, 2008). Lowering cholesterol can have profound effects on the structure and function of these receptor sites.
Long term use of statins showed significant changes in the structure and function of serotonin cell receptors (Shrivastava, 2010). Serotonin is responsible for fighting off depression and anxiety. Having improper structure and function at these sites will lead to depression in a high number of cases. This is most certainly a topic that should be discussed with your doctor before being placed on a statin drug.
Condemning cholesterol has had a profound effect on our well being. Statin drugs are widely prescribed, and may come at a great emotional cost. Cholesterol causing heart disease has been refuted by solid science throughout the last few decades, and I recommend everyone look at Chris Masterjohn’s site, www.cholesterol-and-health.com, and Chris Kresser’s High Cholesterol Action Plan, http://highcholesterolplan.chriskresser.com/ for more information. There is no need to fear cholesterol as it is important for a number of reasons in our body and may be the missing link to you getting out of a depressed hole.
Horsten, Myriam (1997). Depressive Symptoms, Social Support, and Lipid Profile in Healthy Middle-Aged Women. http://www.psychosomaticmedicine.org/content/59/5/521.long
Steegmans, Paul (2000). Higher prevalence of depressive symptoms in middle-aged men with low serum cholesterol levels. http://www.psychosomaticmedicine.org/content/62/2/205.full.pdf+html
Morgan, R.E. (1993). Plasma cholesterol and depressive symptoms in older men. http://www.sciencedirect.com/science/article/pii/0140673693925569.
Bjorkhem, Ingemar (2004). Brain cholesterol: Long secret life behind a barrier. http://atvb.ahajournals.org/content/24/5/806.short
Shrivastava, Sandeep (2004). Chronic Cholesterol Depletion Using Statin Impairs the Function and Dynamics of Human Serotonin 1A Receptors. http://pubs.acs.org/doi/abs/10.1021/bi100276b.
Reese, Jordan (2008). Penn Biophysicists Create New Model for Protein Cholesterol Interactions in Brain and Muscle Tissue. http://www.upenn.edu/pennnews/news/penn-biophysicists-create-new-model-protein-cholesterol-interactions-brain-and-muscle-tissue.
Fantini, Jacques (2009). Sphingolipid/cholesterol regulation of neurotransmitter receptor conformation and function. http://www.sciencedirect.com/science/article/pii/S0005273609002971
Shin, Yeon-Kyun (2009). Cholesterol, Statins, and Brain Function: A Hypothesis from a Molecular Perspective. http://www.ibc7.org/article/journal_v.php?sid=31.