Cholesterol and our Mental Health
For the last quarter century, we have been told that cholesterol is dangerous for our health and were advised to avoid it in order to live a healthier life. However, cholesterol is essential in maintaining good mental health. The brain is the most cholesterol-rich organ in the body, and depriving the brain of essential fatty acids and cholesterol can lead to detrimental health problems. Lower levels of cholesterol in the blood are associated with a heightened risk of developing major depressive disorder, as well as an increased risk of death from suicide. (3)
Most people think of heart disease when they hear the words "high cholesterol," but your brain's health may also be at stake. The evidence is still limited, but studies show that high levels of cholesterol may be linked to Alzheimer's disease or other kinds of dementia. (4)
Cholesterol, for one, is important for maintaining the structure of our cells. One role of cholesterol that is often overlooked is its effect on our mental health and this is what we will investigate further in this paper.
First and foremost, let’s look at the brain and what it consists off and its chemistry. It fascinating to see how its all connected and the need for cholesterol is so important.
Approximately 25% of the cholesterol in our body is made in our brain. The blood-brain barrier has protection mechanism to stop locally produced cholesterol from being exchanged with the lipoproteins in the blood. The cholesterol is actually used to help build the myelin sheath that surrounds the axon of our neurons. Cholesterol is an important factor in the receptor sites of the cells binding with the appropriate neurotransmitter, in particular acetylcholine and serotonin. Having improper structure and function at these sites will lead to depression in a high number of cases. Serotonin is responsible for fighting off depression and anxiety. (5)
Cholesterol is a critical precursor to many essential physiological molecules in the human body that directly and indirectly affect our moods and optimal brain function. Some researchers theorize that low levels of cholesterol alter brain chemistry, suppressing the production and/or availability of the neurotransmitter serotonin. (3) Moreover, 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. Another study goes a step further and hypothesizes that this mechanism actually causes inhibition of neurotransmitter release due to the low levels of cholesterol. (5)
Cholesterol is one of the suggested essential nutritional components that may be beneficial for mental health. As life span of human being is increasing, the more the prevalence of mental disorders is, the more attention rises. Cholesterol also constitutes neuronal membrane to be responsible for fluidity, and acts as a signaling modulator for gene transcription, which is involved in nutrients metabolism and inflammation. (2)
Many studies have been done to test the effects of cholesterol on depression and mental health.
A study on middle-aged showed the same results that 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. (5)
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. (5)
In a large Korean Cancer Prevention Study cohort (n = 1,329,525), risk of depression was related to low levels of serum cholesterol concentration, suggesting the possible needs of cholesterol-raising regimen in subjects with depression. However, a dietary intervention in increasing blood cholesterol has not been tried because the cholesterol-raising regimen such as high intakes of saturated fat, trans-fat, cholesterol, and total calories can cause increased the risk of other metabolic diseases (e.g. obesity, diabetes, and CVD). Evidence on the effect of cholesterol is conflicting; however, in general, blood cholesterol levels are negatively associated with the risk of depression. (2)
Several studies have linked low cholesterol levels to an increased risk of developing depression including a 2008 meta-analysis, which found that higher total cholesterol was associated with lower levels of depression. A 2010 study published in The Journal of Neuropsychiatry & Clinical Neurosciences looked at the levels of HDL in depressed people and found that low levels of HDL were linked to "long-term depressive symptomatology. The connection between low cholesterol and suicide is highlighted in a 2004 study, which concluded that a low total cholesterol level can be used as an indicator of suicide risk. This study, involving suicide attempters with major depressive disorder, nonsuicidal depressed patients, and normal controls, found significant differences in cholesterol levels among the various groups. (3)
In a recent study, looking at levels of amyloid in the brains of 74 older adults. They found that higher levels of LDL cholesterol and lower levels of HDL cholesterol both were linked to having more amyloid in the brain known to contribute to Alzheimer's, in the same way that such patterns promote heart disease. (4)
There is a growing amount of research looking at the use of essential fatty acids, particularly omega-3's in psychiatry, but we often overlook cholesterol. Low levels of cholesterol and essential fatty acids are intimately linked to depression. Understanding the consequences of deficiencies in essential fats and cholesterol is important for the effective treatment of depression. Whether it is drug induced, genetic, or a result of dietary patterns, low cholesterol impairs optimal brain function and often prevents successful recovery from chronic depression. For individuals with low cholesterol, a diet with adequate cholesterol and healthy saturated fats is highly recommended in order to replenish cholesterol levels, although supplemental cholesterol may also be needed for many. (3)
In conclusion, changes in our lifestyle can improve our cholesterol numbers and contribute to our mental health preventing us from diseases like depression and dementia. A diet low in saturated fat may help reduce LDL "bad" cholesterol. Regular exercise may be helpful in boosting HDL "good" cholesterol (4).
References:
The puzzling relationship between cholesterol and psychopathology (2018) https://www.mdedge.com/psychiatry/article/155154/somatic-disorders/puzzling-relationship-between-cholesterol-and
Nutritional Factors Affecting Mental Health (2016) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4967717/
The Implications Of Low Cholesterol In Depression And Suicide (2015) https://www.greatplainslaboratory.com/articles-1/2015/11/13/the-implications-of-low-cholesterol-in-depression-and-suicide
Can Low Cholesterol Keep Your Brain Healthy?(2014) https://www.webmd.com/cholesterol-management/features/can-low-cholesterol-keep-your-brain-healthy
Cholesterol and Mental Health (2012) https://robbwolf.com/2012/11/01/cholesterol-mental-health/
The Nutrition Academy, Functional Nutrition Course, Cholesterol & Fats https://thenutrition.academy/functional-nutrition-course/