Genetic Associations with Bulimia Nervosa
Contributor: Carrie A. Decker, ND, Naturopathic physician
As the techniques available for assessing the genetic code one is born with become more readily available, research in the field of genetics associated with diseases also continues to grow.
With an understanding of the genetic variants or where an individual may be functioning sub-optimally, therapeutic drugs and supplements can be better directed at the cause of the problems rather than selected from a one-size-fits-all list of pharmaceutical interventions.
The Prevalence of Anxiety Disorders in Those with Eating Disorders
The prevalence of anxiety disorders in general, particularly obsessive compulsive disorder has been found to be much higher in people with anorexia nervosa and bulimia nervosa1. Anxiety disorders have been found to have their onset in childhood before the onset of an eating disorder.
For many who have struggled with an eating disorder in the past or currently, this may not be a surprise. Oftentimes individuals in recovery from an eating disorder find some relief from their anxiety and symptoms by the use of medications or supplements that help moderate anxiety and depression.
The Relationships Between Genetic Variants and Mental Health Issues
More interestingly, and therapeutically useful, is the relationships which are being shown between specific genetic variants with conditions such as bulimia nervosa, anxiety, and depression. A genetic variant, in very general terms, means that of the two genes present that code for a particular protein either one or both of them is different from the most common (or wild-type) gene.
This may lead to sub-optimal function of a receptor or abnormal production or degradation of neurotransmitters, and a huge array of metabolic effects.
The Role of Epigenetics
When one gene is different from the common wild-type form a gene is called a heterozygous variant, while if both genes are different it is called a homozygous mutation. In many situations there are multiple genes which serve similar functions in the body, and even with a homozygous variant it does not mean the body is unable to function.
And whether or not a genetic variant affects someone can be altered by epigenetics. Simply put, epigenetics is the environment inside the body. Factors affecting epigenetic transcription include illness, diet, chemical exposures, stress, and trauma among many other things.
The Use of SSRIs and NDRI
As medicine continues to further understand these genetic variants and how to support people based on their particular genetic code, treatments can someday be individualized based on what may be functioning sub-optimally on an individual basis.
Currently, for the treatment of conditions such as depression or anxiety the use of medications such selective serotonin reuptake inhibitors (SSRIs) or norepinephrine-dopamine reuptake inhibitors (NDRI) are broadly utilized, with many treatment failures as these medications may or may not be effective, and may have a broad array of side effects.
Practitioners of functional medicine and naturopathic medicine often use this specific genetic information to determine nutrient protocols that may be supportive to alleviate the symptoms of anxiety, depression, and obsessive compulsive disorder. With knowledge of which genes are functioning sub-optimally, specific nutrient protocols with agents such as amino acids, B vitamins, magnesium, and methyl donors may help support the body to function normally.
Oftentimes symptoms such as depression and anxiety can resolve with the use of nutritional support protocols, plus treatments for thyroid and hormone imbalance if these are also present. As these issues are often contributory to eating disorder symptoms, the knowledge of genetic variants and nutritional support protocols can be supportive for recovery from the eating disorder as well.
Different Types of Genetic Variants
Specific genetic variants that have been shown to be more common in individuals with bulimia nervosa involve several of the enzymes associated with neurotransmitters, as well as the methyl cycle. Specifically, genetic variants connected with bulimic symptoms include:
- catechol-O-methyltransferase (COMT), an enzyme which that degrades catecholamines such as dopamine, epinephrine, and norepinephrine2
- serotonin-transporter-linked polymorphic region (5-HTTLPR), an enzyme that codes for the serotonin transporter3
- oxytocin receptor (OXTR), a gene associated with social behavior4
Genetic variants associated with depression and anxiety include polymorphisms in genes associated with the metabolism of B vitamins5, MAOA and some of those previously stated.
How This Research Is Being Applied to Treatment
Some of this information is being utilized generally by physicians and psychiatrists as the medication Deplin® is a high dosage form of methylated folate which is an adjunctive prescription used with antidepressants. Although this is a prescriptive medication, lower doses of methylated folate are commonly used in nutritional therapeutic protocols.
The use of this nutrient has been shown to improve response of individuals to antidepressant therapies, particularly because one of the more common genetic variants found in individuals with anxiety and depression is that of the rate-limiting enzyme in the methyl cycle called methylenetetrahydrofolate reductase (MTHFR).
When this enzyme doesn’t function optimally, there is a “back up” in this metabolic critical cycle which functions thousands of times a second throughout the body, and there may be suboptimal folate status in the body. This can lead to accumulation of other metabolic intermediaries as well as systemic inflammation. Supporting the body appropriately with methylated folate eliminates dependence on the function of this enzyme, which is why the use of this nutrient has been found to be so therapeutic.
Getting a Genetic Test
Currently, there are companies through which individuals can order their own genetic tests such as 23andMe. Although this company is not allowed to provide health information directly, other resources are available online that process this information and provide specific information pertaining to genetics and nutrient support protocols which may be helpful.
Resources which may be useful for processing raw genetic information provided by 23andMe are companies such as MTHFR Support via Sterling’s App, NutriHacker, and Genetic Genie. Because this information is very in depth and at times may seem contradictory, consultation with a naturopathic doctor or functional medicine practitioner who is experienced in working with genetic data therapeutically is recommended.
With appropriate support for the body nutritionally, holistic healing can be achieved, reducing the need for prescription medications as well.
About the Author:
Dr. Carrie Decker is a board-certified naturopathic physician with the North American Board of Naturopathic Examiners, graduating with honors from the National College of Natural Medicine in Portland, Oregon. Dr. Decker works with clients locally in Wisconsin as well as distant regions via telemedicine (Skype or phone) services.
To find out more about Dr. Decker or naturopathic medicine, visit www.BlessedThistle.info or call 608.620.5831.
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- Kaye, W. H., Bulik, C. M., Thornton, L., Barbarich, N., Masters, K., & Price Foundation Collaborative Group. (2004). Comorbidity of anxiety disorders with anorexia and bulimia nervosa. Am J Psychiatry, 161(12), 2215-21.
- Donofry, S. D., Roecklein, K. A., Wildes, J. E., Miller, M. A., Flory, J. D., & Manuck, S. B. (2014). COMT met allele differentially predicts risk versus severity of aberrant eating in a large community sample. Psychiatry Research, 220(1), 513-518.
- Calati, R., De Ronchi, D., Bellini, M., & Serretti, A. (2011). The 5‐HTTLPR polymorphism and eating disorders: A meta‐analysis. International Journal of Eating Disorders, 44(3), 191-199.
- Kim, Y. R., Kim, J. H., Kim, C. H., Shin, J. G., & Treasure, J. (2015). Association between the Oxytocin Receptor Gene Polymorphism (rs53576) and Bulimia Nervosa. European Eating Disorders Review, 23(3), 171-178.
- Mitchell, E. S., Conus, N., & Kaput, J. (2014). B vitamin polymorphisms and behavior: Evidence of associations with neurodevelopment, depression, schizophrenia, bipolar disorder and cognitive decline. Neuroscience & Biobehavioral Reviews, 47, 307-320.
Last Updated & Reviewed By: Jacquelyn Ekern, MS, LPC on June 11th, 2015
Published on EatingDisorderHope.com