Depression affects up to 23% of the world’s population each year and is ranked among the top 5 leading causes of disability worldwide. Psychotherapy and pharmaceutical medications are the mainstay of traditional treatments for depression, but if these haven’t worked for you or a loved one, don’t give up! Functional medicine approaches to treating depression can significantly improve mood and focus on identifying the root cause of depression.
Signs & Symptoms of Depression
The National Institutes of Mental Health defines depression as “a period of at least two weeks of depressed mood or loss of interest in daily activities. As well as as problems with sleep, eating, energy, concentration, or self-worth.” This can show up differently for many people. For some, it looks like lying in bed and feeling like they no longer want to see friends or work. For others, it can look like eating more and finding themselves more tearful or irritable than normal. Depression also varies in severity and can be mild or debilitating. Thankfully, there are many effective ways to treat it, no matter how it shows up.
Possible Causes of Depression
A number of nutrient deficiencies are linked with depression, including deficiencies in B vitamins like cobalamin (B12), folate (B9), pyridoxine (B6); minerals like zinc, selenium, magnesium, iodine, copper, and calcium; and other nutritional compounds like amino acids, antioxidants, vitamin D and omega 3’s. This list is not exhaustive. In fact, over 20 different nutrient deficiencies have been linked with depression!
If you’re like many, you may be thinking that it’s unlikely that you have a nutrient deficiency, particularly if you’re overweight or regularly consume enough total calories.
But research indicates that Americans are significantly deficient in many critical nutrients due to a nutrient-poor diet. For example, 90% of people with obesity are deficient in vitamin D - a nutrient that is directly linked with depression and seasonal affective disorder.
Abnormalities in the hormone cortisol, thyroid hormone, estrogen, progesterone, testosterone, DHEA, and neurohormones like serotonin, dopamine, and norepinephrine are linked with depression.
Having hypothyroidism, for example, can lead to depression and other symptoms like weight gain, hair loss, fatigue, and bloating.
Minerals and Heavy Metals
Minerals (also known as metals) create electricity in the body. Our brains use electrical signals to communicate with our muscles, tissues, and organs and help release and transport neurotransmitters.
Having a mineral deficiency like iron-deficient anemia can absolutely result in a depressed mood. However, having too many metals or minerals is not a good thing either. Excessive levels of heavy metals like aluminum, lead, or mercury can cause depression, cognitive issues, and other mental health and brain-based disorders.
Food Allergies and Sensitivities
Food allergies that are mediated by IgE immunoglobulins and histamine reactions can cause depressed mood by altering blood flow to the brain. Similarly, IgG and IgA food sensitivities and food intolerances can impact mood. Celiac disease, for example, is an IgG / IgA immune intolerance to wheat that is linked with depression and other mood disorders.
Functional Medicine Labs to Find the Root Causes of Depression
Testing for Micronutrient Deficiencies
There are several ways to assess for nutrient deficiencies, including collect-at-home blood spot tests, blood draws, nutrient profiles that look at cell contents, and more. Even a standard CBC and CMP that your doctor runs every year at your check-up can detect some B vitamin and iron deficiencies.
Testing for Hormone Imbalances
Testing for Heavy Metals
Practitioners can check hair, blood, and urine to detect heavy metal abnormalities. If findings are normal, but you still suspect you may have heavy metal toxicity, another option is a provocation challenge test. This type of test requires taking a small dose of a heavy metal chelator and then checking how much of that metal is excreted into the urine.
Testing for Food Sensitivities
When assessing food allergies and food sensitivities, there are blood spot and blood draw collection kits that your practitioner can use to find the foods that you may be reacting to. An important point to note is - for food sensitivities - you actually have to have eaten the food in the last two weeks (preferably three days) for your body to make enough immunoglobulins to detect a reaction. Ask your practitioner for more information if you’re confused about this.
Functional Medicine Treatment for Depression
The treatment for your unique form of depression will determine your root cause. If you have a nutrient deficiency, your practitioner will help you design either a food-as medicine plan or prescribe a supplement to help replete you.
If your issue is hormonal, your clinician will prescribe hormone replacement or work to eliminate the barriers to normal hormone production using a combination of lifestyle, nutrients, herbs, and even pharmaceuticals.
If you have a food allergy or sensitivity, your practitioner will work with you to properly eliminate all IgE mediated responses (allergies) and eliminate and reintroduce IgG mediated responses (sensitivities) while still ensuring that you get proper micronutrient needs. Some practitioners will refer out to Integrative Nutritionists.
Many people are curious if “natural medicine” can be used instead of pharmaceuticals to treat depression. For many people, the answer is yes. For others, natural medicine makes a great addition to their existing treatment plan. A great example is taking folic acid or folate with an SSRI to increase the effectiveness of the SSRI. Your unique plan will be a combination of whatever works best for you, whether it’s pharmaceuticals, meditation, food, sleep, or movement.
There are many root causes of depression that a functional medicine practitioner can help you detect, treat and heal. These include nutrient deficiencies, hormonal imbalances, food allergies and sensitivities, and many more.
A skilled practitioner can help you find your individual root cause and heal your depression naturally if you choose so that you can get back to feeling happy, healthy, and in love with your life.
*Special thanks to Dr. Kate Henry's naturopathic assistant, Lindsey Bevilacqua, for her help with this article.
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