By: Dr. Colin O’Brien ND, Medical Doctor, Cyto-Matrix
Depression and anxiety are conditions that affect us all, either personally or through the suffering of friends, family and patients. While there are a seemingly endless number of factors to consider that are unique to each individual, one area that should always be addressed is nutritional status.
Anecdotal evidence and clinical research has shown us that mental health concerns can arise in the presence of single or multiple nutrient deficiencies. Here is a brief summary of some of the most common nutrients to consider when treating mental health:
Magnesium: Although we typically associate magnesium with musculoskeletal function, it has been shown to increase brain-derived neurotrophic factor (BDNF) and GABA, while down-regulating ACTH and blocking NMDA receptors. Benefits for improving depression markers have been seen with supplementation after only 1-2 weeks in many different forms (such as oxide, glycinate and taurinate). Although clinical trials have shown benefits for depression and anxiety between 125-300mg of elemental magnesium per day, clinically it may be most useful to dose to bowel tolerance.
Zinc: The hippocampus, the area of the brain responsible for emotion, memory and motivation, has one of highest concentrations of zinc in the body. Many studies have shown that lower zinc levels are associated with depression, and interventional trials support its use for this purpose. Specifically, zinc sulphate has successfully been used in Multiple Sclerosis patients and zinc gluconate has been used in obese patients, with both improving Beck Depression scores after 12 weeks. The evidence based dose is 25-50mg of elemental zinc per day and zinc supplementation can also safely improve SSRI outcomes.
B-vitamins: A 2015 Systematic Review found that B12 and Folate reduced the onset and relapse risk for depression with long-term supplementation. Similarly, a combination of 500mcg vitamin B12, 2mg Folate and 25mg vitamin B6 has been shown to improve antidepressant medication response over a full year. Clinically, a well-balanced B-complex supplement or intramuscular methylcobalamin and folate injections can have an immediate positive impact on mood and energy, if patients have suboptimal levels. I prefer my mental health patient’s serum B12 levels to be above 500 pmol/L.
Iron: Iron is not only needed for hemoglobin synthesis, but also serotonin production and the proper conversion of thyroxine (T4) to triiodothyronine (T3). Although no interventional studies have been done with iron and depression or anxiety, there is a strong and convincing correlation noted between low hemoglobin and depression with a dose-response relationship, meaning those with worse anemia demonstrate more severe depression. Ferritin levels below 45 ng/mL and hemoglobin below 120 g/L for women (less than 130 g/L for men) are associated with depressive symptoms
Vitamin D: Higher serum levels have been associated with a 43% lower risk of depression and panic disorder, with various interventional trials showing benefits for depression with a wide range of dosing (ie 50,000 IU/week vs. 2,000 IU/day). Similarly, benefits for vitamin D supplementation in depressed adolescent females, obese populations and perinatal mothers has been demonstrated. However, there are also many interventional trials showing lack of benefit which could be due to adequate vitamin D status in subjects at baseline. The target blood levels for optimal mood should be 75 nmol/L or greater.
Omega-3’s: A 2018 analysis of 19 RCTs found that fish oil supplementation provided a modest improvement in those with anxiety, with a greater effect in those taking more than 2,000mg/day of combined EPA and DHA. When it comes to depression, some evidence has shown that it is not beneficial to simply restore polyunsaturated fatty acid (PUFA) status in the body, but rather that omega-3’s can be beneficial in cases of systemic inflammation. In fact, your depressed patients are most likely to respond to omega-3 supplementation if their high sensitivity C-reactive protein (hs-CRP) is above 3.0. The evidence based dosage in depression is 1000-2000mg of EPA per day.
Selenium: Time to eat those brazil nuts! There are at least 5 studies associating low selenium with depression & anxiety, while one interventional study of 100mcg/day improved mood after only 5 weeks.
When it comes to choosing the right nutrient(s) for supplementation, lab testing, clinical signs and symptoms, and knowledge of common medication depletions should be considered. But the take home message from all of this should be that, when it comes to mental health, diet matters…a lot. There are many nutrients necessary to keep the brain balanced.
Perhaps the best study to illustrate this was the 2017 RCT of 67 individuals with moderate to severe depression. After 12-weeks of eating a modified Mediterranean diet, 32% went into remission compared to only 8% of the control group. The key here is that the dietary intervention was ad libitum, meaning the focus was on food quality and not calories. The group was even allowed up to 3 servings per week of “extras” such as refined sugars, alcoholic drinks and fast-foods, showing that it doesn’t need to be an “all-or-none” approach.
Even encouraging patients to “Eat the rainbow” to get a wide variety of nutrients and to focus on “Eating whole foods” to reduce sugars and additives is often an easy starting point for many individuals that feel overwhelmed with dietary changes. In fact, simply reducing the glycemic index of foods can reduce the risk for depression.
When it comes to mental health, part of the solution for our patients may be simpler than we think. In the words of Michael Pollan, “Eat real food. Not too much. Mostly plants.”
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