Can Appropriate Nutrition Positively Affect Anxiety?
Anxiety comes in a myriad of forms from social anxiety to post traumatic stress disorder with an average onset at 11 years of age. Anxiety is estimated to affect 18% of the US population or 42 million Americans with 4% of the population suffering with severe anxiety. , 
The more common and easily identifiable symptoms of anxiety include a feeling of dread, edginess or irritation, fear, worry, difficulty with concentration and focus; somatic symptoms may include increased heart rate, nausea, sweating, blushing, shortness of breath, coldness, numbness and trembling. However, less obvious symptoms may need to be coaxed out of the patient through key questioning during a clinic visit. These include inquiries on feeling overwhelmed, helpless or depressed; changes in relationships or career status; and financial and social hardships caused by the anxiety.
Current management options consist of both preventive and therapeutic routes including medication and counseling. There are a variety of pharmaceutical interventions such as anti-depressants, with selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs) or tricyclic antidepressants being the most common. Other pharmaceuticals utilized for anxiety disorders are antihistamines or beta blockers and more recently, certain anticonvulsant medications and, benzodiazepines for acute anxiety symptoms.
There may be drawbacks to using pharmaceuticals in some cases. These include potential for increased risk of suicidal thoughts or tendencies, insomnia, mania, aggression and potentially a worsening of anxiety or depressive symptoms. In some cases, combining certain SSRIs or SNRIs with other medications can create a life-threatening condition called serotonin syndrome leading to hallucinations, abnormal changes in blood pressure and elevated temperature.  Although there is value in having the options of these pharmaceutical approaches, the potential side effects or risk of combinations can worsen the situation. Psychotherapy, counseling and biofeedback are often coupled with pharmaceutical recommendations for a more holistic approach and, more recently, interest has been sparked on the relationship between nutrition and risk of anxiety.  Emerging research indicates that overall dietary patterns can correlate with anxiety symptoms and that a higher Western food consumption has been associated with an increased risk for anxiety disorder by approximately 25-29%. 
Key Points: A recent blog by Drew Ramsey, MD reviews data surrounding the addition or elimination of specific nutrients and foods for reducing anxiety symptoms in patients. The nutrients and foods which he discusses include choline, fermented foods, omega-3 fatty acids, gluten and sugar.  The findings from Dr. Ramsey’s blog are summarized below.
- Choline is a nutrient classified in the B vitamin category and found in high levels in eggs, many green vegetables, meats and seafood. Choline is utilized by the body in the various capacities including the methylation system, nervous system and membrane structure. The Hordaland data set, a large epidemiological data set from Scandinavia, found that patients in the lowest tertile of choline consumption had approximately a 33% higher risk of having anxiety disorder. 
- Fermented foods, rich in probiotics, influence changes in the microbiome, a crucial component in the gut-brain connection. Recent clinical trials looking at the effects of probiotics on mood and brain health found a reduction in anxiety over a 30 day trial in those taking probiotics. ,  Another study utilized MRI imaging to compare individuals who ingested fermented dairy products on a daily basis against control subjects. Results from this study indicated changes to brain circuitry in those ingesting the fermented foods. This dietary habit may positively impact anxiety symptoms through alteration of somatic senses and emotional processing. 
- Omega-3 fatty acids have often been associated with improving brain function. Participants taking 2.5 grams of long chain omega-3 fats (2 grams of EPA and 0.5 grams of DHA) showed nearly a 20% reduction in anxiety after taking the supplement as assessed by the Beck Anxiety Inventory scale.  Increasing consumption of fatty fish such as salmon, herring, albacore tuna and sardines is one way to augment omega-3 fatty acid intake.
- Anxiety is a frequent complaint in patients with Celiac Disease (CD) although a recent meta-analysis of the literature does not indicate that anxiety is more common nor more severe in patients with CD than in control patients without CD.  However, researchers interested in learning if a gluten free diet could lessen the severity of the anxiety symptoms in CD patients, conducted a one year study to learn more. The researchers followed 35 patients with celiac disease who were placed on a gluten-free diet for one year. Assessments included the State-Trait Anxiety Inventory (STAI). At baseline, 72% of participants were positive for significant levels of anxiety; this dropped to 25% at the end of the trial. For comparison, 24% of the 59 participants in the healthy control group reported significant levels of anxiety at baseline and no significant change was reported in their anxiety at the end of the trial. 
- Sugar intake can lead to both hyperglycemia  as well as latent hypoglycemia, both of which can impact anxiety. Practicing a whole foods diet over high sugar or highly processed foods may lead to improved outcomes for those suffering from anxiety. Further research is needed to understand the specific impact each nutrient has on brain health but overall the research favors moving towards a whole foods diet for those with anxiety.
Why is this Clinically Relevant?
- A whole foods diet rich in omega 3 fatty acids, choline and fermented foods may reduce anxiety
- A whole foods diet low in processed foods and sugar may lower anxiety severity
- A gluten free diet in patients with celiac disease can reduce levels of anxiety
 National Institute of Mental Health. Anxiety Disorder in Adults; https://www.nimh.nih.gov/health/statistics/prevalence/any-anxiety-disorder-among-adults.shtml Accessed 6/15/2017
 National Alliance on Mental Health. Mental Health by the Numbers; https://www.nami.org/Learn-More/Mental-Health-By-the-Numbers Accessed 6/15/2017
 National Institute of Mental Health. Mental Health Medications. https://www.nimh.nih.gov/health/topics/mental-health-medications/index.shtml Accessed 6/19/2017
 WebMD. Generalized Anxiety Disorder; http://www.webmd.com/anxiety-panic/guide/understanding-anxiety-treatment#3 Accessed 6/15/2017
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Link to Summarized article: How Diet Influences Anxiety