NICOLAESCU Oana Elena1, MOCANU Andreea Gabriela1, BELU Ionela1
1 Pharmacy Department I, University of Medicine and Pharmacy, 2-4 Petru Rares Str., 200349 Craiova, (ROMANIA)
Anxiety, also known as fear of the unknown, is according to WHO one of the most frequent mental disorders alongside depression and psychosomatic disorders.
Currently, a new approach is observed worldwide regarding the use of drug treatments in anxiety. Their various side effects determined a search for alternative solutions.
A special interest towards modifying the patient’s lifestyle in addition to drug therapy and cognitive behavioral therapy has been reported. An important link has been established between anxiety and diet. Therefore, researchers are trying to establish the biological mechanisms involved in the association between anxiety and nutrition. Nutrients such as omega-3 fatty acids, cobalamin, folate, zinc and antioxidants are considered to improve anxiety. Moreover, psychobiotics represent an effective approach as anxiety treatment.
Keywords: nutrition, anxiety, depression, antioxidants, diet, micronutrients, omega-3 fatty acids
The most frequent mental disorders worldwide are anxiety, depression and psychosomatic disorders according to World Health Organization (WHO). Anxiety is currently considered the second most important cause of premature death . In Romania, the frequency of anxiety disorders is 25-28%, whereas depression prevalence is 12-20%.
Anxiety is a complex and multifactorial process. As a result, a series of treatments and prevention directions can be considered. Martinsen and Raglin observe in American Journal of Lifestyle Medicine the importance of nutrition in anxiety . An inadequate nutrition may cause anxiety and depression and several studies show the importance of various nutrients in improving the wellbeing of an anxious patient .
The relationship between diet and anxiety is bidirectional. Not only may anxiety affect nutrient absorption, but also a deficient in certain nutrients may induce anxiety. Therefore, the so called “brain in your gut” refers to the link between the enteric nervous system (ENS) and brain and also between digestion, health, emotional state and even thinking process. Gershon et al mention that an inadequate function of an ENS process may be the cause or effect of a disorder associated with the central nervous system .
Definitions of anxiety
According to Roland Doron-Francoise dictionary, anxiety is defined as an emotion determined by the anticipation of an uncertain danger, difficult to predict and control. It transfers to fear when referring to an identified danger. It is usually associated with physiological and hormonal changes that characterize a heightened alertness state. Furthermore, it is correlated with the fight-or-flight response or avoidance behavior .
Anxiety disorders refer to phobias, panic attacks, anxiety attacks, obsessive compulsive disorders and post-traumatic stress disorder
Two definitions are mentioned for anxiety in the Larousse-Gener dictionary of psychology  Emotional state characterized by tension, heightened fear, poorly differentiated and often chronic
Predisposition of individual towards anxious disorders
According to American Psychiatric Association the criteria for identifying an anxious disorder are fear of the unknown, shortness of breath, palpitations, unjustified unrest, lack of focus, nervousness, feelings of suffocation, fear of going insane, fear of losing control, fear of height, fear of being exposed to a certain object or situation, leading to an avoidance behavior without any reason .
Developing an anxiety disorder is a complex process. Its etiology may be determined by an interaction between some susceptible genes and a series of biopsychosocial factors. The neurotransmitters involved in mediating anxiety are serotonin, dopamine, gamma aminobutyric acid (GABA) and noradrenalin.
Pharmacotherapy as well as psychotherapy can help cure anxiety. Treatment includes cognitive behavioral therapy, antidepressants such as selective serotonin reuptake inhibitors (SSRIs), pregabalin, used in generalized anxiety disorder, and short acting benzodiazepines.
Specific nutrients that may benefit anxiety disorders are vitamins such as folates, vitamin B12 and choline, minerals that include magnesium and zinc, omega-3 fatty acids, tryptophan (serotonin precursor) and antioxidants such as vitamin E, C, carotenoids and flavonoids. Several studies show the involvement of serotonin, tryptophan and melatonin in anxiety disorders . Furthermore, psychobiotics represent a new direction for anxiety treatment .
Serotonin, tryptophan and melatonin
Tomatoes, bananas, pineapples, prunes and kiwis are foods that help increase serotonin levels. Melatonin is contained by foods that include goji, fenugreek and both black and white mustard seeds. Moreover, foods such as eggs, tofu, turkey salmon, nuts, cheese are reach in tryptophan [10,11].
Omega-3 fatty acids
The nutrients most reported to be linked with anxiety are omega-3 fatty acids. They are long- chain polyunsaturated fatty acids, represented by alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Alpha-linolenic acid is an essential fatty acid because it cannot be synthesized in the organism; food is its main source. ALA can be converted in the body into EPA and DHA, but a low quantity is obtained (less than 5%). Food sources include fatty fishes such as tuna, salmon, herring and mackerel and fish oil which contains 18% EPA and 12% DHA. Fish oil concentration in fatty acids goes up to 33% for EPA and 22% for DHA. ALA is found in high concentrations in flaxseeds, walnuts, soybeans and rapeseed.
Marine algae are currently another important source of omega-3 fatty acids. They include microalgae such as Crypthecodinium cohnii and Schiyochytrium. EPA and DHA are critical in brain development and function as well as reducing the risk of cardiovascular conditions [12,13] and developing certain types of malignant tumors, neurological disorders  or diabetes complications . Moreover, they have a positive effect in cardiovascular conditions. Omega-3 fatty acids are essential in eicosanoid synthesis. Eicosanoids regulate a variety of biological functions that includes the serotonergic system known for its role in modulating behavior. Thus, explaining the link between omega-3 fatty acids and anxiety.
Studies show that a diet low in fish or a decreased tissular level of omega-3 fatty acids translate into a predisposition for anxiety and even depression .
Micronutrients may also cause anxiety according to various studies. They include vitamin C, thiamine, niacin, pyridoxine, cobalamin, folate (vitamins C, B1,B3, B6, B12) and minerals such as zinc or selenium.
Low levels of folates and cobalamin (vitamin B12) have been correlated with anxiety and sustaining the anxiolytic treatment response, according to previous reports . Their biological effect is determined by their intervention in both function of the nervous system and carbon metabolism. Furthermore, they may increase the plasmatic level of homocysteine which is associated with depression and anxiety .
Food sources of folates and cobalamin are represented by asparagus, spinach, beans, lettuce, cereals, broccoli, sunflower seeds, orange juice, lentil and turnip.
Zinc concentration in the brain is high, with several effects in neurotransmissions. It is an essential mineral for hundreds of body enzymes, including several that are involved in antioxidant processes. Zinc has been linked with anxiety and depression in various reports , although its mechanism of action has not been completely established.
A wide variety of foods such as oysters, chickpeas, veal, pacific halibut and crabs are high in zinc
Kava – a crop of Western Pacific
Kava is the extract of Piper methysticum, a plant that originates in the Pacific Islands. It may relax muscles, improve mood, reduce pain, induce a calming and highly anxiolytic effect. Kava has proved to be very useful in treating anxiety disorders in numerous double-blind studies, having a high efficiency compared to placebo. According to these studies its effect was similar to classic anxiolytics .
They represent a group of nutrients that protect against oxidative processes. Studies show that they have an important effect in preventing and treating anxiety . They include vitamin C, vitamin E, selenium and carotenoids. Various plants, cereals, fruits and vegetables are rich in antioxidants. Their involvement in reducing anxiety is still being researched.
Psychobiotics represent a different approach for anxiety therapy. They are living microorganism that, when ingested in proper quantities, benefit the psychiatric patient, according to a study in Biological Psychiatry . This probiotic class produces neuroactive substances such as serotonin and GABA that modulate the gut-brain axis. Preclinical tests suggest that several psychobiotics may have an anxiolytic effect. These psychobiotics appertain to the Bifidobacterium and Lactobacillus genera which are known to improve anxiety symptoms .
Fermented foods such as kefir, kimchi, pickled cabbage are a source high in probiotics.
Psychopharmacological strategies and complementary psychotherapies may have a moderate effect and a high relapse risk for most patients. Current scientific reports show that psychiatric disorders are determined by multifactorial pathogenies, including genetic factors, inflammatory factors and neurotransmission imbalance. Furthermore factors that are associated with lifestyle are becoming more and more important. According to various studies, nutrition plays a key role in maintaining a mental health.
More studies are required to completely establish the relationship between nutrition and anxiety and to determine their mechanism of action. However, literature mentions that a poor diet may be correlated with anxiety symptoms. Dietary interventions seem to reduce anxiety. Furthermore, and are cheap, safe and easily accepted by patients. In most cases, patients have better compliance towards diet changes rather than drug treatment. Another important aspect is that the medical personnel acknowledge the importance of diet in anxiety treatment and prevention.
In conclusion a diet rich in good nutrients and without unhealthy foods is the key to a healthy body and mind.
Author Contributions: All authors have equally contributed to the work reported.
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