Nutrition prevents anxiety and depression in women

A diet rich in B vitamins, omega 3 and antioxidants helps protect mental health and well-being. This relationship is especially evident in women who faithfully follow healthy eating guidelines, for whom a 49% lower chance of suffering from anxiety and 45% lower chance of depression was found, compared to those who do not follow a healthy diet. Similarly, young people up to age 40 with proper eating habits have a more than 50 percent reduced risk of being affected by anxiety disorder and depressive disorder.

This is according to a study conducted by researchers at the University of Isfahan (Iran) and published recently in the British Journal of Nutrition.

Anxiety and depression are related to lifestyle

Psychological disorders such as depression and anxiety represent major public health problems worldwide. Depression negatively affects health status, quality of life, and ability to work and contributes to many disabilities, chronic diseases, and mortality. Anxiety disorder is also often accompanied by somatic symptoms such as fatigue, loss of energy, feeling slowed down or agitated. The etiology of depression and anxiety is not fully known, however, several environmental, psychological, and genetic factors may contribute to these conditions. 

Some risk elements that can be modified by changing lifestyle including obesity, physical inactivity, smoking, and poor diet appear to be in association with mental disorders. Several studies have examined modifiable lifestyle elements linked with some mental illnesses, but most have focused on the relationship of a single misbehavior, rather than with lifestyle as a whole. In contrast, an investigation of the famous National Health and Nutrition Examination Survey (NHANES) study examined associations between dietary behaviors, physical activity, and smoking habits as independent risk factors for depression.

The results revealed a dose-response relationship between the simultaneous occurrence of these attitudes and depressive symptoms, however, obesity and psychological distress, two of the major risk factors for mental disorders, were not considered. Some previous research has shown a protective association between adherence to healthy eating guidelines and mental disorders in Western nations, while data are scarce for other parts of the world such as the Middle East, where due to cultural factors women engage in less physical activity than men.

Healthy eating: those who follow it suffer less from mental disorders

In the new study, researchers examined the association between adherence to Iranian healthy eating guidelines, as measured by the Alternative Healthy Eating Index (AHEI-2010), and the prevalence of anxiety and depression in healthy adult subjects. The AHEI-2010 index assesses the "healthiness" of a diet, measured by considering the intake of 11 food and nutrient groups: fruits, vegetables, whole grains, legumes, nuts and omega-3s (DHA and EPA), alcohol, sugary drinks and juices, red and processed meats, saturated fats, and salt. Results showed that higher adherence to AHEI-2010 was associated with lower rates of anxiety and depression particularly in women, for whom a 49 percent lower chance of suffering from anxiety and 45 percent lower chance of suffering from depression was shown, and in young people up to age 40 who showed a 58 percent and 51 percent reduced risk of suffering from the two common mental disorders, respectively. 

B vitamins, antioxidant molecules, and omega-3 polyunsaturated fatty acids are potential elements involved in mental well-being, according to researchers. The authors of the research hypothesized several options to explain the link between a healthy diet and better mental health: high content of folate and other B vitamins, and antioxidants could reduce the damage of neurons caused by free radicals (oxidative stress). In addition, another possible neuroprotective mechanism may be due to the high levels of omega-3 present in fatty fish, in agreement with other studies carried out in recent years.

In particular, the anti-inflammatory properties of some of the foods included in AHEI-2010 could reduce concentrations of substances, monoamines, found in certain foods that can act negatively on the nervous system.

Some details of the study

The research, conducted in two phases, was carried out as part of the "Study on the Epidemiology of Psychological-Alimentary Health and Nutrition," a project involving Iranian adults employed in 50 health centers affiliated with Isfahan University. Researchers during the study assessed the adherence to healthy eating of 3663 adults who filled out two questionnaires: one, the AHEI-2010, on eating behaviors such as frequency of consumption of certain foods and their portions; the other, the Iranian version of the Hospital Anxiety and Depression Scale, used to identify participants affected by anxiety and depression. 

The prevalence of anxiety disorder was, on average, about 15 percent (10.8 percent of men and 18.3 percent of women), while depression was found in 30 percent of participants (22.9 percent of men and 35.1 percent of women). Individuals who ate the most fruits, vegetables, whole grains, nuts, legumes, and omega-3-rich fish received a score of 10, and those who consumed the lowest amount of these foods had an AHEI-2010 index score of 1. Those who ranked higher on this scale, who therefore followed the correct diet more closely, were found to be mainly women and more highly educated individuals, compared to those placed at the bottom of the scale.

Mental health and healthy eating, a more frequent relationship among women

Adherence to healthy eating was found to be inversely associated with the likelihood of anxiety and depression in adults. When the relationship was analyzed separately for men and women, the association was found to be significant in women, but not in men, probably due to the low frequency of anxiety and depression cases found among male subjects. According to the same researchers, therefore, a larger cohort study will be needed to provide evidence of a relationship between healthy eating and mental health. 

Source: Parvane Baneei, et al. "Adherence to Alternative Healthy Eating Index In relatlon te depress/on and anxlety In lran/an adults": British Joumal of Nutrition.