The Role of Diet in Mental Health – A Review of the Latest Research

There is increasing evidence that what we eat can have an impact on our mental health, particularly through diet. Studies suggest that eating less ultra-processed food and more fruits, vegetables, fish, lean meats, nuts seeds and healthy fats may reduce depression and anxiety risk factors.

If you are interested in making changes to your diet, consulting an Accredited Practising Dietitian (APD) may help provide tailored nutritional advice.

Eating Disorders

Not only can a healthy, nutrient-dense diet impact mental health; other factors can have just as great an effect. Consuming more foods rich in fiber, vitamins and minerals may help alleviate depression symptoms; furthermore, studies have demonstrated that those eating higher quality diets like those recommended in Mediterranean, Japanese and Norwegian diets tend to be less likely to experience depression than others.

People who are dissatisfied with their body are at an increased risk for an eating disorder such as anorexia nervosa (AN), bulimia nervosa (BN) and binge eating disorder (BED). Some individuals also may develop eating disorders that do not meet diagnostic criteria for these diagnoses, such as other specified feeding or eating disorders (OSFEDs).

Researchers are investigating what people perceive to be the causes of eating disorders in order to better understand and develop treatment solutions. One study discovered that participants with an eating disorder typically identified psychological/emotional problems as the root of their illness while those without one often pointed toward media/culture ideals as contributing.

Depression

The brain is an extraordinary organ, but it needs premium fuel to function optimally. When individuals consume foods low in nutrients or contain potentially toxic chemicals, both their bodies and minds may suffer – this underscores why nutrition plays a crucial role in mental wellbeing.

Researchers are expanding their study of diet and depression. They’re discovering that eating a well-rounded diet with adequate protein, antioxidants and omega-3 fatty acids helps lower risk of depression; conversely, such an approach can also alleviate symptoms in those already living with these conditions.

Studies are increasingly showing that eating too many processed foods can worsen depression and trigger or intensify certain eating patterns. This has given rise to nutritional psychiatry – the field that explores relationships among food, feelings and the gut microbiome.

Anxiety

Anxiety disorders are among the most prevalent mental health conditions worldwide and one of the primary sources of disability. Research indicates that better nutrition may lower risks associated with anxiety and depression.

Western-like diets increase the likelihood of anxiety disorders through various gut microbiome dependent mechanisms, including autonomic nervous system modulation, altered intestinal mucosal barrier function changes, production of metabolic byproducts from bacteria metabolism processes, changes in dietary composition and inflammation (see figure 1).

Multiple studies have demonstrated the link between eating ultra-processed food with high amounts of sodium, added sugars, saturated and trans fats as well as food insecurity and anxiety symptoms. When people don’t have access to healthy food sources they may turn to comfort foods which provide short-term satisfaction but lack nutrients – worsening mood and contributing to an anxiety disorder. Furthermore, chronic stress and low grade inflammation may further exacerbate anxiety symptoms.

Obesity

Studies indicate that obese individuals are more prone to depression and have reduced quality of life compared with their non-obese peers. Obesity can also decrease one’s social connections, leading to feelings of isolation which in turn worsen their mental wellbeing.

Researchers conducted a longitudinal study among European adults aged 50 years or older and discovered a bi-directional relationship between weight gain and depression scores in Wave 4, as well as BMI and quality of life in Wave 8. Neither age nor sex factors altered these associations, however.

Diet is known to play a vital role in improving mood. One study demonstrated this through high-quality diets significantly reducing depressive symptoms among individuals suffering nonclinical depression. Meanwhile, another one discovered dietary interventions improved depression for people diagnosed clinically; though these findings have not been replicated by subsequent research.