It’s been known for a long time that what a person eats and drinks can have a significant impact on their physical health. The connection between diet and nutrition and someone’s mental well-being, however, is only just starting to be understood.¹ 
 
This article looks at why diet and nutrition are important in relation to schizophrenia, why adopting healthier eating behaviours is important, and presents current advice on what people living with schizophrenia should and perhaps should not eat.

First, what’s the difference between diet and nutrition? Diet refers to the foods and drinks that someone ingests on a regular basis whereas nutrition refers more to the quality or kind of those foods or drinks. ¹ 

Studies have shown that some people with schizophrenia have poor dietary patterns and eating habits when compared with the general population.^3,4 
 
This may include eating more sugary or fatty foods, which are often high in calories, rather than choosing healthier options such as fresh fruit or vegetables.³ Moreover, it may include skipping meals such as breakfast, preferring convenience foods over home-made cooking, eating snacks in the evening rather than eating a proper meal, and eating too quickly.³ 
 
This is important because over time this will lead to a poor nutritional state, which in turn is linked to 
being overweight, obesity, type 2 diabetes, heart disease, stroke, and cancer.^4,5 Even more importantly for those with schizophrenia, poor nutrition can affect brain function,⁵ and a poor nutritional state has even been linked to the development of psychosis.³
 
Eating a healthy diet is therefore an important lifestyle component for those living with schizophrenia, together with performing suitable levels of physical activity, stopping smoking, and moderating alcohol intake.   

There is some evidence to suggest that certain vitamin and mineral deficiencies may be important in people with schizophrenia and that reversing these deficiencies may be benefical.⁷ 
 
Of all the vitamins, the most beneficial appear to be the B vitamins, notably B₆, B₉ (folate) and B₁₂, although vitamins C, D, and E, have been linked to improved symptoms and better cognitive function.^3,7 
 
Among the minerals, zinc has been shown to be beneficial in reducing both the positive and negative symptoms of schizophrenia.^3,7 

There is no specific schizophrenia diet, and the consensus is to follow dietary recommendations for the general population.^2,3,6 This includes eating at least five portions of fruit and vegetables a day, basing meals on starchy carbohydrates, such as potatoes or rice, and including some protein, such as fish, meat or alternatives, beans and pulses.^2,6 
 
Importantly, it includes cutting down on foods high in sugar, fat and salt, ^2,6 a recommendation that is supported by a recent analysis of all available studies looking at diet and nutrition in schizophrenia.³ According to this research, food to avoid includes refined sugar, sugar-sweetened drinks and confectionary, as well as refined grain products such as sugary cereals, white bread, and pasta.³ 
 
Conversely, foods to consider including more of in the diet are³ 

We’re only at the beginning of understanding how nutrition affects our mental health and more research needs to be done. If a change to the diet sounds like a good idea for you or a loved one, then remember that you have the support of your healthcare team if you need it. They may be able to suggest simple behavioural changes such as eating three meals a day or be able to refer you to a   nutritionist who specializes in mental health issues. 
 
Finally, before taking any supplements, be sure that they will not affect any medications that you may be taking – always check with a doctor or pharmacist first.