A new expert study confirms that diet significantly affects mental health. There is ample evidence of an association between poor diet and worsening of mood disorders, including anxiety and depression. However, many common beliefs about the health effects of some foods are not substantiated.
The researchers found that in some cases, the link between diet and mental health was well established, such as the effects of a high-fat, low-carbohydrate diet (ketogenic diet) on children with epilepsy and the effects of vitamin B12 deficiency on fatigue, poor memory and depression.
There is also ample evidence that a Mediterranean diet, rich in vegetables and olive oil, reduces depression and anxiety. While many foods or supplements, such as vitamin D supplements or foods that may be associated with Attention Deficit Hyperactivity Disorder or Autism, have no effect on depression or anxiety.
This study confirms that although some foods may be associated with a mental health condition, it does not tell us why this food has this effect and should be considered in future nutritional psychiatry research.
The effect of diet on mental health is real, but we must be careful to draw conclusions based on temporary evidence. We need more studies on the long-term effects of daily diets.
Scientists have confirmed that the effects of some foods on mental health are easily proven, for example, nutrition in the womb and early in life can have significant effects on future brain function.
 
 

Diet and mental health

In the twentieth century, with a significant increase in the consumption of sugars, snacks and high-energy foods, major changes occurred in the consumption of diets worldwide. At the same time, the consumption of nutrients and rich in fiber is declining. In fact, the latest data from our global study show that unhealthy diet is now the leading cause of premature death.

Unhealthy eating patterns and increased consumption of processed foods are associated with increased depression and often anxiety.
An observational study found that a healthy diet reduces the risk of depression in diabetics.
Depression is not just a brain disorder, but a disorder of the whole body that is associated with dysfunction (chronic and low-grade systemic inflammation) as a major risk factor. Environmental stressors that are effective in causing systemic inflammation are:

• Improper diet

• Lack of exercise

• smoking

• Overweight and obesity

• Lack of sleep

• Vitamin D deficiency

• Stress

Many of these factors affect the gut's natural bacteria, which in turn weaken the immune system.
 Inadequate consumption of nutrient-rich foods can lead to a lack of nutrients, antioxidants and fiber, and this has a devastating effect on our immune system.
A diet high in saturated fats and refined sugars has a negative effect on brain proteins that we know are important in causing depression. Proteins called neurotrophins protect the brain against stress and stimulate the growth of new brain cells.
There is a clear relationship between the quality of adult’s diet and the size of their hippocampus.
Animal experiments have shown that foods high in saturated fat and refined sugar are addictive and interact with the dopamine system.
The World Health Organization has long said that "there is no health without mental health."
The omega-3 fatty acids in fish appear to be beneficial for people suffering from major depression.
Zinc or vitamin B supplements may be helpful.
There is also an amino acid called N-acetyl cysteine or NAC, which is especially useful for people with depression, schizophrenia and bipolar disorder.