“This field is nascent, but booming,” Naidoo says. “Focusing on nutrition to optimise brain health and, in doing so, preventing and treating mental health concerns such as anxiety, depression, insomnia, ADHD [attention deficit hyperactivity disorder] and fatigue is the key.”

The idea of food as medicine is the key to nutritional psychiatry, and does not exclude the use of prescription medications. A recent study, published in the International Journal of Environmental Research and Public Health, has outlined positive and negative associations between diet and depression.

“With around 40 trillion microorganisms, the gut is the largest endocrine organ in the body,” Naidoo says, “and by communicating to the brain via the vagus nerve [the largest nerve in the autonomic nervous system], regulating hormones and influencing inflammation, the gut can impact mental health.

“Before we were even born, our gut and brain developed from the same cells, and they remain connected throughout our lifespan, by the vagus nerve.”

Dr Drew Ramsey, a psychiatrist and author, founded the Brain Food Clinic in New York to treat and counsel people with depression, anxiety and emotional wellness concerns.

In his book, Eat to Beat Depression and Anxiety, he describes the growing evidence for the connection between food choices and mood and anxiety disorders, and why it’s critical for doctors to inquire into their patients’ diets, and recommend foods that best nourish the brain.

Naidoo says: “Gut inflammation is brain inflammation and what’s good for your gut is also good for your mental health.”

Covid-19 and mood foods

Case study

Naidoo describes a patient we will call Beatrice to protect her privacy. The 39-year-old woman lived with her dog in Boston in the US and had been referred to Naidoo by her gastroenterologist.

Beatrice had been promoted at work 18 months before, and had gone from living at home, walking her dog and going for a run daily, and preparing most meals and lunches for work at home, to travelling most days of the month.

“She had begun eating for convenience. Since she exercised regularly she had not gained significant weight, but her meal quality had plummeted. Between airline snacks, airport fast food and late-night snacks in hotels, she was simply eating very differently.

Since she had business meetings almost every night, she was drinking one or two glasses of wine at night, compared to perhaps one glass at a weekend dinner with friends. She was experiencing heightened anxiety which she thought was related to work stress.”

Naidoo concluded the issue was gut inflammation related to poor diet. The treatment plan included healthy, nutrient-rich meals including snacks for travel with fresh fruit, raw nuts and some plain chocolate. Beatrice would reinstate her meditation practice, building it up from five minutes, twice a day, and do yoga and breathwork exercises.

Body intelligence and mindfulness

Body-oriented therapist and author Ann Todhunter Brode explained the concept of body intelligence in her book, A Guide to Body Wisdom. Each body has a unique and powerful way it thinks, communicates, thrives and heals, she writes.

Naidoo says an important aspect of mental well-being is mindfulness and the capacity to acknowledge how things make you feel, food included, and act accordingly.

“If you feel cranky or exhausted and need a nap hours after a sugary breakfast of pancakes and maple syrup, keep that in mind next time you’re choosing your morning meal. Pay attention to your mental health symptoms in response to various foods and use this body intelligence to guide you,” she says.

Food should provide energy, focus and a feeling of nourishment, Naidoo believes. Symptoms such as inflammation, bloating, anxiety, headache and fatigue right after a meal could be red flags that can be addressed with nutritional psychiatry.

Discussing this with a doctor would be ideal, but it’s also important to examine the diet and include healthy whole foods.

Back to basics

Naidoo subscribes to these tenets of nutritional psychiatry:

• Eat whole, be whole – eat lots of vegetables, low-glycemic fruits, nuts, seeds, legumes, whole grains and protein.
• Eat the rainbow – at least 75 per cent of your plate should be whole, fibre-rich, low-glycemic and colourful vegetables such as leafy greens, cucumbers, radishes, aubergine, mushrooms and tomatoes.

• For mental health, folate is the key. This vitamin B complex is required to make normal red blood cells, white blood cells, repair tissues and cells, and synthesise DNA, and is found in leafy greens such as spinach, Swiss chard, collard greens, arugula, cos and dandelion greens. Have four to six cups a day.
• Avoid triggering foods – inflammatory, anxiety-inducing foods such as added and refined sugars, industrial seed oils (soy, corn and grapeseed), processed foods and meats, and high-glucose refined carbohydrates including the “whites” such as white bread, white flour, white pasta and white rice.