If you had a doughnut and coffee for breakfast, you probably wouldn’t be that surprised if you felt sluggish and even a little blue afterward. Had you started your day with, say, eggs and whole-grain toast or a veggie- and fruit-packed smoothie, you’d expect to feel much better.

While most of us know from our own experience how our diet affects our moods and energy levels, scientific evidence now shows just how crucial food is as “brain fuel.”

Latest development: For the first time, high-quality scientific research has confirmed that dietary changes can dramatically improve depression. In fact, diet plays such a fundamental role in mental health that nutritional psychiatry is increasingly being incorporated into evidence-based mental-health practices to help prevent and treat depression and anxiety and even guard against dementia.

To learn more about this important new approach, Bottom Line Health spoke with Drew Ramsey, MD, a psychiatrist and leading proponent of the use of dietary changes to improve brain health.

How do the foods we eat affect our brains? Let’s begin with the idea that all the molecules in your brain start at the end of your fork. For example, for your brain to produce serotonin, a brain chemical that regulates moods (and sex drive) along with weight, you must consume tryptophan, an amino acid found in higher amounts in some foods such as pumpkin seeds, asparagus, fish and meats.

Other nutrients, such as zinc and omega-3 fatty acids, are key building blocks of the brain and affect neurogenesis (the creation of new brain cells)…levels of brain-derived neurotrophic factor (a hormone that you need to stave off depression)…and chronic inflammation, which is also linked to depression.

Do foods make a big difference or just a little? There isn’t a single “superfood” for treating depression or other mood disorders. But dietary changes—eating more plant foods and seafood and cutting out fast food and simple sugars—clearly help, whether they’re used alone or in combination with antidepressants or talk therapy.

Haven’t we known for a while that nutrition plays a role in brain health? Many studies have suggested that nutritional changes can help patients with mood problems, but there’s never been conclusive proof. That changed with the SMILES (Supporting the Modification of Lifestyle Intervention in Lowered Emotional States) trial, which was published in early 2017 in the journal BMC Medicine.

It was the first-ever randomized, controlled clinical study to investigate dietary interventions for treating clinical depression. The study looked at 67 men and women with moderate-to-severe depression, most of whom were taking an antidepressant or receiving regular psychotherapy. Half were put on a Mediterranean-style diet for 12 weeks…the other half continued to follow their usual (and largely unhealthy) diets.

After three months, nearly one-third of those who made dietary changes had improved so much that they no longer met the clinical criteria for clinical depression. In other words, they had full remissions. Those who hadn’t improved their diets had only an 8% remission rate.

Can nutrition help with dementia? A healthy diet can help prevent vascular causes of dementia, such as stroke. There’s also good evidence that many of the plant-based molecules such as lycopene (found in tomatoes and other red fruits and vegetables) and flavonols (found in onions, wine, chocolate and many other healthy foods) can produce brain changes that reduce the risk for different forms of dementia, including Alzheimer’s disease.

What foods do you usually recommend? I focus on overall dietary patterns and categories of brain healthy foods (such as seafood, leafy greens and colorful “rainbow” vegetables)…complex carbohydrates (such as whole grains)…grass-fed meat and dairy…and free-range poultry and eggs.

Important: Seafood is a crucial food category that’s missing from most Americans’ diets. I advise everyone to eat more salmon, bivalves (such as oysters and mussels), anchovies and other types of seafood.

What about supplements? Several clinical trials have shown that specific supplements—fish oil, zinc, B vitamins, etc.—might be helpful for alleviating depression and other mood problems. Supplements are convenient if you don’t eat seafood (a main source of omega-3s), follow a restrictive diet (vegans need to take vitamin B-12) or have a deficiency in need of rapid correction. I tend to emphasize food because no one sits down to a fine meal of vitamins and supplement shakes!


To rule out medical causes of depression, including thyroid disorders, and to check levels of certain nutrients (such as vitamin D and vitamin B-12), psychiatrists routinely order blood tests. A nutritional psychiatry assessment can also be conducted to understand what patients are eating…when they eat…what their favorite snacks are…and so on.

While physicians typically haven’t learned much about nutrition in medical school beyond basic biochemistry, this is changing! A culinary medicine curriculum developed by Tulane Medical School is being adopted by 28 medical schools around the country. And the American Psychiatric Association has recently offered the Brain Food Workshop, developed by researchers at Columbia University, at its professional meetings.

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