By Dr. Mercola

Research shows that the food you eat can have a profound effect on your mental health. So, regardless of your mental health problem, the importance of addressing your diet simply cannot be overstated.

In a very real sense, you have two brains — one in your head, and one in your gut. Both are created from the same tissue during fetal development, and they're connected via your vagus nerve, the tenth cranial nerve that runs from your brain stem to your abdomen.

It is now well established that the vagus nerve is the primary route your gut bacteria use to transmit information to your brain, which helps explain why mental health appears to so intricately connected to your gut microbiome1 — the bacteria and other microbes living in your gut.

For example, researchers recently found that fermented foodshelped curb social anxiety disorder in young adults.2,3 Another study4 found that mice engaged in obsessive-compulsive repetitive behaviors were pacified when given a strain of the bacterium Bacteroides fragilis.

Gut bacteria also produce mood-boosting neurotransmitters like serotonin, dopamine, and gamma-aminobutyric acid (GABA). In fact, the greatest concentration of serotonin is found in your intestines, not your brain.

At the end of the day, if you're trying to address your mental state, optimizing your gut health should be toward the very top of your list.

A number of food ingredients can cause or aggravate depression, but the number one culprit is refined sugar and processed fructose, which feed pathogens in your gut, allowing them to overtake more beneficial bacteria.

Sugar also suppresses the activity of a key growth hormone in your brain called brain-derived neurotrophic factor (BDNF). BDNF levels are critically low in both depression and schizophrenia.

Diets high in sugar also triggers a cascade of chemical reactions in your body that promote chronic inflammation, which over the long term disrupts the normal functioning of your immune system and wreaks havoc on your brain.

Last but not least, refined sugar and processed fructose and grains are key contributors to insulin and leptin resistance, which also plays a significant role in your mental health.

One recent study5,6 found that high-glycemic foods (including those high in refined grains and added sugar) were associated with higher odds of depression.

Added sugar in particular was strongly associated with depression, reconfirming what William Dufty said in his classic best-selling book, Sugar Blues, first published in 1975. Sometimes it takes a while for science to catch up — in this case 40 years!

Other processed food ingredients that can contribute to depression and/or other mental health problems include:

It also causes systemic toxicity, and was recently declared a Class 2A probable human carcinogen. Roundup, in which glyphosate is the active ingredient, has also been shown to increase theantibiotic-resistanceof E. coli and Salmonella.

In fact, a number of studies indicate thatwheat can have a detrimental effect on mood, promoting depression and even more serious mental health problems such as schizophrenia.

Most non-organic wheat is also treated with glyphosate in a pre-harvest processed called desiccation, which adds to its problematic effects (see glyphosate above).

As noted by The Epoch Times:7 "In the last 20 years or so, scientists have developed a new respect for bacteria, and the paradigm is turning from a strategy of war, to one of co-existence. Science now considers a robust, diverse bacterial colony to be essential to good health."

Indeed, the bacteria residing on and in your body outnumber your cells 10 to 1, and viruses in turn outnumber bacteria 10 to 1. In many respects, you are your microbiome.

As Tom Insel, director of the National Institute of Mental Health, told The New York Times:8

Rapidly mounting research reveals that many of these little microbes have very specific functions, and as a whole play a profound role in your biological processes and overall health — including your brain health.

The fact that improving your microbiome can affect your cognitive function means it's also important to nourish your gut to stand a better chance against neurodegenerative disorders such as Alzheimer's. Interestingly, researchers have also found that recurring depressionis associated with shrinkage of the hippocampus, the area of your brain associated with memory formation,10 and depression itself appears to be a risk factor for dementia.

Here, it's important to take your vitamin D levels into account, as both depression and Alzheimer's disease are associated with vitamin D deficiency.

Depressionand anxiety are typically treated with antidepressants, despite the fact studies have shown them to only be on par with placebos in terms of effectiveness. They're also associated with a slew of side effects, including the progression into more severe and/or chronic mental health problems. Recent research may in part explain why antidepressants can worsen the situation rather than making it better.

The 'chemical imbalance' theory states that depression and anxiety disorders are due to low serotonin levels. Selective serotonin reuptake inhibitors (SSRIs) work by making more serotonin available for use in your brain, which is thought to improve your mood. Alas, recent research reveals that people with social anxiety do not have low serotonin; they have higher than normal levels. So further boosting serotonin with an SSRI will only make the anxiety worse...

The new focus on gut health is a welcome departure from the synthetic drug model. As discussed in The New York Times,11 researchers are listing and investigating psychoactive compounds found in feces, and are experimenting with fecal transplants in animals to assess its effect on neurodevelopment:

Researchers have also begun experimenting with fecal transplants in autistic children,12 and while such investigations are still in its infancy, there's plenty of cause for optimism. There does in fact appear to be a close connection between abnormal gut flora in infancy and abnormal brain development — a condition Dr.

Campbell-McBride callsGut and Psychology Syndrome (GAPS). GAPS is the result of poorly developed or imbalanced gut flora and may manifest as a conglomerate of symptoms that can fit the diagnosis of autism, attention deficit hyperactivity disorder (ADHD), attention deficit disorder (ADD) without hyperactivity, dyslexia, dyspraxia, or obsessive-compulsive disorder, just to name a few possibilities.

Total Video Length: 1:13:21

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Dr. Campbell believes autistic children are born with perfectly normal brains and sensory organs, but once their digestive system becomes a major source of toxicity instead of being a source of nourishment, they start to develop autistic symptoms. This theory fits in well with more recent research13 published by the American Society for Microbiology, which identified a bacteria (Sutterella) that is unique to the intestines of children with autism. According to the authors:

All things considered, it seems quite clear that nourishing your gut flora is extremely important to support a positive mood and stable mental health. To do so, I recommend the following strategies:

In summary, foods have an immense impact on both your body and your brain, and eating whole foods as described in my nutrition plan is the best way to support your mental and physical health. Whether you need a quick pick-me-up or you've been struggling with poor mood for a while, the best remedy is likely not found in your medicine cabinet but right in your pantry or refrigerator.

Sources and References

1 The Atlantic June 24, 2015

2 Psychiatry Research April 28, 2015 [Epub ahead of print]

3 Psych Central June 12, 2015

4, 8, 11, 12 New York Times June 23, 2015

5 American Journal of Clinical Nutrition June 24, 2015 DOI: 10.3945

6 Time June 29, 2015

7, 9 Epoch Times July 1, 2015

10 WebMD June 30, 2015

13 MBio January 10, 2012, vol. 3 no. 1 e00261-11