Stress - How a PBD Can Help Reduce Anxiety
Can a whole food plant based diet help reduce anxiety symptoms?
On the surface of it, a diet that is rich in micronutrients like zinc and magnesium (i.e. plant based) provide the key nutrients needed to synthesize the happy neurotransmitters in our gut and brain and can help to feel calmer.
But it goes deeper than that.
We all know that anxiety can cause butterflies in our stomach. Just think back to the last time you had to give a speech or performance in front of hundreds.
But did you know that our gut can also send signals to our brain and affect how we feel?
We now know that the gut and the brain communicate with each other constantly, and that the communication is a two-way system via the vagus nerve and a myriad of neurotransmitters. Traditionally, doctors have thought of anxiety or depression as a ‘brain disorder’ and that it is caused by an imbalance of neurotransmitters like serotonin in the brain. But more and more doctors are now talking about anxiety and depression as a symptom of inflammation in the body. And in particular, inflammation in the gut can play an important role in anxiety and depression. More research is needed but it has been suggested from current studies that if the gut is inflamed or injured, alarm signals may be sent to the brain and this can bring about symptoms of anxiety or depression.
How does gut health and what you eat affect your mood and mental health though?
Serotonin is our happy hormone – we need the right amount of serotonin in our brain for optimal mental health. When serotonin level is low, it can cause depression and anxiety symptoms. Indeed, most anti-depressants and anxiety medication work on mechanisms in the body to increase the serotonin level in our brain.
Research has shown that 70%-80% of our serotonin is made in the gut. So good gut health provides the foundation to good mental health. Our gut contains trillions of microbes (aka the gut microbiome) which helps maintain healthy gut function. The microbiome also plays a role in regulating serotonin production, and can be disrupted by many factors, the main ones being our diet and environmental toxins. 
A diet high in processed foods, sugar, saturated fat and pesticides/hormones (highest concentration found in conventionally farmed animal products) can alter a healthy microbiome. In addition, a diet that is low in fiber will starve the cells lining our gut and lead to poor gut function - because fiber is food for these gut bacteria.
A whole food plant based diet is high in fiber, which feeds the good gut bacteria that then makes short chain fatty acids like butyrate. Not only is butyrate an essential fuel for our gut cells, it also helps modulate satiety, keeps the microbiome in check, and may have anti-inflammatory effects. Speaking of inflammation, the other reason why a whole food plant based diet may help to reduce anxiety symptoms is because of the absence of animal proteins which can be inflammatory.
Animal proteins can cause inflammation in the body via a few mechanisms:
1) Animal products, especially that which comes from conventional farming methods, are high in arachidonic acid and in excess, this pathway can drive the inflammatory process in the body.
2) Animal products are a major source of environmental toxins like pesticides, PCB, Dioxins, heavy metals because these substances are present in the animal feed, and bio-accumulate in the animal over their lifetime and become concentrated, particularly in the fat and soft tissues. This can then cause a disruption to the gut barrier function and also drive inflammation in the body.
3) Delayed food allergy. This is different to an immediate allergy which often visible and acute. A delayed food allergy is usually insidious and comes on slowly, up to 72 hours after ingestion, so it can be difficult to make a connection particularly since symptoms may be totally unrelated to the gut e.g. migraines, rash, anxiety. Dairy and eggs are among the top food allergens, along with nuts, seafood, soy and wheat.
And if we think of inflammation as an underlying contributing factors to anxiety, then a whole food plant based diet that is rich in antioxidants will help to reduce the inflammation in our body.
So if you are feeling low or anxious, make sure you seek medical help and follow your doctors’ medical advice. At the same time, perhaps start looking at your diet and see whether you can make any changes to incorporate more plant foods which will feed your gut microbiome, provide phytonutrients to nourish your body and reduce inflammation.
Gut microbes promote colonic serotonin production through an effect of short-chain fatty acids on enterochromaffin cells.
Reigstad CS, Salmonson CE, Rainey JF 3rd, Szurszewski JH, Linden DR, Sonnenburg JL, Farrugia G, Kashyap PC FASEB J. 2015 Apr; 29(4):1395-403
Meet Our Guest Writer…
Dr. Vivian Chen
Dr Chen is a UK medical doctor who lives in California, USA (UK board certified in internal medicine and family practice, MBBS, MRCP, MRCGP) - and also holds UK postgraduate certifications in diabetes care and skin surgery. She became interested in integrative medicine when herself and her family had health issues that allopathic medicine could not treat. She decided to get educated on using food as medicine, and became certified as an Integrative Health Practitioner, and now work with her clients to get to the root cause of health issues by use lifestyle measures to help them reach their health goals.