How Food Impacts Stress and Anxiety

By Dr. Lanae Mullane, ND

It is important to note that while dietary changes alone cannot cure anxiety, changes in our dietary patterns and the foods we eat can help reduce symptoms, increase energy, and support our ability to better adapt to stress. The stress response is a normal adaptive coping mechanism that humans have relied on for millions of years for protection (e.g. running from a bear in the wild). The stress response was designed to resolve quickly. Unfortunately, in our modern society, daily life events can lead to chronic, or continuous, mild stress exposures. Our physiological stress response--higher heart rate, shallow and rapid breathing, increased release of adrenaline, noradrenaline, and cortisol--occurs whether you are running from a bear or sitting in morning rush hour. As complex as the body is, it isn’t able to identify the difference. Prolonged exposure to chronic stress can disrupt your digestive health by staying in the sympathetic “flight, fight, or freeze” state versus the parasympathetic “rest and digest” state that allows us to properly digest and absorb nutrients from the foods we eat.

Why is food an important topic when discussing anxiety and stress? It has to do with the gut-brain axis. The gut is sometimes referred to as the second brain. It is also referred to as the enteric nervous system (ENS) and consists of millions of nerve cells lining the gastrointestinal tract from mouth to rectum. The brain has direct effects on the digestive tract, including the stomach and intestines. Just the thought of eating food can release digestive enzymes in saliva, the stomach, and the pancreas before you even place a bite of food in your mouth. Issues in the gut can send signals to the brain, just as issues in the brain can signal to the digestive tract; the gut and the brain are closely connected. This can lead to a “chicken or the egg” situation: Are digestive issues the cause or the result of stress and anxiety? In addition, the lining of the digestive tract also contains a majority of your body’s serotonin receptors. Serotonin is a neurotransmitter needed for nerve cells and brain function and also plays a critical role in mood and cognition.

Consuming a nutrient-dense, whole-foods diet contributes to lowering anxiety by providing vitamins, minerals, amino acids, and omega fatty acids. A well balanced diet also stabilizes blood sugar, supporting numerous physiological and biochemical pathways that help our body adapt to the demands of stress and anxiety.

Is there a certain meal plan someone with stress/anxiety can follow?

I recommend starting with small changes. We do not want to increase anxiety and stress with major shifts in our diet. I tell my patients to focus on adding healthy foods to their diet versus providing a long list of foods to avoid. When we increase our consumption of healthy foods, unhealthy foods start to find less room on the plate. This can also alleviate any feelings of stress or anxiety if we consume a food that we are told not to eat.

Start by increasing your intake of vegetables (especially dark leafy greens) by having 1-2 servings with each meal. Once you have that down, start incorporating higher omega 3 fish, healthy fats (e.g. avocado, almonds, walnuts, chia and pumpkin seeds), dark berries (e.g. blueberries, raspberries, and blackberries), and lean animal- or plant-based proteins.

The Mediterranean Diet has not only been associated with lower cardiovascular risk, but research has shown positive results in reducing depressive and anxiety-related symptoms. The Mediterranean Diet is based on the eating habits of traditional cuisine of countries bordering the Mediterranean Sea and consists of higher intake of vegetables, fruits, whole grains, beans, nuts, seeds, and olive oil. The diet recommends choosing poultry and fish over less lean protein sources, like red meat. Healthy fats over saturated and trans fats is also a foundation of this diet.

The Gut-and-Psychology Syndrome (GAPS) Diet addresses the gut-brain connection utilizing a dietary plan derived from the Specific Carbohydrate diet. This dietary plan was created to address those suffering from intestinal and neurological conditions due to an imbalance of the microbiota within the digestive tract. GAPS aims to remove foods that can be challenging on the body to digest and may cause disruption to the gut bacteria, and replace them with nutrient-dense food options to support a healthy intestinal permeability. This diet can be challenging, so I recommend getting support with the protocol from your doctor or nutritionist.

Are there foods that can lead to an INCREASE in stress or anxiety?

Caffeine can trigger our sympathetic “flight, fight, or freeze” response, leading to an increase in epinephrine, also known as adrenaline. This is the same autonomic nervous system response that our body has when we perceive a situation as worrisome or dangerous. Caffeine can cause an increase in heart rate, disruption in sleep, digestive disturbance, irritability and agitation. All of these can increase one’s level of perceived stress and anxiety. Genetics may also play a role in how well your body handles caffeine. Variations in the CYP1A2 gene can determine if you are a fast or slow metabolizer of caffeine. Slow metabolizers take longer for their bodies to process caffeine, contributing to possible negative effects of caffeine like insomnia and anxiety. Although the FDA considers 400 mg of caffeine (~3-4 cups of coffee) per day to be safe, I recommend limiting caffeine intake to no more than 2 cups of coffee per day and to drink those cups before 12 pm in the afternoon.

Alcohol is often used to help people unwind from a long day, celebrate the end of a work day at happy hour alongside fellow colleagues, or to mitigate stressful life situations due to its sedative-like effects that can cause a sense of relaxation. Although alcohol may reduce anxiety temporarily, it also has the possibility of increasing anxiety within a few hours after consumption that can last into the following day. After the euphoric effects of alcohol fade, the levels of the neurotransmitter serotonin also decreases. This can lead to feelings of anxiousness and depression. Alcohol can also disrupt blood-sugar levels and cause dehydration, both of which can lead to heart palpitations, weakness, dizziness, and fatigue. If you are going to drink, remember to drink in moderation, don’t drink on an empty stomach, and consume a glass of water in between each alcoholic beverage.

Indulging in sugary comfort foods--whether to cope with painful emotions or stress--has been shown to temporarily reduce activity of our stress response through the hypothalamic-pituitary-adrenal (HPA) axis. The temporary alleviation of stress can lead to perpetuating emotional eating habits. Consuming sugary foods can also lead to a spike and quick drop in blood sugar that can cause uneasiness, changes in mood, and feelings similar to a panic attack. This can turn into a cycle of gravitating to something sweet every time you need a boost in mood or energy, leading to a rollercoaster of highs and lows that can contribute to anxiety.

Are there foods that can help DECREASE in stress or anxiety?

Consuming fruits and vegetables has been shown to support a healthy mind and body, yet according to the CDC, in 2017 only 1 in 10 adults met the federal fruit or vegetable recommendations. Here are just a few examples of vegetables and fruits with mood-supporting properties:

● Dark leafy greens (e.g. kale, spinach, beet greens, Swiss chard) are abundant sources of magnesium, a mineral that increases GABA, which encourages relaxation.

● Asparagus is a rich source of fiber, potassium, and folate. In 2013, the Chinese government classified asparagus as a natural functional food for its anxiolytic, or anxiety-lowering, properties.

● Fermented sauerkraut is a probiotic that creates healthy bacteria to inoculate your digestive tract, supporting the gut-brain connection.

● Broccoli contains zinc, vitamin B6, and vitamin C which can help balance the stress hormone cortisol.

● Berries (e.g. Blueberries, strawberries, blackberries, and raspberries) contain bioactive antioxidant compounds such as polyphenols, flavonoids, and anthocyanins. Berries are considered a “functional” food as they carry beneficial effects in physiological processes that support heart, cognitive, and mood health.

● Avocado contains magnesium and B vitamins that are important in a host of biochemical reactions associated with healthy nervous system function.

● Cherries contain the antioxidant quercetin that may help with physiologic effects of stress like reducing oxidative damage and lowering inflammation.

● High Vitamin C fruits (e.g. oranges, papaya, lemons, pineapple): This water soluble vitamin is not only good for immune health but may also help reduce the physical and psychological effects of stress.

When choosing your protein source, try to look for grass-fed, grass-finished, organic, sustainable, and wild caught options when possible. This helps reduce toxic environmental exposures and provides more nutrient dense sources of vitamins, minerals, and omega 3s.

● Omega 3 fatty acids: Omega 3s can travel through the brain cell membrane and are important for nervous tissue and brain health. When picking fish, go for higher omega 3, lower mercury containing fish. Think of the acronym SMASH (Salmon, Mackerel, Anchovies, Sardines, and Herring).

● Oysters are loaded with the trace essential mineral zinc. Zinc is necessary to make and maintain the balance of neurotransmitters like serotonin, dopamine, GABA, and norepinephrine--these are all important for mood, sleep, and stress response.

● Turkey is high in tyrosine, an amino acid that helps make dopamine, epinephrine and norepinephrine, benefiting mood and brain health. You can also get tyrosine in tofu, seaweed, eggs, fish, and chicken.

● Quinoa is a complete plant-based protein, containing all nine essential amino acids that our body can’t make. This seed is a complex carbohydrate that helps keep your blood sugar levels steady, preventing spikes and dips in energy. Complex carbs consist of higher dietary fiber that can be absorbed and fermented by the intestinal bacteria into short chain fatty acids that contain neuroprotective properties.

Make sure to drink enough water throughout the day. Dehydration can cause an internal physiologic stress on the body and lead to a decrease in energy, and possible increases in constipation, headaches, rapid heart rate, and irritability. Staying hydrated can help improve your mood and decrease stress.