Why do we get stressed?
When we encounter something stressful, our nervous system and adrenal glands send signals to the rest of the body to prepare it for a physical response. The symptoms we experience when we get stressed, such as increased heart rate and heavy breathing, are our body's way of reacting to what it thinks is a threat. Essentially, it is a physiological response designed to ensure our survival.
This hard-wired 'fight, flight or freeze' reaction was necessary millions of years ago when survival meant facing life or death threats. But, in the modern world where these types of real threats to our survival are rarely present, day-to-day things such as work pressure, financial worries, relationship issues, health concerns, and demanding children can trigger the same reactions.
The more exposure we have to these stressors, the more intense and frequent our physiological reactions become until we find ourselves feeling constantly on edge. For those who do not adapt their lifestyles to cope and 'burn off' the effects of their triggered response system, stress can build up and become a health problem.
In this video, Nutritionist Victoria Purdon explores how what we eat can influence our stress levels and the benefits of working with a nutritional professional for stress.
What are the effects of stress?
While it's common to feel stressed every now and then, some people live with chronic (long-term) stress, where they are repeatedly exposed to different stressors for an extended period of time. As the body's stress response system is not designed to be constantly activated, the impact of this on health and well-being can be significant.
If you are feeling stressed, you've likely experienced the following psychological and physical changes.
Effects of stress on the mind:
- mood swings
- becoming withdrawn
- agitation and irritability
- anxious or racing thoughts
- loss of concentration and focus
- feeling tearful
Effects of stress on the body:
- muscle tension
- nausea or dizziness
- increased heart rate or palpitations
- appetite fluctuations
- disturbed sleep or insomnia
- increased blood pressure
These are typically the initial signs that stress is becoming a problem. If it is not effectively managed or treated, it can become chronic. Over time, this can cause serious harm. Long-term illnesses such as depression, diabetes, cardiovascular problems and digestive problems may start to develop, so it's crucial that you seek help as soon as you recognise the signs.
Stress eating: Why do I eat more when I'm stressed?
Stress eating isn't just an emotional response - it can be a physical one, too. While studies have shown that chronic stress can lead to emotional eating (particularly amongst women), it can also have a physical effect on how much you eat. Your body releases cortisol (often referred to as the stress hormone, it prepares us for fight or flight by providing more energy to your body, allowing you to remain on high alert) to protect itself during a stressful event.
When your cortisol levels are elevated over a long period of time (such as when you experience repeated or constant stress), this can lead to eating more, your body storing more fat, and weight gain. While your body's cortisol levels fall naturally after a period of stress, if you are constantly stuck in a stress state, your cortisol levels may stay elevated, meaning you might eat more.
Finding ways to reduce your stress levels, eating foods to relieve stress, avoiding foods that can increase stress, and working with a nutritional professional can all help you develop healthier habits and avoid stress eating.
Stress and digestion
The effects of stress on our eating habits and digestion can be significant, leading to appetite fluctuations and digestive problems like irritable bowel syndrome (IBS).
This is because the activated fight or flight response in the central nervous system immediately slows down digestion. This restricts blood flow, slowing the contractions of the digestive muscles and decreasing secretions needed for digestion. This is so that the body can prioritise more important functions, such as heart and breathing rate, in order to prepare the body to attack or escape from a perceived threat.
After a stressful period, the human body can go into 'recovery mode' where appetite is increased and food cravings take hold. At the same time, metabolic rates will drop to conserve energy, which means the body is more likely to store fat, particularly around the abdomen. Feeling stressed also leads to an increase in levels of cortisol, which is a hormone that, if out of balance, can contribute to weight gain.
Alternatively, chronic stress can suppress appetite, which can lead to weight loss. This may also be linked to nervous movements such as pacing, tics and leg shaking. While some people completely shut down when they are feeling stressed, others unintentionally move more.
Stress and the gut microbiome
Chronic stress can impact both the composition and function of your gut microbiome, which, in some cases, can lead to an imbalance (dysbiosis) where there may be a lack of beneficial bacteria, too much potentially harmful bacteria, or less microbial diversity. This imbalance can be caused by a number of different factors other than stress, including diet, infections, and certain medications. Dysbiosis can cause different issues, including digestive problems, inflammation, metabolic disorders, and a weakened immune system.
Stress and diet
Research strongly indicates a link between stress and diet. Research into diet, stress and mental health (the relationship between diet, stress, obesity and psychiatric disorders) reveals that diet and obesity can directly affect our moods, while stress can lead to changes in diet habits, which can then affect weight. Research highlighted that specific parts of our diet can lead not only to changes in mood but also stimulate inflammation.
It's possible that someone eating a healthy, balanced diet is going to be far less stressed than someone eating a poor diet. If you're feeling overly stressed, your digestive system is probably under a great deal of strain - making changes to your diet could be key to feeling better physically and emotionally.
Which foods have a negative effect on the body when we're stressed?
There are many different foods which can negatively affect your body when you are stressed. Below, we share an overview of certain foods to avoid, which may help improve symptoms of stress.
Caffeine
A chemical found mostly in tea, coffee and some soft drinks, caffeine reduces our ability to deal with stress. This is because it acts as a stimulant, causing the adrenal glands to release more hormones like cortisol (which are already high due to the strain our bodies are under). High levels of caffeine also contribute to insomnia and nervousness, which are intrinsically linked to stress.
Caffeine consumption can also deplete levels of magnesium (needed for energy production) and metabolism-boosting B vitamins from the body. Substituting coffees and teas for herbal varieties can help reduce your caffeine consumption, and it helps to be mindful of caffeine content in foods such as chocolate.
It is worth noting that caffeine doesn’t affect everyone in the same way. Our genetics also play a significant role in how we metabolise caffeine, as well as how sensitive and tolerant we are to it. It’s why some people don’t feel the effects of caffeine as much (or at all).
Foods high in fat and sugar
Cravings for processed and sugary foods may be heightened when you are feeling stressed, but it is important to avoid consuming these in high quantities. Not only can they be detrimental to your overall health, but they can also make you feel worse in the long term. Sugar, for example, will provide a short burst of energy and temporary relief from stressful feelings, but this will be swiftly followed by a 'low' period when your blood sugar levels crash. This can lead to irritability and increased food cravings, which can put a strain on the body.
According to a 2017 study into the relationship between fatty acids and different depression related brain regions, saturated fats (like those found in butter, fatty meats, or fried food) have been linked to feeling more depressed. A 2023 study also found links between ultra-processed food (UPF) and the risk of depression, with those who were in the top fifth of consumers for UPFs being at a 50% higher risk of developing depression than those in the bottom fifth.
Alcohol
Many people turn to alcohol as a means of dealing with stress. While it may have an instant calming effect on the body, in the long term, alcohol may lead to an increase in stress in people’s lives as it can worsen stress and anxiety through disrupting brain function, negatively impacting sleep, and making it harder to cope with stressful situations.
Drinking heavily can lead to complications such as addiction and can take a toll on overall health and well-being. Sleep problems, nervousness, and skin irritations are common side effects of drinking because alcohol makes the body release larger amounts of adrenaline and affects blood sugar levels.
If you know you have a particularly stressful time coming up, then plan for it. Make use of healthy ready meals with chopped and frozen vegetables. One of my favourite meals is ready cooked salmon steak with green salad leaves, a drizzle of olive oil and some oatcakes or brown rice.
Which stress-relieving foods should I eat more of?
Chronic stress can weaken the immune system and affect the body's defences, leaving a person more susceptible to infection and disease. If a stressed person becomes ill, this will put the body under more strain. You can try to incorporate more of the following foods into your diet.
Fruit and vegetables
Eating a diet rich in fresh fruit and vegetables will ensure you get plenty of nutrients and minerals, which is crucial when your body is feeling stressed and using more nutrients than it would normally. Aim to eat at least five portions of fruit and vegetables a day to get a sufficient amount of vitamins and minerals, and focus on foods containing vitamins B, C and magnesium.
- B vitamins - Found in bananas, leafy greens, nuts, seeds, meat, fish and dairy products, these provide the body with energy after a period of stress.
- Vitamin C - The largest store of vitamin C lies in the adrenal glands, which are responsible for the production of stress hormones. Keep these healthy by eating plenty of vitamin C-rich foods such as oranges, tomatoes, peppers, leafy greens and broccoli.
- Magnesium - This mineral can help to relax muscles and reduce anxiety while also playing an essential role in hormone and energy production. Nuts - particularly Brazil nuts - are high in magnesium, as are beans and lentils, whole grains and leafy greens.
Complex carbohydrates
Eating whole, unprocessed carbohydrates such as wholegrain bread, pasta and cereals, as well as oats and brown rice, will help to enhance levels of serotonin - the mood-boosting hormone that helps you to feel happy and more relaxed. Low levels of serotonin in the body are linked to anxiety and depression, as well as poor quality sleep; so keeping this hormone in balance is key for dealing with stress. In addition, complex carbohydrates are digested more slowly than refined, processed varieties, which can help stabilise blood sugars.
Essential fatty acids (EFAs)
Essential fatty acids (Omega 3 and 6) are vital nutrients which help the body to function effectively, particularly the brain. EFAs also help to moderate the effects of psychological and physical stress. This is because they lower the release of glucocorticoids (hormones released from the adrenal gland) under stressful conditions. To get the right balance of EFAs in your diet, eat sources such as oily fish, nuts and seeds.
Calcium-rich foods
Research into stress and diet shows that calcium may be able to help reduce certain symptoms, such as muscle tension and anxiety. Therefore, including plenty of calcium-rich foods in your diet (such as low-fat milk, yoghurt, sesame seeds, kelp, cheese, leafy greens and broccoli) may be beneficial. Eating these in the latter part of the day is thought to help with absorption.
The benefits of a Mediterranean diet
Research suggests that the Mediterranean diet could be associated with decreased feelings of stress and mental distress. Rich in vegetables, whole grains, and heart-healthy fats like fish, nuts, and olive oil, eating a more Mediterranean diet could help improve heart health, cognitive functioning, and blood sugar, while playing a key role in dealing with stress and improving mood.
Fermented foods
Fermented foods may help manage feelings of stress and anxiety. Rich in probiotics, fermented foods can positively influence gut health, potentially improving mood. Probiotics (beneficial bacteria) can help improve gut health and, according to some research, may have a positive impact on mood and anxiety thanks to how it influences the gut-brain axis, which connects the gut microbiome to the brain.
Healthy snacks
Eating healthy snacks throughout the day, such as fruit, raw vegetables, yoghurt, nuts, and seeds, will keep your blood sugar levels stable and your metabolism functioning smoothly. On stressful days, it is important to eat little and often to minimise peaks and drops in energy levels, and this includes eating a nutritious, filling breakfast in the morning. For some people, stress can make them skip or forget to eat their meals, and this increases the likelihood that they will reach for processed or sugary foods when they are hungry.
How can a nutritionist help with stress and diet?
Seeing a nutritional professional can be helpful if you want to make long-term positive changes to your diet and manage stress. A nutritionist will provide tailored nutritional advice and support to ensure all your needs are catered for and your specific goals are met. This will involve an assessment to pinpoint your nutritional needs and what stress-relieving foods will be the most beneficial for you.
As part of your assessment, you will look at triggers and contributing factors, as well as any underlying imbalances such as adrenal hormones and thyroid problems. Following this, you will likely be given a specific eating plan to follow, which may also outline lifestyle changes such as physical activity, which will play an important role in stress management in the long term.
A nutritional therapist will look at all aspects of your diet and lifestyle and can help with the way forward. They will work out what is causing your body to be stressed.
A nutritionist may also be able to help introduce you to more mindful eating habits. Mindful eating can not only help promote a more conscious, positive relationship with food as it teaches you to focus on your hunger and fullness cues, but it can also help with unhelpful habits such as emotional eating, which can be triggered by stress.
