How are you?

After all the difficulties of the last year or so many of us are feeling a little low. Some reports suggest that 1 in 5 adults now suffer from moderate to severe depression, a number that has doubled since March 2020.

While much is out of our control, we can look at our diets. Diets influence mental health in a negative or positive way, let’s look at how some of the ways we eat can impact our mood.

Not eating enough nutrients

Nutrient deficiencies will impact our mental health. For example B Vitamins are not only needed for energy production but are also vital for the normal function of the brain, nervous system and psychological function. Include plenty of high B vitamin foods such as green leafy vegetables, eggs, salmon and legumes. B Vitamins are often lost from vegetables during cooking, to help avoid this, steam or sauté vegetables or if you do boil them keep the water and use for gravy or soups. Unfortunately, they are easily destroyed by alcohol too so if you are a heavy drinker you are more likely to be deficient.

• Magnesium is needed for the normal nervous system and psychological function, a lack of magnesium is often associated with feelings of low energy and fatigue. A diet high in dark leafy greens, seeds, beans, fish, whole grains, nuts, dark chocolate, yogurt and avocados will help top up your magnesium levels.
• Vitamin D Who doesn’t feel better after a little sun? Vitamin D is the only vitamin our skin can manufacture from the sun’s rays and low levels of vitamin D are associated with low mood. Since it is difficult to obtain from food it is no surprise the British often test for low levels. You only need 20 minutes of daily sun skin exposure to obtain enough vitamin D However take care not to burn, especially if you have fair skin. During the winter months the NHS recommends everyone takes a vitamin D supplement to avoid deficiencies.
• The omega 3 essential fatty acid DHA, found in oily fish is needed for normal brain function. Recent research shows a lack of omega 3 fats is common, if you are not eating oily fish 2-3 times weekly (e.g. sardines, mackerel or salmon) you may wish to consider a supplement. Studies giving supplemental marine omega-3s have shown promise for improving numerous mental health conditions such as depression ADHD and autism.

Fish also contains all essential amino acids, many of which are helpful for mood regulation. Examples include tryptophan, a precursor to the hormones melatonin and serotonin which help regulate our body clocks sleep/wake cycle. Serotonin is known as our ‘happy’ hormone. Other foods high in tryptophan include turkey, chicken, celery, cottage cheese, avocado, and banana.

Another useful amino acid is tyrosine. Tyrosine can be converted into the neurotransmitter dopamine. Dopamine acts as a messenger to the brain and is released during pleasurable activities. Symptoms of low levels of dopamine include depression, lack of motivation or concentration and memory issues. Foods high in tyrosine include almonds, bananas, turkey, seeds and yogurt.

The calming amino acid theanine also increases brain chemicals such as serotonin, dopamine and gamma aminobutyric acid (GABA). Low levels of GABA lead to increased anxiety and difficulty to relax. Theanine is found in tea, primarily in green tea and some mushrooms.

Not eating enough…ever felt ‘hangry’?!

Have you noticed when you’re hungry you feel more irritable? The term ‘hangry’ has been used a lot recently and there is some evidence to support it. A drop in blood sugar (hypoglycaemia) is a strong physiological and psychological stressor. When our blood sugar drops the hormones cortisol and adrenaline are released in an attempt to re-establish normal blood sugar levels. But those hormones also happen to lead to irritability. It’s not just anger either, studies on rats have shown that low blood sugar causes decreased mood, depression and stress.

People on extreme diets, or who regularly miss meals, may find themselves in a vicious cycle as a drop in mood may leave someone not wanting to eat and not eating leads to a drop in mood. To help keep blood sugar levels stable eat regularly, make sure all meals are balanced with proteins, complex carbohydrates and fats and avoid sugary snacks.

High processed / refined carbohydrate diet. Gut bacteria

Over the last few years our understanding of the gut mind connection has increased greatly. Essentially if our gut microbiome, the vast community of bacteria and fungi that inhabit every nook and cranny of our gastrointestinal tract, is unhappy the likelihood is we won’t be either. Studies have shown that patients with depression, and other mood and anxiety disorders, show distinct compositional changes in their gut bacteria profile.

We have known for a long time that our gut bacteria is destroyed by medications such as antibiotics however we are now discovering that a diet high in processed food also has a major impact. A 2018 study found that following a diet of processed foods for just 10 days reduces gut bacteria diversity by 40 percent. However our gut does recover when we change to a balanced healthy diet, include a wide variety of whole foods and foods that naturally contain live bacteria (probiotics) include yogurt, cottage cheese, sauerkraut, miso soup and fermented pickles.

If you are struggling to eat or prepare healthy meals, get back to basics with easy to prepare soups and salads. Eggs with wholemeal toast is better than nothing if you are feeling overwhelmed. Keep hydrated and if your feel very low or have been suffering for a while, talk to your doctor.

References:

Mary I Butler  et al (2019) From isoniazid to psychobiotics: the gut microbiome as a new antidepressant target Br J Hosp Med (Lond) 2;80(3):139-145. doi: 10.12968/hmed.2019.80.3.139.

Dena Schmidt (2018) Stunning study: Processed foods destroy gut bacteria and diversity, leading to tragic result. https://www.naturalhealth365.com/processed-foods-probiotics-2636.html

James J DiNicolantonio and   James H O'Keefe 2020  The Importance of Marine Omega-3s for Brain Development and the Prevention and Treatment of Behavior, Mood, and Other Brain Disorders Nutrients 4;12(8):2333. doi: 10.3390/nu12082333.