Episode 28: Food and mood

OnCore Nutrition - Two Peas in a Podcast

Beyond Blue - 1 in 7 Australians will experience depression in their lifetime and 1 in 4 will experience anxiety.

Mood disorders are something we can’t ignore.

One area that’s gained a lot of traction is the way food, dietary patterns, dietary quality and lifestyle are having a profound impact on our mood and mental health.

Usually pharmacotherapy (medication) and psychotherapy are used as firstline treatment of depression, however remission can often be challenging to achieve.This has prompted the need for further strategies in relation to diet and lifestyle in the treatment of depression. What we eat can have an impact on our brain chemistry and brain health.

Whilst there is no single food that can help improve depression, we are discovering that what and how we eat as a whole can have an impact.

We often consider the brain for it’s psychology and forget it’s biology. The brain is an organ. Incredibly complex one. We need to care for it like we do any other organ. A heart that is not cared for will show signs of damage eg arrhythmias, blood pressure issues, poor exercise tolerance A brain that is not cared for will also show symptoms. The trouble is these symptoms are those related to brain function - mood, personality, decision making and processing and memory. These are biological symptoms of a biological organ. It’s not just psychology. Often these type of symptoms are brushed off. They’re easier to ignore than palpitations or tightness in the chest or wheezy breathing. The reality is that our brain cells are made up of essential fatty acids that we can only get from our diet. Our neurotransmitters require essential nutrients that you can only get from your diet We can look after our brains and take a preventative nutrition and lifestyle approach just as we would look after our heart and lungs

Lancet commission 2017

https://www.thelancet.com/commissions/dementia2017

Food, hormones and neurotransmitters

• Carbohydrates - when we eat CHO’s this triggers a release of insulin to help transport the CHO’s into the cells to be used as energy. This insulin trigger also stimulates the release of tryptophan, which is an AA which is a precursor for serotonin (which is associated with improved mood and feeling happy). Low GI carbs are seen to be the most beneficial whereas high GI carbs will give an immediate but temporary effect in regard to serotinin release.
• Protein - There are specific amino acids can affect our brain health as a number of neurotransmitters are made up of AA’s.In particular the neurotransmitter (messenger) dopamine is produced from the AA tyrosine and as mentioned above serotonin is made from the tryptophan. A lack of these particular AA’s, will result in downregulation of these neurotransmitters, which can precipitate lowered mood.
  • There is a condition called phenylketonuria the buildup of AA can also result in brain damage and mental retardation. e.g the excessive buildup of phenylalanine can cause brain damage and mental retardation.
• Omega-3 fatty acids - The brain is one of our organs that contains the most amount of fat in the body (~60% fat). There have been studies which support that sufficient intake of long chain PUFAs (particularly DHA), may reduce the risk of depression. DHA is also essential for brain growth and development in children.
• Vitamins
  • B12 - may be beneficial in the context of reducing dementia risk and assist with cognitive function in older adults. Sources include: beef, liver, chicken, fish, shellfish, dairy, eggs
  • Folate - Researchers have found links between folate deficiency and depression. Still unclear if the poor nutrition, relating to the depression, causes the folate deficiency or the folate deficiency results in depressive symptoms. Sources include leafy greens (spinach, broccoli, peas, lentils, legumes)
  • Vit D - ensuring levels are therapeutic has been found to have a positive benefit in the context of depression. In cold/dark countries where Vit D deficiency is more prevalent, as can be depression. Sources include eggs, oily fish and sunshine!
• Minerals:
  • Iron - Important in supplying oxygen to our brain and for the production of neurotransmitters and myelin (lipid rich layer/sheath that surrounds our nerves). Sources include red meat, fish, legumes, green leafys
  • Lithium - well known in the mental health field and is present in many medications used for depression, bipolar, etc...
  • Iodine - through the thyroid hormone supports energy metabolism in the cells of our brain. Iodine is particularly important during pregnancy as deficiency may result in cerebral dysfunction.
  • Zinc - antioxidant which can protect brain cells and can also improve the uptake of antidepressant medication, sources include: meat, poultry, legumes, pulses, nuts, seeds

Dietary patterns:

• SMILES trial (undertaken locally in Melbourne & Victoria)- An interventional study which used dietary improvements as a treatment modality for patients with pre-existing depression. The dietary intervention group received 7 sessions with a clinical dietitian for personalised nutrition advice and counselling. Also followed a modified med type diet.The control group received an interesting intervention known as ‘befriending’ or ‘social support’ which included trained professionals discussing topics of interest e.g. such news, music or sport. For subjects who were difficult to engage, cards or board games, were used as a tool to keep them engaged. The results found that participants in the dietary intervention group had a greater reduction in depressive symptoms over the 12 week period ( in comparison to the social support group). At the end of the trial, ~33% of the subjects in the dietary support group were considered in remission of their depression, in comparison to 8% in the social support group.
• Another interesting point was that there wasn't a change in weight or BMI - dietary quality may be more valuable than weight loss.
• Economic evaluation - cost saving in using this treatment approach
• In summary those who made the greatest change to their diet saw the greatest benefit in regard to their depression
• This also highlights that we need improved pathways and access to dietetic care in the treatment of depression.
  
• Depression in children and adolescents is hugely important because the average age of onset of anxiety and depression is in this group
• Relationship Between Diet and Mental Health in Children and Adolescents: A Systematic Review - Showed a relationship between diet which was high in foods containing refined CHO’s, saturated fat and processed foods, and poorer mental health in both children and adolescents. We know the onset of anxiety and depression is coming up at a much younger age, therefore early intervention strategies such as improving dietary quality and a population level may be beneficial.
  
• The impact of whole-of-diet interventions on depression and anxiety: a systematic review of randomised controlled trials - This paper reviewed the findings from RCT to assess the impact of dietary interventions (whole-of-diet approach) on both depression and anxiety. The good news is that many of the papers concluded that dietary interventions were effective in the management of depression, and at times was comparable to medication and psychotherapy. The evidence was less strong regarding anxiety management.

MedDiet

• Rich in fruits, veg, nuts, seeds, legumes, fish, lean poultry, EVOO
• Preference for selecting wholefoods and low in processed foods.
• Eat in a social environment - promotes social engagement
• Long-term treatment with the Mediterranean diet on depression for patients may be beneficial.
• Anti Inflammatory foods seen as in the MedDiet - reduction in proinflammatory cytokines which can assist with neurotransmitter development/uptake.

Western Diet

Study of 110 healthy 18-22 year olds were randomised to either a Western diet for a week or their usual diet. Those on the Western diet (toastie and m/shake or waffles for breakfast and fast food meal for lunch and dinner)

showed impairments in learning and memory and also reduced appetite control.

https://royalsocietypublishing.org/doi/10.1098/rsos.191338

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3056912/

Gut microbiome - bidirectional communication between gut and brain

• Our gut bacteria can have a profound impact on our mood and mental health - many animal and human studies have looked into this.
• Animal data + human data - bacteria important for physical and mental health. Diet is the most important component to affect the gut microbiota.
• Gut microbiota interact with all cells in the body and also have an impact on our genetic profile
• Prebiotic fibres to feed our gut bacteria - when gut bacteria and thriving this is likely to have a positive impact on our mood and mental health - diversity of fibre (diversity is a marker of food gut health). When our bacteria ferment dietary fibre they also produce neurotransmitters - more than 90% of serotonin is produced in the gut (still unsure if that makes it to the brain across the blood brain barrier).
• Probiotics - Probiotic supplementation showed a significant reduction in depression - particularly Lactobacillus and Bifidobacterium. Include probiotic rich foods - kombucha, kimchi, yoghurt, kefir.
• Polyphenols can also help increase the growth of our gut microbiota.
• Poly + monounsaturated fats - from fish, nuts, EVOO
• Listen in to episode 3 but also stay tuned for an update on gut health in episodes coming soon!

Other mood boosting strategies

• Covered nutrition in depth.
• Exercise has been linked to improved mental health
• Eating with others - mediterraneans do this well
• Sleep - aim for 7-8 hours per night
• Meditation has been shown to help build more brain cells = better long term brain health. Exercise does the same. Improved connectivity.
• Novelty - learning a new skill, language, dance, route home from work, meeting new people, changing hair colour or clothes style - may increase plasticity of the hippocampus (the ability to create new connections between neurons).

Upgrade Your Health Guide

http://oncorenutrition.com/eat-our-words/

Food and Mood: Improving Mental Health Through Diet and Nutrition

- link in shown notes to online course for anyone interested in learning more or using diet as a tool to support good mental health.