Nutrition and Brain Health

The Gut and Brain Connection

Did you know that our bodies have 10 x more bacterial cells than they do human cells?  Technically, we are 10% human and 90% bacteria, right?  What is even more interesting is that our human DNA would fit in our big toe compared to our bacterial DNA taking up the rest of our bodies in comparison.  Therefore, what could possibly be more important than nurturing our good gut bacteria?  Our gut is lined with billions of bacteria and these bacteria ultimately determine our overall health.  Our bacteria even have the power to activate and deactivate certain genes therefore controlling our bodies.  Throughout our gut, these bacteria can interact with our brains through the gut-brain connection. 

95% of the Serotonin (a neurotransmitter that controls our sleep, appetite and mood) is produced in our gut.  The inner workings of our digestive system can therefore guide our emotions.  Neurotransmitters are highly influenced by our gut bacteria.  This highlights that the food we eat plays a critical role in our mental health.   Several studies have shown a correlation between lower incidence of mood-related conditions such as depression and anxiety in those who consume a less processed, Mediterranean-Style Diet when compared to those who consume a more processed, Western diet which is high in refined sugars.  Research shows that implementing a Mediterranean diet with a focus on plant-based nutrition may also reduce the risk of cognitive decline, such as conditions such as dementia. There is also a diet called The MIND diet (a combination of the Mediterranean and the DASH diet) which emphasizes natural, plant-based foods, specifically promoting an increase in the consumption of berries and green leafy vegetables, with limited intakes of animal-based and high saturated fat foods. The MIND diet has also been popularized due to its potential to be used as a prevention strategy for cognitive decline. 

The foods which are rich in the Mediterranean diet include vegetables, fruits, nuts, seeds, legumes, unprocessed grains plus small amounts of lean meat, chicken, fish, eggs and dairy products.  Plant-based foods are often also high in dietary fibre which is the main source of food for the microbiome (gut bacteria).  There are several different types of dietary fibre including soluble fibre, insoluble fibre and resistant starch.  Choosing a variety of plant-based foods is important to ensure that we develop diversity within our microbiome as this balance is linked to improved well-being.   

Omega-3s are important for protecting our cognitive function by helping us to maintain neuronal function and cell- membrane integrity within the brain. Omega 3 fatty acids include; alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).  Foods rich in these include oily fish such as salmon, trout, sardines and tuna.

Antioxidants are also essential to good brain health.  Foods which are rich in Antioxidants include fruits, vegetables, nuts, seeds and legumes.  The antioxidant levels in plant foods are over 64 times higher than the average animal-based foods.  Antioxidants are important for preventing cell and DNA damage, boosting the immune system and preventing inflammation throughout the body too.

It is also important to limit saturated fats and refined sugars as they can have a negative impact on brain proteins. These proteins are called neurotrophins, which protect the brain against oxidative stress and promote the growth of new brain cells.   Food which should be avoided or limited include deep-fried foods or highly processed and preserved foods, packaged foods like biscuits, and chips, cheese, animal fat and fat used for cooking such as butter, lard, ghee and cream.

Finally, the food that we eat can either be the most powerful form of medicine or the slowest form of poison.

Recipes

Salmon and Slaw– Serves 4

INGREDIENTS

• 1 ½ (10g) tablespoons olive oil
• Fresh Salmon 4 x 180g Fillets
• 200g Chinese cabbage, sliced
• 200g seedless grapes, cut in half
• 1 red capsicum, very thinly sliced (seeded)
• 1 carrot, grated
• ½ cucumber, sliced
• 2 spring onions, thinly sliced
• 1/2 cup fresh coriander leaves
• 1/2 cup fresh mint leaves
• 1 lime, zest finely grated, juiced
• 2 teaspoons honey
• 1/2 cup almonds, roasted, coarsely chopped
• Lemon wedges, to serve

METHOD

• Add the salmon, skin-side down to a large non- stick fry pan. Cook for 5 mins or until the salmon skin is crisp then turn and cook for another 2-3 mins, until the salmon is a soft pink center.
• Meanwhile, mix lime zest and 3 tablespoons of lime juice with the honey and 1 tsp of olive oil to make the dressing
• Mix the Chinese cabbage, grapes, capsicum, spring onions, carrot, cucumber, coriander and mint in a large bowl and divide among 4 plates
• Top with the cooked salmon and roasted almonds and serve with a wedge of lemon. Season as desired.

NUTRITIONAL INFORMATION
                                    Per Serving
Energy                         637(kcal)
Protein                         43g
Fat, Total                      40.8g
       -Saturated             7.8g
Carbohydrate              19.5g
       -Sugars                18.8g
Sodium                        96mg

Mediterranean Baked Eggplant - Serves 4

INGREDIENTS

• 2 large eggplants, halved
• 1 tbs olive oil
• 1 brown onion, diced
• 3 tomatoes, diced
• 1 large zucchini, grated,
• 400g mushrooms, sliced
• 1 carrot, diced
• 3 cloves of garlic
• 3 tbs tomato paste
• 1 tsp Dried Italian herbs
• 1 can of brown lentils, canned, drained and rinsed off
• 1 vegetable stock cube dissolved in ½ cup of boiling water
• 80g Parmesan Cheese

METHOD

• Preheat oven to 220°C and line a large baking tray with baking paper.
• Carefully scoop out eggplant flesh, whilst leaving around 2cm of flesh in the eggplant to form a boat shape, cut remaining flesh and put aside
• Heat a non-stick pan and add oil to cook onion, carrot, garlic and eggplant flesh until softened
• Add tomato, mushrooms, zucchini, tomato paste and herbs and combine, then add stock and lentils – heat through, once combined, thickened and heated through, transfer mixture in even portions into eggplant boats (prepared earlier)
• Bake eggplants for approx. 30mins or until brown and tender
• Serve topped with parmesan cheese

NUTRITIONAL INFORMATION
                                    Per Serving
Energy                         272(kcal)
Protein                         15g
Fat, Total                      15.2g
       -Saturated             5.1g
Carbohydrate               15.2g
       -Sugars                  4.3g
Sodium                         309mg

Flaxseed Cookies – Serves 15

INGREDIENTS

• 2 ripe bananas
• 1 egg
• 1 cup of rolled oats
• 1/2 cup ground flaxseed meal
• 1/4 cup unsweetened shredded coconut
• 1/4 cup sliced almonds
• ½ tsp of cinnamon
• ¼ cup dark chocolate chips

METHOD

1. Preheat Oven to 220 degrees and line a baking tray with baking paper
2. Place banana in a large bowl and mash, add rolled oats, flaxseed meal, shredded coconut, almonds, cinnamon, egg and chocolate chips – mix until combined well
3. Scoop out the mixture, making small balls and placing on baking tray, flatten with your hands until flattened slightly
4. Bake for about 20-30 minutes or until golden brown.
5. Cool for 10 minutes on a cooling rake before serving

NUTRITIONAL INFORMATION 
                                   Per Serving
Energy                        90(kcal)
Protein                        2.7g
Fat, Total                    4.8g
      -Saturated            1.9g
Carbohydrate             8.7g
       -Sugars               4.0g
Sodium                       6mg

References

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• Psaltopoulou T, Sergentanis TN, Panagiotakos DB, Sergentanis IN, Kosti R, Scarmeas N. Mediterranean diet, stroke, cognitive impairment, and depression: A meta-analyses. Ann Neurol. 2013;74(4):580-91.