We are currently living in an era of increased brain inflammation and earlier rates of cognitive decline. In 2022, it was estimated that almost 400,000 people in Australia were living with dementia. This is 300x more than was found in 2010.
More research continues to surface, revealing the short and long term effects that certain foods and nutrient deficiencies have on our brain. Additionally, new findings on genetic mutations are evolving and how this can affect the way in which we metabolise nutrients leading to particular deficiencies.
1. Inflammatory foods
Sugar We know it’s not great for us, but how exactly does it impact our brain? Sugar stimulates the dopamine reward centre. Studies have shown that it is more addictive than cocaine. One of the mechanisms in how it is addictive is due to that fact that when we are in a hyperglycaemic state, the hypothalamus can no longer respond to emotions. This is why ‘comfort eating’ sweet foods is common. Additionally, some researchers believe insulin deficiency is central to the cognitive decline of Alzheimer's disease. They have coined the condition ‘type 3 diabetes’. This is due to neurons in the brain becoming unable to respond to insulin, which is essential for basic tasks, including memory and learning. Insulin resistance is commonly due to a prolonged hyperglycaemic state.
Seed oils and trans fats
High fat diets can stimulate inflammatory pathways, cause oxidation and cell damage. Consuming trans fats can increase your risk of depression by as much as 48 percent, according to studies. When we eat trans-fats it is incorporated into brain cell membranes and alters the ability of neurons to communicate. It can also reduce levels of serotonin. Processed foods/ preservatives
Studies have shown that preservatives cause neuronal degeneration, shrinkage and neuronal death. Decreased brain levels of reduced glutathione (natural antioxidant). As well as induced elevation inflammatory markers in brain tissue. Artificial sweeteners like aspartame have been linked to behavioural and cognitive problems. Possible neurophysiological symptoms include learning problems, headache, seizure, migraines, irritable moods, anxiety, depression, and insomnia.
Gluten sensitivity triggers gut dysbiosis, neuroinflammation, gut-brain axis dysfunction. Gluten is also known to exacerbate gut permeability, allowing toxins and food particles to enter the blood stream and further cause inflammation in the body.
2. Nutrient deficiencies
B1- The brain uses this vitamin to help convert glucose or blood sugar into fuel, and without it the brain rapidly runs out of energy. This can lead to fatigue, depression, irritability and anxiety. Food sources = meat, seeds, dairy. B6- vitamin B6 is a cofactor in the tryptophan-serotonin pathway. It is also an important part of methylation. Food sources = Meat, greens, legumes, bananas, avocado.
B9- Essential for the methylation pathway. Food sources = leafy green vegetables, organ meats.
B12- Vitamin B12 are appropriate red blood cell formation, neurological functioning, and DNA synthesis. Deficiency of Vitamin B12 can result in haematological changes, neurological and psychiatric problems, which can manifest as irritability, changes in personality, depression, and memory loss. It is also known to worsen depression by excitotoxic reactions caused by the accumulation of homocysteine (due to undermethylation). Neurotransmitters are required to conduct the signals from one neuron to another, with the help of pre- and post-synaptic junctions. The malfunctioning of any of these pathways can lead to depression. Lower Vitamin B12 levels are also known to increase the risk of cognitive decline, Alzheimer's disease, and dementia. Food sources = meat, eggs, yoghurt, seafood.
Amino acids – For dopamine and norepinephrine, both L-tyrosine and L-phenylalanine can be utilized. For serotonin production, L-tryptophan is needed. Normally, when we acquire amino acids, they are consumed as long chains of protein molecules in protein rich foods, like meat, eggs, and beans. While most people consume adequate protein, they can still be deficient in amino acids. The reason is typically due to compromised digestion (not enough stomach acid and digestive enzymes). With low levels of dopamine and serotonin, for example, you may feel depressed or overly aggressive.
Magnesium- Magnesium helps you to relax by stimulating the production of melatonin and serotonin which boost your mood and help you sleep. Magnesium also reduces the production of cytokines and cortisol, which lead to increased inflammation and stress.
Food sources = leafy greens, cacao, nuts and seeds. Vitamin D - research shows that the enzyme which converts vitamin D into its active form, is found not only in the kidney but also in the brain. This suggests an important role of vitamin D in the regulation of cognitive and affective processes. Several studies have confirmed a link between vitamin D insufficiency and mental disorders such as schizophrenia, autism, and depression.
Vitamin D also plays an important role in serotonin and melatonin regulation, which further indicates the relevance of vitamin D in mental health, especially the regulation of mood and sleep. Food sources= cod liver oil, organ meats and mushrooms that have been left in the sun. Best synthesised from direct sunlight.
Iron – Iron binds oxygen to red blood cells. This delivers oxygen to all your organs including your brain. A deficiency can lead to brain fog, inability to concentrate, anxiety and depression. Food sources = red meat, leafy greens, seeds, legumes, molasses.
3. Genetic issues – MTHFR The methylation process in the the body is responsible for detoxification, supporting DNA (turning genes on and off), producing energy, reducing inflammation, synthesising neurotransmitters, homocysteine metabolism, protein methylation, phase 2 liver detoxification and supporting immune function. Inadequate methylation capacity can lead to birth defects, depression, cognitive decline, allergies and cancer. Impaired methylation has even been associated with autism and exacerbation of spectrum disorder symptoms. Support of methylation markers has been associated with rapid return of speech, improvement of behaviour in ASD and ADHD spectrums.
Higher levels of homocysteine affect the DNA formation and overall turnover of red blood cells (RBCs), causing the development of megaloblastic or pernicious anaemia, ultimately affecting the cognitive ability and mood of the patient.