Part 3. How the food we eat affects our mood and mental state.

    Our full physical and mental development is dependent on the food that we eat. Without sufficient food we would not grow, our bodies would be stunted and our physical organs would be undeveloped; moreover the development of our brain would be irrevocably harmed. But we also need high quality nutrition so that the body can repair itself fast , wounds can heal properly and cells can repair themselves as necessary. What we eat affects how our immune system works, how our genes work, and how our body responds to stress. All cells and tissues on our body , enzymes, neurotransmitters , hormones etc are made from the chemical components of the foods (and drinks) that we consume. So, we are literally what we eat.

    Additionally , the food we consume affects the microbiome of our gut. There is a plethora of studies showing how a healthier microbiome is going to decrease inflammation in the body, which consequently affects mood and  cognition. But this is just the tip of the iceberg. Known as the enteric nervous system (ENS), the gut’s brain is housed under the mucosal lining and between the muscular layers of the esophagus, the stomach, and the small and large intestines. The enteric nervous system is a rich and complicated network of neurons and neurochemicals that sense and control events in the digestive tract and, remarkably, can sense and respond to events in other parts of the body, including the brain. Amazingly, when scientists finally counted the number of nerve cells in the gut-brain, they found it contained over one hundred million neurons—more than the number of nerve cells in the spinal cord. What’s fascinating to note is that researchers have observed a significantly greater flow of neural traffic from the ENS to the head-brain than from the head-brain to the ENS. In other words, rather than the head informing the digestive system what to eat and how to metabolize, the focus of command is stationed in the belly. In addition to an extensive network of neurons, the entire digestive tract is also lined with cells that produce and receive a variety of neuropeptides and neurochemicals; the same substances, in fact, that were previously thought to be found only in the brain. These include serotonin, dopamine, norepinephrine, and glutamate. Even more eye-opening is that many hormones and chemicals previously thought to exist only in the gut were later found to be active in the brain. These include insulin, cholecystokinin, vasoactive intestinal protein, motilin, gastrin, somatostatin, thyrotropin releasing hormone, neurotensin, secretin, glucagon, and bombesin. All these foundings confirm the strong connection of the gut with the brain.

    Another compelling discovery is that the entire digestive tract is lined with specialised cells that produce and receive endorphins and enkephalins, chemicals that yield an array of sensations including joy, satisfaction, and pain relief. Most of the digestive sensations we are aware of tend to be negative ones, such as digestive upset and discomfort. Yet the warm gut feelings we sometimes experience after a satisfying meal or an exciting encounter are, in part, the enteric nervous system squirting pleasure chemicals at distant and neighbouring cells. As many of us know, the gut is often a barometer of our emotional states and stresses. Those who suffer from peptic ulcer, irritable bowel syndrome, heartburn, upset stomach, and other conditions would certainly concur. Perhaps this is why the gut produces an abundance of a class of chemicals known as the benzodiazepines. These psychoactive substances are the active ingredients in the prescription drugs Valium and Xanax. That’s right, your gut naturally produces these substances, in their exact chemical form, without a prescription and at no extra cost.

    But let’s have a look on the most common issues of mood and mental disorder. Anxiety for example is strongly related to a state of disturbance in the gut bacteria. When people experience unrelenting anxiety, then this means that they may be experiencing what is described by some theorists as an anxiety disorder. This includes panic disorder, obsessive-compulsive disorder, and social phobia and generalised anxiety disorder. Dr. Perlmutter considers that anxiety disorders are caused by a combination of factors which include the condition and processing ability of the gut, and the bacteria which inhabits it. He states: “When the balance of gut bacteria isn’t right, other biological pathways – be they hormonal, immunological or neuronal, aren’t right either. And the brain’s processing centres, such as those that handle emotions, aren’t right either. He quotes two significant experiments to substantiate his argument: In a 2011 study published in the Proceedings of the National Academy of Sciences, mice fed probiotics had significantly lower levels of the stress hormone corticosterone, than mice fed plain broth. (J.A. Bravo et al., 2011). The second study he describes was conducted at Oxford University. Neurobiologists found that giving people prebiotics (which is food for the promotion of good bacteria in the gut), resulted in positive psychological effects. What was observed by the Oxford researchers was that, compared to the placebo group, the individuals who had taken the prebiotics paid more attention to positive information, and less attention to the negative information. This effect, which has been noticed with individuals on antidepressants or anti-anxiety medication, indicated that the prebiotic group experienced less anxiety when faced with the negative stimuli. Also, the researchers discovered that the people who took the prebiotics had lower levels of cortisol, when measured via their saliva samples, which were taken in the morning, when cortisol levels are at their highest. Dr Perlmutter considers that these examples are relevant to the growing evidence of research studies that show a connection between mental health and gut bacteria, in particular in relation to anxiety.

    Another important factor in the management of anxiety involves regulating our blood sugar levels. Why can it make such a difference? The reason is because the sugar that we get in our bodies from processed foods such as white bread, white rice, white pasta, chocolates and fizzy drinks (to name a few junk foods) is immediately available, and immediately affects us. The body doesn’t have to work hard to digest the food and extract the nutrients. As a result, blood sugar rises rapidly and we can feel full of energy as a consequence. But this reaction is very bad for our body, which handles this sudden influx of sugar by releasing the hormone insulin. This informs our cells to mop up excess sugar very quickly. As a result of this activity by our insulin secretions, our blood sugar then drops, but it goes too low. Because of this drop, the hormone adrenaline is released. This is to initiate the unleashing of stored glucose, and then the experience of adrenaline is felt by the body. And as Dale Pinnock eloquently states “…adrenaline is to anxiety what petrol is to a bonfire”. You will then experience a change in your breathing rate; your heartbeat gets faster and faster; and your mind starts to race. These symptoms can be very unpleasant if you are already prone to experiencing anxiety.

    Additionally,  high calorie meals rich in trans-fats appear to stimulate immune activation.  Indeed, the inflammatory effects of a diet high in calories and trans-fatty acids have been proposed as one mechanism through which the Western diet may have detrimental effects on brain health, including cognitive decline, hippocampal dysfunction, and damage to the blood-brain barrier. Since various mental health conditions, including mood disorders, have been linked to heightened inflammation, this mechanism also presents a pathway through which poor diet could increase the risk of depression. This hypothesis is supported by observational studies which have shown that people with depression score significantly higher on measures of “dietary inflammation,” characterised by a greater consumption of foods that are associated with inflammation (eg, trans fats and refined carbohydrates) and lower intakes of nutritional foods, which are thought to have anti-inflammatory properties (eg, omega-3 fats).

    Blood sugar levels and trans-fats affect also anger levels. The are many studies that demonstrate the close relation between anger levels and diet. In a research  conducted by Professor Stephen Schoenthaler in 1983  for California State University, three thousand inmates of a prison were placed on a strict diet. The diet contained a marked reduction in sugary and refined foods. The results of this dietary restriction were as follows: There was a 25% reduction in assaults at the prison, a 21% reduction in anti-social behaviour, a 75% reduction in the use of restraints and a 100% reduction in suicides! A later study affirmed the validity of the results of Schoenthaler’s research. In 1983, in a double-blind study of 1,382 detained juvenile offenders on a sugar-restricted diet, the effects of this restricted diet were as follows: the anti-social behaviour dropped by 44% with the most outstanding reductions happening to the most serious offenders (Schoenthaler 1983). There is also research which suggests a link between trans-fats (including hydrogenated oils in processed foods), on the one hand, and aggression, irritability and impatience, on the other.  And, there have been several follow-up studies which have replicated and extended Schoenthaler’s results, demonstrating a strong link between healthy diet and more pro-social behaviour, indicative of better mood management and emotional control.  Of particular note is the finding that keeping the poor quality diet of prisoners, but adding vitamin and mineral supplements, plus fish oil supplements, will normally reduce anti-social behaviour, as levels of anger decline. And in the UK, between 1995 and 1997, at Aylesbury Young Offenders Institution, a placebo-controlled, randomised trial, was conducted by Dr Bernard Gesch (2002), in which young offenders were given food supplements (including vitamins, minerals and essential fatty acids), and it was found that they committed 37% fewer violent offences, while the inmates who received the placebo showed no such reduction; thus demonstrating that improved nutrition reduces angry outbursts (which were being fuelled by vitamin and mineral and fatty acid deficiencies).

So, which foods are recommended for improved mood and healthy mental state?

Generally, eating a balance of foods, mostly plants, gives us the nutrients we need for physical and mental health. There is no superfood for mental health. Our pattern of eating is what matters the most. A balanced and varied diet of whole and unprocessed foods provides the mix of nutrients we need to be at our best. All nutrients are important for physical and mental health. Here’s how foods from the five core food groups support our mental wellbeing:

• Fruit and vegetables provide us with fibre that feeds our good gut bacteria. Fruit and vegetables are important sources of the vitamins, minerals, and antioxidants that underpin our body’s core functions. Fermented foods, such as Kimchi , Kefir,  Kombucha or Sauerkraut, are also beneficial for our mental health, as they provide us with living good bacteria (also known as probiotics).

 

• Whole grains, cereals and legumes  are excellent sources of minerals, healthy fats, protein and fibre. They give us B vitamins, folate, and other vitamins which support brain health and functioning.

 

• Lean meats, including fish, and eggs are the best dietary sources of protein. Our body turns protein into many products, including brain chemicals that shape our mood. Moderation is key though – too much meat, particularly processed and fatty meats, can negatively affect our physical and mental health.

 

• Dairy foods like yoghurt provide us with living probiotics, which boost our gut health and in turn supports mental health.

 

• Healthy fats, especially omega-3, are essential for keeping our brain and nerves in tip-top shape. Great sources include olive oil, nuts, seeds, and oily fish like sardines, salmon, and mackerel.

 

• Water is vital for mental health. Our bodies are 65% water, and our organs (including our brain!) need water to function well. Drinking adequate water keeps our brains more alert. For most adults this is around 2 litres, or 8 cups, of water each day.

 

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