The organ systems in our bodies are often looked at independently, but the truth is - they never work in isolation. Our organs weave a clever web of interconnected systems, each playing a crucial role in maintaining our overall health and wellbeing.
One such example is the liver, which may seem unrelated to the nervous system, but today I’d like to share with you why a compromised liver can rapidly unravel your neurological wellbeing.
The Liver: The Busiest of Organs
Our liver is a remarkable organ that performs a multitude of critical functions. Best known as a key driver of our detoxification capabilities, many of us may not realise the volume of functions it performs.
Here's a brief overview of its key functions:
Detoxification
Your liver plays a central role in detoxifying your body by metabolising and neutralising harmful substances, such as drugs, alcohol, and toxins from the environment.
Metabolism
Your liver helps regulate your glucose levels by storing and releasing glycogen, which is vital for maintaining stable blood sugar levels. The liver also metabolises fats and produces essential proteins.
Nutrient Storage
Your liver stores important vitamins and minerals, such as vitamins A, D, E, K, and B12, as well as iron and copper.
Bile Production
Bile is produced by our liver, and concentrated by our gall bladder. Bile aids in digestion by emulsifying fats and facilitating their absorption in the intestines. Bile is essential to the absorption of our important fat-soluble vitamins and has a regulatory effect on our bowel function. Bile is also used as a carrier for substances such as cholesterol, hormones and bilirubin for excretion in bowel motions.
If the metabolic processes of the liver become compromised, it can initiate a spectrum of health problems that can spill over and compromise nerve and brain health.
The Role of the Liver in the Blood-Brain Barrier
Our brain is a delicate and highly protected organ. To maintain its integrity and function properly, it is shielded by a selective barrier known as the blood-brain barrier (BBB). The purpose of this barrier is to act as a shield and prevent harmful substances from freely entering the brain whilst also allowing essential nutrients and oxygen to pass through unencumbered.
Our liver plays a crucial role in supporting our blood-brain barrier integrity. It filters the blood coming from the digestive system before it reaches the brain. By metabolising toxins and harmful compounds, the liver ensures that these substances are not given the opportunity to cross the blood-brain barrier and harm the delicate nerve structures of our brain.
A robust, healthy liver means a healthier, cleaner blood supply to the brain. This protection is vital because even small amounts of toxins or inflammatory molecules reaching the brain can have significant effects on our cognitive function and nervous system health.
The Liver: A Regulator of Systemic Inflammation
In recent years, researchers have identified chronic inflammation as a significant contributor to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and multiple sclerosis. Our liver, as the body's primary site of inflammation regulation, plays a pivotal role in modulating our systemic inflammation.
When our liver is overwhelmed by toxins, excessive alcohol consumption, or a poor diet, it can become inflamed, triggering the release of inflammatory molecules into our bloodstream. These molecules can then cross our blood-brain barrier and induce inflammation in the brain.
Chronic brain inflammation is associated with cognitive decline, memory problems, and an increased risk of neurodegenerative disease. We know systemic inflammation can directly damage nerve cell structures and disrupt the normal communication between neurons, leading to a wide range of neurological symptoms. Recent research into the connection between liver damage and brain wellbeing by Yale University, showed that the scarring of liver tissues that can be present in many chronic liver diseases was associated with reduced cognitive ability and, in certain regions of the brain, reduced brain volume. It is believed this connection may be mediated significantly by inflammation.
The Interplay of Liver Health and Neurotransmitters
Neurotransmitters are the chemical messengers that enable communication between the nerve cells in our brain and nervous system. Proper neurotransmitter balance is essential for mood regulation, memory, and overall cognitive function. Surprisingly, our liver plays a role in maintaining this balance.
Several neurotransmitters, including serotonin and dopamine, are metabolised in the liver. These neurotransmitters are vital for regulating our mood, motivation, and pleasure. If our liver function is compromised, it can lead to imbalances in our neurotransmitter levels, contributing to mood disorders like depression and anxiety.
Furthermore, our liver is responsible for breaking down neurotransmitters after they have fulfilled their roles. If this process is impaired due to liver dysfunction, it can result in an accumulation of neurotransmitters in the brain, leading to altered brain function and disturbances to our mental wellbeing.
An Undernourished Liver Impacts Cognitive Health
The usage and storage of nutrients by the liver are essential for our brain health. Many vitamins and minerals stored in the liver, such as certain B vitamins, vitamin D, and iron, are critical for optimal brain function.
For instance, a deficiency in vitamin B12, which is stored in the liver, can lead to neurological problems like memory loss and confusion. Similarly, insufficient iron levels can cause cognitive impairment and fatigue, as iron is essential for vital oxygen transport to our brain. Maintaining a healthy liver ensures that these essential nutrients are readily available to support our brain function and protect against cognitive decline.
Choline is another nutrient that is vitally important to both our brain and liver. When choline levels become low, not only does this impact cognition, due to choline’s requirement in manufacturing acetylcholine for healthy memory - research also shows that choline is also important to our liver, and when we become deficient, we carry a greater risk of developing fatty liver disease.
You Can Support Your Liver and Optimise Brain and Nervous System Health
Now that we've highlighted the intricate connection between liver health and the wellbeing of the brain and nervous system, it's clear that taking care of your liver is an essential consideration for maintaining optimal cognitive function and preventing neurological disease risk.
Here are some practical steps to support your liver and, in turn, your brain and nervous system:
Maintain A Balanced Diet: Consume a diet rich in colourful fruits, vegetables, lean proteins, and healthy fats. Minimise processed foods, added sugars, and excessive alcohol intake, as these can place unnecessary strain on the liver.
Stay Hydrated: Drinking enough water is essential for hydration and optimises the circulatory and detoxification functions the liver performs.Loss of hydration status is also associated with cognitive losses. Keeping well-hydrated benefits the liver and the brain.
Exercise Regularly: Physical activity can help improve liver function, reduce inflammation, and support brain health.
Limit Alcohol and Sugar Consumption: Excessive sugar and alcohol can harm the liver, leading to fatty liver disease. This sets up a cascade of metabolic problems, which can impact cognitive health.
Manage Stress: Chronic stress can contribute to liver inflammation and negatively affect the nervous system. Practice stress-reduction techniques like meditation, yoga, or deep breathing. You can also employ herbal medicine adaptogens, like Ashwagandha or Rhodiola, to naturally support the body’s response to stressors.
Fibre Intake: Research has demonstrated that low-fibre diets place us at a greater risk for liver health problems. In fact, studies have shown that increasing fibre intake can lower the risk of NAFLD by up to 60%. Maintaining fibre intake provides essential fuel to our microbiota and is an easy way to benefit our liver health.
Check Your Vitamin Status: there are a range of vitamins that can support healthy liver function and/or, when low or deficient, can impair liver wellbeing.
Deficiencies in vitamins A, B3, B12, C, D, and E have been linked to NAFLD
Vitamin E is an important antioxidant that has been used therapeutically to address liver inflammation and liver fibrosis. Vitamin E supplementation is a common recommendation in NAFLD patients to diminish high oxidative stress.
Vitamin D is protective against NAFLD and cardiovascular disease. It helps to improve insulin sensitivity and reduce inflammation within adipose tissue which has been shown to benefit liver inflammation and fibrosis. Vitamin D deficiency has been connected to NAFLD, particularly in overweight individuals.
B vitamin status - particularly methyl folate and B12, as well as choline and methionine are important to the process of methylation, which is handled largely by the liver. When deprived of these nutrients the liver can become fatty which has flow-on on effects for liver longevity and systemic wellbeing.
Focus On Good Fats
A number of studies have shown that optimising dietary and/or supplemental omega-3 can reduce the risk of developing liver disease, particularly NAFLD. Whilst precise mechanisms are not fully understood, it is believed that the broad range of benefits of omega-3, such as anti-inflammatory, insulin-sensitising, and fat-metabolising effects are likely playing a role in this benefit. Furthermore, with the well-documented benefits omega-3 has on cognition, mood and brain wellbeing, ensuring your omega-3 status is optimised is a great way to benefit both the liver and the brain.
Studies have shown that consuming quality olive oil can provide a protective effect on cellular damage. In addition to being a monounsaturated (MUFA) oil, olive oil also contains a number of active phenolic compounds that have antioxidant and anti-inflammatory effects. Research has shown positive effects on liver steatosis (fatty hardening of liver tissues), and improvements in several lab health markers of liver inflammation and function. Choose a good quality olive oil for cooking and dressings.
Keep inflammation to a minimum: Inflammation overwhelms many of our important metabolic pathways, but in the case of the liver, inflammation can lead to damage to our liver tissues and function and this in-turn can elevate our neuroinflammatory burden and impact cognition and brain wellbeing. We can naturally support our liver to keep inflammation levels low by restricting inflammatory triggering foods, reducing our toxin or chemical exposures, eating a diet abundant in antioxidant polyphenols, keeping our gut healthy and adding natural anti-inflammatory foods and compounds into our daily regimes.
Hepatoprotective Herbs and Nutrients: There are a number of antioxidant herbal medicines that have been shown to protect and promote liver health. St Mary’s Thistle, Curcumin, Resveratrol and Green Tea have all been explored in research and have shown efficacy in improving liver health markers and controlling inflammation. Other nutritional antioxidant compounds like N-acetyl-cysteine and glutathione also help to support liver detoxification pathways, and protect liver cellular health and integrity.
Don’t Underestimate Liver Health in Cognitive Longevity
As one of our body's busiest and most depended-upon organs, the liver emerges as a silent hero. It plays an important role in influencing not only our physical health but also our cognitive function and nervous system wellbeing. By understanding the profound connection between our liver and brain health, we can take proactive steps to care for this vital organ. Prioritising a healthy liver through lifestyle choices and proactive care can pave the way for a sharper mind and a healthier nervous system, ultimately improving our longevity potential.
A thriving liver is not only your body's detox powerhouse but also an often untapped brain bio-hack.
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