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Feeling Stressed? It Might Be Your Liver Calling

Thomas Rutledge Ph.D.


Liver disease can be a direct cause of mental health symptoms because a compromised liver cannot prevent toxins in the blood from reaching the brain.


This article from 'Psychology Today' merits reading in full - as it includes some simple summary slides explaining why liver health is so critical to brain health.  The author, Dr Thomas Rutledge is both a Professor of Psychiatry and qualified health psychologist, specialising in the treatment of chronic medical conditions including heart disease, obesity, chronic pain, and diabetes.

Fatty Liver Disease - a Modern-Day Epidemic caused by excess sugar

The classic cause of 'fatty liver disease' used to be alcoholism, and traditionally, this condition was seen only in adults whose alcohol intake had been excessive for many years.

Over recent decades, however, so-called 'Non-Alcoholic Fatty Liver Disease' (NAFLD) has become commonplace - affecting 1/3 of the US population - and occuring not just in younger adults, but even in children and adolescents. By 2020, NAFLD was already affecting around 10% of the US paediatric general population (albeit with no initial obvious signs or symptoms), and at least 40% of those with obesity.

This relentless rise in fatty liver disease follows the major dietary shift from the late 1970s and early 1980s towards ultraprocessed foods rich in sugar and refined carbohydrates - and especially fructose, which (unlike glucose) is primarily processed in the liver, where it is turned to fat. 

Together with insulin resistance (also primarily caused by chronic excessive sugar intakes) an abnormal accumulation of fat in the liver forms part of the 'metabolic syndrome' that precedes the development of Type 2 diabetes and obesity. 

Having a fatty liver leads to chronic, systemic inflammation - as does obesity - so the combination typically creates a vicious spiral of inflammation, oxidative stress and chronic ill health.

Why Liver Health affects Brain Health

As this article explains, the chronic ill health that a fatty liver promotes also includes poor brain health, and an array of mental as well as physical symptoms - because the liver is responsible for innumerable basic metabolic functions that include dealing with all kinds of internal and external toxins, as well as constantly processing, recycling and producing nutrients and enzymes to keep all other systems and organs working. 

And all of these functions start to become compromised when the liver itself becomes fatty and inflamed.

The pioneering medical doctor, endocrinologist and pediatric obesity specialist Dr Robert Lustig was the first to really flag that 'sugar is the alcohol of the child' - and (building on earlier work by other pioneering researchers such as John Yudkin), to link the dramatic rise in our consumption of sugar, and particularly fructose, to the epidemic of obesity, Type 2 diabetes and other chronic, non-communicable diseases that has taken place since the 1980s.  See:

His most recent book 'Metabolical' provides a comprehensive account of how diets rich in ultra-processed foods (high in sugar, unhealthy fats and artificial additives) are the primary cause of most of the chronic, degenerative diseases that are undermining public health worldwide - and in his concise summary of how to reduce and reverse such diseases involves two simple recommendations:
  • 'Heal your liver', and
  • 'Feed your gut' 
To do both these things, the single most important factor for any individual is to 'Eat Real Food' - i.e. to consume mostly whole or minimally processed foods, and to avoid the ultra-processed, 'fake' foods and drinks that now make up the majority of typical diets consumed in the US, UK and many other countries. 

A well-balanced, 'real food' diet that provides all essential nutrients - together with the dietary fibre needed to support a healthy and diverse balance of gut microbes - will allow the liver to heal and regenerate, so that it can do its essential 'cleaning and housekeeping' jobs efficiently, and support gut, immune and brain health.

Another key issue is to minimise exposure to environmtal toxins (which includes some artificial food additives and chemcials used in some food packaging, as well as tobacco, alcohol or other 'recreational' drugs and many medications) - because these increase the burden of processing the liver has to do, and can also promote inflammation and 'oxidative stress', and damage the integrity of the gut lining.

For further information please see:

08/04/2023 - Psychology Today


Key points

Julia thought she must be losing her mind. Ostensibly in her prime, at age 35, and working at a successful law firm, she began having panic attacks out of the blue at work. Her sleep deteriorated. She suffered from spells of brain fog and began making embarrassing mistakes at work. Finally, after finding herself on the side of the road after missing a turnoff she'd made 10,000 times before, she decided to speak with her physician.
Thankfully for Julia, the doctor didn't refer her to mental health. Instead, results from her metabolic tests revealed a more likely cause of her symptoms: advanced liver disease. In Julia's case, identifying and treating her liver disease not only reversed her mental health symptoms, it may have saved her life.
Right now, unfortunately, millions of Americans are experiencing some of the same symptoms as Julia, suffering from the same invisible process of liver pathology, but not understanding the connection or getting the right treatment.

The liver and mental health.

Anxiety, depression, mood swings, memory loss, sleep impairment, personality changes.
If the above symptoms make you think "mental illness," then you may be overlooking a potential cause now affecting nearly half of American adults: fatty liver disease. This once-rare condition results primarily from factors such as excess body fat, poor dietary practices, and alcohol and substance abuse.
Although most people know about obesity and diabetes, far fewer have heard about fatty liver disease, their close metabolic cousin. And almost no one realizes how closely their liver health is connected to their mental health1. The aim of this post is to change that. 

The liver is a remarkable organ, both for its staggering contributions to our overall health and for its vast underappreciation by the general public. Outside of specialized liver doctors—such as hepatologists and gastroenterologists—even most healthcare providers do not realize the hundreds of life-enabling functions the liver performs each day.

The liver is the ultimate domestic engineer, working 24-7 to chemically neuter toxins in our blood before they infect our bodies. The organ functions as a nutritional warehouse for many essential vitamins and minerals and metabolizes medicines, alcohol, and other substances that would otherwise quickly jeopardize our existence.

The liver labors in these and many more roles in almost total obscurity, taking a relentless beating in the process of protecting us. Thankfully, the liver also just happens to be the organ equivalent of Wolverine—the fast-healing superhero mutant from the Marvel movies—in its ability to regenerate.
But even the marvelous liver has limits. Too much insulin, too much alcohol, or too much fructose, for example, and even the normally indomitable liver can no longer keep pace and begins to develop invasive fat within the liver tissue itself (the liver, under normal conditions, contains only trace amounts of fat).
The first signs of liver disease are sometimes recognized by physicians in the form of chronically elevated triglycerides, results on liver function tests such as alanine aminotransferase (ALT), or even by certain medical imaging procedures such as MRI and ultrasound. Caught early, fatty liver disease is treatable, frequently even reversible.
When these signs are missed, however, liver fat levels slowly progress, spiraling from the initial stages of inflammation to fibrosis and even cirrhosis. The latter cirrhosis stage is when the life-threatening process of liver failure ensues. As liver disease progresses across these stages, not only do many forms of physical illness become more likely, symptoms of mental illness also increase2.

Liver disease can be a direct cause of mental health symptoms because a compromised liver cannot prevent toxins in the blood from reaching the brain. These unwelcome invaders then proceed to wreak havoc on a range of critical brain functions.

Concentration, memory, mood stability, and the ability to tolerate and respond to stress are just a few of the potential mental capacities that can be impaired when toxins begin accumulating in the brain. Sadly, fatty liver disease remains a silent epidemic in the U.S., with most people unaware of the signs, symptoms, or causes3.

Healthy liver, healthy mind. What to do?

Treating fatty liver disease is a good news/bad news situation. The bad news is that there are no medicines approved by the FDA for the treatment of fatty liver disease. Unlike high blood pressure, cholesterol, or glucose, there is no simple prescription drug for fatty liver disease.
Instead, the most effective treatments for improving fatty liver disease and liver-induced mental health symptoms are behavioral. Losing body fat—particularly abdominal area body fat—, reducing sugar and fructose intake, lowering insulin resistance through exercise, sleep, and stress management, and limiting or eliminating alcohol and certain medicines that can harm the liver in high quantities such as acetaminophen (Tylenol), are some of the best ways to improve liver function (particularly at early stages).


Because fatty liver disease is becoming more common each year in the U.S. population, a growing number of people will experience the physical and mental side effects of the condition. Talk to your doctor about liver function tests during healthcare visits, and remember how this much this vital organ contributes to your health and well-being.


1. Labenz C, Huber Y, Michel M, et al.. Nonalcoholic fatty liver disease increases the risk of anxiety and depression. Hepatol Commun. 2020;4:1293–301.

2. Soto-Angona Ó, Anmella G, Valdés-Florido MJ, De Uribe-Viloria N, Carvalho AF, Penninx BWJH, Berk M. Non-alcoholic fatty liver disease (NAFLD) as a neglected metabolic companion of psychiatric disorders: common pathways and future approaches. BMC Med. 2020 Oct 1;18(1):261. doi: 10.1186/s12916-020-01713-8.

3. Ghevariya V, Sandar N, Patel K, Ghevariya N, Shah R, Aron J, Anand S. Knowing What's Out There: Awareness of Non-Alcoholic Fatty Liver Disease. Front Med (Lausanne). 2014 Mar 24;1:4. doi: 10.3389/fmed.2014.00004.