More than 2 years ago, Hippocrates, the father of modern medicine, suggested that all diseases begin in the gut.
Although some of his wisdom has stood the test of time, you may wonder if he was right in this regard.
This article tells you everything you need to know about the link between your gut and disease risk.
Table of contents
Disease Risk and Your Gut
Although Hippocrates was wrong to suggest that any disease starts in your gut, evidence shows that many chronic metabolic diseases do.
Your gut bacteria and the integrity of your intestinal lining strongly affect your health. ().
According to numerous studies, unwanted bacterial products called endotoxins can sometimes infiltrate your intestinal lining and enter your bloodstream ().
Your immune system then recognizes these foreign molecules and attacks them, leading to chronic inflammation ().
Some hypothesize that this diet-induced inflammation may trigger insulin and insulin-related factors in type 2 diabetes and obesity, respectively. It is also believed to cause fatty liver disease.
At the very least, inflammation has been strongly linked to many of the world's most serious diseases (, , ).
Nonetheless, keep in mind that this area of research is growing rapidly and current theories may be revised in the future.
ABSTRACT
Although not all diseases begin in the gut, many chronic metabolic conditions are thought to be caused or influenced by chronic inflammation of the gut.
Effects of chronic inflammation
Inflammation is your immune system's response to foreign invaders, toxins, or cell damage.
Its purpose is to help your body attack these unwanted invaders and begin repairing damaged structures.
Acute (short-term) inflammation, such as after an insect bite or injury, is generally considered a good thing. Without it, pathogens like bacteria and viruses could easily invade your body, causing illness or even death.
However, another type of inflammation – called chronic, low-grade, or systemic inflammation – can be harmful because it is long-term, can affect your entire body, and inappropriately attacks your body's cells (, ).
For example, your blood vessels, such as your coronary arteries, may become inflamed, as may structures in your brain (, ).
Chronic systemic inflammation is now thought to be a key driver of some of the world's most serious diseases ().
These include obesity, heart disease, type 2 diabetes, metabolic syndrome, Alzheimer's disease, depression and many others (, , , , ).
However, the exact causes of chronic inflammation are currently unknown.
ABSTRACT
Inflammation is your immune system's response to foreign invaders, toxins, and cell damage. Chronic inflammation – involving your entire body – is thought to be the cause of many serious illnesses.
Endotoxins and Leaky Gut
Your gut is home to billions of bacteria – collectively known as gut flora ().
While some of these bacteria are beneficial, others are not. As a result, the number and composition of your gut bacteria can greatly affect your physical and mental health ().
The cell walls of some of your gut bacteria – called Gram-negative bacteria – contain lipopolysaccharides (LPS), large molecules also known as endotoxins (, ).
These substances can cause an immune reaction in animals. During an acute bacterial infection, they can cause fever, depression, muscle pain and even septic shock ().
Additionally, these substances can sometimes escape from the intestine into the bloodstream, either constantly or just after meals (, ).
Endotoxins can either be carried into your bloodstream with dietary fats or pass through the tight junctions that are supposed to prevent unwanted substances from passing through your intestinal lining (, ).
When this happens, they activate immune cells. Although their amounts are too small to cause infection symptoms like fever, they are high enough to stimulate chronic inflammation, causing problems over time (, ).
Therefore, increased intestinal permeability – or leaky gut – may be the key mechanism behind diet-induced chronic inflammation.
When endotoxin levels in your blood increase to levels 2 to 3 times higher than normal, this condition is known as metabolic endotoxemia ().
ABSTRACT
Some bacteria in your gut contain cell wall components called lipopolysaccharides (LPS) or endotoxins. These can leak into your body and trigger inflammation.
Unhealthy diet and endotoxemia
Many endotoxemia studies inject endotoxins into the bloodstream of test animals and humans, which has been shown to cause rapid onset of insulin resistance – a key feature of metabolic syndrome and diabetes type 2 ().
It also leads to an immediate increase in inflammatory markers, indicating that an inflammatory response has been activated ().
Additionally, animal and human research indicates that an unhealthy diet can lead to high levels of endotoxins.
Animal studies suggest that a long-term high-fat diet can cause endotoxemia, as well as inflammation, insulin resistance, obesity, and metabolic diseases as a result (, , ).
Similarly, in a one-month human study in 8 healthy people, a typical Western diet resulted in a 71% increase in blood endotoxin levels, while levels decreased by 31% in people following a low-fat diet ().
Many other human studies have also observed that endotoxin levels increase after an unhealthy meal, including pure cream, as well as high-fat and moderate-fat meals (, , , , ).
However, because most high-fat diets or meals also contained refined carbohydrates and processed ingredients, these results should not be generalized to a healthy, high-fat diet based on real foods and including plenty of fiber.
Some researchers believe that refined carbohydrates increase endotoxin-producing bacteria and intestinal permeability, which amplifies endotoxin exposure ().
A long-term study in monkeys fed a high-refinite diet supports this hypothesis ().
Gluten may also increase intestinal permeability due to its effects on the signaling molecule zonulin (, ).
The exact dietary causes of endotoxemia are currently unknown. In fact, several factors are likely at play – involving food components, the configuration of your gut bacteria, and many other factors.
ABSTRACT
Animal and human studies show that an unhealthy diet can increase endotoxin levels in your blood, which can lead to metabolic disease.
The bottom line
Many chronic metabolic diseases are thought to begin in the gut, and long-term inflammation is considered a driving force.
Inflammation caused by bacterial endotoxins may be the missing link between an unhealthy diet, obesity and chronic metabolic diseases.
Yet chronic inflammation is incredibly complex, and scientists are just beginning to explore how inflammation and diet may be linked.
It's likely that the overall healthiness of your diet and lifestyle affects your risk of chronic inflammation and related conditions, rather than a single dietary cause.
So, to keep you and your gut healthy, it's best to focus on an overall healthy lifestyle with plenty of exercise and a diet based on real foods, lots of prebiotic fiber, and little junk food. transformed.
