The liver is exposed to signals from the digestive tract and gut microbiome
Imbalances in the gut microbiome are connected with a higher risk for liver disorders associated with obesity, such as non-alcoholic fatty liver disease (NAFLD) . The severity of NAFLD and cirrhosis of the liver is associated with the degree of unhealthy (dysbiotic) gut bacteria .
A dysbiotic gut microbiome resulted in the accumulation of triglyceride fats in the liver . The gut microbiome has a large influence on the metabolism of bile acids and if disturbed may induce metabolic dysfunction, obesity and insulin resistance.
Ethanol and other bacterial products associated with the worsening of NAFLD may be related to a high amount of alcohol producing bacteria from the Proteobacteria genus of gut bacteria.
How cooking certain foods might alter the gut microbiota
A study published in Nature Microbiology explored how eating cooked food versus raw food affects the gut microbiome of humans.
Studies in mice found that those fed raw vegetables lost more weight than cooked-fed mice. This was thought to be because consumption of cooked vegetables impacted energy intake due to the greater digestibility of starch from the cooking process. This prompted the researchers to test the gut microbiota of five healthy women and three healthy men aged 24–40 who ate either raw or cooked plant-based meals for three consecutive days.
The researchers discovered that like mice, the study participants showed subtle but distinct differences after eating raw or cooked foods. The shifts observed in the gut microbiome could be due to the fact that cooking changes the physical structure of naturally occurring compounds found in foods making their calories more absorbable. Ref 26
Although the number of participants in this study was small, it shows the significance of controlling cooking method and not just nutrient intake when investigating the diet-gut microbiome connection.
Research into the links between cooking methods and gut health and weight gain is still in its infancy and more large-scale studies are needed to better understand how cooking foods could potentially affect weight.
There is a lot of controversy surrounding the safety of microwave ovens. Microwaving food is very different to traditional cooking, which transfers heat from within one object to the outside of another, which then penetrates within. Microwaves use radio-like waves (radiation) to generate heat from water inside the food. Excited particles within the food cells then cook your food. Using radiation to cook food raises concern in me and several of my scientific colleagues. After microwaving food it’s still cooking and you are ingesting active radio waves that may come into contact with intestinal bacteria and other microbes (the intestinal flora). Conventional science refutes that theory but it is controversial. Some research does show that microwaving foods may retain more nutrients as compared to more extended cooking methods, however other research shows that microwaves lessen the nutritional value of vegetables.
Microwave cooking is often associated with processed TV Dinners and supermarket off the shelf frozen meals high in preservatives; these are not conducive to a healthy gut microbiome.
It is proven that microwaving breast milk causes severe damage to its properties so this can be logically extended to other foods. Solid scientific evidence shows that breastmilk begins to lose its “superfood powers” when heated past 104 degrees F. Here are the ways that human milk deteriorates as it gets too hot in a microwave:
- Immunologic and anti-inflammatory components (such as IgA antibodies, lactoferrin protein, and lysozyme (infection protectant)) are decreased.
- Beneficial probiotic bacteria are destroyed.
- White blood cells are destroyed, in turn decreasing anti-infective properties.
- Fat content decreases which is vital for infant growth
- Inactivation of digestive enzymes.
If this occurs in breast milk it can happen to other foods which can become similarly devitalized. Damaged food is not conducive to a robust diverse microbiome.
How medications can affect the gut microbiome
I once saw an overweight man with a fatty liver and indigestion who had been on antacid drugs for over a decade without a break. The drugs are called Proton Pump Inhibitors (PPIs) and are taken by millions of people. He complained of fatigue, abdominal obesity and reflux. He showed me a photograph of the pictures of his stomach and small intestine that were taken during his recent gastroscopy. I was shocked! His stomach and duodenum were covered by a thick white layer of the yeast known as candida. His gut microbiome was overtaken by infection with candida and this was causing him severe problems. We treated the yeast infection and put him on a low carbohydrate diet and the natural antibiotic called BACTOCLEAR and he no longer needed the antacid drugs. He also found that his liver function improved and he lost the excess abdominal weight.
A lack of stomach acid production is a common cause of dysbiosis in older people or those with gastritis (stomach inflammation). It is vital to have adequate production of hydrochloric acid in the stomach as it acts as a natural antibiotic to prevent the bad bacteria from taking over. Many people with low production of stomach hydrochloric acid can benefit from taking supplements of hydrochloric acid (betaine HCL) in the middle of their meal and will find their gut microbiome improves a lot. This can make it easier to lose weight.
Research has shown that long-term weight gain in humans is related to low microbial diversity within the gut. This lack of diversity is encouraged by a low fibre diet high in processed foods. Try to eat unprocessed foods and cook them by using conventional methods such as roasting, baking, stir fry or steaming. Wash your raw produce well to remove unhealthy bacteria. Having a healthy gut microbiome will help to protect you from dangerous weight excess.
Dr Sandra Cabot and naturopath Victoria Taylor have done a podcast on “The connection between the gut and the weight”.
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