Gut Bacteria and Weight is there a link?
According to the NHS, 67% of men and 62% of women were classed as overweight or obese in the UK in 2019.
However, the method of counting calories does not overall seem to work as it is estimated that nearly 65 percent of dieters return to their pre-dieting weight within three years, and the quicker you lose the weight the quicker you put it back on.
This suggest that perhaps there is a lot more going on that calories in calories out has had its time. Dr Tim Spector, a professor of genetic epidemiology at King’s College London said that “Really, that thinking has now been exposed as completely flawed.”
In his book “The diet myth” Dr Tim Spector a professor of genetic epidemiology at kings college London, who has published over 700 academic papers, a large proportion on the causes of obesity, believes that : “changes in our microbiome is likely to be responsible for the worldwide obesity epidemic” .
In a study by Vanessa Ridaura, Jeffrey Gordon and colleagues at Washington University in St. Louis researchers found pairs of identical human twins, in which one was obese and the other lean. They transferred gut bacteria from these twins into mice and watched what happened. The mice with bacteria from fat twins grew fat; those that got bacteria from lean twins stayed lean. They also saw differences in the way the mice metabolized food.
A recent case report described a patient who underwent a successful fecal microbial transplant for Clostridium difficile infection but then developed new-onset obesity after receiving stool from an overweight donor.
There seems to definitely be someting going on there……
The proposed mechanisms by which the gut microbiota could contribute to the pathogenesis of obesity and the related metabolic diseases include:
1- THE DIVERSITRY AND COMPOSITION OF THE GUT BACTERIA
Many scientific studies show that lack of diversity in the microbiome of overweight and obese individuals is common.
Spector tested 49 volunteers all on the same diet. After 6 weeks they all lost weight but then some stabilised and others started to put the weight back on. The key difference was the variety of their gut bacteria. The volunteers who had the least variety put the weight back on.
In The diet Myth he explains that he can predict obesity better by looking at microbes than genes!
When compared to healthy humans, people who are overweight tend to have a reduced abundance of Bacteroidetes and an increase in Firmicutes. This ratio is associated with an increase in low-grade inflammation and greater extraction of energy from food. This in turn can lead to elevated blood sugar and fat levels. Both of these markers are associated with overweight and obesity.
2 - GUT MICROBES EXTRACT ENERGY FORM FOOD AND REGULATE OUR APPETITE HORMONES
Another mechanism put forward is that some of us have microbe’s where they can eat plenty of carbohydrates and others can’t as they extract more calories form the same amount of food. So for some of us a calorie might not be a calorieafter all but many more.
Scientists also agree that the gut microbiota plays a role in regulating the activities of your gut lining, appetite control, and even blood glucose control.
Low diversity of gut bacteria leads to less production of short chain fatty acids such as Butyrate and acetate. Healthy gut flora digest food by fermenting it. When they ferment certain types of fibre, they create butyrate.
Normal-weight people have more butyrate-producing bacteria in their gut than obese people.
Acetate and butyrate are two short-chain fatty acids that bind to receptors on the cells of the gut lining, and help regulate fat storage and control appetite.
These receptors induce the release of the gut hormones that regulate appetite: (peptide YY and GLP-1). In normal concentrations, they help to suppress appetite, but too little could be contributing to some of use feeling hungry quicker
The good news is that you can influence these factors with what you eat The best way to optimise butyrate production is to adopt a high-fibre diet that will encourage butyrate-producing bacteria of the microbiome
3 - SOME BACTERIA MAY BE PROTECTIVE AGAINST WEIGHT GAIN
Some microbes help protect us from weight gain and obesity by strengthening the gut lining and maintaining healthy metabolic markers.
Akkermansia muciniphilahis is a bacterium that has been found to be more abundant in lean people and less abundant in patients with obesity. Studies indicate that Akkermansia can help the body control sugar and fat metabolism, both of which are an issue in overweight and obesity.
Managing how much glucose enters your bloodstream is important for weight management. When you have healthy levels, your body uses it as energy and you don’t put on weight. But when there’s too much, insulin tells the cells to store all the extra in your fat cells - and they’re usually around the waist.
If you take the gut flora from a normal person and transplant them into the colon of someone with metabolic syndrome, the recipient’s insulin sensitivity improves along with their ability to ferment carbohydrates into butyrate.
Akkermansia also produce nutrients that support other beneficial bacteria in our gut microbiome. A. muciniphila is key because it can increase the thickness of the mucus lining in your gut, thereby improving gut barrier function.
Polyphenols such as Flaxseeds, Cloves, cocoa powder and dark chocolate, berries may boost your Akkermansia abundance. They also love fish oil but not saturated fats. Fasting may also help.
3 - INCREASED INTESTINAL PERMEABILITY.
The Western diet and obesity are both associated with increased permeability of the gut lining, this could mean that your gut is busy extracting energy for longer periods, which means there’s more energy for your body to store as fat.
It can also let more lipopolysaccharide (LPS) into the body. This inflammatory molecule is found in the outer layer of some gut bacteria, and elevated LPS levels are also detected in blood samples of obese patients. Inflammation is associated with obesity.
Antibiotics:
The use of antibiotics may contribute to the development of obesity through the impact on the gut lining that creates inflammation. When the gut lining is damaged signals are not working properly. You could be exposed to antibiotics through direct prescription or in the US particularly where 80 % of antibiotics ate used on cattle and are knows to make them put weight on.
FOODS TO NOURISH YOUR GUT AND PROMOTE WEIGHT LOSS.
THE 3 PS :
Beneficial gut microbes love plant foods and good fats so eat whole plant foods like vegetables, fruit, seeds, and nuts, as well as grains and legumes.
Polyphenol foods: green tea, red wine. Cocoa, filtered coffee, blueberry, blackcurrant, raspberry, prune, apple, flaxseed hazelnut almond pecan nuts, black and green olives, red onion Extra virgin olive oil, herbs oregano, ginger, cinnamon, basil, curry powder , sage , thyme.
Prebiotics : All fruits and vegetables
Probiotcis : Live yogurt, Kimchi, Kombucha, Kefir, unpasterised cheeses.
You should get at least 30g of fibre every day from whole foods.
Research also shows that people who eat 30+ different plants of the food rainbow (red, orange, yellow, green, and purple/blue) every week have the most microbiome diversity.