The microbiome is a mysterious place that’s become an increasingly important focal point in the wellness world. Dr. Joe Alcock of Pressed Juicery’s Medical Board is mapping out a few key facts about our microbiome, including how juicing can help our whole system shine. Strap on your science hats, kids – this one has a lot to take in, but is 100% worth the read…
Not too long ago, we thought we understood nutrition. Food is made of carbohydrates, protein and fat along with micronutrients such as iron and vitamins. Malnutrition is solved by meeting recommended dietary allowances in each of these categories. Obesity can be avoided by calculating energy requirements, paying attention to serving sizes and exerting self-control. Simple and scientific, right?
Now we know it is not so simple. We had overlooked a hugely important factor in nutrition and metabolism: the microbiota.
The Mystery of our Microbiome
The microbiota consists of at least 30 trillion microbes, mostly bacteria, that inhabit our bodies. These weigh about two kilograms (four and a half pounds) and can be found mostly in the colon. In the last ten years, research on the gut microbiota is generating new findings at a breathtaking pace. This knowledge has upended the conventional wisdom on diet, nutrition and obesity.
How is the microbiota important in nutrition? A compelling early piece of evidence came from experiments with germ-free mice. Mice in this study were genetically predisposed to be obese, but when they were raised “germ-free” – in a sterile environment without microbes – they stayed lean. When these germ-free mice made contact with microbes, they rapidly gained weight and became obese. This meant that when it comes to fatness, diet alone was not enough. Microbes in combination with diet were necessary to cause overweight and obesity.
Some scientists thought that gut microbes cause weight gain because they help us extract extra calories from our diet. We cannot digest fiber, aka complex carbohydrates, without the help of microbes. Extra energy from fermentation of complex carbohydrates is absent when there are no microbes to ferment them. But the story of obesity does not end there. Gut microbes also cause chronic inflammation. Inflammation happens when the gut microbiota undergoes unhealthy changes (dysbiosis), often caused by diet, and when gut microbes aren’t restricted to the inside of the gut.
Inflammation can happen after a single meal, caused by a bacterial cell-wall building block known as endotoxin. Endotoxin from bacteria spike the blood within an hour of eating cream and glucose. The appearance of these bacterial products activate immune cells and cause inflammation. Chronic inflammation is involved in many diseases, but especially obesity and diabetes, which are becoming epidemic in many countries. If gut microbes are the cause, they might provide a key to preventing the obesity epidemic.
Gut Microbiota + Juicing
One possible dietary solution involves the gut microbiota. This is possible because nutrients have different, often opposite effects on gut microbes and inflammation. In the previous study, orange juice prevented endotoxin from entering the blood and blocked inflammation. This was an early clue that not all calories are equal. Despite having a lot of calories, orange juice has been shown to block fat accumulation in mice, and is associated with healthy body composition in humans. The microbiota is the missing piece of the puzzle that underlies these findings. Plant compounds in orange juice known as flavanones inhibit the growth of harmful microbes. These ingredients shape the microbiome and strengthen the intestinal barrier. As a result, some plant ingredients protect us against inflammation from endotoxin and have healthy effects on our metabolism.
Recent research has examined how fruit and vegetable juices affect the microbiota, inflammation and obesity. Flavanones in some fruit juices were proposed to have beneficial effects on the gut microbiota. Researchers from the David Geffen School of Medicine at UCLA tested the effect of a fruit-juice diet on the microbiota in 20 volunteers. This diet caused a reduced number of Proteobacteria, a group that contains many pathogens, such as E. coli. The juice diet also changed the ratio of the most common bacteria in the gut, Firmicutes and Bacteroidetes. Previous research showed weight loss with similar changes in those microbes, and subjects in the UCLA study also lost weight. The effect of a three-day juice diet on body weight might be attributed to beneficial effects on the gut microbiota. It is unknown if those changes have lasting effects on body weight, but future work will examine that question.
Nutritionists advise that our diets are too low in fiber and vegetables, and too high in refined sugar and unhealthy fats. Microbiome experts propose that these diets are unhealthy mostly because of their effects on gut microbes and gut-barrier function. Fiber, healthy fats, along with fruits and flavanone-rich juices, promise to reduce the harm of the Western diet. We can thank our gut microbiotas for these dietary effects. Long-term studies will be needed to pinpoint what foods are healthiest for us and our microbiotas. In the meanwhile, it makes sense to pick foods that shape a healthy microbiota, and pay attention to emerging evidence on microbiota that gets more interesting every day.
Things to remember:
+ Nutrition is more than food labels. What we eat affects gut microbes and the gut barrier.
+ The microbiota has powerful effects on inflammation, weight gain and obesity.
+ Juices that shape the microbiome and strengthen the gut barrier may protect us from weight gain.
+ Three-day juice diets changed the gut microbiota and resulted in weight loss.
+ The gut microbiota is the key to understanding the link between diet and health.
The Chalkboard Mag and its materials are not intended to treat, diagnose, cure or prevent any disease. All material on The Chalkboard Mag is provided for educational purposes only. Always seek the advice of your physician or another qualified healthcare provider for any questions you have regarding a medical condition, and before undertaking any diet, exercise or other health related program.