Your gut microbiota plays a crucial role in your health, and the 100 trillion or so microbes living in your gut feed on the foods you eat. In this way, your diet influences your health not just by the micronutrients it contains, but also by how it affects the bacterial colonies residing in your intestinal tract.
Justin Sonnenburg is an associate professor of microbiology and immunology at Stanford, and Erica Sonnenburg is a senior research scientist in the Sonnenburg Lab, which is part of the department of microbiology and immunology at Stanford who have looked at the interactions between diet and gut bacteria—specifically those living in your colon—and the effects on your health.
The Importance of Fiber for Gut Health
Dietary fiber promotes health by fueling beneficial bacteria to produce compounds that help regulate your immune function. For starters, these compounds help increase T regulatory cells, specialized immune cells that help prevent autoimmune responses and more. Via a process called hematopoiesis, they’re also involved in the formation of other types of blood cells in your body.
Few Americans get the standard recommendation of 30 to 32 grams of fiber per day, and when fiber is lacking, it starves these beneficial bacteria, thereby setting your health into a downward spiral. As noted by Patrick:
“This has an effect not only on the immune system and autoimmune diseases but also results in the breakdown of the gut barrier, which leads to widespread inflammation and inflammatory diseases.”
High-Fiber Diet Reduces Mortality And Stroke Risk
Mounting research suggests that a high soluble fiber diet can help reduce your risk of premature death from any cause, likely because it helps to reduce your risk of a number of chronic diseases.
This includes type 2 diabetes, heart disease, stroke, and cancer. Studies have also linked a high-fiber diet to beneficial reductions in cholesterol and blood pressure, improved insulin sensitivity, and reduced inflammation—all of which can influence your mortality risk.
Most recently, a meta-analysis evaluating the impact of a high soluble fiber diet on mortality with pooled data from nearly 1 million Europeans and Americans found a 10 percent drop in mortality risk with each 10-gram per day increase in fiber.
Organic psyllium is one of the best ways to radically increase your intake of soluble fiber. I believe most people could benefit from more fiber and personally take about 3 ounces of organic psyllium a day, which supplies 75 grams of soluble fiber, about half of my daily fiber intake.
Other recent studies have produced similar results.Research published in 2013 found that for every 7 grams more soluble fiber you consume on a daily basis, your stroke risk is decreased by 7 percent. This equates to increasing your consumption of fruits and vegetables by about 2 additional portions per day.
Your gut microbiome also exerts a powerful influence on your weight
Gut microbes known as Firmicutes have been detected in higher numbers in obese individuals, who also may have 90 percent less of a bacteria called bacteroidetes than lean people. In a Medscape interview published in April, 2015, Dr Martin Blaser, who heads up the Human Microbiome Center at New York University, discussed the links between your gut microbiome, obesity, and chronic disease.
In his book, “Missing Microbes: How the Overuse of Antibiotics Is Fueling Our Modern Plagues,” Dr. Blaser attributes rising obesity and disease rates to factors that have altered the microbial composition of our microbiome. This includes:
– Increased rates of C-sections
– Excessive use of antibiotics in medicine
– Inappropriate use of antibiotics in food production.
– Dietary changes, switching to diets low in fat and high in carbohydrates
– Switching from breast milk to infant formula. This dietary change, he believes, is the most adverse of all
Moreover, he believes the effects are “cumulative over time and cumulative across generations,” noting that: “We’ve done studies in mice in which we can show that giving mice antibiotics early in life makes them fat. Putting mice on a high-fat diet makes them fat, and putting them on both together makes them very fat, suggesting the idea of additive risk.”
How Gut Bacteria Helps Regulate Your Appetite
Recent research has shed even more light on the links between gut bacteria and weight problems. Here, the researchers decided to investigate the possibility that bacterial proteins might act directly on appetite-controlling pathways. The hypothesis was that since bacterial survival depends on maintaining a stable environment, the bacteria must have some way of communicating their nutritional needs to the host.
Indeed, this is what they discovered. In essence, it appears gut bacteria play a role in appetite regulation by multiplying in response to nutrients, and stimulating the release of satiety hormones. The research also suggests bacteria produce proteins that can linger in your blood for a longer period of time, thereby modulating satiety pathways in your brain.
“The researchers studied the growth dynamics of E. coli K12 … when exposed to regular nutrient supply … After 20 minutes of consuming nutrients and expanding numbers, it was found that E. coli bacteria from the gut produce different kinds of proteins than they do before feeding. The 20-minute mark coincides with the time taken for a person to begin feeling full or tired after a meal …”
The researchers began to profile the bacterial proteins before and after feeding … ‘Full’ bacterial proteins were found to stimulate the release of … a hormone associated with feeling full while “hungry” bacterial hormones did not …
Another recent studyfound that probiotics helped protect against weight gain. The probiotic product in question was a commercial product containing multiple bacterial strains, including Lactobacillus acidophilus and Bifidobacterium longum. After four weeks, men who consumed this probiotic mix gained less weight and fat compared to those who received a placebo.
Healthy Sources of Fiber
It’s easy to be fooled when it comes to fiber. Most processed grain products claim to supply you with fiber, but breads and cereals are far from ideal. Not only do cereal grains promote insulin and leptin resistance, which is at the heart of obesity and chronic disease, most are also contaminated with glyphosate.
For example, about 15 years ago, farmers began dousing non-organic wheat with glyphosate just before harvest—a process known as desiccation—which increases yield and kills rye grass.
As a result, most of the non-organic wheat supply is now heavily contaminated with glyphosate, which has been linked to celiac disease and other gut dysfunction. Needless to say, this is the exact converse of what you’re trying to achieve by adding fiber to your diet. Instead, focus on eating more vegetables, nuts, and seeds.
The following whole foods, for example, contain high levels of soluble and insoluble fiber. Psyllium in particular has been shown to improve glycemic control in people at risk for Type 2 diabetes.
– Organic psyllium seed husk
– Flax hemp, and chia seeds
– Vegetables such as broccoli, cauliflower, Brussels sprouts, peas, green beans
– Root vegetables including onions, sweet potatoes, and jicama (Mexican yam bean)
– Raw almonds
A major culprit in our low fiber diet is food processing, which removes many of the vital nutrients. Add to that the use of agricultural chemicals such as glyphosate, and decimated soil nutrients secondary to industrial agriculture , and it should be clear that what we’re eating today is very far indeed from what our ancestors ate even two or three generations ago. As a result, our microbiome is changing, and it’s changing for the worse.
Soluble fibers, such as psyllium, are ideal nourishment for beneficial bacteria that assist with digestion and absorption of your food, and play a significant role in your immune function. Opting for an organic version of psyllium will prevent exposure to pesticides, herbicides and chemical fertilizers that are present in nearly all commercial psyllium products.
I also recommend choosing one that does not contain additives or sweeteners, as these tend to have a detrimental effect on your microbiome. Sugar, for example, feed potentially pathogenic microorganisms, which is the converse of what you’re trying to achieve.
Many women at menopause find they are carrying extra weight, often due to oestrogen dominance, but a healthy diet is a key factor in helping to keep the weight off.