The gut microbiome—the bacterial community in our digestive tract—continues to be a hot topic as scientists find more ways in which it influences human health, from improving resistance to colds and flu to enhancing the ability to maintain a healthy weight. And scientists have recently discovered that a healthy gut may also help fight serious lung diseases.
A study at the University of Michigan in Ann Arbor found errant gut microbes in the lungs of patients with acute respiratory distress syndrome (severely inflamed, fluid-filled lungs). “We suspect that the gut wall gets leaky and gut bacteria ‘escape’ to the lungs,” says researcher Robert Dickson, MD. The misplaced gut bugs contribute to the disease, and this discovery may lead to new treatments for the condition, a leading killer of patients in intensive care units for which there is no effective medical treatment. Other lung diseases that may be influenced by the gut microbiome include chronic obstructive pulmonary disease (COPD), cystic fibrosis, pneumonia, and even lung cancer.
Did You Know?
Bacteria make up about 2 percent of a person’s body weight.
Solving the Leaky Gut Problem
Also referred to as hyperpermeability of the gastrointestinal tract, leaky gut means that toxic particles, which can be eliminated if they remain in the digestive tract, escape into the blood and circulate. The leakiness triggers systemic inflammation and contributes to a variety of ills, including weight gain, inflammatory bowel disease, type 2 diabetes, heart disease, mental decline, and even Alzheimer’s disease or other forms of dementia. Probiotics can help reverse this condition.
At the University of North Texas Denton, the first human study of its kind measured levels of “endotoxins,” which are markers of leaky gut, in a group of 28 healthy men and women. Those in the study were especially vulnerable to elevated levels of endotoxins after eating a high-fat meal such as thin-crust pizza. After 30 days of supplementation with a probiotic combination (Just Thrive Probiotic & Antioxidant), levels of endotoxins after a high-fat meal were 42 percent lower, indicating lower odds of a leaky gut and related ills. In contrast, among people taking a placebo, endotoxin levels were 36 percent higher.
Types of Probiotics
The supplement used in the study cited above contained a combination of “spore” probiotics. Spores are a dormant form of bacteria with a natural protective coating that prevents them from being destroyed by stomach acid and enables them to travel to the intestines, where the bacteria can emerge, much like a butterfly from a cocoon.
About one-third of the bacteria in a healthy human gut produce spores, according to the Sanger Institute, a nonprofit research organization in the United Kingdom. In nature, spore-forming bacteria are mainly found in soil. For bacteria that don’t produce spores, some probiotic supplements have a protective coating to prevent stomach acid from destroying beneficial microbes before they can reach the intestines.
The names of spore probiotics begin with “Bacillus.” Names of popular probiotics that begin with “Lactobacillus” or “Bifidobacterium” are not spores.
Studies have found benefits—including improved weight loss—with all types of probiotics.
What are the benefits of probiotics?
Studies have found benefits with all types of probiotics. For weight loss, a review of 25 studies following more than 1,900 people found that supplements with multiple types of probiotic bacteria produced the most weight loss, more so if taken for at least 8 weeks. Other benefits include prevention or relief from:
- Antibiotic side effects
- Colds and flu
- Hay fever
- Irritable bowel syndrome
- Digestive side effects of cancer therapy
- Impaired mental function in people with Alzheimer’s
- Toxicity from mercury, arsenic, and cadmium
- Vaginal infections
- Depression in people with IBS
- Unhealthy blood-sugar levels in diabetics
Feeding Good Gut Bugs
Although all types of fiber from plant foods are an essential part of a healthy diet, some foods are especially good sources of prebiotics—special types of fiber that nourish beneficial gut bugs. These foods include asparagus, Jerusalem artichoke, leeks, onions, and tiger nuts.
In supplements, prebiotics include inulin, fructooligosaccharides (FOS), galactooligosaccharides (GOS), and xylooligosaccharides (XOS). A study at the University of California Los Angeles found that 1 gram daily of XOS reduced bad gut bacteria and enhanced beneficial bacteria in people who were healthy, overweight, or had elevated levels of blood sugar.