Type 2 diabetes affects about one in ten adults and anti-diabetic medications are the fourth most commonly prescribed medications. Could the bacteria in our guts hold the key to restoring a healthy blood sugar metabolism?
In Type 2 diabetes, the body's ability to regulate blood sugar levels is gradually degraded. The condition typically develops in mid-life but is sometimes seen in children or young adults. If left unchecked, Type 2 diabetes (which affects about 1 in 10 Americans) can lead to a host of disfiguring and even deadly consequences: blindness, loss of limbs, kidney failure, heart disease, and even premature death.
Restoring the body's ability to deal with blood sugar naturally would be far preferable to treating it for the rest of your life with drugs.
Accordingly, a lot of time and money is spent screening and treating people for the disease. Metformin, a drug used to lower high blood sugar, is the fourth most commonly prescribed drug in the U.S. But of course, restoring the body's ability to deal with blood sugar naturally would be far preferable to treating it for the rest of your life with drugs.
Doctors screen for Type 2 diabetes by testing your fasting blood glucose levels. A reading of 99 mg/dL is considered normal. A reading between 100 and 125 is considered pre-diabetes and a fasting blood sugar over 125 signals Type 2 diabetes.
Although diabetes can lead to severe complications, it is largely asymptomatic in its early phases. An elevated blood glucose reading is usually the first indication of trouble. At that point, it's sometimes possible to turn things around with diet and lifestyle modifications. Losing weight (if you need to), getting more exercise, and eating a healthy diet can help you restore your body's ability to process carbohydrates.
Type 1 diabetes is a completely different disease in which the body's immune system attacks the pancreas. Although the consequences of poorly controlled Type 1 diabetes are similar to those of Type 2 diabetes, it cannot be prevented or treated with diet and lifestyle modification. Type 1 diabetics will always require insulin.
Eating sugar does not give you diabetes
We used to think that eating too much sugar would eventually result in developing Type 2 diabetes—a sort of "if-you-keep-making-that-face-it'll-freeze-that-way" comeuppance for dietary indiscretions. But eating a lot of sugar does not increase your risk of Type 2 diabetes unless it leads to obesity, which does increase your risk.
However, Type 2 diabetes also develops in people who are not overweight. A family history of Type 2 diabetes increases your risk. Your risk also goes up with age.
Recent research into the microbiome has revealed another interesting clue: People with Type 2 diabetes tend to have a different array of bacteria in their guts. Among other things, they seem to have a scarcity of the type of bacteria that produce butyrate as a by-product of their metabolisms. Butyrate is directly involved in glucose and insulin metabolism.
Could changes in gut bacteria lead to Type 2 diabetes?
It's hard to say whether the change in gut bacteria is the chicken or the egg here. Does the disease cause alterations in the gut microbiome? Or do changes in the gut microbiome give rise to the disease?
If we alter the composition of gut bacteria in people with Type 2 diabetes or prediabetes, would it improve their ability to metabolize sugar?
Even if we knew that the second scenario was true, it would still be hard to say whether those differences in gut bacteria were the result of a genetic disposition or of environmental factors such as diet. (Very likely, it's a combination of both.)
But even without knowing the answers to any of those questions, these observations raise another, more answerable question: If we alter the composition of gut bacteria in people with Type 2 diabetes or prediabetes, would it improve their ability to metabolize sugar?
A probiotic for blood sugar control
This was the question Colleen Cutcliffe set out to answer in a recent study. Colleen holds doctorates in biochemistry and molecular biology and is an expert in the formulation and manufacture of probiotic supplements. Her company, Pendulum, produces probiotic supplements that target various conditions. Last year, they created a new probiotic designed to restock the gut with the specific types of bacteria known to be scarce in people with Type 2 diabetes.
After 12 weeks, the people taking the probiotic formula saw meaningful improvements in their blood sugar control compared with those taking a placebo.
They then recruited several independent clinics to carry out a "proof-of-concept" trial involving several dozen people with Type 2 diabetes. The preliminary results, which were published in a peer-reviewed journal, were extremely encouraging. After 12 weeks, the people taking the probiotic formula saw meaningful improvements in their blood sugar control compared with those taking a placebo.
Most of these subjects were also taking metformin to control their blood sugar. While this pilot study did not test this, it certainly raises the question of whether it might be possible to reduce or even eliminate the medication altogether. At the very least, many of the subjects reported that the addition of the probiotic relieved some of the digestive discomfort that metformin frequently causes.
For that matter, could this probiotic therapy keep people with prediabetes from ever having to start on medication in the first place? And could the new population of beneficial bacteria be sustained without having to take the probiotic on a continual basis?
Dr. Cutliffe is currently designing and conducting research to further explore some of these questions. In the meantime, the formula used in the research (Pendulum Glucose Control) is available as an over-the-counter supplement. One problem is the cost: Although the company hopes that they'll eventually be able to lower the price as they scale up production (or even get it covered by insurance), the supplement currently costs $200 a month—far more than metformin.
In addition to the ongoing clinical research, the Mayo Clinic established a national registry where people taking this particular formula can anonymously share their data, including the results of their blood tests. Although certainly not a controlled clinical trial, this crowd-sourced information could add a lot to our understanding of how well this approach works in real-world situations (which is where we actually need it to work).
Probiotics are not a silver bullet
Whether you are taking metformin or a probiotic to help control your blood sugar, neither one is a silver bullet. And unfortunately, this is often an unintended consequence of pharmaceutical therapies. People taking statin drugs to control their cholesterol, for example, tend to be a lot less careful about their diets than those who don't. They may reason that as long as they have a drug to manage their cholesterol, their dietary choices don't matter. But of course, they do.
It would be a mistake to think that taking a probiotic means that you no longer have to worry about diet.
And Dr. Cutcliffe cautions that it would be a mistake to think that taking a probiotic means that you no longer have to worry about diet. Eating a healthier diet—specifically, eating more high-fiber foods—can change the composition of the microbiome and improve blood sugar control. And Cutcliffe reports that the combination of diet, exercise, and probiotic therapy produces better results more quickly than just taking the probiotic or just altering your diet.
Taking a targeted approach to probiotics
With all the focus on the microbiome, probiotic supplements have become one of the fastest-growing categories of supplements. And there is research to support the targeted use of probiotics, where the strains are carefully matched to the condition. Tailoring a probiotic supplement to address blood sugar regulation is a good example of this approach.
If you want to roll out the red carpet for the beneficial bacteria in your gut, put out a buffet for them.
Popping probiotics as a general preventive strategy, on the other hand, does not appear to make much sense. If your goal is simply to encourage healthy gut flora, a better strategy is to focus on the quality of your diet.
If you want to attract songbirds to your birdfeeder, you put out the kind of birdseed that your quarry favors. And if you want to roll out the red carpet for the beneficial bacteria in your gut, put out a buffet for them. In particular, include a variety of legumes, whole grains, nuts, seeds, fruits, and vegetables and take it easy on the red meat and refined sugar.