Paleo and diabetes is a popular topic, but it’s much harder to find information about prediabetes, which actually isn’t the same problem! And the distinction is definitely worth making: prediabetes doesn’t inevitably lead to the real thing. You can be diagnosed with prediabetes, but never progress to outright diabetes, and even reverse the process to get back to a healthy metabolism – here’s a look at what prediabetes is, and what kinds of diet and lifestyle interventions have been studied for it.
What Is Prediabetes (and How is it Different from Diabetes)?
To define a specific disease, doctors have to establish some kind of number-based criteria for judging who has it and who doesn’t. Either you’re sick or you’re healthy, and the question is just about the cutoff point between “normal” and “disease”?
For diabetes, there are a couple different cutoff points, where you’re officially “non-diabetic” on one side of the line, and officially “diabetic” on the other side of the line.
- HbA1C: this is a measure of long-term blood sugar control.
- Blood sugar test: this is a measure of how high your blood sugar is right now.
- Oral glucose tolerance test (OGTT): this is how well your body can respond to drinking a lot of sugar.
But human bodies don’t always work like that. You don’t jump from 0 to diabetic overnight; it’s a slow process of getting steadily sicker and sicker. For example, the cutoff for “diabetes” as measured by HbA1C is 6.5. But people with an HbA1C of 6.49 aren’t doing just fine because they’re technically on the non-diabetic side of the line! And it certainly doesn’t make sense to delay treatment and tell them they’re doing just fine until bam, suddenly, diabetes out of nowhere.
That’s where prediabetes comes in. Prediabetes is defined as blood sugar that are too high to be healthy, but not high enough to meet the cutoff for diabetes. To put some numbers on it:
- HbA1C: Up to 5.7 is normal; 5.7-6.4 is pre-diabetic; 6.5 and above is diabetic.
- Fasting blood sugar test: Up to 100 mg/dL is normal; 100-125 mg/dL is prediabetic; 126 or above is diabetic.
- OGTT: Less than 140 is normal; 140-199 is prediabetic; 200 is diabetic.
“Prediabetes” is a way to say “something’s not right, even though it’s not actually full-blown diabetes yet.” Just like full-blown diabetes, prediabetes is inflammatory, associated with eye and kidney damage, and linked to cardiovascular problems. It’s more common in people who smoke, drink, don’t work out, or already have hypertension, blood lipid problems, and obesity.
Not all people with prediabetes go on to become diabetics, and many people develop diabetes without ever being officially “prediabetic” (Type 1 and gestational diabetes come to mind).
Lifestyle Interventions for Prediabetes
The question in lifestyle interventions for prediabetes is simple: how can you stop prediabetes from developing into full-blown diabetes, and preferably return to normal blood sugar readings? The really sad part about those interventions how many people look at them as just a way to delay the inevitable. It’s all about putting off diabetes for a few more years – what about normalizing blood sugar and not progressing to diabetes in the first place? Paleo is about optimal health, not just “being less sick:” why assume that delaying diabetes is the best we can do?
Ideally, interventions for prediabetes wouldn't just put off diabetes; they'd prevent it. And ideally, you'd research this out by taking people with prediabetes, having them eat different diets, and seeing which ones prevent full-blown diabetes down the line.
Unfortunately, there aren’t a lot of long-term studies like that. Most of the literature is either short-term (we gave subjects this food, and it reduced their blood sugar…after one meal!) or in people with outright diabetes. But what we have suggests that healthy diet and lifestyle interventions can be very effective – much more so than drugs. Here’s a look at some interesting studies.
Diet and Prediabetes
The standard dietary recommendations for prediabetes are so clearly a product of the low-fat diet age. The typical advice goes something like this: lose weight by calorie-counting and restricting fat, and start exercising to burn more calories. Calorie-counting is a painful and unsustainable way to diet, exercising to burn calories doesn’t work, and fat restriction is downright unhealthy: it’s not surprising that this advice doesn’t exactly produce great results!
What’s more, there’s increasing evidence that when they do work, diet and exercise help regardless of weight loss. Weight-loss diets for prediabetes don’t work because they reduce calories; they work because people start eating more healthy foods (and/or stop eating unhealthy foods). This implies that dietary interventions should focus on health, not on calorie-counting for weight loss, and also that there’s more to life than calories.
Since this is prediabetes, the first place to look is probably carbs. It’s well-known that carb-restricted diets are helpful for diabetics, and some studies have also found that they’re useful for normalizing blood sugar in prediabetics. For example, this study found that a low-carb diet was significantly more effective than a control diet for normalizing blood sugar levels, reducing insulin resistance, and preventing progression to diabetes (0% of the low-carb subjects became actually diabetic, compared to 14% of the control subjects). “Low-carb” in this case meant a maximum of 120 grams of carbs, which is equivalent to just over 1 pound of sweet potatoes per day.
What if you go even lower than that? This study on diabetics and prediabetics found that a ketogenic diet was more effective than a moderate-carb, low-fat, low-calorie diet for improving HbA1C, getting people off medications, and losing weight.
Moving on from carbs, this article also makes the case for higher protein intake in people with prediabetes, particularly to help maintain muscle mass during weight loss.
If you combine all these recommendations for diet and weight loss, you get something that looks a lot like the typical Paleo meal: a big pile of non-starchy vegetables, generous helpings of animal foods, optionally some starchy carbs, and an overall setup that lets most people lose weight sustainably without going crazy.
Exercise and Other Lifestyle Interventions
Exercise is also commonly recommended to people with prediabetes, and it does seem to be helpful, but not because it makes you lose weight by burning calories. Instead, it's about the hormones: several studies have shown that exercise can improve insulin sensitivity and glucose tolerance, even if it’s as gentle as walking.
As for other interventions, there’s plenty of evidence that stress management, getting enough sleep, and fighting inflammation can help with insulin sensitivity and blood sugar management in general, even if there aren’t any studies specifically examining their effect on prediabetes in particular.
Summing it Up
Prediabetes shouldn’t be a life sentence or a diagnosis of “inevitable” diabetes progression down the line. It’s a serious issue, but it’s not a reason to throw up your hands and start stockpiling metformin.
Diet and exercise are the two most commonly recommended interventions for prediabetes. Typically, these are aimed at weight loss, but actually it looks like the weight loss might not be the reason for improvement – what really helps is normalizing insulin and blood glucose levels through diet and exercise interventions targeted at that. There are some studies suggesting that a low-carb diet might be superior to a typical calorie-reduced diet, and exercise is always a great way to improve insulin sensitivity and blood sugar control, even if it’s just walking.
It’s very easy to do all those things with Paleo: a basic out-of-the-box template even without any modifications will get you most of the way there.
Unfortunately, there aren’t a lot of studies on prediabetes and other factors like sleep, stress, and specific nutrients – diabetes gets all the press, and prediabetes tends to be ignored. But we know these things help with blood sugar control in general, so it’s a good bet that they could be helpful. Hopefully soon we’ll start seeing more people interested in preventing diabetes, instead of just treating it once it’s already established, and some more research clarifying specifically what dietary interventions are helpful for prediabetes in particular.