Here's what you need to know about how the low-carb diet may help control your blood sugar.

By Ashley Mateo
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While many stories you read about the keto diet are about incredible weight loss transformations, keto does have some other health benefits. (And we aren't talking about the pseudo-science claims out there.) Turns out, the high-fat, low-carb ketogenic diet can potentially help with the symptoms of Type 2 diabetes.

First, a refresher: The goal of the keto diet is to put the body into the state of ketosis, where it uses fat for energy instead of carbs. That's why keto meals are broken down into a ratio of 70 or 80 percent fat, 20 percent protein, and just about 5 percent carbohydrates.

Diabetes is a disease in which your blood glucose (or blood sugar) levels are too high and your body doesn't make or adequately use insulin, which is responsible for regulating your blood sugar. One of the reasons someone's blood sugar can be too high is a high carb intake, says Ken Berry, M.D., author of Lies My Doctor Told Me: Medical Myths That Can Harm Your Health.

So, How Does Keto for Diabetes Work?

The keto diet is actually helpful in managing diabetes for one major reason: It lowers your carb intake. "Carbohydrate is the macronutrient primarily responsible for drastic increases in blood glucose," explains Robert Santos­ Prowse, clinical dietitian and author of The Cyclical Ketogenic Diet. Bottom line: Carbs are broken down into sugar in your body.

The issue revolves around the effect of carbohydrates on your body's production of insulin, says Ethan Weiss, M.D., an associate professor at the Cardiovascular Research Institute at the University of California, San Francisco. "To utilize glucose as a fuel, you need insulin, which is made by the pancreas," explains Dr. Weiss. When you have more sugar in your blood than your body needs, insulin directs cells to convert glucose to fat for long-term storage; high insulin levels also prevents fat from being broken down for energy.

On a keto diet, when you replace carbs (AKA sugars) with fats, that need for insulin is dramatically reduced, says Weiss. Because of that, "the body becomes much more efficient at using it and, therefore, it makes much less. That means that the body handles carbohydrates better and has much more stable glucose levels"—a good thing for weight and diabetes management, which go hand in hand.

In fact, recent science found that type 2 diabetes can actually be reversed in some adults by following an intensive weight management program (hello, keto). And the evidence of the effects carb restriction on diabetes is strong enough that in 2018, the American Diabetes Association added low-carbohydrate diets as a viable treatment for diabetes.

But Keto Is High-Fat—Does That Matter for Diabetics?

Weight gain is definitely linked to a higher risk of type 2 diabetes so it might sound illogical that a high-fat diet could actually help manage the disease. But, reminder: Fat isn't necessarily a bad word. "Fat makes you feel more full than carbohydrates do," says Santos Prowse. "People following a ketogenic diet tend to eat fewer total calories because the foods they are eating are so rich and satisfying." That's a major reason the keto diet is so effective for weight loss.

And then, we're back to insulin. "Insulin is one of the primary hormones involved with body fat creation and storage," he explains. "Eating a very low-carbohydrate diet reduces the amount of insulin in the blood and therefore reduces the amount of fat storage taking place."

Remember, the keto diet isn't a free pass to eat just any high-fat foods. You want to focus on heart-healthy fats in keto-approved foods like avocados, olive oil, salmon, nuts and nut butters, and seeds. (Related: Can You Eat Peanut Butter On the Keto Diet?)

Are There Any Drawbacks to Usng the Keto Diet for Diabetes?

Look, no one said the keto diet was easy. Cutting carbs back to just five percent of your daily intake can be seriously tough. And research in The Lancet shows that restrictive diets like keto could actually shorten your lifespan. So it's not something you should just casually jump into, especially if you're looking to manage a disease like diabetes.

"The main drawback of a ketogenic diet is that it requires much more intentionality than any other type of diet," says Santos Prowse. "It needs to be well-formulated to ensure your nutrient needs are being met and it requires that you pay close attention to what you are eating." For example, when you're in ketosis, your kidneys shed electrolytes like sodium, potassium, and magnesium at a higher rate than normal, he adds. Since those minerals are crucial in transmitting signals to your muscles and nerves, it's important to make sure you are getting enough of them in your diet.

It's also not the most sustainable diet. While you can shed five to 10 percent of your starting weight within the first six months on a restrictive diet like keto, research has shown that at least one- to two-thirds of people on those diets will regain more weight than they lost within four or five years. (Related: Why You Should Give Up Restrictive Dieting Once and for All)

The best thing you can do if you're interested in trying keto, for diabetes or otherwise, is to work closely with a physician and nutritionist. If you are diabetic, you may need to make adjustments to your medications, and your doctor should be monitoring your ketone levels and your blood glucose so you can avoid serious complications like diabetic ketoacidosis, which can occur when you have dangerously high levels of ketones and blood sugar that makes your blood too acidic and can affect your internal organs.

So, what's the verdict on the keto diet for diabetes? It can be a solution—but only if you do your research and do it right.