Updated: Aug 25
I’m not a fan of trendy diets. And there have been some crazy ones over the years — the cabbage soup diet, the human growth hormone diet, and the baby food diet (and yes, people really did diet by eating baby food).
Most of these diet trends are geared at fast — and honestly unsafe — weight loss. And I don’t recommend any of them.
But that doesn’t mean that following a particular eating style is a bad idea. We’ve come to associate diets with weight loss. And yes, many of them do make those promises. But if you’re struggling with a health condition like prediabetes, there are some eating styles that can genuinely help you balance your blood sugar and improve your health. In fact, there are dietary changes you can make that can actually reverse your prediabetes diagnosis!
Two of the most popular approaches to balancing blood sugar through food are the low carb diet and the ketogenic (or keto) diet.
And while these two diets have some things in common, they are not the same.
What do low-carb and keto have in common?
Both of these eating styles include reducing your carbohydrate intake. As we’ve talked about before, reducing your carbs can make a big difference in your blood sugar balance.
Carbs affect blood sugar more than protein or fat do. That’s because your body quickly breaks down carbohydrates — especially highly processed ones — into simple sugars that flood your bloodstream. When all this glucose enters your blood, your blood sugar numbers spike. This can create a state of emergency in the body.
When your blood sugar is too high, the body releases extra insulin to try to shuttle the glucose into your cells and get it out of the blood. When this happens quickly, your blood sugar can actually dip too low.
So if you’re prediabetic — meaning your body has started struggling to keep your blood sugar balanced — eating a lot of carbs can cause your blood sugar pattern to hit drastic highs and lows. And this is not what we want. A healthy blood sugar pattern should be more gently rolling than spiky.
Both the low carb diet and the keto diet are low in carbs. The differences come in how low you go, and what you replace those carbs with.
What is the low-carb diet?
When you eat a low-carb diet, you are lowering your carb intake. You don’t stop eating carbs completely. But you eat fewer. You reduce your carbs (foods like grains, rice, sugar, and starchy veggies) to about 10-30% of your caloric intake.
According to the The Nutritional Examination Survey (NHANES), most Americans get about 48% of their calories from carbohydrates. So the low-carb diet may mean cutting your carb intake by as much as half. For example, someone who consumes 2,000 calories per day would eat between 50 and 150 grams of carbohydrates on the low-carb diet.
Is the low-carb diet good for you?
As with most things in life, the low-carb diet has both pros and cons.
Low-Carb Diet Pros
✔ May help you lose weight — especially at first.
✔ Can help reduce your appetite — protein and fat tend to be more filling than carbs.
✔ You’re more likely to lose belly fat — which is beneficial to your health.
✔ Eating low-carb can improve your heart health markers like LDL & HDL cholesterol, triglycerides, and blood pressure.
✔ Helps lower both blood sugar and insulin. And this great news if you’re prediabetic.
✔ Combats metabolic syndrome by improving the symptoms — also great news for people who struggle with blood sugar balance.
✔ The low-carb diet is pretty sustainable in the long term. You do have to make dietary changes, but they are fairly reasonable and possible to maintain for many people.
✔ You have to pay attention to what you eat and turn down treats. This also requires planning ahead.
✔ You may develop constipation, especially at first while your body adjusts.
✔ It’s possible to develop micronutrient deficiencies, but not guaranteed. Taking a whole-food approach and including lots of low-carb veggies and even some fruits will combat this.
✔ Even though fruit is a generally healthy choice, you’ll need to limit your fruits on a low-carb diet.
What’s the difference between low-carb and keto?
The ketogenic diet — or keto — is a more restrictive approach to low-carb eating. On a low-carb diet you may reduce your carbs to the 50-150 grams range. But with keto you cut your carbs down to fewer than 50 grams per day. To put that in perspective, a honeycrisp apple has 34 grams of carbs.
But eating fewer carbs isn’t the only difference between low-carb and keto. But before we get into the other main difference, let’s talk about what the keto diet actually does.
What is the keto diet?
When you eat keto, you are putting your body into a state of ketosis. When we eat, our body burns the food we eat as fuel. If you eat a high-carb diet, your body will burn the resulting glucose (sugar) as fuel.
When you’re in ketosis though, you aren’t eating enough carbs to create much glucose so your body has to turn to another fuel source — fat (ketones). When you’re eating a keto diet, it trains your body to burn fat for fuel instead of sugar.
And that brings us to the other main difference between low-carb and keto: fat consumption. When you eat low carb, you replace the missing carbohydrates with protein and some fat. Protein is great because it keeps you full, helps build and maintain muscle, and more.
But if you eat too much protein, it can knock you out of ketosis. So if you’re on the keto diet, you limit both carbohydrates AND protein. What’s left? Fat. When you’re on keto, you eat lots of fat. I’m not talking about deep-fried anything. But you can include foods like healthy oils, avocados, nuts & seeds, full-fat dairy (if you tolerate it), and butter.
And just like the low-carb diet, there are pros and cons to eating keto.
Keto Diet Pros
✔ Improves insulin sensitivity — which is great if you have blood sugar issues. Most people who are prediabetic have insulin resistance (the opposite of insulin sensitivity).
✔ Can improve some heart health markers like cholesterol and triglycerides.
✔ May reduce your appetite.
✔ May help with managing certain conditions like epilepsy.
Keto Diet Cons
✔ Constipation is common because when you reduce carbs because it’s easy to miss out on dietary fiber.
✔ Severe food restrictions. If you want to stay in ketosis, you have to severely restrict your carbs, giving up a lot of foods including fruits and most sweet treats.
✔ Because it is so restrictive, it’s a difficult eating style to maintain long-term.
✔ There aren’t a lot of long-term studies yet so we don’t know how keto will affect people over time.
✔It may discourage metabolic flexibility- the ability to adapt to changes in metabolic demand.
✔ The dreaded keto flu.
What is keto flu?
When you are switching your body over from burning sugar to burning ketones, there can be some side effects. Because the symptoms feel flu-like, people started calling this phenomenon the keto flu. It’s not an actual illness, but rather a potentially difficult adjustment period.
Keto flu symptoms include:
The good news is that keto flu only lasts about a week. And there are things you can do to improve it. If you are planning on taking on the keto diet, you don’t have to do it all at once. You can start with a low-carb diet and gradually reduce your carb intake over time. This will likely make the transition less uncomfortable.
Keto can impact your electrolyte balance. This is the balance of minerals like sodium and potassium in your body. You can add these minerals back in by adding a sprinkle of good quality sea salt and lemon to your water or by taking an electrolyte supplement. Just make sure to check with your practitioner to make sure you’re choosing the right minerals for you.
Which diet is best for you?
We are all unique individuals. And what works well for one person might be a disaster for the next. We all react differently to carbohydrates. And the right amount for one person might be too much — or too little — for another. If you’re making a change to your diet, especially for therapeutic reasons like lowering blood sugar, I highly recommend you work with a qualified practitioner.
Did you know that a steam sauna can improve blood sugar?
Yes, that’s right! And there are many other ways to improve blood sugar. Addressing prediabetes doesn’t have to be hard. Ready to improve your blood sugar without changing your diet? Sign up for my FREE mini course, 10 Ways to Improve Blood Sugar Without Changing Your Diet. It’s a free email course, and it’s a fast and easy way to learn 10 impactful tips to begin balancing your blood sugar TODAY! Learn more