Goodbye, carbs. You might find yourself seriously missing some of your favorite foods when you switch to a ketogenic diet. Even though you know the benefits far outweigh the sacrifices, it can be difficult at first to eliminate some of the foods you’ve been eating your entire life.
But when it really comes down to it, how many carbs should you eat on a ketogenic diet? None at all? Less than 10 grams? Half than what you normally do? The answers vary and depend on a number of factors. But if you’re serious about keto, you need to know exactly how many carbs you should be eating. Luckily, we’re here to help.
Why Are Carbs Limited on Keto?
Poor carbs. They have such a bad rap, especially when it comes to keto. But it’s for a good reason. If you eat carbs, you can never enter ketosis, which is the main goal of eating a ketogenic diet. When you’re in ketosis, you experience tremendous weight loss, mental clarity, increased energy, and an overall feeling of wellness. But this can only be achieved by eating minimal carbs 
. Here’s why.
Our bodies traditionally rely on glucose for energy. Our bodies get glucose through carbohydrates, which are the bulk of most people’s diets. You might be familiar with feeling a sudden surge of energy after eating followed by a crash not long after. This is normal with carbs and leads us to excess snacking and larger portions. But if we eliminate carbs from our diet, our bodies have to find energy from a different source. As it eliminates glucose stores, the body turns to fat for energy. Burning fat is a natural metabolic state that provides the benefits previously mentioned .
The good news is that ketosis isn’t difficult to achieve. The bad news is that all it takes is one carb-filled meal to throw your body out of ketosis. This is why they have to be extremely limited while eating a ketogenic diet.
How Do You Measure Carbs for Keto?
In most cases, we measure carbs in grams. The next time you go to eat something, take a look at the nutritional value panel. You’ll notice a few things about the carb portion.
The first line will tell you the total number of grams of carbs in a serving size. The next line will mention how many grams of fiber there are in a serving. In keto, you’ll subtract the number of fiber grams from the overall carb grams. The number left is the net carbs and is the number you should be worried about.
For example, a product that contains 10 grams of total carbs and 5 grams of fiber would come out to 5 net grams of carbs. So, for every serving, you need to add 5 grams of carbs to your daily intake, making sure you don’t exceed your allowance.
How Many Grams Should I Start With on Keto?
It may take some time to find the ideal number of carbs for you as an individual on keto. As your body switches from using glucose to fat for energy, you could find yourself needing to keep your carb intake as low as 20 grams and as high (though rarely) as 100 grams.
There are a couple different ways you can go about finding out what your magic number is (the easy way at least – we have a more scientific method for you later).
At first, you can start with a higher number of carbs. You should only try this method if you know you’re not in ketosis yet. Start around 50 net grams of carbs per day and then slowly reduce this number by about 5 new grams per week. You should routinely test for ketones with both of these methods. If you’re not sure how to test for ketones, we have a great guide for you here.
This is an easy method to try but it could take several weeks for you to find your perfect number. Also, you need to keep the same carb count for a week as it could take a few days for your body to eliminate glycogen stores. Be patient and consistent.
The second method is the opposite of the first. You’ll start with a very low number of carbs (less than 20 grams per day) so that you quickly enter ketosis. Once you know you’re in ketosis for a few days, start slowly adding carbs to your daily limit every week. You can do the same as for the other method, or 5 grams per week, or go with a smaller number for a more specific daily limit. You would be surprised at what an extra gram or two of carbs can do to your ketosis stage.
Once you start to notice your ketone level lessening or completely disappear, you know you’ve gone over your daily carb limit. This method is usually more reliable than the first and faster as well. If you can take the drastic cut in carbs, we recommend this method.
How to Figure Out You Macros
Calculating your macros is the best way to determine how many carbs you should be taking in a day. Macros is short for macronutrients, which are the three components your diet is comprised of – fat, protein, and carbs. There are a few different things you’ll need to know before you can figure out your individual macros . These include:
- Body fat percentage
- Activity level
Don’t’ estimate or round any of these numbers (especially your weight). The more precise your answers are, the more accurate your macros will be. We have a much more detailed guide here that will walk you through calculating your macros. But for now, here are the basics laid out for you.
Start by determining how many calories you need a day. You’ll need your weight (W), height (H), and age (A). Then use the following formulas.
- Men: 66 + (6.23 x W) + (12.7 x H) – (6.8 x A) = BMR
- Women: 655 + (4.35 x W) + (4.7 x H) – (4.7 x A) = BMR
Now that you have your BMR, or XXX, figure out how active you are. Here are your options.
- Primarily sedentary – 1.2
- Sedentary – 1.375
- Moderate – 1.55
- Active – 1.725
- Extremely active – 1.9
Multiply your BMR by your activity number. This is your daily calorie intake needs. Now it’s time to figure out your macros. First, we need to know how many calories are in a gram of each macro.
- 1 gram of protein – 4 calories
- 1 gram of carbohydrates = 4 calories
- 1 gram of fat = 9 calories
The basic ketogenic diet looks like this.
- 75% fat
- 20% protein
- 5% carbs
So now it’s just a matter of doing the math based on your individual calorie needs. Here are a few more instructions.
- To figure out fat grams, multiply calorie intake by 0.75. Divide this by 9.
- To figure out protein grams, multiply calorie intake by 0.20. Divide by 4.
- To figure out carbohydrate grams, multiply calorie intake by 0.05. Divide by 4.
So, if your daily calorie needs came out to the recommended 2,000 a day, your macros would look like this.
- 166 grams of fat
- 100 grams of protein
- 25 grams of carbs
Signs You Need to Cut Back on Carbs
If you’re new to keto, one of the best things you can do is learn from the mistakes of others. We can’t tell you how many stories we hear of people thinking they were in ketosis for weeks or even months, only to find out they’ve been holding themselves back and limiting the benefits of ketosis. So even if these signs seem obvious or too simple, pay attention. Your body will always tell you if you’re eating too many carbs.
You’re not losing weight
Though not everyone does, most start a keto diet to lose weight. Once they enter ketosis, weight loss is rapid and noticeable. Even though the beginning is typically bloating and water weight, fat loss will occur with proper ketosis. So, if you’ve been following a ketogenic diet for several weeks and haven’t noticed any weight loss (or worse, you’ve noticed weight gain), then it’s time to reevaluate your macros. Chances are, you’re taking in way too many carbs .
Your energy levels are inconsistent
When you’re in ketosis, your energy levels should sky rocket. Not only should you have more energy, but it should remain consistent throughout the day without the crashes you may have been used to on a mainly carbohydrate diet. If you notice that you have a day or two of great energy followed by days of fatigue or inconsistent energy, you could be going in and out of ketosis. It’s time to reevaluate your carb intake.
Your testing levels are inconsistent
Until you understand exactly how your body acts in ketosis, you should routinely test for ketones. There are a few ways you can do this. You can test with either blood, urine, or your breath. There are pros and cons to each, but we recommend blood as the most accurate test method. But if you need a more affordable method, urine strips are affordable. If you choose to measure ketones through your urine, we recommend using a back-up testing method to ensure your levels are consistent. If you’re noticing inconsistent ketone levels, it’s time to take a closer look at your carb intake.
Using Exogeneous Ketones to Combat Carbs
There’s one trick you can use to speed up your entrance into ketosis while cutting back on carbs. It can also be used if you make a mistake and end up eating more carbs in a day then you should have. This magical tool is known as exogeneous ketones. When you’re in ketosis, your body produces ketones. But ketones can be synthetically produced and consumed in a supplement form, essentially tricking your body into thinking it’s already in ketosis .
There are a few things you should know before you start taking exogeneous ketones. First, they won’t work if you’re eating too many carbs on a regular basis. While you’ll still have ketones present in your body, you won’t experience any of the benefits of ketosis because your glucose levels will still be so high.
But if you’ve been following a ketogenic diet for a bit and, whether on purpose or on accident, went over your daily carb intake, you can take exogeneous ketones to help speed up the elimination of glucose and get back into ketosis. This shouldn’t be done on a daily basis though. It’s more of an emergency solution.
You can also use exogeneous ketones if you’re starting to enter ketosis and finding yourself suffering from the keto flu. Sometimes, entering ketosis can leave you feeling fatigued, achy, and irritable. This is normal and part of the transition. But taking exogenous ketones can lessen the severity of the symptoms and their duration.
You can’t rely on exogeneous ketones to save you from carbs every time. But they can save you when you overdo it or when you’re first trying to enter ketosis. You’ll feel better and reach your goal faster with exogeneous ketones. Some prefer to do it on their own but if you want a little help, these supplements are the perfect solution.
Tips for Cutting Carbs on Keto
Need to cut back on those carbs even more than you originally thought? We know how hard it can be. That’s why we’ve put together some of our top tips for cutting back on carbs. With a little creativity and plenty of determination, you can stay within your macros and reach deeper levels of ketosis.
Stick with water
There are so many temptations when it comes to choosing a beverage. But when it comes to nutritional value, drinks rarely offer anything positive, even if they’re labeled as fruit-filled or all natural.
Drinks can have a ton of additional sugar in them, which can throw off your macros, and typically sugar-filled means carb heavy. One 12-ounce glass of sweetened ice tea can have an astonishing 36 grams of carbs.
If you’re struggling to stick with only water, try adding a few drops of flavoring. You can find keto-approved drops that can magically change your glass of water to tropical punch or blackberry lemonade. Just make sure you check the nutritional value and ingredients.
Watch keto-approved labels
Unfortunately, the food industry isn’t on our side. Even products labeled as keto-approved can have hidden ingredients, including carbs. It’s always in your best interest to choose foods Mother Nature provided instead of something mass-produced in a factory. So, don’t fall for marketing hype. You want to really make sure that the products marked as low-carb are really that.
Substitute everywhere you can
There are plenty of ways to still get your fill for your favorite foods without eating carbs. For example, cauliflower is a great carb substitute. You can make cauliflower pizza crust that will allow you to enjoy your favorite toppings with the family. You can also roast or mash cauliflower for a potato substitute. If you’re really craving bread, there are low-carb options you can choose from but just be careful as they could still be higher than your daily allowance. For a healthy low-carb taco shell substitute, wrap substitute, or sub sandwich substitute, try large pieces of Romaine lettuce instead.
When it comes to milk, try coconut milk or unsweetened almond or soy milk for a healthier option. Dying for some pasta? There are low-carb options available. Our favorite is zucchini noodles. If you’re a little creative and willing to try something different, there’s a substitute out there that can help you fulfill a craving without throwing your body out of ketosis.
Recalculate your macros periodically
Remember those numbers you needed to know when calculating your macros? Those numbers will change with time, like your weight, age, and physical activity level. Therefore, you’ll want to periodically recalculate your macros, especially when you know something has drastically changed. The right number of carbs for you today will probably not be accurate in six months’ time.
If you feel like you’ve cut back your carbs as much as possible but you’re still struggling to reach ketosis, it might be time to schedule an appointment with your doctor. Make sure they’re understand the ketogenic diet . Together, you should be able to figure out what’s preventing you from going into ketosis, whether it’s due to an innocent mistake or a health concern.
The ketogenic diet isn’t for everyone. It takes plenty of determination to keep up with such a strict diet. The good news is that it’s not impossible and as the diet gains more attention, there are more resources and support to stick with it. If the benefits of ketosis are worth it to you, you’ll be able to find the perfect combination of macros and successfully enter ketosis with time and persistence.
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