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The humble tomato appears in countless classic dishes like spaghetti and pizza. And since you don’t think of tomatoes as being high-sugar vegetables, you might naturally assume that tomato sauce is low enough in carbs to fit into the keto diet.
Of course, if you’re serious about keto, you know that it’s important to double-check the carbohydrate content of just about everything — even canned tomatoes! So is tomato sauce keto-friendly? Let’s find out.
Table of Contents
- What’s in Tomato Sauce?
- Are Tomatoes Keto Approved?
- Is Tomato Sauce Keto?
- Where Do All the Carbs in Tomato Sauce Come From?
- Does Tomato Sauce Have Any Other Health Benefits?
- How to Make Your Own Keto Tomato Sauce
- What Goes With Keto Tomato Sauce?
- Recipes: How to Use Keto Tomato Sauce
- Breathe New Life Into Your Keto Diet!
What’s in Tomato Sauce?
Before we start looking at pasta sauce to see if it will fit into your keto diet, it’s important to understand what’s in it. Obviously, tomatoes are the main ingredient. Most sauces (and especially low-carb tomato sauce options) also have extra virgin olive oil. The oil imparts a richness to the flavor and helps create a smoother consistency. And if your sauce contains basil, oregano, or other herbs, olive oil pairs beautifully with those flavors.
Of course, these are the baseline ingredients. Each sauce varies somewhat in terms of spice, but most have black pepper and salt. Most also include some type of herbs. Basil and oregano are common, and some sauces with a little heat include some red pepper flakes as well. Garlic powder and/or onion powder are common add-ins, too.
If you like extra veggies in your sauce, you might be interested in adding mushrooms, garlic, onions, or chopped bell peppers. For extra flavor, you can saute these vegetables in butter before stirring them into the sauce.
And as you’ve likely seen, lots of sauces also have some cheese stirred in. Parmesan and Romano are two popular choices, though you can really put in any cheese you want. Don’t be afraid to experiment; there are seemingly endless ingredients you can combine to really make your low-carb tomato sauce your own.
Are Tomatoes Keto Approved?
Nothing beats the taste of fresh tomatoes on a salad, burger, etc. But can you eat tomatoes on a keto diet?
The answer here is yes. Provided you don’t eat a very large serving size, fresh tomatoes (or canned tomatoes) can be a healthy part of a well-rounded keto diet or otherwise low-carb diet.
Tomatoes come in various serving sizes. But a common serving size is one medium whole tomato. Medium fresh tomatoes have 22 calories each. There are 4.82 carbs per serving and 1.5 grams of fiber. That means there are 3.32 net carbs per serving.
Of course, your net carb budget will vary depending on the exact keto diet you’re following. But generally speaking, many people on keto set their allowed net carbs per day to about 25-50. If you’re getting ready to start keto (or an otherwise low-carb diet), this video will help you decide how many of each macronutrient you need per day. Generally speaking, keto diet plans are low in carbs, high in fat, and moderate in protein.
Is Tomato Sauce Keto?
You now know that the low net carb count makes tomatoes keto-friendly (provided you don’t eat a massive amount). But can you eat tomato sauce on keto?
That all depends on the individual sauce. Store-bought jarred sauce varies widely in terms of carb count. You might wonder why; after all, spaghetti sauce and marinara sauce are made largely of tomatoes, right?
This is true, but a surprising number of tomato sauce brands have a good bit of added sugar. And thanks to that fact, the net carbs in tomato sauce vary pretty widely from brand to brand.
On the lower end, some tomato sauce brands have about 2g of net carbs per every 100-gram serving. On the higher end, some sauces have as much as 10g net carbs. The bottom line is that lots of store-bought sauces are low-carb spaghetti sauces. But just make sure you check the labels!
Of course, some companies now offer low-carb marinara sauce options that are often marketed as keto tomato sauce. These sauces generally do not have added sugar, or they may use a carb-free sweetener. And since keto is generally a high-fat diet, many of these sauces also contain more olive oil than your average tomato sauce.
In a bit, we’ll show you how to make easy keto marinara sauce. Making your own keto tomato sauce does have its advantages: you can adjust the fat content by adding olive oil and/or butter, and you can also add your favorite spices. The healthy recipes we’ve included are also very easy to make.
Where Do All the Carbs in Tomato Sauce Come From?
We now know that the answer to “is tomato sauce keto-approved” is “sometimes.” But most of us don’t think of pasta sauce or tomato sauce as being high in sugar. So where do the carbs come from? Generally, there are two kinds of sugars in tomato sauce (and most other foods): natural sugar and added sugar.
As we noted above, tomatoes themselves have a bit of natural sugar, though not as much as sweeter fruits. Whole tomatoes (especially those with the skin still on) have some fiber that reduces the net carbs in each serving.
A surprising number of sauces have sugar added. That might seem unusual in a savory food. But the reason why is simple. As you know, tomatoes are a fairly acidic food, so plain tomato paste and other canned tomatoes are similarly acidic. The sugar added helps to neutralize some of the acid, giving the marinara sauce a more balanced taste. That said, some brands seem to go a little overboard on the added sugar. But you can still find a low-carb tomato sauce that tastes amazing and has no added sugar!
As a side note, if you often find pasta sauce a little too acidic but don’t want to add sugar, you might be interested in sauces made with yellow or orange tomatoes. These varieties tend to be a little less acidic, but they still have plenty of flavor! It can be tough to find low-carb spaghetti sauce made with yellow or orange tomatoes, but if you can’t find any at all, you can make your own pasta sauce.
Does Tomato Sauce Have Any Other Health Benefits?
Pasta sauce and marinara sauce can certainly fit into a keto diet. But can they add anything positive? Before you make your own perfect keto tomato sauce, you might want to learn a bit about some of the health benefits the tomatoes in the spaghetti sauce have to offer.
- They’re high in lycopene. This is an antioxidant that is responsible for coloring the tomatoes as well as protecting them from sun damage. It does the same in people. Like other antioxidants, it can reduce your risk of some kinds of cancers while also slowing the effects of aging.
- They may help protect your eyes. The blue light emitted by screens can cause some serious eye strain. But tomatoes contain zeaxanthin and lutein, two substances that seem to have a protective effect on your eyes. They may also offer some protection against macular degeneration caused by age, one of the leading causes of blindness.
- They’re high in vitamin C. Just one medium tomato has roughly 40% of the recommended daily value of vitamin C. As you know, vitamin C is essential for many crucial functions: it supports immunity and the absorption of iron, among other things.
- They support digestive health. Tomatoes are fairly high in fiber, and fiber is a key part of helping your digestive system function smoothly.
- They are rich in vitamin A and vitamin K. Vitamin A just might be the most important vitamin when it comes to skin health, though it also supports your vision and immune system. Vitamin K isn’t quite as talked about as some other vitamins, but it is especially helpful when it comes to bones health.
- They are rich in potassium. Potassium is a very important electrolyte that plays a role in a whole host of bodily processes. It helps support heart function, blood pressure, fluid balance, and muscle contractions.
- They may help manage type II diabetes. This potential benefit has only recently been investigated. One study found that eating cooked tomatoes daily caused a reduction in lipid peroxidation, a process involving fats being attacked by free radicals. Lipid peroxidation increases your risk of heart disease. That’s especially important, as those with type II already have a doubled risk of heart attack and stroke.
As you can see, the tomatoes in spaghetti sauce offer an impressive array of benefits. But the olive oil put into it also offers some benefits. If you put olive oil in your low carb spaghetti sauce, you can reap some of these health benefits:
- It’s rich in healthy fats. The keto diet is high in fat, and it’s important to make sure most of these fats are healthy. Unlike saturated fat, monounsaturated fat (like the main fat in olive oil) has been linked to a reduction in inflammation and even a reduction in risk for some kinds of cancer.
- It’s high in antioxidants. As we mentioned above with tomatoes, antioxidants are especially helpful when it comes to reducing cancer risk. That’s because they help to slow or stop cell damage from free radicals. These are unstable molecules that cause damage over time.
- It has great anti-inflammatory properties. Several nutrients in olive oil, especially the antioxidants, work to reduce inflammation. That isn’t just good for injuries; many experts now believe that chronic inflammation is linked to serious illnesses like type II diabetes, cancer, and heart disease.
As you can see, the ingredients in keto marinara sauce (or any marinara sauce) have some surprising health benefits. But just like with anything else, be sure to consume low-carb tomato sauce in moderation — too much of any single food is not generally a good thing, especially on a keto diet!
How to Make Your Own Keto Tomato Sauce
So is red sauce keto? Not often. But if you want to make some keto-friendly recipes, the good news is that you can make your own keto tomato sauce. And it’s a lot easier than you think! Here’s what you need to make your own low carb marinara sauce:
- Canned crushed tomatoes — San Marzano tomatoes are especially good if you can find them! You can also get canned whole tomatoes and use a potato masher or immersion blender to get a smoother consistency. Peeled tomatoes will give you the smoothest sauce.
- Extra virgin olive oil
- 2-3 cloves of garlic (you could also use garlic powder and/or onion powder if you prefer)
- Oregano — fresh is ideal but dried is fine
As a side note, if you prefer fresh tomatoes over canned tomatoes, you can use them instead. Plum tomatoes are a good size to choose.
If you like some extra flavor in your sauce, you can add in some extra ingredients like red pepper flakes, fresh basil, or butter.
As you can see, we haven’t specified exactly how much of each ingredient you need. That’s because different people prefer different consistencies, levels of spice, etc. You can sample the tomato sauce throughout the cooking process and adjust ingredient levels to taste. Here’s how to make it:
1. Heat up a fairly large amount of olive oil in a saucepan — at least a few tablespoons.
2. Finely chop the garlic cloves and add them. Then add the tomatoes.
3. Add a dash of oregano and pinch of salt. Check the flavor and add more as needed. You can also add in other spices at this point if you want.
4. Simmer the sauce for about 10 minutes. If you want it to be thicker (like for pizza sauce), cook a little longer to evaporate more water.
When you make this sauce, you can partially mash the chopped tomatoes for a chunky sauce or opt for a little more time in an immersion blender for a smooth sauce. Don’t be afraid to experiment and see which option makes the best low-carb tomato sauce!
Once you’ve made this keto marinara sauce, you can keep it in the fridge for several days as long as you use an airtight container. If you anticipate needing to use some keto pasta sauce in the future, you can always make a larger batch and freeze some.
What Goes With Keto Tomato Sauce?
You might be excited about trying a new easy keto tomato sauce recipe. But naturally, you probably want to have some sort of plan for how to use it after you make it. After all, the things that usually go with pasta sauce and spaghetti sauce are generally very high in carbohydrates.
Luckily, there’s no shortage of very low-carb substitutes for just about any high-carbohydrate food. If you’re wondering what the low-carb marinara sauce you’re going to make will go with, here are some general ideas:
- Spaghetti squash (instead of pasta)
- Zucchini noodles
- Cauliflower pizza crust
- Eggplant slices (instead of lasagna pasta)
- Almond flour or coconut flour pizza dough
- Mozzarella sticks (for dipping)
In the next section, we’ll take a look at a couple of recipes in case you want to try your hand at a low-carb main dish.
Recipes: How to Use Keto Tomato Sauce
Now you have an idea of how to use low-carb tomato sauce. Here are some recipes you can try with easy keto tomato sauce:
Spaghetti Squash and Meatballs
Here are the ingredients you’ll need:
- 1 spaghetti squash, about 3 pounds
- 2 tbsp extra virgin olive oil
- 2 tbsp water
- 1/2 cup chopped parsley
- 1/2 cup Parmesan cheese, finely shredded
- 1.25 tsp Italian seasoning
- 1/2 tsp onion powder
- 1/2 tsp salt
- 1/2 tsp black pepper
- 1 pound ground turkey or ground beef
- 4 minced garlic cloves
- 1 28-ounce can crushed tomatoes, no salt added
- 1/4 to 1/2 tsp red pepper flakes
And here’s how to make it:
1. First, prepare the spaghetti squash. Cut it in half, scoop out the seeds, and place each half face-down in a microwave-safe dish. Add some water and microwave roughly 10-15 minutes. You can tell the squash is done when it will easily flake with a fork.
2. Next, get a large skillet. Heat up one tablespoon of the oil on medium heat and then add the flesh of the squash. Cook it until it starts to brown and some of the water evaporates off. This should take about 5-10 minutes. Stir in about 1/4 cup parsley. Cover and set aside.
3. While the squash mixture sits, you can start shaping the meatballs. Get a large bowl and mix together the other 1/4 cup parsley, 1/4 cup Parmesan, 1/2 tsp Italian seasoning, the onion powder, 1/4 tsp of the salt, and the black pepper. Mix in the meat, but be sure you don’t overmix. Divide and shape it into 12 meatballs.
4. Now, take a skillet and heat up the remaining oil. Add the meatballs and cook them on medium-high heat until they are browned evenly; this should take about 4-6 minutes. Clear a space in the pan and cook the chopped garlic about 1 minute.
5. Add in the rest of the salt and Italian seasoning, tomatoes, and red pepper. Simmer the mixture while covered, stirring occasionally. Do this about 10-12 minutes or until meatballs are cooked through.
6. Place the sauce and meatballs over the squash and top with the remainder of the Parmesan.
You might notice that this recipe involves effectively making pasta sauce as well. Of course, if you’ve already made the keto marinara sauce mentioned above, you can add that to the squash and meatballs instead. That can cut down on prep time.
If you’re looking for a slightly different way to use your easy keto tomato sauce, you might want to substitute zucchini noodles. Zucchini noodles taste a little like spaghetti squash, though you will need a special tool to make the noodles from the squash. Of course, if you want some new twists on spaghetti and meatballs that still taste amazing, you can find plenty of free recipes online!
This delicious lasagna recipe only has around 11g carbs per serving. It’s a unique and delicious way to incorporate easy keto tomato sauce into a memorable recipe! Here’s what you’ll need:
- 1 pound ground beef (or turkey if you prefer)
- 1/2 tsp salt
- 1/2 tsp ground black pepper
- 1 tbsp olive oil
- 1/2 cup minced onion
- 1 tsp minced garlic
- 1.5 cups keto pasta sauce
- 1/2 cup drained ricotta cheese
- 1.5 cups shredded mozzarella cheese
- 1 egg
Here’s how to make it:
1. Preheat the oven to 400 degrees Fahrenheit.
2. Put the ground meat in a skillet and stir in salt and pepper. Stir and cook over medium-high heat until it browns and begins to crumble; this should take about 10 minutes. Place the browned meat in a strainer and set it aside for now.
3. Heat up some oil in the same skillet on medium-high heat. Cook the onions until they’re translucent (should take about 4-5 minutes). Then add the garlic and then cook until you can smell it (about 30 seconds).
4. Put the meat back in the skillet. Add and stir the keto pasta sauce and turn off the heat.
5. Now, mix together Parmesan, ricotta, egg, and 1/2 cup mozzarella in a bowl. Take the met and spread it over the bottom of an 8×8 casserole dish. Pour the cheese mixture on top and sprinkle with remaining mozzarella.
6. Bake about 20-25 minutes or until the top of the dish is golden brown.
Breathe New Life Into Your Keto Diet!
If there’s one thing you learn in the keto lifestyle, it’s that there are carbs hiding where you least expect them. And even though store-bought tomato sauce has a lot of added sugar, it’s surprisingly easy to make your own keto tomato sauce at home. And with a little creativity, you can design the perfect sauce for you!
Still have some questions on tomato sauce and how it fits into the keto diet? Here are some helpful answers.
What sauces can you have on keto?
If you’re on a ketogenic diet, you can have a whole range of specialty sauces. Some companies offer special keto pasta sauce, barbeque sauce, etc. If you’re making your own keto sauces, mayonnaise, oil and vinegar, mustard, ranch dressing, and bleu cheese dressing are a few keto-friendly ingredients you might want to use. Low-carb tomato sauce is also a good choice as long as you don’t eat an excessive amount.
Is tomato sauce full of carbs?
Tomato sauces with no added sugar typically aren’t too high in carbs. In many cases, they have 6 net carbs or fewer per serving. Tomatoes themselves do have some carbs, so tomato sauces with a lot of added sugar may have an excessive number of carbs for someone on a keto diet.
Can tomato sauce kick you out of ketosis?
Yes, it can. Eating too many sugars in general (even if they are natural sugars) can kick you out of ketosis, so it’s important to keep track of your macros on a keto diet. Even if it’s keto tomato sauce, eating far too much at once can kick you out of ketosis.
Can I eat marinara sauce on keto?
Yes, you can, as long as you don’t eat enough to take you out of ketosis. If you’re getting store-bought sauce, be sure to check labels to make sure you aren’t consuming too much added sugar. Alternatively, you can make your own keto tomato sauce as well.