When it comes to low-carb diets, we know that it is challenging, if not impossible, to avoid carbs altogether. At best, we can strive to limit our carb intake to a minimum. However, that being said, are there ‘”good” and “bad” carbs when it comes to your diet? And do we want to avoid all carbs entirely altogether?
When it comes to the Keto diet, we try to limit our daily carb intake to stay in ketosis. Therefore the most obvious strategy is to remove as many carbs from our diet as possible. However, is it possible to eat healthy low-carb foods and still stay in ketosis? In this article, we discuss how carbs impact our diet and the worst and best carb (carbohydrate) on Keto.
First Off, What Are Carbs?
Along with fat and protein, carbohydrates are a macronutrient. These three nutrients make up the bulk of our dietary needs and supply the required calories or energy. These macronutrients are found in almost all of our foods, no matter if it is a meal or raw ingredients. The differences lie in the quantities in which each macronutrient is present. For example, an avocado is generally found to be 75% fat, 20% carbs, and 5% protein.
On the other hand, a banana is around 95% carbs, with the remaining 5% made up of fat and protein. Clearly, bananas are not a good choice for a keto diet. On the other hand, one might question the avocado. After all, it is chock full of good fat. However, the 20% carb content should give you pause. Thankfully, the seemingly high carb content is not a problem, due to the nature of these carbs, meaning that this delicious and nutritious food can remain a part of your meal plan. To see why let’s take a closer look at what carbs are.
While the term carb or carbohydrate is most frequently used, it is, in fact, a catch-all term used that includes three nutrients: starch, fiber, and sugar. These nutrients are present in various foods in differing quantities, directly impacting whether a food is keto-friendly or not.
Carbohydrates can be further broken down into two categories that include simple and complex carbohydrates. Of the three nutrients that makeup carbohydrates, sugar is a simple carb, while starch and fiber are complex carbs.
The distinction between simple and complex carbs lies in the number of sugar molecules they are comprised of. Simple carbs are defined as short-chain carbohydrates, while complex carbs are defined as long-chain carbs.
However, you may have come across other terms used to describe sugars in your quest to adopt a healthy lifestyle. Terms such as monosaccharide and disaccharide are used frequently when talking about sugars by manufacturers and those working in the field of nutrition. To understand that relationship of sugar to food, it helps to define and understand these terms.
Monosaccharide: the most simple unit of carbohydrates, they are single sugars (mono means one, and saccharide means sugar). This includes:
- Glucose: the most abundant and most basic fuel for energy production in the body.
- Fructose: simple sugars found in plants, especially fruit.
- Galactose: found in foods such as milk.
Disaccharide: carbs that are composed of two sugar molecules. For example, two glucose molecules. These sugars include:
- Lactose: composed of glucose and galactose. Found in milk.
- Maltose: composed of two glucose molecules. Found in germinating plants.
- Sucrose: composed of fructose and glucose. Found in plants, such as sugar cane.
Oligosaccharide: complex sugars composed of (typically) three to ten simple sugars. Found in plant fibers, they are a source of dietary fiber improving gastrointestinal health. These sugars are sold as nutritional supplements.
Polysaccharide: complex sugars composed of long chains (usually more than ten)of monosaccharides. These complex sugars form the majority of large molecules such as starch and cellulose.
What Are Simple Carbs?
Simple carbs are classified as carbohydrates that are composed of simple sugars, such as mono- and di-saccharides. These carbs can be found naturally in foods such as fruit (fructose), honey (glucose and fructose), and milk (galactose).
However, in our modern diets, they are more commonly found in the highly processed foods we consume daily. Such foods include table sugar, corn sugar, and other derived plant sugars, as well as highly processed foods such as white rice and white flour.
The processes that these foods go through form their raw form to when they reach our table remove most of the nutrients and beneficial properties, leaving behind mostly carbs in the form of simple sugars, and thus empty calories.
Simple carbs are easy to digest and provide a burst of energy that quickly recedes to leave you feeling drained and exhausted. Think sugar-rush, followed by the crash.
However, simple carbs have their place in our diets when consumed in the right portions and times. “Good” simple carbs with natural origins such as those found in fruit and milk provide an initial energy boost. This initial boost is then sustained by energy fueled by burning complex carbs.
On the other hand, “Bad” carbs are best excluded from your diet as they only provide empty calories and lack nutritional value.
Simple Carbs Are:
- Short-chain sugars (one or two sugars)
- Unrefined (good): Honey, Milk, Fruit, etc.
- Refined (bad): Table Sugar, White flour, White Rice, etc
What Are Complex Carbs?
Complex carbs, as opposed to simple short-chain carbs, are composed of long chains of sugars (three or more). These carbs are found in whole grains such as oats, wild rice, whole wheat flour, and unrefined cereals.
Unlike the simple carbs, complex carbs in their intact form are a varied composition of fiber, starch, and sugars. These nutrients are essential to the bodies well being and help regulate the body’s ability to process these foods as well as many other functions.
Complex carbs are harder for the body to breakdown and therefore release their sugars slowly into the bloodstream, resulting in a steady influx of energy.
This constant stream allows your body to regulate the increased sugar efficiently. This regulation is further enhanced by the presence of fiber in complex carbs. Fiber is often a significant component of complex carbs and is generally undigested and therefore adds no additional sugars to the food.
For this reason, foods with high fiber content have fewer net carbs than simple carbs.
Complex Carbs are:
- Long-chain Sugars (more than two)
- Found in a variety of foods
- Starchy Vegetables
- Legumes
- Whole Grains and Cereals
The Ketogenic Approach to Carbs
In what is generally considered to be a traditional healthy diet, the question of what types of carbs to eat would be easy to answer. For this conventional type of diet, eliminating processed foods and added sugars is all it takes. However, on the Keto diet, it’s not as simple as this. Before you start to analyze the types of carbs you include in your diet, it is essential to make sure that you are adhering to the basic rules of the Ketogenic diet.
1. Eat the Recommended Amount of Carbs Per Day: while this varies from person to person—you can find your personal carb limit if you want—and it may change over time; the accepted carb limit is 50g or less per day. Many sources recommend eating as little as 20g of carbs per day.
2. Stay Away From High-Carb Foods: any food with a high carb content should be avoided as consuming too many carbs risks being kicked out of ketosis. Foods that are high in carbs include:
- Foods with added sugar
- Processed and refined foods
- Grains
- Legumes
- Starchy vegetables
- Natural foods high in sugar, such as honey and maple syrup
- Most processed drinks including fruit juices
3. Eat Low-Carb Foods: when it comes to sources of carbs, eat low carb options that will allow you to have a balanced diet and get all of the necessary micronutrients your body requires.
Foods that are low in carbs include:
- Leafy greens
- Veggies that grow above ground (non-starchy vegetables)
- Berries
4. Keep Fruit Consumption in Moderation: although fruit is generally considered to be healthy food options, they are jam-packed with simple carbs. Consuming too much will spike your blood sugar and bump you out of ketosis. Instead, try eating berries, which are lower in sugar. However, you still need to watch how much you eat.
What To Consider When Choosing Your Food
When determining the right food for the keto diet in terms of carb content, it is vital to consider carbs as a whole and as the individual components. As previously mentioned, when we talk about carbs, we are usually talking about three nutrients; starch, sugar, and fiber.
These three nutrients comprise the total carb content of the food and are present in different quantities in different foods. In some foods, one of these nutrients may be present in much higher amounts than the others.
For example, sweet potatoes are high in starch—about 53%—and in simple sugars—about 32%—, with the remaining 15% made up of dietary fiber. On the other hand, berries are low in starches but contain proportionally more simple sugars and fiber.
On the keto diet, it is essential to consider each of these components of carbs individually to determine if the food is appropriate for you or not.
First Things First: Sugar
When we look at our food to find the sugar content, we are looking at the simple sugars. These sugars, as discussed earlier, are quickly broken down by the body and absorbed into the bloodstream. These simple sugars have their place when consumed in moderation and when they are derived from a natural source.
However, even in moderation, to successfully stay in ketosis, it is better to avoid any food that is proportionally high in simple sugars. With this in mind, the more critical components to keep in mind are starch and fiber.
Let’s Look At Starch
Starches are long-chain carbohydrates (complex carbs) that are composed of many individual sugar units. When ingested, these long chains are broken through digestion into smaller sugars, which are then used to fuel the body.
Starches are further broken down into three categories based on how they are disgested.
- Rapidly Digested Starch: this type of starch is easily broken down and may spike the blood sugar.
- Slowly Digested Starch: this type of starch is difficult to break down, resulting in a slow release of sugar into the bloodstream over a longer time.
- Resistant Starch: this type of starch is not broken down by the body and functions like fiber. It is beneficial for maintaining a healthy population of beneficial gut bacteria.
Starches are found in many of the foods we encounter in our day to day life. Some of these foods include rice, corn, potatoes, peas, beans, whole grain, oats, legumes, and many others. Even some foods you would not consider are full of starch, such as green bananas, which are converted to sugars as they ripen.
Although starches have a place in traditional eating and healthy diets, they should be avoided when following the keto diet. The eventual breakdown of the starches into sugars is enough to stop ketogenesis.
What About Fiber?
Like starch, fiber is composed of long chains of individual sugar molecules. However, unlike starch, these chains are relatively unbreakable by your digestive system. This results in the majority of the fiber passing through your system without having a net impact on your caloric intake.
Fiber is found in many plant-based foods and make up a large percentage of the total carb content of many. This undigestable fiber has various health benefits, including aiding in digestion—keeping you “regular”—and helping maintain a healthy gut biome. Evidence suggests that it may also aid in weight loss, decrease the chances of heart disease, diabetes, and colon cancer.
Fiber is found in two varieties:
- Soluble: also called prebiotic fiber, this type of fiber aids in slowing digestion by absorbing water while lowering blood glucose and cholesterol. It further aids in helping one feel full, resulting in reduced consumption of food. Sources of soluble fiber include oat bran, barley, nuts, seeds, beans, lentils, peas, and some fruits and vegetables. Psyllium, a common fiber supplement, is an excellent additional source of soluble fiber.
- Insoluble: this type of fiber aids in the swift movement of food through the digestive tract while adding bulk to your stool. Its consumption has been linked with the reduction in the risk of diabetes and the improvement of gut health. Sources of insoluble fiber include wheat bran, seeds, vegetables, and whole grains.
Net Carbs vs. Total Carbs
When you look at the nutritional information describing a food, you will notice both a label indicating the net carbs as well as the total carbs of the item. And most of the time, these will not be the same number. This is because the total carb content of food includes fiber. Since the majority of the fiber is indigestible, these carbs are not relevant when considering the carb limit for the keto diet. Instead, net carbs give a more accurate accounting of the number of relevant carbs in your diet.
To calculate the net carbs in a particular food, use this formula:
Total Carbohydrates – Total Fiber = Net Carbohydrates
So What Kinds Of Carbs Should I Eat?
While defining good and bad carbs in a traditional healthy diet is relatively easy, this does not work when it comes to the keto diet. The only real way of knowing what foods (containing carbs) to eat is to take a close look at the nutritional content and determine it for yourself. However, as a general rule of thumb, it is usually better to eat foods that are high in fiber and low in sugars and starches. To make this easier, let’s take a look at some common foods that are sources of “good” carbs on the keto diet.
Vegetables
Vegetables are a key part of the keto diet. Not only do they provide all-important fiber, but they are also a primary source of many essential vitamins and minerals. The vegetables most suited to the keto diet are those low in carbs but high in nutrients. While all the veggies included in the DO EAT! list are keto-friendly, understanding their nutritional impact and maintaining portion control is still essential.
DO EAT!
Leafy Greens: Above ground veggies that are dark in color are a good indicator of high fiber content while being low in digestible carbs. Furthermore, they are rich in antioxidants, vitamins, and minerals.
Some of these veggies include:
- Collards
- Watercress
- Spinach
- Mustard Greens
- Chard
Cruciferous Vegetables: Above ground veggies that tend to be “meaty” but are low-calorie and rich in folate, vitamins C, E, and K, and fiber. In addition, they are rich sources of phytonutrients, which research has indicated have cancer-fighting properties as well as reducing inflammation, giving them a surge in popularity. These veggies are an excellent addition to any meal given their unique and robust flavors.
Cruciferous veggies include:
- Arugula
- Bok Choy
- Broccoli
- Brussels sprouts
- Cabbage
- Cauliflower
- Kale
- Radish
- Turnips
Other Veggies: apart from leafy greens and cruciferous veggies, there are a whole host of other delicious and nutritious vegetables that you can include in your diet.
Some of these include:
- Celery
- Cucumber
- Zucchini
- Mushrooms (not technically veggies but delicious!)
- Bellpepper
- Green Beans
- Lettuce
Vegetables
Type Total Carbs (g) Net Carbs (g) Fiber (g)
Leafy Greens
Collards 5 1 4
Watercress 1.3 0.8 0.5
Spinach 3.6 1.4 2.2
Mustard Greens 4.7 1.5 3.2
Cruciferous Veggies
Arugula 3.7 2.1 1.6
Bok Choy 2.2 1.2 1
Broccoli 7 4.4 2.6
Brussel Sprouts 9 5.2 3.8
Cabbage 6 3.5 2.5
Cauliflower 5 3 2
Kale 8.8 5.2 3.6
Radish 4.1 2.5 1.6
Turnips 6 4.2 1.8
Other
Celery 3 1.5 1.5
Cucumber 3.6 3.1 0.5
Zucchini 3.1 2.1 1
Mushrooms 3.3 2.3 1
Bell peppers 4.6 2.9 1.7
Green Beans 7 3.6 3.4
Lettuce 2.9 1.6 1.3
EAT IN MODERATION!
Some veggies are useful for adding flavor to our meals, and others are too high in carbs to be eaten with regularity. Eat these in moderation and pay attention to their nutritional information.
These include:
- Some Below Ground Veggies
- Onions
- Garlic
- Squash
- Nightshade
- Tomatoes
- Eggplant
- Peppers
Vegetables
| Type | Total Carbs (g) | Net Carbs (g) | Fiber (g) |
|---|---|---|---|
| Below Ground Veg | |||
| White Onion | 9 | 7.3 | 1.7 |
| Red Onion | 10.1 | 8.7 | 1.4 |
| Garlic | 33 | 30.9 | 2.1 |
| Squash | |||
| Gem Squash | 3.6 | 3.3 | 0.3 |
| Spaghetti Squash | 7 | 5.5 | 1.5 |
| Hubbard Squash | 8.6 | 6.9 | 1.7 |
| Acorn Squash | 10 | 8.5 | 1.5 |
| Butternut Squash | 12 | 10 | 2 |
| Nightshade | |||
| Tomatoes | 3.9 | 2.7 | 1.2 |
| Eggplant | 6.5 | 3.5 | 3 |
| Yellow Peppers | 6.3 | 5.4 | 0.9 |
| Red Pepper | 9 | 7.5 | 1.5 |
DO NOT EAT!
Some veggies are too high in carbs to be included in the keto diet. These include those that are high in starch as well as high in sugar.
Some of these veggies include:
- Potatoes
- Sweet Potatoes
- Corn
- Most Beans
- Most Squash
- Pulses
Vegetables
| Type | Total Carbs (g) | Net Carbs (g) | Fiber (g) |
|---|---|---|---|
| Potatoes | |||
| Sweet Potato | 20 | 17 | 3 |
| Regular Potato | 17 | 4.8 | 2.2 |
| Corn | |||
| Sweet Yellow Corn | 19 | 16.3 | 2.7 |
| Beans | |||
| Black Beans | 16.6 | 9.7 | 6.9 |
| Broad/Fava Beans | 18 | 10 | 8 |
| Lima Beans | 21 | 14 | 7 |
| Soy Beans | 30 | 21 | 9 |
| Kidney Beans | 60 | 35 | 25 |
| Navy Beans | 61 | 37 | 24 |
| Mung Beans | 63 | 47 | 16 |
| Pinto Beans | 63 | 47 | 16 |
| Squash | |||
| Peanut Squash | 15.9 | 13.3 | 2.6 |
| Banana Squash | 21.5 | 14.9 | 6.6 |
| Pulses | |||
| Lentils | 20 | 12 | 8 |
| Chickpeas | 24 | 21 | 3 |
Fruit/Berries
When it comes to fruit, most are too high in sugar to be a part of the keto diet. Instead, it is recommended that berries are included as an alternative as they are high in fiber and more moderate in sugar content compared to fruit.
DO EAT!
Berries: high in antioxidants and fiber and moderate in sugar content, barries are an excellent treat to be eaten with your breakfast or as a snack. Just be sure to eat them in moderation as they will kick you out of ketosis if you overindulge.
Some keto-friendly berries include:
- Blackberries
- Strawberries
- Raspberries
Avocado: yes! Technically an avocado is a berry. And it’s great for the keto diet! High in good fats as well as chock full of fiber, these delicious berries are an excellent choice for an easy breakfast or tasty snack. They are also a great source of potassium, a vital nutrient for your body’s functions.
Citrus: although many citrus fruits are high in sugar, they can be used as garnishes and to add flavor to dishes if they are used in moderation. Plus, they are an excellent source of vitamin C, as well as flavonoids.
Fruit/Berries
| Type | Total Carbs (g) | Net Carbs (g) | Fiber (g) |
|---|---|---|---|
| Berries | |||
| Blackberries | 10 | 5 | 5 |
| Strawberries | 8 | 6 | 2 |
| Raspberries | 12 | 5 | 7 |
| Avocado | 9 | 2 | 7 |
| Citrus | |||
| Lemon | 9 | 6.2 | 2.8 |
| Lime | 11 | 8.2 | 2.8 |
| Grapefruit | 11 | 9.4 | 1.6 |
DO NOT EAT!
Most other fruits are high in sugar and should be avoided. This includes juices, smoothies, and watered-down drinks like lemonade. Then some just are the bane of ketosis, packed with sugars and starches.
Some fruit to avoid are:
- Dates
- Bananas
- Pineapples
- Grapes
- Plantains
- Apples
Fruit/Berries
| Type | Total Carbs (g) | Net Carbs (g) | Fiber (g) |
|---|---|---|---|
| Dates | 75 | 68 | 7 |
| Bananas | 23 | 21.4 | 2.6 |
| Pineapples | 13 | 1.4 | 11.6 |
| Grapes | 17 | 16.1 | 0.9 |
| Plantains | 32 | 29.7 | 2.3 |
| Apples | 14 | 11.6 | 2.4 |
Nuts and Seeds
Nuts and seeds are an excellent source of good fats and protein. However, many nuts also contain significant amounts of carbs. As with all foods, it is vital to maintain portion control as the benefits can be quickly overcome when consuming too much. Nuts and seeds are a great way to add flavor and texture to meals when raw or cooked.
DO EAT!
Fatty, low carb nuts/seeds: these nuts are an excellent source of good fats and can be consumed with meals and in higher portions.
These nuts include:
- Macadamia Nuts
- Brazil Nuts
- Pecans
- Flax Seeds
- Hemp Seeds
- Sesame Seeds
- Pumpkin Seeds
Fatty, moderate carb nuts/seeds: these nuts are appropriate to be used as a condiment to supplement taste and texture. But with these, there is too much of a good thing.
These nuts include:
- Walnuts
- Almonds
- Hazelnuts
- Peanuts
- Pine Nuts
- Sunflower Seeds
- Sesame Seeds
Nut Butters/Flours: These spreads and flours vary in their carb contents and should be approached with caution. Make sure you are confident of the serving size and how it will affect your diet. Otherwise, these are a great way to add some zest and variety to your meals. Many delicious keto desserts can be made from these ingredients.
Some nut butter/flours include:
- Flaxseed Flour
- Chia seed Flour
- Almond Flour/Butter
- Coconut Flour/Butter
Nuts/Seeds
| Type | Total Carbs (g) | Net Carbs (g) | Fiber (g) |
|---|---|---|---|
| Fatty, Low Carb Nuts/Seeds | |||
| Macadamia Nuts | 14 | 5 | 9 |
| Brazil Nuts | 12 | 4 | 8 |
| Pecan | 14 | 4.4 | 9.6 |
| Flax Seeds | 29 | 2 | 27 |
| Hemp seeds | 8.7 | 4.7 | 4 |
| Sesame Seeds | 23.5 | 11.5 | 12 |
| Pumpkin Seeds | 11 | 5 | 6 |
| Fatty, Moderate Carb Nuts/Seeds | |||
| Walnuts | 14 | 7.3 | 6.7 |
| Almonds | 22 | 9 | 13 |
| Hazelnuts | 17 | 7.3 | 9.7 |
| Peanuts | 21 | 12.6 | 8.4 |
| Pinenuts | 13 | 9.3 | 3.7 |
| Sunflower Seeds | 20 | 11.4 | 8.6 |
| Nut Butters/Flours | |||
| Flaxseed Flour | 30 | 2 | 28 |
| Chia seed Flour | 42.1 | 7.7 | 34.4 |
| Almond Flour/Butter | 20 | 8 | 12 |
| Coconut Flour/Butter | 64 | 22 | 42 |
DO NOT EAT!
Some nuts and seeds are very high in carbs, and even a handful is enough to knock you out of ketosis. These are best avoided entirely and replaced with something more keto-friendly.
These include:
- Pistachios
- Cashews
Nuts/Seeds
| Type | Total Carbs (g) | Net Carbs (g) | Fiber (g) |
|---|---|---|---|
| Fatty, High Carb Nuts/Seeds | |||
| Pistachios | 28 | 18 | 10 |
| Cashews | 33 | 30 | 3 |
Other Sources of Carbs
While there are other sources of carbs in the foods that we eat, the majority come from plant-based sources such as the foods listed above. Sources such as dairy and spices that we use are a small percentage of the carbs that we ingest daily. That doesn’t mean that we can completely ignore them, but must approach them in the same way.
The Takeaway
Carbs make up a large percentage of the foods that we eat daily and are a staple crop in the world. Indeed without carbs, feeding the population fo the world would be an overwhelming task. For those who follow the keto diet, this presents an opportunity to discover the differences in carbs and the benefits and drawbacks they present. One learns that it is challenging to label carbs good or bad, but rather good or bad for you.
However, in general, and especially on a low carb diet, the prevailing rule to follow is complex carbs trump simple carbs, and unrefined carbs trump refined carbs. On the keto diet, the majority of the carbs consumed should come from unrefined complex carbs from nutritious sources. By following the simple guides listed outlined in this article, you should find it easy to determine the worst and best carb (carbohydrate) on keto.