The Ultimate Guide to the Keto Diet: Foods to Eat and How to Get Enough Fiber

The ketogenic (keto) diet is a high-fat, very low-carbohydrate, and moderate-protein diet. There are lots of healthy foods you can eat on the keto diet, but it’s important to make sure you get enough fiber.

Foods you can eat on the keto diet include fish and seafood, meat and poultry, non-starchy vegetables like bell peppers, broccoli, and zucchini, avocados, berries, nuts and seeds, eggs, high-fat dairy products, olive oil and other oils, and high-cocoa chocolate.

Research suggests that following the keto diet can help you burn fat while making you feel less hungry. However, some of the weight loss you see at the beginning can actually be due to the release of stored water.

Very restrictive diets that lead to fast weight loss can be bad for your health and actually make it harder to maintain your weight goals long-term. Research has shown that losing weight quickly can slow down the rate at which your body burns the energy it gets from food.

Before making the decision to switch to a keto diet, you should consider whether you actually need to lose weight.

Obesity increases the risk of health conditions like heart disease, type 2 diabetes, and certain cancers. But if your body mass index (BMI) is in the underweight range or near the bottom of the moderate range, you don’t need to lose weight.

Read on to learn more about the foods you can eat on a keto diet and how to make sure you’re getting enough fiber.

What is the keto diet?

The keto diet was originally developed by experts to treat certain types of childhood epilepsy. Doctors may recommend it when other treatments don’t work, and people following a keto diet for epilepsy should do so under careful supervision by a healthcare professional.

More recently, keto has become popular among people trying to lose weight.

People following a standard keto diet generally aim to get 70–80% of their total daily calories from fat, 10–20% from protein, and 5–10% from carbohydrates. For a 2,000-calorie diet, that’s around 25–50 grams of carbohydrate, 150–180 g of fat, and 50–100 g of protein each day.

The keto diet works by getting your body to change the fuel it uses for energy. Normally, carbohydrates from your food are broken down into glucose, which is the body’s main source of energy.

But when you eat fewer carbs, your body starts to use fat as energy instead by turning it into substances called ketones.

This is called ketogenesis, and it usually begins about 3 to 4 days after you start restricting your carb intake.

Foods you can eat on the keto diet

One of the risks of going on the keto diet is that you might not eat enough fiber and B vitamins.

That’s because many foods high in fiber and B vitamins — such as whole grains, fruits, vegetables, and legumes like lentils and chickpeas — also contain a significant amount of carbs.

Getting enough fiber in your diet is very important for the health of your gut microbiome, which is the community of trillions of microbes that live in your gut. These microbes digest fiber and turn it into chemicals that are linked to health benefits.

As we’ll see below, low-carb plants that still contain a good amount of fiber include non-starchy vegetables like broccoli, cauliflower, and zucchini, as well as avocados, nuts, seeds, and berries.

The fiber in the plants you eat doesn’t count toward your carbohydrate intake because you don’t fully digest it. When people talk about the “net carbs” in a food, they mean the total carbohydrates minus the part that’s fiber.

The following is a list of the best healthy food options for a keto diet.

1. Fish and seafood

Fish and shellfish are good choices if you’re following a keto diet. Salmon is high in essential nutrients like omega-3 and B vitamins but very low in carbs. Shrimp and lobster also work well for keto.

Macronutrients per 3 ounces (85 g) in fish and seafood:

• Salmon: 0 g carbs, 4 g fat, 17 g protein

• Flounder: 0 g carbs, 2 g fat, 11 g protein

• Crab: 0 g carbs, 1 g fat, 15 g protein

• Lobster: 0 g, 1 g fat, 14 g protein

2. Meat and poultry

Meat and poultry are popular with people on the keto diet because they’re high in fat and very low in carbs.

However, scientists have found links between eating too much meat on a regular basis and health conditions like heart disease, type 2 diabetes, and excess weight. That’s why it’s best to eat meat and poultry in moderation.

Macronutrients per 3.5 ounces (100 g) in meat and poultry:

• Turkey: 0 g carbs, 12 g fat, 27 g protein

• Beef: 0 g carbs, 6 g fat, 123 g protein

• Chicken: 0 g carbs, 3 g fat, 32 g protein

• Sausages: 2 g carbs, 26 g fat, 18 g protein

3. Non-starchy vegetables

Vegetables that are low in carbs but still contain fiber are a good option for the keto diet.

They also contain plenty of micronutrients and antioxidants, which are essential for your health.

Non-starchy vegetables can make a great substitute for high-carbohydrate foods. For example, you can use cauliflower to make “rice” and zucchini to make noodles.

Macronutrients per 3.5 ounces (100 g) in low-carb, high-fiber vegetables:

• Zucchini: 3 g carbs, 1 g fiber, 0 g fat, 3 g protein

• Cauliflower: 4 g carbs, 2 g fiber, 0 g fat, 2 g protein

• Bell Peppers: 5 g carbs, 2 g fiber, 0 g fat, 1 g protein

• Broccoli: 6 g carbs, 2 g fiber, 0 g fat, 3 g protein

4. Avocados

Avocados are a really popular choice with people following the keto diet since a whole avocado contains only 17 g of carbs — of which 14 g is fiber — and 30 g of fat. They are also high in many vitamins and minerals, including potassium and B vitamins.

Research shows that eating avocados regularly can reduce levels of “bad” cholesterol and improve your heart health.

5. Berries

A lot of fruits are difficult to include in a keto diet because of their high carbohydrate content. But berries are relatively low in carbs and contain healthy antioxidants.

Macronutrients per 3.5 ounces (100 g) in berries:

• Strawberries: 8 g carbs, 2 g fiber, 0 g fat, 1 g protein

• Blackberries: 10 g carbs, 5 g fiber, 0 g fat, 1 g protein

• Raspberries: 12 g carbs, 7 g fiber, 0 g fat, 1 g protein

• Blueberries: 15 g carbs, 2 g fiber, 0 g fat, 1 g protein

6. Nuts and seeds

Nuts and seeds are a healthy, high-fat, low-carb food. They also contain plenty of fiber.

Eating nuts has been linked to a lower risk of health conditions including heart disease and diabetes.

Although nuts and seeds are generally low in carbohydrates, there is some variation between different types.

Macronutrients per 1 ounce (28 g) in nuts and seeds:

• Pumpkin seeds: 3 g carbs, 2 g fiber, 14 g fat, 9 g protein

• Almonds: 6 g carbs, 4 g fiber, 14 g fat, 6 g protein

• Cashews: 9 g carbs, 1 g fiber, 12 g fat, 5 g protein

• Chia seeds: 12 g carbs, 11 g fiber, 9 g fat, 5 g protein

7. Eggs

Eggs are an easy and affordable source of fat and protein while also being low in carbohydrates, making them a good choice for those following a keto diet.

While previous recommendations warned against eating more than 2 eggs a week, the latest research found that it’s fine for most people to eat 1 egg every day, or 7 eggs in a week.

8. High-fat dairy products

High-fat dairy products are a good source of protein as well as fat.

Some scientists have linked certain dairy products with health benefits. For instance, yogurt can keep you fuller for longer and provides beneficial probiotics for your gut.

But not everyone agrees. A recent study found that people who substituted carbs with animal products were more likely to die during the 25-year follow-up than those who substituted plant-based options like nuts.

It might be a good idea to balance your dairy intake with plant foods while you are on the keto diet.

9. Oil

Some oils are a healthy source of fat and contain no carbohydrates. These include olive, avocado, canola, nut, and seed oils, like flax and hemp oil.

Research has shown that olive oil can protect against heart disease and certain cancers. Both olives and olive oil are a good choice for the keto diet, as they have the same health benefits and have almost no carbs.

Some oils, like avocado, sunflower, and rice bran oil, are more stable when cooking at a high heat.

10. High-cocoa chocolate

Chocolate with a high cocoa content is a good source of antioxidants, including flavanols. Research suggests that it can improve heart health.

Keto-friendly chocolate should contain 70% cocoa or more. Lower cocoa percentage chocolate has a higher sugar content, which will increase your carbohydrate intake.

A 3.5 ounce portion (100 g) of 70% cocoa chocolate contains 43 g of carbohydrates, 7 g of fiber, 47 g of fat, and 7 g of protein.

11. Coffee and tea without sugar

Tea and coffee are good options for a carb-free drink. Both are linked to a large range of health benefits, including living a longer and healthier life.

These benefits are found for both caffeinated and decaffeinated versions, so if you’re sensitive to caffeine or it’s late in the day, choose a decaf option.

Takeaway

It’s possible to follow a keto diet while still eating healthily, as long as you make sure you get enough fiber by eating plenty of plant foods and stick to moderate amounts of meat and dairy.

Lower carb foods that contain a good amount of fiber include non-starchy vegetables like broccoli, cauliflower, and zucchini, as well as nuts and seeds, avocados, and berries.

Although the keto diet can lead to weight loss, the data also shows there is no one-size-fits-all approach to food and weight. The keto diet works well for some people, but not so well for others.

We also know that some people’s bodies don’t cope well with high amounts of fat in their diet. Eating a lot of fat can put them at risk of dietary inflammation.

Your overall health and weight will benefit if you eat the best foods for your body.