The ketogenic diet has become popular.
Studies have found that this very low carb, high fat diet is effective for weight loss, diabetes, and epilepsy (1, 2, 3).
There’s also early evidence to show that it may be beneficial for certain cancers, Alzheimer’s disease, and other diseases, too.
Still, higher quality research on the diet is still needed to determine its long-term safety and efficacy (1, 4, 5).
A ketogenic diet typically limits carbs to 20 to 50 grams per day. While this may seem challenging, many nutritious foods can easily fit into this way of eating.
Here are some healthy foods to eat on a ketogenic diet.
Fish and shellfish are very keto-friendly foods. Salmon and other fish are rich in B vitamins, potassium, and selenium, yet virtually carb-free (6).
However, the carbs in different types of shellfish vary. For instance, while shrimp and most crabs contain no carbs, other types of shellfish do (7, 8).
While these shellfish can still be included on a ketogenic diet, it’s important to account for these carbs when you’re trying to stay within a narrow range.
Here are the carb counts for 3.5-ounce (100-gram) servings of some popular types of shellfish (9, 10, 11, 12, 13):
clams: 4 grams / mussels: 4 grams / octopus: 4 grams / oysters: 3 grams / squid: 3 grams
Salmon, sardines, mackerel, and other fatty fish are very high in omega-3 fats, which have been found to lower insulin levels and increase insulin sensitivity in people who have overweight and obesity (14).
In addition, frequent fish intake has been linked to a decreased risk of disease and improved cognitive health (14, 15).
The American Heart Association recommends consuming 1 to 2 seafood meals every week (16).
SUMMARY: Many types of seafood are carb-free or very low in carbs. Fish and shellfish are also good sources of vitamins, minerals, and omega-3s.
Non-starchy vegetables are low in calories and carbs, but high in many nutrients, including vitamin C and several minerals. Vegetables and other plants contain fiber, which your body doesn’t digest and absorb like other carbs.
Therefore, look at their digestible (or net) carb count, which is total carbs minus fiber. The term “net carbs” simply refers to carbs that are absorbed by the body.
Note that net carbs and their effects on the body are somewhat controversial, and more research is needed.
Many vegetables contain very few net carbs. However, consuming one serving of “starchy” vegetables like potatoes, yams, or beets could put you over your entire carb limit for the day.
The net carb count for non-starchy vegetables ranges from less than 1 gram for 1 cup of raw spinach to 7 grams for 1 cup of cooked Brussels sprouts (17, 18).
Vegetables also contain antioxidants that help protect against free radicals, which are unstable molecules that can cause cell damage (19, 20).
What’s more, cruciferous vegetables like kale, broccoli, and cauliflower have been linked to decreased cancer and heart disease risk (21, 22).
Low carb veggies make great substitutes for higher carb foods.
For instance: cauliflower can be used to mimic rice or mashed potatoes
“zoodles” can be created from zucchini spaghetti squash is a natural substitute for spaghetti
Here are some examples of keto-friendly vegetables to include in your eating plan.
Keto vegetable list:
asparagus / avocado / broccoli / cabbage / cauliflower / cucumber / green beans / eggplant /kale / lettuce / olives / peppers (especially green) /spinach / tomatoes / zucchini
SUMMARY: The net carbs in non-starchy vegetables range from 1 to 8 grams per cup. Vegetables are nutritious, versatile, and may help reduce the risk of disease.
There are hundreds of types of cheese. Fortunately, most are very low in carbs and high in fat, which makes them a great fit for a ketogenic diet.
One ounce (28 grams) of cheddar cheese provides 1 gram of carbs, 6.5 grams of protein, and a good amount of calcium (23).
Cheese is high in saturated fat, but it hasn’t been shown to increase the risk of heart disease. In fact, some studies suggest that cheese may help protect against heart disease (24, 25).
Cheese also contains conjugated linoleic acid, which is a fat that has been linked to fat loss and improvements in body composition (26).
In addition, eating cheese regularly may help reduce the loss of muscle mass and strength that occurs with aging.
A 12-week study in older adults found that those who consumed 7 ounces (210 grams) of ricotta cheese per day experienced less muscle mass and muscle strength loss over the course of the study than others (27).
Here are some cheeses that are lower in carbs for a keto diet.
Keto cheese list:
blue cheese / brie / camembert / cheddar / chevre / colby jack / cottage cheese / cream cheesefeta / goat cheese / halloumi / Havarti / Limburger / manchego / mascarpone / mozzarella /muenster / parmesan / pepper jack / provalone / romano / string cheese / Swiss
SUMMARY: Cheese is rich in protein, calcium, and beneficial fatty acids, yet contains a minimal amount of carbs.
Avocados are incredibly healthy; 3.5 ounces (100 grams), or about one-half of a medium avocado, contain 9 grams of carbs.
However, 7 of these are fiber, so its net carb count is only 2 grams (28).
Avocados are high in several vitamins and minerals, including potassium, an important mineral many people may not get enough of. What’s more, a higher potassium intake may help make the transition to a ketogenic diet easier (29).
In addition, avocados may help improve cholesterol and triglyceride levels.
One study found that participants eating one avocado per day had beneficial effects for their cardio‐metabolic risk factors including lower levels of LDL (bad) cholesterol. (30).
SUMMARY: Avocados contain 2 grams of net carbs per serving and are high in fiber and several nutrients, including potassium. In addition, they may help improve heart health markers.
Meat and poultry
Meat and poultry are considered staple foods on a ketogenic diet.
Fresh meat and poultry contain no carbs and are rich in B vitamins and several important minerals (31, 32).
They’re also a great source of high-quality protein, which has been shown to help preserve muscle mass during a very low carb diet (33, 34).
One study in older women found that consuming a diet high in fatty meat led to HDL (good) cholesterol levels that were 5% higher than on a low fat, high carb diet (24).
It’s best to choose grass-fed meat, if possible. That’s because animals that eat grass produce meat with higher amounts of omega-3 fats, conjugated linoleic acid, and antioxidants than meat from grain-fed animals (35).
SUMMARY: Meat and poultry do not contain carbs and are rich in high-quality protein and several nutrients. Grass-fed meat is the healthiest choice.
Eggs are one of the healthiest and most versatile foods on the planet.
One large egg contains less than 1 gram of carbs and about 6 grams of protein, making eggs an ideal food for a ketogenic lifestyle (36).
In addition, eggs have been shown to trigger hormones that increase feelings of fullness and satiety (37, 38).
It’s important to eat the entire egg, as most of an egg’s nutrients are found in the yolk. This includes the antioxidants lutein and zeaxanthin, which help protect eye health (39).
Although egg yolks are high in cholesterol, consuming them doesn’t raise blood cholesterol levels in most people. In fact, eggs appear to modify the size of LDL particles in a way that reduces the risk of heart disease (40).
SUMMARY: Eggs contain less than 1 gram of carbs each and can help keep you full for hours. They’re also high in several nutrients and may help protect eye and heart health.
Coconut oil has unique properties that make it well suited for a ketogenic diet.
To begin with, it contains medium-chain triglycerides (MCTs). Unlike long-chain fats, MCTs are taken up directly by the liver and converted into ketones or used as a rapid source of energy.
In fact, coconut oil has been used to increase ketone levels in people with Alzheimer’s disease and other disorders of the brain and nervous system (41).
The main fatty acid in coconut oil is lauric acid, a slightly longer-chain fat. It has been suggested that coconut oil’s mix of MCTs and lauric acid may promote a sustained level of ketosis (42, 43).
What’s more, coconut oil may help adults with obesity lose weight and belly fat.
In one study, men who ate 2 tablespoons (30 mL) of coconut oil per day lost 1 inch (2.5 cm), on average, from their waistlines without making any other dietary changes (44, 45).
For more information about how to add coconut oil to your diet, read this article.
SUMMARY: Coconut oil is rich in MCTs, which can increase ketone production. In addition, it may increase metabolic rate and promote the loss of weight and belly fat.