The ketogenic diet is a diet that is high in fat, moderate in protein, and very low in carbohydrates. Carbohydrates are the body’s primary energy source, but on a strict ketogenic diet, only about 5% to 10% of the energy consumed comes from carbohydrates.
By reducing carbohydrates, the body enters a metabolic state known as ketosis. In ketosis, the body breaks down stored fat into molecules called ketone bodies to provide energy, rather than relying on circulating blood sugar from food. Once ketosis is achieved, most cells utilize ketone bodies as a source of energy until carbohydrate consumption resumes.
The ketogenic diet was historically utilized solely in clinical settings to decrease seizures in children affected by epilepsy.
Emily Stone, M.S., RD, founder of Eat to Enjoy, states that the diet’s efficacy in addressing various neurological conditions, cancer, diabetes, PCOS (polycystic ovary syndrome), obesity, high cholesterol, and cardiovascular disease has piqued considerable interest. Additionally, individuals adopt the keto diet as a means to achieve weight loss.
When following a ketogenic diet, it may be puzzling to determine which foods to consume, despite knowing that keto entails a very low-carb, high-fat, moderate-protein approach. Our guide will assist you in identifying foods that are suitable to include in your diet, foods that should be restricted, and foods that can be consumed in moderation.
Unsweetened coffee and tea
Plain coffee and tea have no carbohydrates, fat, or protein, making them suitable for the keto diet. Additionally, a research study published in the European Journal of Preventative Cardiology in 2022 reveals that consuming 2-3 cups of coffee daily decreases the chances of developing cardiovascular disease.
Tea, which is abundant in antioxidants, contains lower levels of caffeine compared to coffee. Additionally, it possesses numerous health-enhancing qualities that have the potential to shield against cancer, prevent elevated blood pressure and blood sugar levels, and enhance cognitive functioning.
Dark chocolate and cocoa powder
When checking the label on these, consider that the quantity of carbohydrates varies based on the type and quantity consumed. Cocoa is often referred to as a “superfruit” due to its high antioxidant content, while dark chocolate possesses flavanols that may lower blood pressure and promote healthy arteries, as suggested in a 2018 review of the Journal of the American College of Nutrition.
Berries
Berries possess a high amount of antioxidants that diminish inflammation and safeguard against illness. They contain minimal carbs and have a substantial fiber content.
The carbohydrate content of certain berries in a half cup serving is as follows:
- Blackberries: 3 g net carbs (7 g total carbs)
- Blueberries: 9 g net carbs (11 g total carbs)
- Raspberries: 3 g net carbs (7 g total carbs)
- Strawberries: 3 g net carbs (6 g total carbs)
Eggs
Eggs have a high protein content and are rich in B vitamins, minerals, and antioxidants. In terms of nutrients, two large eggs have no carbohydrates and provide more than 12 g of protein.
According to a study published in the International Journal of Environmental Research and Public Health in 2020, eggs have been found to promote feelings of fullness. Additionally, a study published in Clinical Nutrition in the same year has shown that eggs also contain antioxidants like lutein and zeaxanthin, which aid in preserving eye health.
Avocados
When considering options, select heart-healthy fats such as avocados, as they are rich in both monounsaturated fat and potassium, a mineral that is deficient in the diets of many Americans.
According to a study published in The American Journal of Clinical Nutrition in 2018, replacing animal fats with plant fats such as avocados can improve cholesterol and triglyceride levels. Half of a medium-sized avocado consists of approximately 6 g of total carbohydrates, with 4.5 g being fiber, and contains 360 milligrams of potassium, which meets approximately 8% of your daily requirements.
Cheese
Cheese is a suitable choice for the ketogenic diet due to its lack of carbohydrates and high fat content. Additionally, it provides a good source of protein and calcium. However, it’s essential to be aware that a 1-ounce slice of Cheddar cheese contains approximately 5 g of saturated fat, a quantity that the American Heart Association advises restricting in order to decrease the likelihood of heart disease.
Seafood
Fish and shellfish are suitable for a keto diet due to their low carbohydrate content. Not only are salmon and other fish almost carb-free, but they also provide essential nutrients like B vitamins, potassium, and selenium. Nevertheless, the carbohydrate content of shellfish varies depending on the type. Shrimp and most crabs are carb-free, but oysters and octopus contain carbs. While consuming these foods is still possible on a keto diet, it is vital to meticulously monitor their carbohydrate intake to stay within the desired range.
Salmon, sardines, mackerel, and other fatty fish contain high amounts of omega-3 fats, which are linked to reduced insulin levels and improved insulin sensitivity in overweight individuals or those with obesity.
The American Heart Association advises adults aged 18 and above to consume 8-10 ounces of seafood each week, as it contributes to better brain health and lowers the likelihood of diseases.
Meat and poultry
Fresh meat and poultry, which are rich in B vitamins and essential minerals, are staple foods in the keto diet due to their zero carbohydrate content. Additionally, they provide a valuable source of top-notch protein that can aid in maintaining muscle mass while following a very low carbohydrate diet.
A study conducted on older women demonstrated that a diet rich in fatty meat resulted in an 8% increase in HDL (good) cholesterol levels compared to a low fat, high carbohydrate diet. It is recommended to opt for grass-fed meat whenever feasible, as it contains higher amounts of omega-3 fats and conjugated linoleic acid (CLA) in comparison to meat sourced from grain-fed animals.
Plain Greek yogurt and cottage cheese
Plain Greek yogurt and cottage cheese are regarded as healthy, protein-rich food options. Despite containing a certain amount of carbohydrates, their consumption in moderate amounts is acceptable within the keto diet. Studies indicate that both yogurt and cottage cheese can effectively curb hunger and provoke sensations of satiety.
Both options can be enjoyed as a delicious snack individually, yet you have the option to mix them with chopped nuts, cinnamon, or other spices to whip up a speedy keto delight.
Cream and half-and-half
The fatty part of fresh milk is used to make cream, which is separated during milk processing. In contrast, half-and-half contains equal parts of cream and whole milk. Both cream and half-and-half are low in carbohydrates and high in fat, making them suitable for a keto diet.
Cream and half-and-half, like other fatty dairy products, contain CLA, which can potentially aid in fat loss. Nonetheless, it is advisable to consume cream and half-and-half in moderation.
The 2021 dietary guidance from the American Heart Association recommends restricting the consumption of foods that contain high amounts of saturated fat. Substituting animal and dairy fats with plant-based sources of fat or polyunsaturated fats is associated with a reduced risk of cardiovascular disease and stroke.
Although some studies have proposed that there may not be a strong connection between high fat dairy products and heart disease, others indicate that consuming a moderate amount of high fat dairy could potentially decrease the risk of heart attack and stroke. Nonetheless, the evidence currently available does not provide a conclusive answer.
Whether cream or half-and-half is the preferred option for coffee or as a keto substitute in cooking can be a controversial topic, contingent upon various factors, such as the extent of food processing.
Unsweetened plant-based milk
There are various kinds of plant-based milk that are suitable for a keto diet, such as soy, almond, and coconut milk. Opt for unsweetened varieties as the sweetened options contain excessive amounts of sugar and are not suitable for keto.
In order to adhere to the principles of a keto diet, it is advisable to avoid oat milk as its carb content, even when unsweetened, is too high.
Green leafy vegetables
Green leafy veggies are extremely low in carbs, making them excellent for keto. They’re also rich sources of vitamins, minerals, and antioxidants. In particular, dark leafy greens like spinach, kale, and collard greens are packed with vitamin K and iron.
Here are some leafy greens that are keto-friendly, as they add bulk to your meals without significantly increasing the carb count. Moreover, herbs like oregano and rosemary contribute abundant flavor while containing minimal carbs.
- Salad greens: lettuce, baby spinach, arugula, escarole, and frisee
- Cooking greens: bok choy, collard greens, mustard greens, kale, spinach, Swiss chard, and cabbage
- Herbs: thyme, sage, mint, oregano, dill, parsley, cilantro, basil, rosemary, and lemongrass
Peppers
There are different types of peppers available, all of which are suitable for the keto diet. Despite being classified as fruits, they are used like vegetables when cooking.
Small hot peppers can contribute spiciness to various recipes, and jalapeños are particularly suitable for preparing appetizers that align with a keto-friendly diet. In multiple dishes, you can utilize larger yet mild peppers including bell peppers and poblanos, or alternatively, stuff them to create delectable main courses with reduced carbohydrates. Additionally, peppers are an abundant source of vitamin C. As an example, a single bell pepper supplies 107% of the daily value (DV) for vitamin C.
Summer squash
Summer squashes, including yellow squash and zucchini, are known for their versatility and their low carbohydrate content. It should be noted that zucchini is particularly favored within the keto diet. The utilization of a spiralizer allows one to create zucchini noodles, which serve as a fantastic alternative to traditional pasta or noodles.
Zucchini can be grated to serve as a rice substitute or included in baked goods with no impact on taste. Another option is to thinly slice the zucchini using a mandoline, then combine it with olive oil, salt, and pepper to have it as a chilled salad.
High fat veggies
Avocados and olives are distinct from other vegetables due to their relatively high fat content, despite being classified as fruits. Additionally, these fruits provide fiber and have a low net carb count. Oleuropein, the primary antioxidant found in olives, possesses anti-inflammatory properties and has the potential to safeguard your cells against harm.
Furthermore, a study discovered that individuals who consumed an avocado on a daily basis observed enhancements in factors that pose a risk to heart health, such as decreased levels of LDL (bad) cholesterol.