A low-carb diet limits carbohydrates—such as those found in grains, starchy vegetables, and fruit—and emphasizes foods high in protein and fat. Many types of low-carb diets exist. Each diet has varying restrictions on the types and amounts of carbohydrates you can eat.
Low-carb or no-carb diets can help you avoid sweet and starchy meals like bread, spaghetti, and cereal. Low-carb diets are heavy in protein and lipids and can be a good alternative to calorie counting or gram counting.
The diet isn’t for everyone, though; persons with medical issues like diabetes or high blood pressure, as well as pregnant and nursing women, should talk to their doctor before making major dietary changes.
Even if a lot of indulgences are off the table, folks who have been given the green light to follow a low-carb diet still have some fantastic options.
Low-carb diets have been popular for decades. They used to be highly controversial but have recently gained mainstream acceptance. Low-carb diets tend to cause more weight loss than low-fat diets — at least in the short term.
They also improve numerous health markers, such as blood triglycerides, HDL (good) cholesterol, blood sugar, and blood pressure. However, many types of this eating pattern exist.
Purpose
A low-carb diet is generally used for weight loss. Some low-carb diets may have health benefits beyond weight loss, such as reducing your risk of type 2 diabetes and metabolic syndrome.
Why you might follow a low-carb diet
You might choose to follow a low-carb diet because you:
- Want a diet that restricts certain carbs to help you lose weight
- Want to change your overall eating habits
- Enjoy the types and amounts of foods featured in low-carb diets
Check with your doctor before starting any weight-loss diet, especially if you have any health conditions, such as diabetes or heart disease.
Diet details
A low-carb diet restricts the number of carbohydrates you eat. Carbohydrates are grouped as simple natural (lactose in milk and fructose in fruit), simple refined (table sugar), complex natural (whole grains or beans), and complex refined (white flour).
Common sources of naturally occurring carbohydrates include:
- Grains
- Fruits
- Vegetables
- Milk
- Nuts
- Seeds
- Legumes (beans, lentils, peas)
In general, complex carbohydrates are digested more slowly and they have less effect on blood sugar than refined carbohydrates do. They also provide fiber.
Refined carbohydrates such as sugar or white flour are often added to processed foods. Examples of foods with refined carbohydrates are white bread and pasta, cookies, cakes, candies, and sugar-sweetened sodas and drinks.
Your body uses carbohydrates as its main energy source. During digestion, complex carbs are broken down into simple sugars (glucose) and released into your blood (blood glucose).
Insulin is released to help glucose enter the body’s cells, where it can be used for energy. Extra glucose is stored in the liver and muscles, and some of it is converted to body fat.
A low-carb diet is intended to cause the body to burn stored fat for energy, which leads to weight loss.
Foods for a Low-Carb Diet
A low-carb diet concentrates on proteins and nonstarchy veggies in general. Grain, legumes, fruits, bread, sweets, pasta, and starchy vegetables, as well as nuts and seeds, are often limited in a low-carb diet. Some low-carb diet programs, on the other hand, allow for small portions of fruits, vegetables, and entire grains.
A low-carb diet typically limits carbohydrates to 0.7 to 2 ounces (20 to 57 grams) per day. These carbohydrate levels produce 80 to 240 calories. During the early phase of several low-carb diets, carbs are severely restricted, and subsequently, the quantity of allowable carbs is gradually increased.
The Dietary Guidelines for Americans, on the other hand, suggest that carbohydrates account for 45 to 65 percent of total daily calories.
Here are 8 popular ways to do a low-carb diet.
1. A Typical Low-Carb Diet
The typical low-carb diet does not have a fixed definition.
It is simply referred to as a low-carb or carb-restricted diet.
This eating pattern tends to be lower in carbs and higher in protein than a typical Western diet. It usually emphasizes meats, fish, eggs, nuts, seeds, vegetables, fruits, and healthy fats.
You’re meant to minimize your intake of high-carb foods like grains, potatoes, sugary drinks, and high-sugar junk foods.
The recommended carb intake per day generally depends on your goals and preferences. A common rubric might be something like this:
- Weight: 100–150 g This range is designed for weight maintenance or high-intensity workout on a regular basis. It allows for a lot of fruit as well as starchy meals like potatoes.
- Weight: 50–100 grammes This weight-loss or weight-maintenance spectrum is designed for gradual weight loss or maintenance. There’s plenty of room for fruits and vegetables.
- Approximately 50 grammes. This is designed to help you lose weight quickly. Eat a lot of vegetables, but stick to berries with a low glycemic index (GI).
Your typical low-carb diet is much lower in carbs and higher in protein than a regular diet. The recommended carb intake depends on individual goals and preferences.
2. Ketogenic Diet
The ketogenic diet is a very low-carb, high-fat diet.
The goal of a keto diet is to keep carbs so low that your body goes into a metabolic state called ketosis.
In this state, your insulin levels plummet and your body releases large amounts of fatty acids from its fat stores.
A large portion of these fatty acids is transported to your liver, where they are converted to ketones. Ketones are water-soluble chemicals that can pass the blood-brain barrier to give your brain energy.
Then, rather than relying on carbs, your brain begins to rely heavily on ketones. The minimal quantity of glucose required by your brain can be produced by your body through a process known as gluconeogenesis.
Some variations of this diet also limit protein intake, as too much protein can diminish the number of ketones produced.
The keto diet, which has traditionally been used to treat drug-resistant epilepsy in children, may also be beneficial for other neurological illnesses and metabolic issues such as type 2 diabetes.
It has also become popular for fat loss — even among some bodybuilders — as it’s a very effective way to lose fat and tends to cause a major reduction in appetite. A ketogenic diet involves high-protein, high-fat foods. Carbs are generally limited to fewer than 50 — and sometimes as few as 20–30 — grams per day.
A conventional keto eating pattern is referred to as a standard ketogenic diet (SKD).
However, there are other variations that involve strategically adding carbs:
- Targeted ketogenic diet (TKD). In this version, you add small amounts of carbs around workouts.
- Cyclical ketogenic diet (CKD). This type has you eat a ketogenic diet on most days but switch to a high-carb diet for 1–2 days each week.
3. Low-Carb, High-Fat (LCHF)
LCHF stands for “low-carb, high-fat.” It’s a fairly standard very-low-carb diet but with an even greater emphasis on whole, unprocessed foods.
It focuses mostly on meats, fish and shellfish, eggs, healthy fats, vegetables, dairy products, nuts, and berries.
The recommended carb intake on this diet can range from 20–100 grams per day.
4. Low-Carb Paleo Diet
The paleo diet is currently one of the most popular eating styles in the world. It promotes the consumption of foods that were most likely available during the Paleolithic epoch, prior to the agricultural and industrial revolutions.
Returning to your prehistoric ancestors’ diet, according to paleo advocates, should improve your health because humans allegedly evolved and adapted to consuming such things.
A paleo diet has been shown in several small trials to help people lose weight, lower blood sugar, and improve heart disease risk factors.
A paleo diet is not by definition low-carb, but it often is in practice.
Meats, fish, seafood, eggs, vegetables, fruits, tubers, nuts, and seeds are all highlighted. Processed foods, added sugar, grains, legumes, and dairy products are all prohibited on a paleo diet.
There are several other popular versions, such as the primal blueprint and perfect health diets. All of them tend to be much lower in carbs than a typical Western diet.
5. The Atkins Diet
The Atkins diet is the best-known low-carb eating plan. It involves reducing all high-carb foods while eating as much protein and fat as desired.
The diet is split into four phases:
- Phase 1: Induction. Eat under 20 grams of carbs per day for 2 weeks.
- Phase 2: Balancing. Slowly add more nuts, low-carb vegetables, and fruit.
- Phase 3: Fine-tuning. When you get close to your weight goal, add more carbs until your weight loss becomes slower.
- Phase 4: Maintenance. Eat as many healthy carbs as your body tolerates without gaining back the weight you lost.
The Atkins diet was originally demonized, but current research indicates it’s both safe and effective as long as fiber intake is adequate. This diet is still popular today.
6. Eco-Atkins
The Eco-Atkins diet is essentially a legalized version of the Atkins diet. Gluten, soy, nuts, and plant oils are examples of plant foods and ingredients strong in protein and/or fat.
Carbohydrates account for about 25% of the calories, protein for 30%, and fat for 45 percent. As a result, it contains more carbs than a standard Atkins diet, but far fewer than a usual vegan diet.
An Eco-Atkins diet generated more weight reduction and improved heart disease risk factors than a high-carb vegetarian diet, according to a six-month study.
The Eco-Atkins diet is a vegan adaptation of the Atkins eating plan. While it contains more carbs than a standard Atkins diet, it is still quite low in carbs when compared to most vegetarian and vegan diets.
7. Zero-Carb
Some people prefer to eliminate all carbs from their diet. This is called a zero-carb diet and usually includes only animal foods.
People who follow a zero-carb diet eat meat, fish, eggs, and animal fats like butter and lard. Some of them also add salt and spices.
There are no recent studies that show a zero-carb diet to be safe. Only one case study — from 1930 — exists, in which two men ate nothing but meat and organs for a year but appeared to remain in good health.
A zero-carb diet is lacking in some important nutrients, such as vitamin C and fiber. For this reason, it is generally not recommended.
Some people follow a zero-carb diet, which excludes all plant foods. No quality studies have been done on this eating pattern, and it is usually discouraged.
8. Low-Carb Mediterranean Diet
The Mediterranean diet is very popular, especially among health professionals. It is based on the traditional foods of Mediterranean countries earlier in the 20th century.
Studies show that this diet may help prevent heart disease, breast cancer, and type 2 diabetes. A low-carb Mediterranean eating pattern is modeled after its namesake diet but limits higher-carb foods like whole grains.
Unlike a regular low-carb diet, it emphasizes more fatty fish instead of red meat and more extra virgin olive oil instead of fats like butter.
A low-carb Mediterranean diet may be better for heart disease prevention than other low-carb diets, although this needs to be confirmed in studies.
A low-carb Mediterranean diet is similar to a regular low-carb diet. However, it includes more fish and extra virgin olive oil.
Results
Weight loss
The majority of people may lose weight by limiting calories and increasing physical activity. You must consume 500 to 750 fewer calories each day to lose 1 to 1.5 pounds (0.5 to 0.7 kilogram) per week.
Low-carb diets, especially very low-carb diets, may cause more weight loss in the short term than low-fat diets. However, most studies have concluded that the benefits of a low-carb diet are minimal beyond 12 or 24 months.
Weight loss from low-carb diets may be due to more than just calorie and carb reduction. According to some research, the increased protein and fat in your diet may help you lose weight by making you feel fuller for longer, causing you to eat less.
Other benefits
Low-carb diets that emphasize healthy sources of carbs, fat, and protein may help lower the risk of type 2 diabetes and heart disease. In fact, almost any diet that helps you shed excess weight may improve blood sugar and cholesterol levels, at least temporarily.
Risks
A sudden and drastic reduction in carbs can cause temporary side effects, such as:
- Constipation
- Headache
- Muscle cramps
Severe carbohydrate restriction can cause your body to break down fat into ketones as a source of energy. Ketosis is the term for this state. Side effects of ketosis include poor breath, headaches, weariness, and weakness.
It’s unclear what sort of long-term health consequences a low-carb diet would entail. Long-term carb restriction can lead to vitamin and mineral shortages, as well as gastrointestinal problems.
Some health experts feel that eating a lot of fat and protein from animals may actually increase your risk of heart disease and some malignancies.
Pay attention to the fats and proteins you choose if you adopt a low-carb diet. Saturated and trans fats, such as meat and high-fat dairy products, should be avoided.
Why follow a low-carb diet?
Many people follow low-carb diets on the basis that if the body does not receive extra carbohydrates, it will not store excess fat.
The idea, then, is that the body will burn some of the stored fat rather than the carbs, which will promote fat loss.
Research from 2003 in the New England Journal of Medicine found that people who followed a low-carb diet lost more weight than those on a low-fat diet after 6 months, but not after 12 months.
The study noted that “longer and larger studies are required to determine the long-term safety and efficacy of low-carbohydrate, high-protein, high-fat diets.”
Takeaway
A low-carb diet can have some benefits, including weight loss. With some planning and appropriate substitutions, most people can follow a low-carb diet. However, a low-carb diet may not be the best way to achieve long-term or sustainable health goals.
When following a low-carb diet, it is essential that people eat healthfully and do not overeat certain foods, such as very fatty meats.
People looking to lose weight or considering going on a low-carb diet should speak to their doctor or nutritionist before making any significant changes.
If you’re going to try a low-carb diet, pick a plan that suits your lifestyle, food preferences, and personal health goals.
What works for one person may not work for the next, so the best diet for you is the one you can stick to.