Low-Carb Diet Overview

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There are different reasons for choosing to follow a low-carb diet. Perhaps you've heard that cutting carbs is a fast way to lose weight. Certainly, some people feel more energized or perform better when they eat less starch. Others choose to eat a lower carbohydrate diet to help control blood sugars. But carbs are a necessary macronutrient and there is no diet that is right for everyone.

When followed in the short term, low-carbohydrate diets can yield health benefits. Some people may improve their blood sugars and lose weight following this type of eating plan. But there is no clear definition of what a low-carb diet is and studies investigating its long-term safety and efficacy have yielded mixed results.

A low-carb diet could also be problematic for those with a history of restrictive or disordered eating. If you're wondering if a low-carb diet could be right for you, learn more about how, what's involved, and the steps you'll need to take to get started.

What Are Carbohydrates?

Carbohydrates are a nutrient made up of simple sugars (monosaccharides). When these sugars bind together, they form complex molecules. Depending on how the sugars are combined, they can create disaccharides (double sugars like lactose and sucrose), oligosaccharides (short-chain sugars called glycoproteins and glycolipids), and polysaccharides (long-chain sugars, like starch and cellulose).

When you eat carbohydrates like starch or sugar, your body converts them into glucose for fuel. When your body consumes more carbohydrates than it can burn for fuel, it packages them up and stores the rest as fat. Some research has suggested that the type of carbohydrates consumed is more important than the quantity. That is, some carbohydrate-rich foods get broken down more quickly than others.

When this happens, it causes a sudden spike in blood sugar. We measure these spikes using a system called the glycemic index (GI).

What Is a Low Carb Diet?

Many of us eat more carbohydrates than our bodies need. People with conditions like diabetes may be in danger if they eat more carbohydrates than their body can handle, as it will affect their blood sugar levels.

A low-carb diet aims to help you reduce how many carbohydrates you eat, which can be helpful if you're hoping to lose weight, better control your blood sugar, or just want to improve your overall health. It's important to note that a low-carb diet isn't equal to a no-carb diet.

Your body requires carbohydrates to function properly. On a low-carb diet, you'll work toward maintaining an intake of carbohydrates balanced to your body's needs. That means avoiding being deprived of carbs or eating them in excess.

If you've ever been out to dinner and a friend refuses the bread basket because they're "watching their carbs," you're already aware of the prevailing attitudes about carbs in our society. But these beliefs about carbs don't just oversimplify the science; they also fail to capture what a low-carb diet is really about. While it's true that starchy foods such as bread, pasta, and potatoes are carbohydrates, not all carbohydrates are starch.

Health Benefits

Most everyone will benefit from reducing excess sugar intake. Major health organizations recommend limiting the added sugars to several teaspoons per day.

The extent to which people will benefit from greater carbohydrate reduction has to do with how well our individual bodies handle carbohydrate, as sugars and starches in our food all end up as sugars in our bodies.

People with certain types of health concerns are more likely to benefit from low-carb diets than other dietary approaches. Health conditions that may benefit from low-carb diets include:

  • Fatty liver disease
  • Hypertriglyceridemia
  • Insulin resistance
  • Metabolic syndrome
  • Prediabetes
  • Type 2 diabetes

If you are taking medication to lower blood glucose or blood pressure, check with your doctor before making changes to your diet. When you lose weight, the dose of certain medications you take may need to be readjusted.

Different Low-Carb Diet Plans

The term "low-carb diet" actually refers to many different dietary plans, but all these plans have one shared characteristic: the modification or reduction in added starches and refined carbohydrates. Low-carb diets are sometimes called reduced-carbohydrate or low-glycemic diets.

The term "low-carb" may be defined in different ways. Sometimes, it refers to slightly less carbohydrate than is generally recommended. In other diets, the term may represent a very low allowance of daily carbohydrates.

There are different variations to a low carb diet. Before starting any new diet plan, always consult with your health care provider and consider getting a referral to a registered dietian. Diving into a low carbohydrate eating plan without guidance from a registered dietitian can result in negative effects. It's always best to have your meal plan tailored to your needs to prevent any adverse effects.

The three approaches to eating low carb include:

Total Carb Reduction

Using a low-carb food pyramid as a guide, you can put together meals based on a balanced diet of low-carb vegetables, low-sugar fruits, healthy fats, and ample proteins (ideally under 35 percent of your daily caloric intake).

Individualized Carb Intake

Each of us has a different degree of carbohydrate tolerance. Some plans are centered around helping you find out what yours is and adjusting your diet accordingly. This includes the Atkins Diet, the South Beach Diet, and the Paleo Diet.

Ketogenic Diet

One of the more popular plans is a ketogenic diet, a very low-carb diet that causes the body to use fat for energy rather than glucose. This puts the body into a state referred to as keto-adaptation in which the burning of fat can increase stamina and vitality.

How to Start a Low Carb Diet

First, particularly if you are managing a health condition, it's wise to involve your healthcare team in your decision to go low-carb. It's a good idea to have your doctor "sign off" on whether or not a low-carb eating plan is appropriate for you, monitor how your carb intake is affecting your overall health, and provide guidance along the way.

When embarking on a low-carb diet, start by making incremental changes, focusing first on reducing the less-healthy carbs in your diet.

Find Low Carb Foods

Most low-carb diets include lots of non-starchy vegetables; meats and/or eggs, and other sources of proteinlow-sugar fruits (such as berries); dairy foods (such as cheese and yogurt); nuts and seeds; and foods with healthy fats.

There are some nice "extras" available to complement these foods, such as low-carb tortillas and low-carb condiments. You might be surprised at the wide variety of meals with low-carb ingredients—even baked goods and desserts.


6 Low-Sugar Fruits for Low-Carb Diets

If you don't eat meat, you can follow a low-carb vegetarian diet. These diets use non-meat protein sources like nuts and beans.

Avoid added sugars and other refined carbohydrates. The "no white food" rule— which involves the elimination of sugar, white flour, and white rice from the diet—can be a straightforward way to start. One of the most direct ways to reduce your carb intake is to eliminating sugary drinks.

Adjust Your Appetite

Once you are eating the right amount of carbohydrate for you, you'll likely notice a change in your appetite. In general, you should practice eating when you're hungry and stopping when you're satisfied.

When you're hungry, reach for foods that are in sync with the plan you've chosen. However, keep in mind that just because a food is allowed on a low-carb diet, it doesn't mean you can overindulge (cheese is a good example).

Know Your Limits

The amount of carbohydrates we need will depend on our age and activity. As we age, our calorie needs become lower and therefore we likely don't need as many carbohydrates as we did when we were younger. Sometimes eating too many carbohydrates can result in blood sugar ups and downs which can affect energy. If you eat a high carbohydrate diet and are at risk of pre-diabetes, continuing to eat a high carbohydrate meal plan may result in pre-diabetes or insulin resistance.

Regardless of the low carb diet plan you choose, its always important to listen to your body. Adjust your diet if you are feeling tired or sluggish or if you are not achieving the results you are looking for. Consulting with a dietitian will help you find your way.

Plan for an Adjustment Period

Low-carb eating may be entirely new territory for you. It's helpful to be aware of common mistakes people make on a low-carb diet, including avoiding fat and forgetting fiber (constipation is one potential side effect of low-carb diets).

It may also be a new territory for your body. Many people who embark on a low-carb way of eating speak of "carb crash" which can include symptoms like jitteriness, lethargy, or just not quite feeling like themselves. Knowing what to expect during your first low-carb week can help you prepare physically and mentally.

Seek Support

Viewing a low-carb diet as a temporary measure or trend can set you up for a negative experience. Instead, try viewing your choice as being a long-term strategy for improving your health—one that can be changed, and will evolve, as you do.

Making lifestyle changes is never easy, particularly if you have people or habits that sway you from reaching the goals you've set for yourself. To prevent this, surround yourself with people who understand your goals and may even join you in making the same changes.

This is especially important during the first three months of adopting a low-carb diet (or any lifestyle change, for that matter). After the first few months, your new lifestyle practices will begin to settle in as a routine.

If you don't have immediate support, join an online forum or support group where you can share your challenges and celebrate your achievements. Ongoing positive reinforcement is essential to the long-term success of any lifestyle change.

A Word From Verywell

Once your body adapts to your new way of eating, you'll likely experience more benefits than you expected. For example, people who have long suffered from heartburn often find dietary changes can lessen or even help cure the condition. Others find they have more energy, can concentrate better, or think more clearly.

Knowledge is power. The more you know about your options (and yourself) before you begin a low-carb diet, the better prepared you'll be to make changes and stick to them.

5 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Chambers ES, Byrne CS, Frost G. Carbohydrate and human health: is it all about quality? The Lancet. 2019;393(10170):384-386. doi:10.1016/S0140-6736(18)32468-1

  3. Glycemic Index and Diabetes. American Diabetes Association

  4. Sugar 101.  American Heart Association

  5. Hu FB. Are refined carbohydrates worse than saturated fat?. Am J Clin Nutr. 2010;91(6):1541-2. doi:10.3945/ajcn.2010.29622

Additional Reading

By Laura Dolson
Laura Dolson is a health and food writer who develops low-carb and gluten-free recipes for home cooks.