A low-carb diet for beginners

By , medical review by – Updated April 20, 2021

What is low carb?
Foods to eat
Foods to avoid
Meal plans
Printable leaflet
Weight loss
Other benefits
Tips & tricks
Side effects
Start free trial

A low-carb diet is one that limits carbohydrates, primarily found in sugary foods, pasta, and bread. Instead of eating carbs, you eat whole foods including natural proteins, fats, and vegetables.

Studies show that low-carb diets can result in weight loss and improved health markers.¹ These diets have been in common use for decades and are recommended by many doctors.² Best yet, there’s usually no need to count calories or use special products. All you need to do is to eat whole foods that make for a complete, nutritious, and filling diet.³

Learn more about low carb and how to use it for your personal goals here.

Start your FREE 30-day trial!

Get instant access to healthy low-carb and keto meal plans, fast and easy recipes, weight loss advice from medical experts, and so much more. A healthier life starts now with your free trial!

Start FREE trial!

1. What is low carb?

A low-carb diet means that you eat fewer carbohydrates and a higher proportion of fat (with adequate amounts of protein as well). This can also be called a low-carb, high-fat diet (LCHF) or a keto diet.⁴ However, not all low-carb diets result in ketosis.

For decades we’ve been told that fat is detrimental to our health. Meanwhile, low-fat “diet” products, often full of sugar, have flooded supermarket shelves. This has likely been a major mistake, that coincided with the start of the obesity epidemic. While this doesn’t prove causation, it’s clear the low-fat message didn’t prevent the obesity increase, and it is possible it contributed.⁵

Studies now show that there’s no reason to fear natural fats.⁶ Instead, on a low-carb diet fat is your friend. Simply minimize your intake of sugar and starches, make sure you are getting adequate protein, and you can eat all the fat you need to feel satisfied.⁷

When you avoid sugar and starches, your blood sugar tends to stabilize and the levels of the fat-storing hormone insulin drop.⁸ This helps increase fat burning and may make you feel more satiated, thereby naturally reducing food intake and promoting weight loss.⁹

Studies show that a low-carb diet can make it easier to lose weight and to control your blood sugar, among other benefits.¹⁰

The basics

Eat: Meat, fish, eggs, vegetables growing above ground and natural fats (like butter).
Avoid: Sugar and starchy foods (like bread, pasta, rice, beans and potatoes).

Eat when you’re hungry and stop when you’re satisfied. It can be that simple. You do not need to count calories or weigh your food.¹¹ You don’t need low-fat products.¹²

Below are examples of what you could eat, alternatively check out our 1000+ low-carb recipes.

Who should NOT do a strict low-carb diet?

Most people can safely start a low-carb diet.¹³ But in these three situations you may need some preparation or adaptation:

Are you taking medication for diabetes, e.g. insulin? Learn more
Are you taking medication for high blood pressure? Learn more
Are you currently breastfeeding? Learn more

If you’re not in any of these groups, and don’t have other severe chronic medical conditions, you’re good to go! You can read more in our post about contraindications to keto diets.

Disclaimer: While a low-carb diet has many proven benefits, it’s still controversial. The main potential danger regards medications, especially for diabetes, where doses may need to be adapted (see above). Discuss any changes in medication and relevant lifestyle changes with your doctor. Full disclaimer

This guide is written for adults with health issues, including obesity, that could benefit from a low-carb diet.

Controversial topics related to a low-carb diet, and our take on them, include saturated fats, cholesterol, whole grains, red meat and restricting calories for weight loss.

Getting started fast

Do you want to get going with low carb right away? Make it truly simple by signing up for our free two-week low-carb challenge. Or get unlimited meal plans, shopping lists and much else with a free membership trial.

For extra support, join our Facebook community.

In 60 seconds

Does low carb still seem complicated? Check out our visual low-carb in 60 seconds guide

2. What to eat on a low-carb diet

In this section you can learn exactly what to eat on low carb, whether you prefer visual guides, detailed food lists, delicious recipes or a simple get started guide.

Let’s start with a quick visual guide to low carb. Here are the basic low carb food groups you can eat all you like of, until you’re satisfied:

The numbers above are grams of digestible carbs per 100 grams (3.5 ounces). Fiber is not counted, you can eat all the fiber you want.¹⁴

All foods above are below 5% carbs. Sticking to these foods will make it relatively easy to stay on a moderate low-carb diet (less than 50 grams of net carbs per day) or even a strict low-carb diet, with less than 20 grams of net carbs per day.

Detailed low-carb foods list

Try to avoid

Here’s what you should not eat on low carb – foods full of sugar and starch. These foods are much higher in carbs.

The numbers are grams of digestible carbs per 100 grams (3.5 ounces), unless otherwise noted.

Detailed list of foods to avoid

What to drink

What drinks are good on a low-carb diet? Water is perfect, and so is coffee or tea. Preferably use no sweeteners.¹⁵ A modest amount of milk or cream is okay in coffee or tea (but beware of caffe latte!).¹⁶

The occasional glass of wine is fine too.

For more, check out our complete guides to low-carb drinks and low-carb alcohol.

Visual low-carb guides

Here are more detailed visual guides to the amount of carbs in common foods. Is a specific food item low or high in carbs? Click to find out:

Recipes

Browse our over 1,000 delicious low-carb recipes or head over to our 14-day low-carb meal plan for inspiration. You can always find our recipes under “Recipes” in the top menu. Here are a few popular ones:

All low-carb recipes

Meal plans

Use our premium meal planner tool to access tons of weekly meal plans, complete with shopping lists. You can adapt the diet plans to your liking, skipping any meal, choosing how many people you’re cooking for, and the shopping lists adapt. You can even start a new plan from scratch (of from pre-existing ones), tailor them completely and save them.

The meal plans below is available through Diet Doctor Plus. Not a member? Sign up for a FREE 30-day trial to get all our meal plans and many other membership benefits. After the free trial ends, it’s only $9.99/month or $99/year.

Low carb: Easy cooking

Don’t feel like much of a chef but still want to serve and have healthy homemade meals? This is the meal plan for you! Boost your confidence in the kitchen with these delicious and easy-to-make recipes that help you stay below 25 grams of carbs per day.

Full meal plan →

Low carb: Back to basics #1

This is a varied low-carb meal plan filled with delicious meals. If you’re in need of new inspiration or just curious to see what low-carb is all about, this meal plan is for you. It will help you stay below 25 g of carbs per day.

Full meal plan →

Low carb: Budget-friendly #1

This week’s meal plan really has it all! It’s fresh, varied, filling and also affordable. It will help you stay below 25 grams of carbs as well.

Full meal plan →

Check out the meal-planner tool

How low carb is a low-carb diet?

The lower your carbohydrate intake, the more powerful the effects on weight and blood sugar appear to be.¹⁷ For that reason we recommend initially following the dietary advice fairly strictly. When you’re happy with your weight and health, you may carefully try eating more carbs if you want to (although we find many people don’t want to).

Here are three examples of what a low-carb meal can look like, depending on how many carbs you plan to eat per day:

Ketogenic 0-20

Moderate 20-50

Liberal 50-100

A strict low-carb diet is often called a keto or ketogenic diet. It’s not a no-carb diet, but it contains less than 20 grams of carbs per day.

Video course

Here’s an 11-minute video course on how to eat low carb, high fat. Sign up for our free newsletter¹⁸ for instant access to it:

Get started

Keen to get started? Then sign up for our free 2-week low-carb challenge, where you’ll be guided step-by-step through your low-carb journey.

Leaflet

Here’s a leaflet with basic low-carb advice that you may want to print and have around, or give to friends who are curious:

countries3

Low-carb advice in 40 languages

We have written advice on a low-carb diet in 40 languages, including our full Diet Doctor site in Spanish or Swedish.

More languages

Do you have another translation or a significant improvement of one of the earlier ones? E-mail us.

3. Health benefits of a low-carb diet

Why would you consider eating fewer carbs? There are many potential benefits, proven by science and supported by clinical experience, like these:

Lose weight

Most people start eating fewer carbs to lose weight. Studies have shown that low-carb diets are often more effective than other diets.¹⁹ Low carb makes it easier to lose weight without hunger, and without having to count calories.²⁰

According to recent studies, a low-carb diet can even result in burning more calories than other diets.²¹ Learn more

Ready to lose the weight for good?

Our new 10-week program helps you lose weight in a healthy and sustainable way.

Reverse type 2 diabetes²²

Low-carb diets can help reduce or even normalize blood sugar, and thus potentially reverse type 2 diabetes.²³ Since the data to date have focused on very strict low carb diets, we do not know if more liberal low-carb diets will also result in type 2 diabetes reversal. However, as the American Diabetes Association notes, carbohydrate reduction of any level is likely an effective tool for blood sugar control.

Low carb can also be helpful in managing type 1 diabetes.²⁴

A grateful gut

Low carb might help settle a grumpy gut, often reducing symptoms of irritable bowel syndrome such a bloating, gas, diarrhea, cramps, and pain.²⁵ Indigestion, reflux and other digestive issues can sometimes improve, too.²⁶

For some, this is the best part of going low carb and happens usually within the first few days, or first week, of starting the diet.²⁷ Learn more

Reduce sugar cravings

Are you struggling to stay away from sweet foods, even though you try to eat them in “moderation”? Many people do.²⁸

A low-carb diet can often reduce and sometimes even eliminate cravings for sweets ²⁹

Bonus benefits

Weight loss, shrinking fat stores, lower blood sugar, improved mental clarity, and a calmer digestive system are the most frequently cited benefits of low-carb eating.³⁰

But some people experience even more improvements, some of which can be life-changing: lower blood pressure and other improvements in risk factors for heart disease,³¹ less acne and better skin,³² fewer migraines,³³ possibly improved mental health symptoms, better fertility,³⁴ and more.³⁵

The links below share more inspiring testimonials and scientific research about potential low-carb benefits.

All low-carb benefits

Success stories

We’ve been sent over 600 amazing low-carb success stories, and get more all the time. Here are a few, and links to all of them sorted by categories:

Eight years of zero-carb eating and "have never looked or felt better!"
A low-carb diet: Maintaining a 70-pound weight loss for five years
"I have so much energy"

4. Low-carb tips and guides

To make a low-carb diet truly simple and enjoyable requires a few new skills. For example, how do you cook low-carb breakfasts that you love? How do you eat more healthy fats? And what’s important to think about when dining out?

Here are all the guides you need.

Breakfast

Breakfast is a great time to eat low carb. Who doesn’t love bacon and eggs? In the unlikely event that you answered “I”, there are even great options with no eggs at all.

Another strong option is to just have a cup of coffee, as many people get less hungry on a low-carb, high-fat diet and may not need breakfast at all.³⁶ This can save you plenty of time.

There are many other options – both delicious and fast

Meals

So, What’s for lunch and dinner on a low-carb diet? You could have mouth-watering, delicious dishes full of meat, fish, chicken, vegetables and full-fat sauces. The options are nearly limitless as you will see by our variety of recipes and meal plans.

Check out our recipes to learn to cook amazing low-carb meals

Instead of potatoes, pasta and rice

Who needs starchy sides when you can have cauliflower mash or cauliflower rice instead? Not to mention butter-fried green cabbage, yum!

In short, we can show you plenty of great low-carb alternatives that are both tasty and healthy. You may even end up liking them better than their carb-heavy predecessors.

Eating out

It’s very possible to eat low carb even when leaving your house, for example at restaurants. Just avoid starchy foods and ask for some extra natural fat (e.g. olive oil or butter).

This guide helps you with tips for fast food, other restaurants, buffets and for when you eat at a friend’s house

Snacks

You probably don’t need to snack as much on a low-carb diet, as you’ll likely feel satisfied longer.³⁷

However, if you want something right away you could have cheese, nuts, cold cuts or even an egg. There are lots of amazing options

Bread

Do you have a hard time living without bread?

You may not have to. Just be aware that there are good and bad low-carb bread options. Spoiler: you’ll probably want to stay away from “low-carb” bread from the grocery store! Here’s why, and what to do instead

How to eat more fat

Fat can be both satiating and an amazing flavor enhancer. But how do you get enough of it in your diet? And how much fat should you really eat? Hint: enough to feel satisfied and not hungry.

Learn all about it in this guide

Avoid “low-carb” junk food

Many who are eating a low-carb diet can get seduced by creatively marketed “low carb” products — cakes, cookies, candies, chocolate, pastas, breads, ice cream and other substitute foods.

Unfortunately this rarely ends well, especially not for weight loss. These products are usually lacking beneficial nutrients and are often higher in carbs than their labels imply. We recommend avoiding them entirely if possible. Learn more

How to make low carb cheap

A low-carb diet doesn’t have to be expensive. In this guide, you’ll learn how to make it cheap.

With a little planning and preparation you could save a ton of money

Low-carb cheating

Is it a good thing to occasionally stray from on a low-carb diet? That depends. And it’s worth thinking about what’s right for you. Learn more

More guides

Do you want more low-carb guides? We have more low-carb guides!

All low-carb guides

5. Potential side effects on a low-carb diet

If you stop eating sugar and starch cold turkey (recommended) you may experience some side effects as your body adjusts. For some people these side effects are mild, while others find the transition more difficult. It usually lasts a few days, up to two weeks, and there are ways to minimize it (see below).³⁸

Another option is to decrease the intake of carbohydrates slowly, over a few weeks, to minimize side effects. But the “Nike way” (Just Do It) may be the best choice for most people. Removing most sugar and starch often results in several pounds lost on the scale within a few days. This may be mostly fluids, but it can still be great for motivation.³⁹

Here are side effects that may occur when you suddenly start a strict low-carb diet.

Induction flu

By far the most common short-term side effect is called the induction flu. It’s what makes some people feel really poorly for a few days (up to a week) after starting low carb.

Here are common symptoms:⁴⁰

Headache
Fatigue
Dizziness
Nausea
Irritability

These side effects rapidly subside as your body adapts and your fat burning increases. Within a week or two, they are usually gone.⁴¹

The primary reason for this may be that carbohydrate-rich foods can increase water retention in your body.⁴² When you stop eating high-carb foods you’ll lose excess water through your kidneys. This can result in dehydration and a lack of salt during the first week, before the body has adapted, resulting in the symptoms above.

You can minimize the induction flu by drinking more fluids and by at least temporarily increasing your salt intake. A good option is to drink a cup of bouillon/broth one or two times a day. This usually keeps the induction flu minor or even non-existant.⁴³

Alternatively, drink a few extra glasses of water and put more salt on your food.

Learn more about induction flu and how to treat it

Other common issues on low carb

Beyond the induction flu, there are six more relatively common side effects on a low-carb diet. It seems like many of them can also be mostly avoided by getting enough fluid and salt.⁴⁴

There are also more things you can do to minimize any problems, click to read more if you’ve experienced one of these issues:

Reduced physical performance

Reduced tolerance to alcohol

Less common issues

These are less commonly noticed issues, that generally only affect a minority of people:

Potential danger when breastfeeding

All low-carb side effects and how to cure them

Low-carb controversies

Beyond the mostly transient side effects that may occur on a low-carb diet (see above) there are many controversies, misunderstandings and a few pure myths that simply don’t hold up to closer scrutiny. For example, your brain is supposed to stop working unless you eat carbs. We’ll, that’s simply wrong.⁴⁵

Read all about these topics on our low-carb controversies page, or choose a specific topic below:

6. Learn more

Here’s the sixth and final section of this low-carb page. Do you want to truly understand low carb, and get answers to your remaining questions? Or do you want extra inspiration for yourself or for people you’re trying to help?

Find it here, and start becoming a low-carb expert.

Low-carb TV

Get insight, enjoyment and inspiration to help you succeed, from the top low-carb channel on the planet.

Select from hundreds of awesome videos, and we’re adding 2-4 more new ones every week. Enjoy! The service is only available for members, but we offer a free trial. Join free for a month

How low carb works

What are you designed to eat, and why can sugar and starch be a problem? Essentially, how does a low-carb diet work?

Learn how low carb works

Scientific studies on low carb

Questions and answers

Are you having problems on low carb? Are you not losing weight like you want to? How many carbs should you eat?

Get answers to your low-carb questions

For extra support, join our Facebook community.

Why fat is your friend

A lot of people still fear natural fat. But really, the whole idea that we should fear fat is based on low quality science that does not support the broad sweeping conclusion. Recent research and many open-minded experts now agree.⁴⁶

Upcoming low-carb events

Do you want to learn much more, and meet experts and other people who are interested in low carb? Here’s a current list of upcoming low-carb conferences and other events.

The Food Revolution

Do you want a summary of the ongoing food revolution? From failed low-fat diets and an epidemic of obesity and diabetes, through a growing realization of our mistakes, and towards a potential health revolution.

Watch this talk by Dr. Andreas Eenfeldt, the founder of Diet Doctor:

Diet Doctor Eat — Try our amazing keto recipe app

What’s the best keto recipe app for iPhone and Android? Diet Doctor Eat! Download for free, and enjoy our entire recipe collection in a beautiful and easy phone-friendly format.

You’ve reached the end of this page (congratulations!). Keep reading about what to eat on a low-carb diet

Start your FREE 30-day trial!

Get instant access to healthy low-carb and keto meal plans, fast and easy recipes, weight loss advice from medical experts, and so much more. A healthier life starts now with your free trial!

Start FREE trial!

Don’t miss

Low-carb foods

14-day low-carb diet meal plan

Scientific studies show that compared to other diets, low carb is generally more effective for weight loss and certain health markers:

PLOS ONE 2015: Dietary intervention for overweight and obese adults: comparison of low-carbohydrate and low-fat diets. A meta-analysis [strong evidence]

Here are two of the top studies showing more weight loss and improvements in health markers on low carb:
- New England Journal of Medicine 2008: Weight loss with a low-carbohydrate, mediterranean, or low-fat diet [moderate evidence]
- Annals of Internal Medicine 2014: Effects of low-carbohydrate and low-fat diets: a randomized trial [moderate evidence]
For many more studies on the topic, have a look at our low-carb science page.

Hundreds of success stories: Low-carb success stories ↩
Hundreds of medical doctors recommending a low-carb or ketogenic diet ↩
While calories count, you probably don’t have to count them for good results. Low-carb diets tend to result in more weight loss, even though most studies of it do not advocate counting calories:

British Journal of Nutrition 2016: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomized controlled trials. [strong evidence for more weight loss]

The reason could be that people’s appetite tends to be suppressed on low-carb diets so that people can eat fewer calories and still be satisfied:

Obesity Reviews 2014: Do ketogenic diets really suppress appetite? A systematic review and meta-analysis [strong evidence]

Another potential cause may be that under some circumstances people tend to burn more calories on a low-carb diet:

British Medical Journal 2018: Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial [moderate evidence]

Learn more here: Should you count calories on a low-carb or keto diet? ↩
A keto diet is a common name for a very strict low-carb diet, containing very few carbohydrates, generally below 20 grams of net carbs per day. This usually results in a metabolic state called “ketosis”, hence the name.

Learn more about a keto diet

A low-carb diet is always relatively low in carbohydrates. But not necessarily so low that people end up in ketosis. Here at Diet Doctor we consider anything up to 100 grams of net carbohydrates per day a low-carb diet. ↩
BMC Public Health 2019:
Systematic review of the impact of nutrition claims related to fat, sugar and energy content on food choices and energy intake [review of nonrandomized studies, weak evidence]

Journal of Marketing research 2006: Can “Low-Fat” Nutrition Labels Lead to Obesity? [nonscientific study ungraded]
↩
While this is still controversial, repeated modern systematic reviews find no benefit from avoiding saturated fats, and minimal if any benefit from replacing them with unsaturated fats:
- Open Heart 2016: Evidence from randomized controlled trials does not support current dietary fat guidelines: a systematic review and meta-analysis [strong evidence]
- Nutrition Journal 2017: The effect of replacing saturated fat with mostly n-6 polyunsaturated fat on coronary heart disease: a meta-analysis of randomized controlled trials [strong evidence]
Further modern reviews on related topics:

Annals of Internal Medicine 2016: Association of dietary, circulating, and supplement fatty acids with coronary risk: a systematic review and meta-analysis [strong evidence for lack of obvious health effects of emphasizing “fat quality”]

PLOS ONE 2016: Is butter back? A systematic review and meta-analysis of butter consumption and risk of cardiovascular disease, diabetes, and total mortality [strong evidence for a lack of major health issues related to butter consumption]

Learn more about why low-fat diets may have been a major mistake

More studies ↩
Low-carb diets tend to result in more weight loss, even though most studies of it do not advocate counting calories:

British Journal of Nutrition 2016: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomised controlled trials. [strong evidence for more weight loss]

The reason could be that people tend to feel less hungry on low-carb diets, so that people can eat fewer calories and still be satisfied:

Obesity Reviews 2014: Do ketogenic diets really suppress appetite? A systematic review and meta-analysis [strong evidence]

Another potential cause may be that under some circumstances people tend to burn more calories on a low-carb diet:

British Medical Journal 2018: Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial [moderate evidence] ↩
Insulin levels drop significantly on a low-carb diet, as described here: Yes, a low-carb diet greatly lowers your insulin

The following RCTs also provide supporting evidence:

American Journal of Clinical Nutrition 2010: Lack of suppression of circulating free fatty acids and hypercholesterolemia during weight loss on a high-fat, low-carbohydrate diet. [randomized trial; moderate evidence]

Nutrition and Metabolism 2006: Comparison of isocaloric very low carbohydrate/high saturated fat and high carbohydrate/low saturated fat diets on body composition and cardiovascular risk. [randomized trial; moderate evidence]

Learn more about insulin ↩
Low-carb diets tend to result in more weight loss than other diets:

British Journal of Nutrition 2016: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomised controlled trials. [strong evidence for more weight loss]

Increased satiety and reduced hunger:

Obesity Reviews 2014: Do ketogenic diets really suppress appetite? A systematic review and meta-analysis [strong evidence]

Increased fat burning:

British Medical Journal 2018: Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial [moderate evidence]

Hormones play a role in regulating our weight. Eating fewer carbohydrates lowers blood glucose, which in turn lowers insulin, also known as the fat-storing hormone. This makes it easier to access and burn excess body fat, without hunger or calorie counting.

Learn how low carb works

Scientific studies on low carb ↩
PLOS ONE 2015: Dietary intervention for overweight and obese adults: comparison of low-carbohydrate and low-fat diets. A meta-analysis [strong evidence]

Diabetes Research and Clinical Practice 2018: Effect of dietary carbohydrate restriction on glycemic control in adults with diabetes: A systematic review and meta-analysis [strong evidence]

More studies ↩
While calories count, you probably don’t have to count them for good results. This has been demonstrated in studies (see below).

Learn more here: Should you count calories on a low-carb or keto diet?

Low-carb diets tend to result in more weight loss, even though most studies of it do not advocate counting calories:

British Journal of Nutrition 2016: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomised controlled trials. [strong evidence for more weight loss]

The reason could be that people’s appetite tends to be somewhat suppressed on low-carb diets, so that people can eat fewer calories and still be satisfied:

Obesity Reviews 2014: Do ketogenic diets really suppress appetite? A systematic review and meta-analysis [strong evidence]

Another potential cause may be that under some circumstances people tend to burn more calories on a low-carb diet:

British Medical Journal 2018: Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial [moderate evidence] ↩
There are many reasons to avoid low-fat products:

Open Heart 2016: Evidence from randomised controlled trials does not support current dietary fat guidelines: a systematic review and meta-analysis [systematic review of randomized trials; strong evidence]

The low-fat diet: “a massive public health failure”

The problem with low-fat products

Journal of the American Medical Association 2016: Lowering the bar on the low-fat diet ↩
The main fear about low-carb, higher-fat diets has been potentially increasing the risk of heart disease. But modern studies do not support that theory, and many risk factors even improve on low carb:
- British Journal of Nutrition 2016: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomised controlled trials. [strong evidence for improved risk factors]
- Obesity reviews 2012: Systematic review and meta‐analysis of clinical trials of the effects of low carbohydrate diets on cardiovascular risk factors [strong evidence for improved risk factors]
- Circulation 2010: Dietary intervention to reverse carotid atherosclerosis [moderate evidence for a reduction in atherosclerosis]
- Cardiovascular Diabetology 2018: Cardiovascular disease risk factor responses to a type 2 diabetes care model including nutritional ketosis induced by sustained carbohydrate restriction at 1 year: an open label, non-randomized, controlled study [nonrandomized trial; weak evidence]
↩
Fiber does not directly affect blood sugar levels, though it can indirectly slow down the absorption of digestible carbohydrates that you eat.

Fiber can have both beneficial and some potential negative effects on gut health, but it usually has no major impact on the effects of a low-carb diet. ↩
Even zero-calorie sweeteners may have some negative effects, including maintaining a preference for sweet tastes, and increased reward, potentially increasing the risk of overeating and even food addiction. This is mainly based on clinical experience [weak evidence].

There is one RCT showing weight loss from avoiding artificial sweeteners:

The American Journal of Clinical Nutrition 2015: Effects on weight loss in adults of replacing diet beverages with water during a hypoenergetic diet: a randomised, 24-wk clinical trial [moderate evidence]

For more, check out our guide to low-carb sweeteners or have a look at these further references:
- International Journal of Obesity 2017: Effects of aspartame-, monk fruit-, stevia- and sucrose-sweetened beverages on postprandial glucose, insulin and energy intake [randomized trial; moderate evidence]
- Physiology & Behavior 2016: Recent studies of the effects of sugars on brain systems involved in energy balance and reward: relevance to low-calorie sweeteners [overview article; ungraded]
- PLOS Medicine 2017: Artificially sweetened beverages and the response to the global obesity crisis [overview article; ungraded]
↩
A modest amount could for example be a tablespoon. But these add up quickly if you drink multiple cups per day.

Also avoid other coffee drinks with lots of added milk or sugar. ↩
This is mainly based on the consistent experience of experienced practitioners, and stories from people trying different levels of carb restriction [weak evidence].

One trial showed that diets of 20-grams and 50-grams of carbs equally helped healthy volunteers maintain ketosis. However, we don’t know if the same is true for people with obesity, insulin resistance or diabetes. In addition, there is not yet an RCT that tests the health benefits of two low-carb diets of varying strictness head-to-head. But RCTs of strict low-carb diets appear to often show better results, compared to RCTs of more moderate or liberal low-carb diets.

Read more about RCTs of low-carb interventions for weight loss ↩
Our weekly newsletter gives you the top low-carb news, recipes and tips without ads or industry influence. Your email is kept 100% private. To cancel press “unsubscribe” at the bottom of any newsletter. ↩
British Journal of Nutrition 2016: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomised controlled trials. [strong evidence for more weight loss] ↩
Scientific studies show that compared to other diets, low-carb or keto diets are often more effective for weight loss (even when many of the studies do not recommend counting calories):

PLOS ONE 2015: Dietary intervention for overweight and obese adults: comparison of low-carbohydrate and low-fat diets. A meta-analysis [strong evidence]

Low-carb diets reduce feelings of hunger:

Obesity Reviews 2014: Do ketogenic diets really suppress appetite? A systematic review and meta-analysis [strong evidence] ↩
Low-carb diets might increase metabolism – potentially increasing fat burning – by between 200 and 500 calories per day:

British Medical Journal 2018: Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomised trial [moderate evidence] Learn more ↩
Some disagree with the use of the word “reverse” when it comes to type 2 diabetes. The concern is that it may imply the disease is completely gone, never to return. At Diet Doctor, we use the term “reverse” to indicate that the diagnosis of diabetes is no longer present at that moment. However, we acknowledge that the diagnosis of diabetes will likely return if a patient goes back to their prior high-carb eating habits. Therefore, “reverse” does not imply a forever cure. ↩
Diabetes Research and Clinical Practice 2018: Effect of dietary carbohydrate restriction on glycemic control in adults with diabetes: A systematic review and meta-analysis [strong evidence]

BMJ Open Diabetes Research and Care 2017: Systematic review and meta-analysis of dietary carbohydrate restriction in patients with type 2 diabetes [strong evidence]

A non-randomized trial with risk of financial bias shows remarkable effectiveness at reversing type 2 diabetes:

Diabetes Therapy 2018: Effectiveness and safety of a novel care model for the management of type 2 diabetes at 1 year: An open-label, non-randomized, controlled study [nonrandomized trial; weak evidence]

Frontiers in Endocrinology 2019: Long-term effects of a novel continuous remote care intervention including nutritional ketosis for the management of type 2 diabetes: a 2-year non-randomized clinical trial [nonrandomized trial; weak evidence]

Full list of studies on low carb for diabetes ↩
There is still a shortage of high-quality studies, but what exists is promising, sometimes showing remarkable improvements.

PLOS ONE 2018: Low-carbohydrate diets for type 1 diabetes mellitus: A systematic review [strong evidence for promising early results, but a shortage of high-quality RCTs]

Pediatrics 2018: Management of type 1 diabetes with a very low–carbohydrate diet [very weak evidence for an exceptionally strong positive effect]

Asia Pacific Journal of Clinical Nutrition 2016: A randomised trial of the feasibility of a low carbohydrate diet vs standard carbohydrate counting in adults with type 1 diabetes taking body weight into account [moderate evidence for a positive effect, though a very small study]

Stories of people trying low carb for type 1 diabetes
↩
This is based on clinical experience of low-carb practitioners and was unanimously agreed upon by our low-carb expert panel. You can learn more about our panel here [weak evidence]

This small non-randomized intervention trial show promising effects:

Clinical Gastroenterology and Hepatology 2009: A very low-carbohydrate diet improves symptoms and quality of life in diarrhea-predominant irritable bowel syndrome [weak evidence]

A low-carb diet is a low FODMAP diet, and the latter has scientific support for improving IBS symptoms:

Journal of Gastroenterology and Hepatology 2017: The evidence base for efficacy of the low FODMAP diet in irritable bowel syndrome: is it ready for prime time as a first-line therapy? [moderate evidence] ↩
Digestive Diseases and Sciences 2006: A very low-carbohydrate diet improves gastroesophageal reflux and its symptoms.[weak evidence]

Alimentary Pharmacology and Therapeutics 2016: Dietary carbohydrate intake, insulin resistance and gastro‐oesophageal reflux disease: a pilot study in European‐ and African‐American obese women [weak evidence]

Learn more ↩
This is based on clinical experience of low-carb practitioners and was unanimously agreed upon by our low-carb expert panel. You can learn more about our panel here [weak evidence] ↩
Like anything else that can be highly rewarding – gambling, drugs, etc. – sweet processed foods can result in behavior resembling an addiction. Note that it’s likely not just a specific substance – e.g. sugar – that is the culprit leading to addiction, but rather the full rewarding experience of certain foods, e.g. sweet chocolate.

Here are a few papers discussing this issue.

Childhood Obesity 2017: Food addiction: a barrier for effective weight management for obese adolescents [non-controlled study; weak evidence]

Current Opinion in Clinical Nutrition and Metabolic Care 2013: Sugar addiction: pushing the drug-sugar analogy to the limit [animal and human summary evidence; weak evidence]

Neuroscience & Biobehavioral Reviews 2008: Evidence for sugar addiction: behavioral and neurochemical effects of intermittent, excessive sugar intake [animal studies; very weak evidence]
↩
This is most likely caused by avoiding the foods that can cause a food addiction, most of which are processed foods full of sugar and/or other refined carbohydrates.

Just like with any other addiction, avoiding the cause is a necessary part of slowly reducing the addiction. A person who is addicted to alcohol normally can’t consume alcohol “in moderation” and be successful. The same thing is likely true for any addiction.

Nutrients 2019: Changes in Food Cravings and Eating Behavior after a Dietary Carbohydrate Restriction Intervention Trial [nonrandomized study, weak evidence]

In the case of low-carb diets, it may also be that the hunger-reducing effect can be helpful:

Obesity Reviews 2014: Do ketogenic diets really suppress appetite? A systematic review and meta-analysis [strong evidence] ↩
Most of these potential benefits have strong or moderate scientific support (see references higher up on the page).

Regarding mental clarity, this is something that is often reported by people on a strict low-carb diet [very weak evidence].

The scientific support for increased mental clarity is not strong. Here are references showing minor signs of improvements:
- Journal of the Association of Nurses for AIDS Care 2019: Cognitive Effects of a Ketogenic Diet on Neurocognitive Impairment in Adults Aging With HIV: A Pilot Study. [randomized trial; moderate evidence]
↩
British Journal of Nutrition 2016: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomised controlled trials. [strong evidence]

Annals of Internal Medicine 2010: Weight and metabolic outcomes after 2 years on a low-carbohydrate versus low-fat diet [moderate evidence]

Cardiovascular Diabetology 2018: Cardiovascular disease risk factor responses to a type 2 diabetes care model including nutritional ketosis induced by sustained carbohydrate restriction at 1 year: an open label, non-randomized, controlled study [weak evidence] ↩
American Journal of Clinical Nutrition 2007: A low-glycemic-load diet improves symptoms in acne vulgaris patients: a randomized controlled trial [moderate evidence]

This review article discusses the theory and the science behind this potential effect:

Skin Pharmacology and Physiology 2012: Nutrition and acne: therapeutic potential of ketogenic diets ↩
This is a commonly reported positive effect from people who start a ketogenic diet. Here are some stories. [very weak evidence]

There are two promising early studies so far:

European Journal of Neurology 2015: Migraine improvement during short lasting ketogenesis: a proof-of-concept study. [randomized trial; moderate evidence]

Journal of Headache and Pain 2016: Cortical functional correlates of responsiveness to short-lasting preventive intervention with ketogenic diet in migraine: a multimodal evoked potentials study. [non-controlled study; weak evidence] ↩
Nutrients 2017: The effect of low carbohydrate diets on fertility hormones and outcomes in overweight and obese women: a systematic review [strong evidence]

There is likely a positive effect of low-carb diets on PCOS, a common hormonal problem for women that can impact fertility.

Studies on low carb and PCOS ↩
European Journal of Clinical Nutrition 2013: Beyond weight loss: a review of the therapeutic uses of very-low-carbohydrate (ketogenic) diets ↩
Obesity Reviews 2014: Do ketogenic diets really suppress appetite? A systematic review and meta-analysis [strong evidence]

Contrary to older misconceptions, a recent meta-analysis of randomized clinical trials found that people assigned to skip breakfast ate less overall and lost more weight than those assigned to eat breakfast daily:

British Medical Journal 2019: Effect of breakfast on weight and energy intake: systematic review and meta-analysis of randomised controlled trials [strong evidence] ↩
This is a very common experience from people trying a low-carb diet, and it’s supported by science:

Obesity Reviews 2014: Do ketogenic diets really suppress appetite? A systematic review and meta-analysis [strong evidence]

The appetite-reducing effect might be partially mediated by certain hormonal factors:

European Journal of Clinical Nutrition 2013: Ketosis and appetite-mediating nutrients and hormones after weight loss ↩
This is based on clinical experience of low-carb practitioners and was unanimously agreed upon by our low-carb expert panel. You can learn more about our panel here [weak evidence].

There was also a small RCT in healthy volunteers demonstratiung side effects lasting up to 17 days.

Nutrition X 2019: Effects of differing levels of carbohydrate restriction on the achievement of nutritional ketosis, mood, and symptoms of carbohydrate withdrawal in healthy adults: A randomized clinical trial [randomized trial; moderate evidence]
↩
This is based on clinical experience of low-carb practitioners and was unanimously agreed upon by our low-carb expert panel. You can learn more about our panel here [weak evidence]. ↩
Nutrition X 2019: Effects of differing levels of carbohydrate restriction on the achievement of nutritional ketosis, mood, and symptoms of carbohydrate withdrawal in healthy adults: A randomized clinical trial [randomized trial; moderate evidence] ↩
This is based on clinical experience of low-carb practitioners and was unanimously agreed upon by our low-carb expert panel. You can learn more about our panel here [weak evidence].

This was also demonstrated in a small pilot study with healthy subjects.
Nutrition X 2019: Effects of differing levels of carbohydrate restriction on the achievement of nutritional ketosis, mood, and symptoms of carbohydrate withdrawal in healthy adults: A randomized clinical trial [randomized trial; moderate evidence]
↩
International Journal of Hypertension 2011: Insulin resistance, obesity, hypertension, and renal sodium transport [overview article; ungraded] ↩
This is mainly based on the consistent experience of experienced clinicians [weak evidence]. But there’s also some support from this study that found only minor increases in side effects, while advising participants to drink bouillon:

Nutrition & Metabolism 2008: The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus [moderate evidence] ↩
E.g. one or two cups of bouillon per day.

The evidence for this is mainly based on the consistent experience of experienced clinicians [weak evidence]. But there’s also some support from this study that found only minor increases in side effects, while advising participants to drink bouillon:

Nutrition & Metabolism 2008: The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus [moderate evidence] ↩
On a strict low-carb diet, the liver produces ketones from fat, that become an effective fuel for the brain. Learn more about it in this overview article:

Critical Care 2011: Clinical review: ketones and brain injury [overview article; ungraded]
↩
Open Heart 2016: Evidence from randomised controlled trials does not support current dietary fat guidelines: a systematic review and meta-analysis [strong evidence]

Learn more about why low-fat diets may have been a major mistake ↩

A low-carb diet for beginners

Start your FREE 30-day trial!

1. What is low carb?

The basics

Who should NOT do a strict low-carb diet?

Getting started fast

In 60 seconds

2. What to eat on a low-carb diet

Try to avoid

What to drink

Visual low-carb guides

Recipes

Meal plans

Low carb: Easy cooking

Low carb: Back to basics #1

Low carb: Budget-friendly #1

How low carb is a low-carb diet?

Video course

Get started

Leaflet

Low-carb advice in 40 languages

3. Health benefits of a low-carb diet

Lose weight

Ready to lose the weight for good?

Reverse type 2 diabetes22

A grateful gut

Reduce sugar cravings

Bonus benefits

Success stories

Top success story videos

More

4. Low-carb tips and guides

Breakfast

Meals

Instead of potatoes, pasta and rice

Eating out

Snacks

Bread

How to eat more fat

Avoid “low-carb” junk food

How to make low carb cheap

Low-carb cheating

More guides

Top videos about low-carb basics

5. Potential side effects on a low-carb diet

Induction flu

Other common issues on low carb

Less common issues

Low-carb controversies

6. Learn more

Low-carb TV

How low carb works

Questions and answers

Why fat is your friend

Upcoming low-carb events

The Food Revolution

Diet Doctor Eat — Try our amazing keto recipe app

Next

Start your FREE 30-day trial!

More

How to lose weight

600+ success stories

Low-carb recipes

Don’t miss

Reverse type 2 diabetes²²