How Safe is No-Carb Diet & What are its Benefits and Drawbacks?

About No-Carb Diet

A no-carb diet is a form of extreme dieting that eliminates nearly all forms of carbohydrates from your diet. It even cuts out fruits, most vegetables, and whole grains. While some studies have indicated that the intake of carbohydrates can help you lose weight and may also have health benefits, but completely cutting out carbs from your diet is an extremely restrictive form of dieting that many experts deem to be unnecessary.1 Here is everything you need to know about a no-carb diet and if such a diet form is safe for you or not.

A no-carb diet involves following a way of eating that completely eliminates all digestible carbohydrates as much as possible. Carbohydrates are the primary source of energy in your body, and they can be found in beans, legumes, grains, fruits, vegetables, yogurt, milk, pasta, baked goods, and bread. This means that someone who is following a no-carb diet must refrain from having most of these foods and instead, opt to eat foods that primarily contain fat or protein, such as eggs, fish, cheese, butter, and oils.

Since there are no strict prescribed guidelines for a no-carb diet, some people choose to have nuts and seeds, high-fat fruits like coconut and avocado, and non-starchy vegetables. Even though these foods contain some amount of carbs, they are rich in fiber, which is why they only have a small number of net carbs or digestible carbs. This can be calculated by subtracting the amount of fiber present in the food from the total number of carbs present.2

A no-carb diet is similar to a ketogenic diet, in which you restrict the intake of carbohydrates to less than just 30 grams per day.3 The ketogenic diet further encourages you to get at least 70 percent or even more of your daily calories from healthy fat.4

However, depending on what all you select to eat, a no-carb diet can prove to be more restrictive than the ketogenic diet.

How Do You Follow Such A Restrictive No-Carb Diet?

There is no doubt that a no-carb diet can be quite restrictive. Many sources recommend that you keep the consumption of net carbs to only 20 to 50 grams per day when you are following a no-carb diet. However, there are no specific protocols or set macronutrient ranges that you need to follow. The bottom line of following a no-carb diet is that you must avoid all high-carb foods.

While following this diet, you have to eliminate refined and whole grains, fruits, milk, baked goods, yogurt, legumes, beans, bread, pasta, starchy vegetables such as corn and peas, and sugar-sweetened drinks. Sugary foods like soft drinks, sweet desserts like chocolate, cake, ice cream, pastry, and candy should also be avoided.5 Sports drinks, fruit juice, and many breakfast cereals are high in added sugars and cannot be included in a no-carb diet. Beans and legumes such as lentils and chickpeas are also high in carbohydrates.

While on a no-carb diet, you can have meat, fish, cheese, eggs, butter, oils, plain coffee or tea, and of course, plenty of water.

If you are not following the diet too restrictively, you can also include nuts and seeds, some non-starchy vegetables, and high-fat fruits like coconut and avocado. These foods are low in net carbs, and you can have them without much worry.

The no-carb diet focuses on limiting one specific macronutrient, which is carbohydrates, and there are no recommendations or specifications on your portion sizes or the daily calorie intake.6

Can A No-Carb Diet Help You Lose Weight?

On a general level, cutting down your intake of carbohydrates can help you lose weight. When you replace carbs with fat and protein, it helps you feel fuller for a longer time and also makes you consume lesser overall calories, thus leading to weight loss.7,8,9

Additionally, very low-carb diets can also help promote rapid weight loss, especially in the first few weeks of starting the diet because of the rapid decrease in water weight. This happens due to the fact that each gram of carbohydrate holds nearly three grams of water in the body. So when you stop consuming carbs, you drop the water weight rapidly.10,11

A 2003 study carried out on 79 obese adult participants discovered that over a period of six months, those who limited their carb intake to less than 30 grams per day were successful in losing around 4 kg (8.8 pounds) more than the participants who limited on the intake of fat to less than 30 percent of their total daily calories.12

Other studies have also found similar results and recommended that following ketogenic or very-low-carb diets for a period of one year or more can result in a sustained weight loss as compared to following low-fat diets.13

Nevertheless, the research done on no-carb diets presents a lot of mixed results. Some studies have also found that low-carb diets are not more effective than other dieting methods for achieving long-term weight loss.14,15

So when you follow a no-carb diet, you are likely to experience weight loss in the short term, but it is essential that you bear these results in mind so that you do not need to eliminate carbohydrates from your diet entirely for achieving weight loss. Even gradually decreasing your intake of carbs and decreasing the overall calorie intake will prove to be helpful in losing weight.

What are the Benefits of a No-Carb Diet?

There are no studies to show that a diet that completely cuts out carbohydrates offers any other health benefits. However, research done on ketogenic and very low-carb diets have shown that they may provide additional health benefits apart from weight loss.

These include:

Good For The Heart: Reducing your intake of carbohydrates can help improve your heart health. Very low carb diets have been found to reduce the levels of blood triglycerides. High levels of triglyceride can increase the risk of heart disease.16,17 For example, a study with 29 men, all of whom were overweight, found that limiting their carb consumption to just ten percent of their daily calories for 12 weeks reduced their triglyceride levels by 39 percent. Other studies have also found that very low-carb diets help increase the levels of good or HDL cholesterol, which is known to protect against heart disease.18 Nevertheless, more research is needed to establish how this works.

Better Control Of Blood Sugar: Completely eliminating or cutting down on carbs, especially sugar and refined carbs, can help you get better control of your blood sugar. This is especially beneficial for people with diabetes.19 Many studies have also found that following a ketogenic and low-carb diet can help lower blood sugar levels. A study carried out over six months ion 49 obese adults who also had type 2 diabetes found that the participants who followed a ketogenic diet had a dramatically lower hemoglobin A1c as compared to those who did not consume a ketogenic diet. A1c is a measure of the average blood sugar in people.20 Decreasing your consumption of carbs can also prevent sudden fluctuations in blood sugar and may help prevent any diabetes-related complications. However, it is not necessary to completely cut out all carbs from your diet. This is because diabetes can also be controlled by being on a higher-carb diet.

Other Benefits of No-Carb Diet

Some of the other health benefits of having a no-carb or very low-carb diet include:

Reduction In Belly Fat: Some amount of research shows that very-low-carb diets can be better than low-fat diets at cutting down belly fat, which is a type of fat linked with many diseases and inflammation in the body.21,22

Lower Blood Pressure: Some research has found that decreasing your carb consumption can help lower your blood pressure.23

Reduced Risk Of Metabolic Syndrome: Reducing your consumption of carbohydrates can help prevents many of the risk factors that are commonly linked with metabolic syndrome, including high blood sugar, belly fat, and high blood pressure.23

What Are The Drawbacks Of A No-Carb Diet?

Following a restrictive diet such as the no-carb diet comes with several drawbacks. Here are some of the more major downsides of this diet.

Lacks Other Nutrients: Following a restrictive no-carb diet means that your diet will be lacking sufficient vitamins and minerals, such as B vitamins, potassium, and vitamin C. The body gets these vitamins and minerals from fruits, vegetables, and other plant-based foods, which are cut out in this format of dieting.24 Also, you are likely to notice an increase in urination from restricting carbs. This may cause deficiencies in potassium and sodium if the diet is continued for a more extended period of time.25,26

It May Lower Your Energy Levels And Cause Constipation: A no-carb diet limits the intake of most vegetables, fruits, whole grains, and beans. Due to this, the diet is very low in fiber. Fiber is one of the most important nutrients the body needs for digestion as it helps maintain the regularity of bowel movement. Due to this, a no-carb diet may cause digestive discomfort and constipation.27,28 Furthermore, carbohydrates are the primary source of energy for the body. So when you follow a no-carb diet, it may lead to fatigue and low energy levels, especially during the beginning days of the diet. The metabolic changes that take place in the body when you eliminate carbohydrates can also lead to nausea, poor mental function, and sleep issues in the short term.

Long-Term Effects Of Such A Highly Restrictive Diet Are Unknown: There are not enough studies to show the long-term effects of such a highly restrictive diet that completely eliminates carbs from your diet. Due to a lack of research, sticking to a no-carb diet for a very long time could have adverse and severe health consequences.29 Furthermore, the no-carb diet not only cuts out the majority of carbs, but it is also very high in fat. Neither is the diet well researched for safety. It is also not right for children, people with cholesterol hyper-responders, pregnant or breastfeeding women, and people with eating disorders.

Summing Up

A no-carb diet focuses on cutting out nearly all carbohydrates and encourages a high consumption of protein and fats. This type of a diet helps in weight loss, boosts your heart health, and also helps control blood pressure and blood sugar. However, in order to experience the benefits of a no-carb diet, you don’t need to cut out all carbs from your diet. If followed for a long time, this diet is known to have certain drawbacks such as lower energy levels, fatigue, and a risk of developing nutrient deficiencies. Due to the limited amount of research available, the long term effect of a no-carb diet on your health remains unknown, which is why such a diet should ideally only be followed for a short time period. Eating a balanced diet that includes a wide variety of foods and avoiding processed foods can be a better way of staying healthy and managing your weight.

References:

  1. Oh, R. and Uppaluri, K.R., 2020. Low carbohydrate diet. In StatPearls [Internet]. StatPearls Publishing.
  2. Freeman, J. and Hayes, C., 2004. “Low-carbohydrate” food facts and fallacies. Diabetes Spectrum, 17(3), pp.137-140.
  3. Freeman, J.M., Kossoff, E.H. and Hartman, A.L., 2007. The ketogenic diet: one decade later. Pediatrics, 119(3), pp.535-543.
  4. McGHEE, B.I.L.L. and Katyal, N., 2001. Avoid unnecessary drug-related carbohydrates for patients consuming the ketogenic diet. Journal of the American Dietetic Association, 101(1), pp.87-101.
  5. Giugliano, D., Maiorino, M.I., Bellastella, G. and Esposito, K., 2018. More sugar? No, thank you! The elusive nature of low carbohydrate diets. Endocrine, 61(3), pp.383-387.
  6. Lyles III, T.E., Desmond, R., Faulk, L.E., Henson, S., Hubbert, K., Heimburger, D.C. and Ard, J.D., 2006. Diet variety based on macronutrient intake and its relationship with body mass index. Medscape General Medicine, 8(3), p.39.
  7. Maljaars, J., Romeyn, E.A., Haddeman, E., Peters, H.P. and Masclee, A.A., 2009. Effect of fat saturation on satiety, hormone release, and food intake. The American journal of clinical nutrition, 89(4), pp.1019-1024.
  8. Paddon-Jones, D., Westman, E., Mattes, R.D., Wolfe, R.R., Astrup, A. and Westerterp-Plantenga, M., 2008. Protein, weight management, and satiety. The American journal of clinical nutrition, 87(5), pp.1558S-1561S.
  9. Layman, D.K., Evans, E.M., Erickson, D., Seyler, J., Weber, J., Bagshaw, D., Griel, A., Psota, T. and Kris-Etherton, P., 2009. A moderate-protein diet produces sustained weight loss and long-term changes in body composition and blood lipids in obese adults. The Journal of nutrition, 139(3), pp.514-521.
  10. Gomez-Arbelaez, D., Bellido, D., Castro, A.I., Ordoñez-Mayan, L., Carreira, J., Galban, C., Martinez-Olmos, M.A., Crujeiras, A.B., Sajoux, I. and Casanueva, F.F., 2017. Body composition changes after very-low-calorie ketogenic diet in obesity evaluated by 3 standardized methods. The Journal of Clinical Endocrinology & Metabolism, 102(2), pp.488-498.
  11. Fernández-Elías, V.E., Ortega, J.F., Nelson, R.K. and Mora-Rodriguez, R., 2015. Relationship between muscle water and glycogen recovery after prolonged exercise in the heat in humans. European journal of applied physiology, 115(9), pp.1919-1926.
  12. Samaha, F.F., Iqbal, N., Seshadri, P., Chicano, K.L., Daily, D.A., McGrory, J., Williams, T., Williams, M., Gracely, E.J. and Stern, L., 2003. A low-carbohydrate as compared with a low-fat diet in severe obesity. New England Journal of Medicine, 348(21), pp.2074-2081.
  13. Bueno, N.B., de Melo, I.S.V., de Oliveira, S.L. and da Rocha Ataide, T., 2013. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. British Journal of Nutrition, 110(7), pp.1178-1187.
  14. Hu, T., Mills, K.T., Yao, L., Demanelis, K., Eloustaz, M., Yancy Jr, W.S., Kelly, T.N., He, J. and Bazzano, L.A., 2012. Effects of low-carbohydrate diets versus low-fat diets on metabolic risk factors: a meta-analysis of randomized controlled clinical trials. American journal of epidemiology, 176(suppl_7), pp.S44-S54.
  15. Foster, G.D., Wyatt, H.R., Hill, J.O., Makris, A.P., Rosenbaum, D.L., Brill, C., Stein, R.I., Mohammed, B.S., Miller, B., Rader, D.J. and Zemel, B., 2010. Weight and metabolic outcomes after 2 years on a low-carbohydrate versus low-fat diet: a randomized trial. Annals of internal medicine, 153(3), pp.147-157.
  16. Wood, R.J., Volek, J.S., Liu, Y., Shachter, N.S., Contois, J.H. and Fernandez, M.L., 2006. Carbohydrate restriction alters lipoprotein metabolism by modifying VLDL, LDL, and HDL subfraction distribution and size in overweight men. The Journal of nutrition, 136(2), pp.384-389.
  17. Budoff, M., 2016. Triglycerides and triglyceride-rich lipoproteins in the causal pathway of cardiovascular disease. The American journal of cardiology, 118(1), pp.138-145.
  18. Brinkworth, G.D., Noakes, M., Buckley, J.D., Keogh, J.B. and Clifton, P.M., 2009. Long-term effects of a very-low-carbohydrate weight loss diet compared with an isocaloric low-fat diet after 12 mo. The American journal of clinical nutrition, 90(1), pp.23-32.
  19. Nathan, D.M. and DCCT/Edic Research Group, 2014. The diabetes control and complications trial/epidemiology of diabetes interventions and complications study at 30 years: overview. Diabetes care, 37(1), pp.9-16.
  20. Westman, E.C., Yancy, W.S., Mavropoulos, J.C., Marquart, M. and McDuffie, J.R., 2008. The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus. Nutrition & metabolism, 5(1), p.36.
  21. Volek, J.S., Sharman, M.J., Gómez, A.L., Judelson, D.A., Rubin, M.R., Watson, G., Sokmen, B., Silvestre, R., French, D.N. and Kraemer, W.J., 2004. Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutrition & metabolism, 1(1), p.13.
  22. Volek, J.S., Phinney, S.D., Forsythe, C.E., Quann, E.E., Wood, R.J., Puglisi, M.J., Kraemer, W.J., Bibus, D.M., Fernandez, M.L. and Feinman, R.D., 2009. Carbohydrate restriction has a more favorable impact on the metabolic syndrome than a low fat diet. Lipids, 44(4), pp.297-309.
  23. Gardner, C.D., Kiazand, A., Alhassan, S., Kim, S., Stafford, R.S., Balise, R.R., Kraemer, H.C. and King, A.C., 2007. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. Jama, 297(9), pp.969-977.
  24. Calton, J.B., 2010. Prevalence of micronutrient deficiency in popular diet plans. Journal of the International Society of Sports Nutrition, 7(1), p.24. Calton, J.B., 2010. Prevalence of micronutrient deficiency in popular diet plans. Journal of the International Society of Sports Nutrition, 7(1), p.24.
  25. Kreitzman, S.N., Coxon, A.Y. and Szaz, K.F., 1992. Glycogen storage: illusions of easy weight loss, excessive weight regain, and distortions in estimates of body composition. The American journal of clinical nutrition, 56(1), pp.292S-293S.
  26. Markland, A.D., Palsson, O., Goode, P.S., Burgio, K.L., Busby-Whitehead, J. and Whitehead, W.E., 2013. Association of low dietary intake of fiber and liquids with constipation: evidence from the National Health and Nutrition Examination Survey (NHANES). The American journal of gastroenterology, 108(5), p.796.
  27. Bergqvist, A.C., 2012. Long-term monitoring of the ketogenic diet: Do’s and Don’ts. Epilepsy research, 100(3), pp.261-266.
  28. Define, H.D.W. and LCDs, C., 2016. Are Low-Carbohydrate Diets Safe and Effective?. The Journal of the American Osteopathic Association, 116(12), p.788.

Was this article helpful?

Yes No
×

Suggestions to Improve the Article

This article contains incorrect information.

This article does not have the information I am looking for.


I Have a Medical Question.

Ask A Doctor Now

If you are facing a medical emergency, call your local emergency services immediately, or visit the nearest ER or urgent care facility
×

Suggestions to Improve the Article

×

How Did This Article Help?

This Article Did Change My Life!


I Have a Medical Question.

Ask A Doctor Now

If you are facing a medical emergency, call your local emergency services immediately, or visit the nearest ER or urgent care facility
×

Thank you for your feedback.