Diet
The Ketogenic Diet
Promises, promises, promises.
Posted August 4, 2019 Reviewed by Hara Estroff Marano
The ketogenic diet is the new darling of our weight-loss culture. It has been touted as offering significant weight reduction as well as delivering numerous health benefits, particularly for diabetes.
The keto diet is a low-carb, high-fat diet that some articles report has been shown to offer health benefits against diabetes, cancer, and Alzheimer’s disease. The premise is that limiting carbohydrates is better than limiting fat in terms of producing weight loss and good health:
- A 2003 study showed that short-term (3-6 months) weight loss was better on a low carbohydrate diet but that the benefit did not hold. At one year, there was no difference between the group on the diet and a group that wasn't.
- In a study of individuals with a BMI of over 43, a low-carbohydrate diet was compared to a low-fat diet. The low-carb dieters lost 12.76 to 31.68 pounds and the low-fat dieters lost 4.18 up to 13.42 pounds. However, the study lasted only six months.
These typify the studies done to “evaluate” different diets. There are many more, but what they all have in common is:
- The amount of weight lost in all the studies is very small for both groups of dieters
- The length of the studies is very short; most are 12 weeks, with some going for six months and a rare few lasting up to a year.
These points are worth reading again. And if you have been a chronic dieter, you know that while it may be easy to lose weight in the short-term, keeping it off is almost impossible, even if you’re highly motivated. In the past you may have blamed yourself: “Why can’t I stay on a diet?” “Why can’t I lose weight when other people can?” There is no reason to blame yourself. But it is time to tell the truth: Diets don't work. They never have and they never will.
The recent DIETFITS (Diet Intervention Examining the Factors Interacting with Treatment Success) study also compared low-fat and low-carb diets and found that both delivered the same weight-loss results, lowering blood sugar and cholesterol. This study included over 600 healthy people who were considered overweight or obese by body mass index (BMI).
In the study, dieters were restricted to either 20 grams of carbs or 20 grams of fat (both are severe restrictions) but were advised to eat as many vegetables as possible, limit processed foods, cook at home, and avoid added sugars, trans fats, and refined carbs. The study participants had 22 classes and access to health educators to teach them behavior modification to reduce emotional eating. Both groups were also encouraged to get 150 minutes of physical activity a week. And both groups lost approximately 12 pounds over the course of one year. DIETFITS researchers felt that both diets were successful because they were healthy and sustainable and because participants received behavioral support.
The keto diet follows in the footsteps of other low-carb diets such as the Paleo and Atkins diets. But it differs in that it encourages followers to stop eating almost all carbohydrates and to eat high levels of fat (over 70 percent of calories consumed) and avoid excess protein. This puts the body into a ketotic state: When it does not have enough glucose (sugar) to burn for energy, the body will burn stored fats instead, leading to a buildup of acids (ketones) in the body. Ketosis can be harmful if excessive, as it can cause ketoacidosis, a condition found in diabetics that can be life-threatening.
But is the keto diet more effective than other diets, for weight loss or for health? In an analysis of over 13 studies—each lasting longer than one year—researchers found that the keto diet resulted in less than two pounds more of weight loss on average than high-carb, low-fat diets (HCLD).
Another analysis of long-term studies of people with Type 2 diabetes did not show that the keto diet improved blood sugar control compared with the HCLD diet. Other studies do not show a significant benefit in lowering cholesterol, especially bad cholesterol, or LDL, and apo-B lipoprotein. Although good (HDL) cholesterol may rise with keto diets, studies have not shown that such an effect translates into lower risk for heart-related diseases.
But why are we still talking about dieting and weight loss at all? It remains clear that dieting is often the trigger for serious life-threatening eating disorders such as anorexia, bulimia, and binge eating disorder. Weight stigma has created a culture in which women and men, children and adults, from all backgrounds suffer over how they look, are bullied for their size, and spend enormous amounts of time, money (over $60 billion), and energy worrying about how they look and what they weigh.
This has created a a culture in which individuals living in larger bodies are afraid to get medical care for fear of medical stigma, with obvious long-term results. Diets have never been shown to be sustainable, especially over the long-term. Nor have they been shown to be effective. Decades of research have not found that dieting is an effective method to lose weight and keep it off. Current research supports the ability to be healthy no matter what your size. That is not to say that you can't make lifestyle changes to improve your health and well-being. But those changes are better when they are not short-term, quick-fix diets that you can't sustain.
Beyond these points, the keto diet poses specific risks related to chronic ketosis and a failure to get enough healthy carbohydrates. Eating whole grains, fruits, and legumes is not the cause of weight gain or health problems. In fact, these products are health-promoting. In over 45 studies, consumption of whole grains was associated with reductions in heart disease, stroke, total cancers, and death from all causes. Documented side effects of the keto diet include constipation, bad breath, muscle cramps, vitamin and mineral deficiencies, headaches, bone fractures, and pancreatitis.
It's important to understand the facts: We don't have a "one size fits all" diet plan that works for every BODY. That is why there are so many diets on the market. If you choose to make lifestyle changes, then, it is best to find a way of eating that you can maintain over years, not months.
How much longer are we willing to risk our lives and our health to be thin? Maybe someday little girls and boys will grow up knowing that bodies come in different sizes and shapes and that all are natural and normal. Maybe we will one day be able to allow people to be the best they can be, recognize that their bodies are none of our business, and put an end to weight stigma.
Maybe we can bury dieting in a time capsule along with dial-up internet, rotary phones, and cars without seat belts. Wouldn't it be great if diets were something our kids' kids never heard of? It's time to make peace with food and with our bodies, eat intuitively, and see ourselves as valuable human beings no matter what size we are.
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References
Joshi S, Ostfeld RJ, McMacken M. The Ketogenic Diet for Obesity and Diabetes—Enthusiasm Outpaces Evidence. JAMA Intern Med. Published online July 15, 2019. doi:10.1001/jamainternmed.2019.2633
Harvard Health newsletter: https://www.health.harvard.edu/blog/weight-loss-for-life-the-dietfits-s…. Accessed 8/5/19.
Yancy WS Jr, et al. A low-carbohydrate, ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia.Trusted Source Annals of Internal Medicine, 2004.
Samaha FF, et al. A low-carbohydrate as compared with a low-fat diet in severe obesity.New England Journal of Medicine, 2003.
Foster GD, et al. A randomized trial of a low-carbohydrate diet for obesity. New England Journal of Medicine, 2003.
Aune D, Keum N, Giovannucci E, et al. Whole grain consumption and risk of cardiovascular disease, cancer, and all cause and cause specific mortality: systematic review and dose-response meta-analysis of prospective studies. BMJ. 2016;353:i2716. doi:10.1136/bmj.i2716
Kwiterovich PO Jr, Vining EP, Pyzik P, Skolasky R Jr, Freeman JM. Effect of a high-fat ketogenic diet on plasma levels of lipids, lipoproteins, and apolipoproteins in children. JAMA. 2003;290(7):912-920. doi:10.1001/jama.290.7.912
Retterstøl K, Svendsen M, Narverud I, Holven KB. Effect of low carbohydrate high fat diet on LDL cholesterol and gene expression in normal-weight, young adults: a randomized controlled study. Atherosclerosis. 2018;279:52-61. doi:10.1016/j.atherosclerosis.2018.10.013
Noto H, Goto A, Tsujimoto T, Noda M. Low-carbohydrate diets and all-cause mortality: a systematic review and meta-analysis of observational studies. PLoS One. 2013;8(1):e55030. doi:10.1371/journal.pone.0055030
Bueno NB, de Melo IS, de Oliveira SL, da Rocha Ataide T. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. Br J Nutr. 2013;110(7):1178-1187. doi:10.1017/S0007114513000548
Hall KD, Chen KY, Guo J, et al. Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men. Am J Clin Nutr. 2016;104(2):324-333. doi:10.3945/ajcn.116.133561
Joshi S, Ostfeld RJ, McMacken M. The Ketogenic Diet for Obesity and Diabetes—Enthusiasm Outpaces Evidence. JAMA Intern Med. Published online July 15, 2019. doi:10.1001/jamainternmed.2019.2633
Harvard Health newsletter: https://www.health.harvard.edu/blog/weight-loss-for-life-the-dietfits-s…. Accessed 8/5/19.
Yancy WS Jr, et al. A low-carbohydrate, ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia.Trusted Source Annals of Internal Medicine, 2004.
Samaha FF, et al. A low-carbohydrate as compared with a low-fat diet in severe obesity.New England Journal of Medicine, 2003.
Foster GD, et al. A randomized trial of a low-carbohydrate diet for obesity. New England Journal of Medicine, 2003.
Aune D, Keum N, Giovannucci E, et al. Whole grain consumption and risk of cardiovascular disease, cancer, and all cause and cause specific mortality: systematic review and dose-response meta-analysis of prospective studies. BMJ. 2016;353:i2716. doi:10.1136/bmj.i2716
Kwiterovich PO Jr, Vining EP, Pyzik P, Skolasky R Jr, Freeman JM. Effect of a high-fat ketogenic diet on plasma levels of lipids, lipoproteins, and apolipoproteins in children. JAMA. 2003;290(7):912-920. doi:10.1001/jama.290.7.912
Retterstøl K, Svendsen M, Narverud I, Holven KB. Effect of low carbohydrate high fat diet on LDL cholesterol and gene expression in normal-weight, young adults: a randomized controlled study. Atherosclerosis. 2018;279:52-61. doi:10.1016/j.atherosclerosis.2018.10.013
Noto H, Goto A, Tsujimoto T, Noda M. Low-carbohydrate diets and all-cause mortality: a systematic review and meta-analysis of observational studies. PLoS One. 2013;8(1):e55030. doi:10.1371/journal.pone.0055030
Bueno NB, de Melo IS, de Oliveira SL, da Rocha Ataide T. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. Br J Nutr. 2013;110(7):1178-1187. doi:10.1017/S0007114513000548
Hall KD, Chen KY, Guo J, et al. Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men. Am J Clin Nutr. 2016;104(2):324-333. doi:10.3945/ajcn.116.133561
Joshi S, Ostfeld RJ, McMacken M. The Ketogenic Diet for Obesity and Diabetes—Enthusiasm Outpaces Evidence. JAMA Intern Med. Published online July 15, 2019. doi:10.1001/jamainternmed.2019.2633
Harvard Health newsletter: https://www.health.harvard.edu/blog/weight-loss-for-life-the-dietfits-s…. Accessed 8/5/19.
Yancy WS Jr, et al. A low-carbohydrate, ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia.Trusted Source Annals of Internal Medicine, 2004.Kwiterovich PO Jr, Vining EP, Pyzik P, Skolasky R Jr, Freeman JM. Effect of a high-fat ketogenic diet on plasma levels of lipids, lipoproteins, and apolipoproteins in children. JAMA. 2003;290(7):912-920. doi:10.1001/jama.290.7.912
Aune D, Keum N, Giovannucci E, et al. Whole grain consumption and risk of cardiovascular disease, cancer, and all cause and cause specific mortality: systematic review and dose-response meta-analysis of prospective studies. BMJ. 2016;353:i2716. doi:10.1136/bmj.i2716Retterstøl K, Svendsen M, Narverud I, Holven KB. Effect of low carbohydrate high fat diet on LDL cholesterol and gene expression in normal-weight, young adults: a randomized controlled study. Atherosclerosis. 2018;279:52-61. doi:10.1016/j.atherosclerosis.2018.10.013