What does the science say about keto?
The page below summarizes the most important scientific evidence behind carbohydrate and keto diets.Although these diets are still considered somewhat controversial by some doctors, there is now high-quality evidence to support weight loss and certain metabolic disorders, such as type 2 diabetes, high blood pressure and some forms of dyslipidemia.
Moreover, the overwhelming evidence also suggests that natural saturated fats are good with regard to health, warnings about the health risks of red meat are based on weak evidence with very low certainty, and low-fat diets do not seem to have special health or weight benefits. Outside of a carbohydrate diet.
A number of meta-analyzes of randomized controlled studies (GMOs), which are considered to be the strongest and best type of evidence, have come to the same conclusion: carbohydrate diets usually perform better than other diets for weight loss for a maximum of two years.
Two recent examples show a greater weight loss in carbohydrate diets compared to low-fat diets in studies that lasted from eight weeks to 24 months:
Plos One 2015: Diet intervention for overweight adults and obesity: comparison of carbohydrate and low-fat diets. A meta analysis
The British Journal of Nutrition 2016: Effects of carbohydrate diets versus low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomized controlled investigations
Carbohydrate does not only lead to more weight loss than other comparable diets, it also results in more fat loss, especially when carbohydrates are limited to 50 grams per day:
Obesity Reviews 2016: Impact of carbohydrate diet on body composition: meta-analysis of randomized controlled studies
The limits of low fat content
An article from 2015 in the magazine The Lancet summarizes all major scientific studies together with low-fat weight loss.
The conclusion? There is no evidence that a low-fat diet helps people lose weight, compared to other dietary advice.
The above metha analyzes even show that people tend to lose significantly more weight if they get food advice, including eating fat to satiety.
The Lancet 2015: Effect of low-fat diet interventions verses other diet interventions on weight change in the long term in adults: a systematic review and meta-analysis.
GMOs show significantly more weight loss in carbohydrate diets than with other diets
According to the last count of the Public Health Collaboration UK There are at least 31 recent GMOs that show significantly better weight loss in carbohydrate diets.
The number of investigations that the opposite shows? Zero.
Here are three of the best GMOs so far:
New England Journal of Medicine 2008: weight loss with a carbohydrate, Mediterranean or low-fat diet
This was a two-year test in which 322 people were randomly assigned to follow a mediterranean diet, a low-fat diet or a carbohydrate diet. By the end of the study, the carbohydrate group had lost the most weight, even though they were allowed to eat as much carbohydrate food as needed to feel satisfied; The other two groups followed a low-calorie diet.
Annals of Internal Medicine 2014: effects of carbohydrate and low-fat diets: a randomized study
In this annual study, 148 people were randomized to consume a low-carbohydrate diet (less than 40 grams of carbohydrates per day) or a low-fat diet (less than 30% energy from fat per day). In addition to the loss of 3.5 kg (7.7 lbs) more than the low-fat group, the carbohydrate group also had larger improvements in high-density lipoprotein (HDL) cholesterol, triglycerides (Tg) and other risk factors for cardiovascular disease.
Journal of the American Medical Association 2007: Comparison of Atkins, Zone, Ornish and Learn diets for weight change and related risk factors at premesopausal overweight women. The research into weight loss from A to Z: a randomized study.
One of the most famous studies at weight loss (often called the A to Z-study) included randomizing premesopausal overweight women to eat either carbohydrate (atkins), moderate carbohydrate (zone), low-fat (ornish). ), or low-calorie, portion-controlled (learn) diet for one year. At the end of the investigation, women in the carbohydrate group had lost twice as much weight (4.7 kg or 10.3 lbs) as the ornish and learn groups and almost three times as much as the women in the zone group .