Low Carbohydrate Diets: Have They Been Researched Adequately?
There have now been more than 70 clinical trials on nearly 7,000 people, including a wide variety of sick and well populations, mainly in the U.S. These studies are compiled in a public database.
Thirty-two of these studies have lasted at least six months
Six trials went on for two years, enough time to demonstrate the lack of any negative side effects.
In virtually every case, the lower-carb, higher-fat diets did as well or better than competing regimens.
The cumulative evidence shows that low-carb diets are safe and effective for combating obesity, highly promising for the treatment of Type 2 diabetes, and they improve most cardiovascular risk factors.
Did the Dietary Guidelines Advisory Committee review this literature?
In 2015, as documented in an article in BMJ, the low-carbohydrate literature was omitted from the Dietary Guidelines Advisory Committee report.
Excerpt: The omitted papers on low-carbohydrate diets include “nine pilot studies, 11 case studies, 19 observational studies, and at least 74 randomised controlled trials, 32 of which lasted six months or longer.” See Table C on BMJ.com for the complete list of studies. A more legible version of this table is available here (Appendix #5).
In 2020, the Dietary Guidelines Advisory Committee formally reviewed the “low-carb” diet but said that it could only find a single study (authored by a member of the Committee).
At the time, there were more than 100 clinical trials on low-carbohydrate or ketogenic diets. The Nutrition Coalition objected to this omission of relevant science in its public comments to USDA.
A well-curated collection of studies on carbohydrate restriction has been done by the Society of Metabolic Health Practitioners.
Their categories include:
This group has also collected a variety of articles by experts in the science and practice of carbohydrate restriction here
Myths and Facts about a low-carbohydrate diet overseen by experts in the field can be found at the following site:
T2 Diabetes and low-carbohydrate/ketogenic diets
The evidence base for low-carbohydrate/ketogenic diets is most advanced for the prevention and even reversal of diabetes. The American Diabetes Association recognized that a ketogenic diet is the best for controlling blood sugar, which is at the heart of combatting T2 diabetes. Official recognition of the ability of very low-carbohydrates to reverse a diagnosis of T2 diabetes are here:
American Diabetes Association Consensus Report:
Definition and Interpretation of Remission in Type 2 Diabetes
https://academic.oup.com/jcem/advance-article/doi/10.1210/clinem/dgab585/6358623
Diabetes UK Position Statement For Healthcare Professionals
Remission In Adults With Type 2 Diabetes
https://www.diabetes.org.uk/professionals/position-statements-reports/statement-remission-type2
Diabetes Australia Position Paper T2 Diabetes Remission
How a low-carbohydrate approach differs from previous theories on obesity
Carbohydrate restriction is based largely upon a new hypothesis about obesity and other metabolic diseases. This hypothesis rejects the idea that obesity can be explained by calories-in-calories-out (CICO) and instead deduces from the evidence that obesity is a hormonal disorder, principally involving the hormone insulin—which is considered the ‘king’ of all hormones for fat deposition.
The carbohydrate-insulin model: a physiological perspective on the obesity pandemic
https://academic.oup.com/ajcn/advance-article/doi/10.1093/ajcn/nqab270/6369073
Should a “low-carbohydrate” diet be one of the USDA-HHS “Dietary Patterns,” recommended to all Americans?
This major review on the low-carbohydrate diet lays out the evidence to argue that a low-carbohydrate diet should be one of the USDA-HHS Dietary Patterns. The authors on this paper are a high-level group, including the country’s senior-most experts and researchers on low-carb and ketogenic diets. This paper provides basic definitions and an up-to-date review of the evidence for low-carb/ketogenic diets for obesity, diabetes, and heart disease.
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