Ludwig's team nicely discovers that LC diets increase energy expenditure.
"Introduction
Evidence from animal and human studies shows that biological factors strongly influence body weight.1 With weight loss, hunger increases and energy expenditure decreases—physiological adaptations that defend against long term weight change.2 Genetic factors are known to affect body weight, explaining some of the variance in body mass index (BMI) among people. However, genetic factors cannot explain why the average person today, compared with 40 years ago, seems to be “defending” a much higher body weight.
According to the carbohydrate-insulin model of obesity,3456 the increased ratio of insulin to glucagon concentrations after consumption of a meal with a high glycemic load directs metabolic fuels away from oxidation and toward storage in adipose tissue. This physiological state is hypothesized to increase hunger and food cravings,7 lower energy expenditure, and predispose to weight gain, especially among those with inherently high insulin secretion. The carbohydrate-insulin model offers a physiological mechanism for understanding why obesity rates have increased since the 1970s in the United States, as dietary fats were replaced with high glycemic load foods, including refined grains and added sugars.89
This model has been challenged, primarily owing to lack of evidence from controlled feeding studies.1011121314 A recent meta-analysis reported no meaningful difference in energy expenditure between low carbohydrate and low fat diets.11 The studies included in that analysis, however, were short term (mostly <2 a="" adapting="" at="" carbohydrate="" class="xref-bibr" diet="" fat="" high="" href="https://www.bmj.com/content/363/bmj.k4583#ref-6" id="xref-ref-6-2" least="" low="" of="" or="" process="" seems="" style="background: transparent; border: 0px; box-sizing: border-box; color: #2a6ebb; font-family: inherit; font-size: 10px; font-stretch: inherit; font-style: inherit; font-variant: inherit; font-weight: bold; line-height: inherit; margin: 0px 5px 0px 0px; padding: 0px; text-decoration-line: none; vertical-align: 0.4em;" take="" the="" three="" to="" two="" weeks.="" weeks="" whereas="">6
15161718 For this reason, transient effects of macronutrients cannot be distinguished from long term effects on the basis of existing evidence. We compared the effects of diets varying in carbohydrate to fat ratio on energy expenditure during weight loss maintenance through 20 weeks."Main finding (primary outcome):
"total energy expenditure was significantly greater in participants assigned to a low carbohydrate diet compared with high carbohydrate diet of similar protein content."
Explanation(s)
"ghrelin has been reported to lower energy expenditure and promote fat deposition,6465 providing another mechanistic explanation for our primary outcome."
"Leptin (an adipocyte hormone that signals body energy stores) was also lower in participants assigned to the low carbohydrate diet, suggesting improvement in leptin sensitivity.66Prospective studies have observed that people with the greatest declines in leptin levels after weight loss have the lowest risk for weight regain"
JAMA Intern Med. 2018 Aug 1;178(8):1098-1103. doi: 10.1001/jamainternmed.2018.2933.
The Carbohydrate-Insulin Model of Obesity: Beyond "Calories In, Calories Out".
Abstract
Despite intensive research, the causes of the obesity epidemic remain incompletely understood and conventional calorie-restricted diets continue to lack long-term efficacy. According to the carbohydrate-insulin model (CIM) of obesity, recent increases in the consumption of processed, high-glycemic-load carbohydrates produce hormonal changes that promote calorie deposition in adipose tissue, exacerbate hunger, and lower energy expenditure. Basic and genetic research provides mechanistic evidence in support of the CIM. In animals, dietary composition has been clearly demonstrated to affect metabolism and body composition, independently of calorie intake, consistent with CIM predictions. Meta-analyses of behavioral trials report greater weight loss with reduced-glycemic load vs low-fat diets, though these studies characteristically suffer from poor long-term compliance. Feeding studies have lacked the rigor and duration to test the CIM, but the longest such studies tend to show metabolic advantages for low-glycemic load vs low-fat diets. Beyond the type and amount of carbohydrate consumed, the CIM provides a conceptual framework for understanding how many dietary and nondietary exposures might alter hormones, metabolism, and adipocyte biology in ways that could predispose to obesity. Pending definitive studies, the principles of a low-glycemic load diet offer a practical alternative to the conventional focus on dietary fat and calorie restriction.
The Ludwig's Box of recos
Dietary Recommendations Based on the Carbohydrate-Insulin Model
• Reduce refined grains, potato products, and added sugars—high-glycemic load (GL) carbohydrates with low overall nutritional quality
• Emphasize low-GL carbohydrates, including nonstarchy vegetables, legumes, and nontropical whole fruits(a)
• When consuming grain products, choose whole kernel or traditionally processed alternatives (eg, whole barley, quinoa, traditionally fermented sourdough made from stone ground flour(b)
• Increase nuts, seeds, avocado, olive oil, and other healthful high-fat foods
• Maintain an adequate, but not high, intake of protein, including from plant sources (c)
• For individuals with severe insulin resistance, metabolic syndrome, or type 2 diabetes, restriction of total carbohydrate intake, and replacement with dietary fat, may provide greatest benefit (Feinman RD, Pogozelski WK, Astrup A, et al. Dietary carbohydrate restriction as the first approach in diabetes management: critical review and evidence base. Nutrition. 2015;31(1):1-13.)
(a) Tropical fruits (eg, banana, papaya) have higher GL than temperate fruits (eg, berries, apple).
(b) Because digestion rate is inversely related to particle size, coarsely milled flour has a lower GI than finely-milled modern industrial flours. Long fermentation reduces rapidly digestible carbohydrate content and produces organic acids, thereby lowering GI.
(c) By eliciting glucagon secretion, protein tends to balance carbohydrate from a metabolic perspective. However, large amounts of protein can also raise insulin secretion. Preliminary evidence suggests plant proteins stimulate less insulin, and may have a lesser anabolic effect, than animal proteins (Sanchez A, Hubbard RW. Plasma amino acids and the insulin/glucagon ratio as an explanation for the dietary protein modulation of atherosclerosis. Med Hypotheses. 1991;36(1):27-32.).
And some tech data are in this paper
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6163108/
The recent paper of Ludwig
https://www.bmj.com/content/363/bmj.k4583
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