Scientists Weigh In

[Michael]

gizmodo-com.cdn.ampproject.org/v/s/gizmodo.com/should-you-be-eating-a-high-fat-low-carb-diet-like-ket-1830482079/amp?amp_js_v=a2&_gsa=1#referrer=https%3A%2F%2Fwww.google.com&_tf=From%20%251%24s&share=https%3A%2F%2Fgizmodo.com%2Fshould-you-be-eating-a-high-fat-low-carb-diet-like-ket-1830482079

[mr potatohead]

From the source for the article in the lead post, "Science" magazine, a publication of the American Association for the Advancement of Science (AAAS):

Science 16 Nov 2018:
Vol. 362, Issue 6416, pp. 764-770
DOI: 10.1126/science.aau2096

David S. Ludwig, Walter C. Willett, Jeff S. Volek, Marian L. Neuhouser

LINK to Science magazine article

Conclusion
The optimal proportion of carbohydrate to fat in the diet for obesity treatment and chronic disease prevention has been a topic of debate for decades, often generating more heat than light (101). Of course, any meaningful assessment of a diet’s impact on health must extend far beyond macronutrient quantity, to include the myriad qualitative aspects of food and food combinations that influence hormonal response, gene expression, and metabolic pathways. Further complicating this issue is the likelihood that inherent or acquired biological differences among individuals or populations, especially related to glucose homeostasis, affect response to specific diets.

Unfortunately, the national nutrition research agenda has not been adequate to address important areas of controversy (Box 1). Currently, the United States invests a fraction of a cent on nutrition research for each dollar spent on treatment of diet-related chronic disease. All too often, scientific results in this field have been ambiguous: Macronutrient feeding studies have been too short and too small to distinguish transient from chronic effects; many behavioral trials have lacked the intensity to produce meaningful differences between dietary treatment groups; and observational studies can be affected by confounding, inability to distinguish cause and effect, and other methodological problems. Furthermore, despite promising preliminary data, few major studies of a ketogenic diet in the treatment of diabetes have been conducted. Additional questions related to sustainability for the individual (whether people can realistically remain on prescribed diets) and for the environment (the impacts of specific dietary patterns on natural resources and climate change) require more study. Given the enormous human and economic toll of diet-related disease, high-quality research into key controversies should be given priority.

Box 1
Current controversies.
1. Do diets with various carbohydrate-to-fat proportions affect body composition (ratio of fat to lean tissue) independently of energy intake? Do they affect energy expenditure independently of body weight?

2. Do ketogenic diets provide metabolic benefits beyond those of moderate carbohydrate restriction? Can they help with prevention or treatment of cardiometabolic disease?

3. What are the optimal amounts of specific fatty acids (saturated, monounsaturated, polyunsaturated) in the context of a very-low-carbohydrate diet?

4. What is the relative importance for cardiovascular disease of the amounts of LDL cholesterol, HDL cholesterol, and triglycerides in the blood, or of lipoprotein particle size, for persons on diets with distinct fat-to-carbohydrate ratios? Are other biomarkers of equivalent or greater importance?

5. What are the effects of dietary fat amount and quality across the lifespan on risk of neurodegenerative, pulmonary, and other diseases that have not been well studied?

6. What are the long-term efficacies of diets with different carbohydrate-to-fat proportions in chronic disease prevention and treatment under optimal intervention conditions (designed to maximize dietary compliance)?

7. What behavioral and environmental interventions can maximize long-term dietary compliance?

8. What individual genetic and phenotypic factors predict long-term beneficial outcomes on diets with various fat-to-carbohydrate compositions? Can this knowledge inform personalized nutrition, with translation to prevention and treatment?

9. How does variation in the carbohydrate-to-fat ratio and in sources of dietary fat affect the affordability andenvironmental sustainability of diets?
The incomplete nature of research notwithstanding, data from multiple lines of investigation have led to important areas of consensus (Box 2). Current evidence indicates that no specific carbohydrate-to-fat ratio in the diet is best for the general population. Nor do all diets, and calorie sources, have similar metabolic effects in everyone. With attention to diet quality—and specifically a focus on reducing processed foods, including sugar and refined grains—many people do relatively well with substantial variation in macronutrient composition (102). For the rapidly rising proportion of the population with severe metabolic dysfunction or diabetes, a more specific dietary prescription may be needed.

The incomplete nature of research notwithstanding, data from multiple lines of investigation have led to important areas of consensus (Box 2). Current evidence indicates that no specific carbohydrate-to-fat ratio in the diet is best for the general population. Nor do all diets, and calorie sources, have similar metabolic effects in everyone. With attention to diet quality—and specifically a focus on reducing processed foods, including sugar and refined grains—many people do relatively well with substantial variation in macronutrient composition (102). For the rapidly rising proportion of the population with severe metabolic dysfunction or diabetes, a more specific dietary prescription may be needed.

Box 2
Points of consensus.
1. With a focus on nutrient quality, good health and low chronic disease risk can be achieved for many people on diets with a broad range of carbohydrate-to-fat ratios. (*see note below)

2. Replacement of saturated fat with naturally occurring unsaturated fats provides health benefits for the general population. Industrially produced trans fats are harmful and should be eliminated. The metabolism of saturated fat may differ on carbohydrate-restricted diets, an issue that requires study.

3. Replacement of highly processed carbohydrates (including refined grains, potato products, and free sugars) with unprocessed carbohydrates (nonstarchy vegetables, whole fruits, legumes, and whole or minimally processed grains) provides health benefits.

4. Biological factors appear to influence responses to diets of differing macronutrient composition. People with relatively normal insulin sensitivity and β cell function may do well on diets with a wide range of carbohydrate-to-fat ratios; those with insulin resistance, hypersecretion of insulin, or glucose intolerance may benefit from a lower-carbohydrate, higher-fat diet.

5. A ketogenic diet (*ketogenic does not equal low carb?) may confer particular metabolic benefits for some people with abnormal carbohydrate metabolism, a possibility that requires long-term study.

6. Well-formulated low-carbohydrate, high-fat diets do not require high intakes of protein or animal products. Reduced carbohydrate consumption can be achieved by substituting grains, starchy vegetables, and sugars with nonhydrogenated plant oils, nuts, seeds, avocado, and other high-fat plant foods.

7. There is broad agreement regarding the fundamental components of a healthful diet that can serve to inform policy, clinical management, and individual dietary choice. Nonetheless, important questions relevant to the epidemics of diet-related chronic disease remain. Greater investment in nutrition research should assume a high priority.

*NOTE: From an earlier post, it appears that "ketosis" can be achieved with most any combination of macros, including nearly 100% carbs - as long as a calorie deficit is maintained. So, according to this, "ketogenic" would equal "caloric restriction" of nutrient dense macros.

[mr potatohead]

About the AAAS:

American Association for the Advancement of Science (AAAS), the largest general scientific society in the United States. It was founded in 1847 in Boston, Mass., by a number of geologists and naturalists and held its first meeting in Philadelphia, Pa., in 1848. Its goals are to further the work of scientists, to facilitate cooperation among them, to improve the effectiveness of science in the promotion of human welfare, and to increase public understanding and appreciation of the role of science in human progress. By the late 20th century the AAAS had more than 130,000 individual members. The organization represents all the major branches of science and is divided into sections representing most of them. The AAAS conducts conferences and meetings in coordination with its formal affiliates, which include nearly 300 scientific societies, professional organizations, and state and city scientific academies.

The headquarters of the AAAS are in Washington, D.C. Its major publications are the weekly journal Science; Science Education News, published six times a year; Science Books & Films, which appears nine times a year; and a series of symposium volumes.

[TexasRanger]

I've got Dr. Ludwig's publication, Always Hungry, and learned quite a bit from it regarding insulin resistance, etc.

One of the key points and discoveries he has been recognized for is the relationship between metabolism and processed carbohydrates and even poor rankings on the glycemic index and glycemic load studies.  What he found is the more processed the food, the impact (literally) on your metabolism gets more and more detrimental.  More specifically, a person's metabolism slows down in proportion to the amount of processed foods, the continual exposure, etc., etc.  And, if you're insulin resistant the issue compounds itself.

This varies by age, health of the individual, etc., but, things like exercise won't overcome a bad diet (as we all know).

Dr. Ford Brewer, MD, formerly of Johns Hopkins University, has a wealth information on his YouTube videos and has discussed this topic and alos notes if you're over 45 or 50, your risk of become insulin resistant increases dramatically each year.  Brewer found he was insulin resistant despite running several marathons a year, etc., and through his experiment of one recognized the carbs in his diet along with a possible low beta cell count contributed to this. (And the guy's clearly in great condition, based on his videos.) He's since cut processed and other carbs due to his insulin resistance.

One other consideration: a number of MDs are now saying there's a 1:1 between heart disease, cancer and insulin resistance.  Reading the science, PubMed papers, etc., it makes even more sense and explains why cholesterol is NOT the bad guy -- it is a response to the issues created by insulin resistance.  Get rid of insulin resistance, your cholesterol levels should drop -- less inflammation et al.  (Of course other factors affect cholesterol -- illness, inflammation from other foods such as those high in SFAs, etc.)

Kind of rambled all over from the original topic -- apologies. 

[Michael]

I find all this interesting Texas and Mikey, Thanks! If I understood the main concept of the article it's everyone can't thrive on the same diet? Texas, the guy Brewer does he eat a ketogenic diet?