Hello and welcome. I'm Dr George Lundberg and this is At Large at Medscape

A "battle royale" is being waged in the fields of clinical and epidemiologic nutrition, and investigational and clinical endocrinology. During the week of August 20, 2018, I tossed (and took) a figurative grenade at virtually the entire medical and scientific establishment, confessing my complicity and laying out the case that "it's not the fat"—dietary saturated and unsaturated fats (possibly excluding trans fats) and cholesterol—that is the principal causative factor in the pathogenesis of arteriosclerotic cardiovascular disease, stroke, and myocardial infarction. As much as we can in biologic science, in which knowledge tends to shift, I consider that a settled issue. Obviously, many disagree and will adhere to their institutionalized dietary fat-blaming dogma.

By pure happenstance, in that same week, Stanford's one-man wrecking crew, John Ioannidis, scored a direct howitzer hit on the entire field of nutritional epidemiologic research in JAMA,[1] trashing much of the published research and demanding fundamental reform and a complete field rejuvenation. Thank you, John.

The next and current big battle is over diabetes mellitus, insulin resistance, and obesity. How are they related? What can be done to stem the worldwide epidemic and prevent it from worsening? The stakes are very high, including the lives of millions of human beings and hundreds of billions of dollars.

Many cite the 1980s as the turning point toward American fatness. What happened then? After about 1976, "everyone" says, body movement declined, with couch potatoes taking more TV time. After the 1990s, everyone started sitting more to use computers and surf the Internet. McDonald's and all of its competitors began to burgeon in the 1960s, competing on cheapest price, largest size portions, and best taste (just the right mix of added salt and sugar).

The two-income family became the norm, with both fast and processed foods (usually added sugar) becoming usual—not exceptional—fare to save food preparation time and money. Sugared breakfast cereal became the norm for American kids. Sugar-loaded fruit juices were pushed as healthy and necessary every morning, joining the ubiquitous sugared sodas. The average American would come to lead the world by consuming more than 120 g of sugar daily, or more than100 lb per year.[2]

Mandatory physical education disappeared from schools. Oral antibiotics for just about every little human indication changed the gut microbiome greatly; plus, of course, there was massive use of antibiotics in livestock. Childhood infectious diseases became unusual. The gene pool did not change, but we now know that epigenetic elements can be altered by experience and transmitted.

In addition to all that gemisch, various groups look at this conundrum in greatly disparate ways. One holds that obesity and diabetes are so intertwined that, since insulin is obviously tied to diabetes and since insulin is a hormone, they must together be an endocrinologic disorder. But if that is true, why haven't the endocrinologists figured it out? Could it be because they have been so busy reaping the financial rewards of caring for a bonanza of diabetic patients as well as chasing incidental thyroid nodules? Or does Big Pharma love profiting from the many expensive new diabetes drugs—and crave new obesity drugs?

A statement from the Endocrine Society[3] states, "...Growing evidence suggests that obesity is a disorder of the energy homeostasis system, rather than simply arising from the passive accumulation of excess weight..." The argument proposing that sugar is the main culprit is strongly put forward by Gary Taubes in his 2016 book, The Case Against Sugar.[4]

The notion that obesity is primarily caused by the ability of carbohydrates to increase insulin secretion, which reduces levels of circulating fuels (glucose and free fatty acids); shunts fat into fat cells; and makes us fat, hungry, and sluggish, is buttressed by a 2018 article in JAMA by Ludwig and Ebbeling[5] that lays out their argument for the carbohydrate-insulin model, or CIM, as they refer to it. Guyenet argues that the puzzle is far more complicated than any of these proposals.[6,7]

The long-time conventional view is that the laws of thermodynamics have not been broken by biology. One calorie is one calorie; calories out must equal or be greater than calories in or we gain weight. Of course, since academics, professional organizations, public health bodies, government agencies, much of corporate America, journalists, marketing, and advertising have pushed the "calories are calories" idea as dogma for many decades, it won't be replaced any time soon.

There is still much to talk about...another time. That's my opinion. I'm Dr George Lundberg, at large at Medscape


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