How artificial sweeteners cause obesity

I had heard that using artificial sweeteners can cause obesity, but hadn't before seen an explanation. This article by Tom Philpott of Mother Jones describes the mechanism:

[A] slew of studies have shown that faux sugars may actually contribute to the very diet-related maladies they're marketed to protect us from—type 2 diabetes, hypertension, metabolic syndrome, strokes, and heart attacks... [T]hose who drank at least one diet soda per day were 43 percent more likely to suffer strokes and heart attacks than people who drank none, even after controlling for such factors as weight, level of exercise, diabetes, high blood pressure, and intake of calories, cholesterol, and sodium. Another large population study, published in 2009, found that daily diet soda drinkers were 67 percent more likely to develop type 2 diabetes than people who shun them—again, even after adjusting for lifestyle and demographic factors. ... Purdue University behavioral neuroscientist Susan Swithers suggests that fake sweeteners do their dirty work by confusing our digestive systems' Pavlovian response to sugar. When you smell food, she explains, you begin to salivate and your stomach begins to grumble; that's your body preparing for what it assumes from experience is a hearty meal to come. Similarly, she says, a sweet taste is a "pretty good indication that sugar is going to arrive in your body"—that is, a blast of easily digestible calories. So, quaff Pepsi, and your body starts releasing digestive hormones and increases its metabolic rate, "because you have to expend energy to get energy out of your food," she explains. Fake sweeteners appear to subtly disrupt the trillions of microbes that live in our digestive tracts. But when you start ingesting sweet blasts that then don't deliver the usual calorie blast, your body no longer knows what to expect. As a result, Swithers says, tests have found that "animals who have experience with artificial sweeteners don't seem to be as good at regulating their blood sugar levels when they get real sugar"—hence the associations with diabetes and other metabolic troubles. And this mechanism would appear to be independent of the kind of low-calorie sweetener used.

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Gluten Sensitivity as a Nocebo

There's an awfully large amount of money being spent on special gluten free products.  How many of the people who buy these products really need them?   According to this article on Buzzfeed, not many.    The most memorable passages from this article:

17 million people may unnecessarily believe that they are gluten-sensitive. (Source: A Mayo Clinic survey in 2012, cited in a NY Times article.)

[We] spent $10.5 billion last year on gluten-free products. (Source: Mintel, a market research company, cited in the NY Times article.)

It is especially important because a psychological disease can spread as fast as any virus but be more enduring.

A 2012 Mayo Clinic survey concluded that only 1.8 million Americans have Celiac disease. Only 1.8 million people should be on a non-gluten diet. Compare this to the 18 million people who consider themselves “gluten sensitive”

According to this article many of the people who spend lots of money on gluten-free products, gluten serves as a "nocebo," defined below by Wikipedia:
a nocebo (Latin for "I shall harm") is a harmless substance that creates harmful effects in a patient who takes it. The nocebo effect is the negative reaction experienced by a patient who receives a nocebo. Conversely, a placebo is an inert substance that creates either a positive response or no response in a patient who takes it. The phenomenon in which a placebo creates a positive response in the patient to which it is administered is called the placebo effect. The nocebo effect is less well-studied and well-known, by both scientists and the public, than the placebo effect.
What's the evidence that gluten is not detrimental to most people who are committed to gluten free products?
This disease is largely self-diagnosed, and studies are starting to show that it may be real in a great number of cases. Professor and scientist Peter Gibson is no stranger when it comes to studying gluten. He did a study in 2011 that gave a lot of credit to the belief in (non-Celiac) gluten sensitivity. Seeing that NCGS had become a worldwide phenomenon, he revisited the topic in 2013 with a critical look at the original assumptions. These are the measures he took to validate his results: Subjects were given every single meal for the duration of the study.Any other potential causes of bad stomach symptoms were removed from the diet. (Think lactose from milk.) Just in case you do not think he was serious, Peter collected nine days worth of urine and fecal matter. (Now that’s a topic of conversation.) The results were pretty shocking. They concluded that gluten in no way could have caused any of the negative symptoms that the subjects were suffering from.  
Most claims of the need to be gluten free are starting to remind me of the phenomenon of facilitated communication regarding autistics.

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Neil deGrasse Tyson comment on GMOs blows up into a detailed discussion

Neil DeGrasse Tyson has been criticized by the anti-GMO crowd for not condemning GMOs during an interview during a book signing. He has now expanded his comments, as reported by Raw Story:

If your objection to GMOs is the morality of selling non-perennial seed stocks, then focus on that. If your objection to GMOs is the monopolistic conduct of agribusiness, then focus on that. But to paint the entire concept of GMO with these particular issues is to blind yourself to the underlying truth of what humans have been doing — and will continue to do — to nature so that it best serves our survival,” he advised. “That’s what all organisms do when they can, or would do, if they could. Those that didn’t, have gone extinct extinct.

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