Wikipedia:Reference desk/Archives/Science/2019 June 13

= June 13 =

Glasses Prescription
(This may seem to skirt on a "medical advice" question, but I am really interested more in the political aspect) I have worn prescription glasses for nearly 40 years. Every optometrist/optician I have ever visited (and there have been many), had this rule that they will not fill a prescription older than two years. But one day I broke my last pair, and an optician I was friendly with agreed to fill the prescription, even though it was three years old. He just shrugged, and said it was not a law, just more of an industry standard that was abided by to ensure continued business. Is that true, or is it actually regulated by some authority? If the former, it kind of seems like a type of collusion to me. Ditch &#8733; 00:08, 13 June 2019 (UTC)


 * In the U.S., the expiration date for eyeglass prescriptions are set by state law (as opposed to drugs, which is set by federal law). See - Nunh-huh 01:35, 13 June 2019 (UTC)
 * So it is regulated. That is extremely helpful, and answers my question, thank you!  Ditch &#8733;  02:13, 13 June 2019 (UTC)


 * You're welcome. It's regulated by some states; some other states just don't address it.- Nunh-huh 02:39, 13 June 2019 (UTC)


 * According to the FDA, spectacle lenses and frames are regulated as medical devices and are subject to certain federal regulations.
 * In fact, even non-prescription sunglasses are subject to regulation as a medical device, as described in this FDA publication Guidance Document For Nonprescription Sunglasses. One might opine that the degree of regulation, and the priority of enforcement, is commensurate to the administration's tendency toward non-interference when there is no real harm to a consumer; but the law still says that the products and the way that companies advertise and commercialize them must be in compliance with specified Federal regulations.  For example, claims of protection from ultraviolet light have historically been scrutinized for scientific accuracy.  See also, Is The Product a Medical Device?  The textbook examples, often studied by law students, are the tongue depressor and the popsicle stick: outwardly, these are the same physical object, but when commercially marketed for medical use, the item becomes subject to 21 C.F.R. 880.6230.
 * This might seem heavy-handed to some observers - how and why would the Feds interfere with a simple eyeglass purchase? Everything in these rules becomes context-relative: if somebody commercially sells a plastic lens and tells you that it has corrective power to aid your eyesight, they need to be able to legally demonstrate that they have authority to make that claim (e.g. because they are appropriately licensed) and that the device functions as they claim (e.g. that they aren't selling fraudulent or harmful material). Money is being exchanged, it's interstate commerce even if the cats never leave the house, "...and here's why...", etc., etc., and therefore it also falls under Federal jurisdiction, unless they delegate those regulatory powers to local or state government.
 * Most of the time, FDA is too busy to care if somebody is selling counterfeit popsicle sticks, or operating an out-of-licensure expired-eyeglasses-prescription bootleg operation. However: if somebody does these things it somehow causes harm, rest assured that when the proverbial book is thrown, it lands with a heavy blow.  And if you think expired eyeglasses are bad, just wait until you read about the lengthy prison sentences for mislabeling expired crabs.  Statutory crab-expiry carries a greater Federal prison sentence than practical insurrection against the United States, which is bafflingly a Constitutionally-protected right.
 * Nimur (talk) 02:45, 13 June 2019 (UTC)
 * The Malheur occupation was maybe not the most representative example of "insurrection"; the charges were conspiracy to obstruct federal employees, firearms violations, theft, and damaging the refuge. No one was charged with insurrection, which is a crime under U.S. Code Title 18, Chapter 115. Some were convicted of the latter offenses. --47.146.63.87 (talk) 01:30, 14 June 2019 (UTC)
 * Also, no offense intended, but while that's informative about issues surrounding federal regulation, it isn't really relevant to the question. Federal law, I believe, only sets expiration times for prescriptions for controlled substances, which eyeglasses are not. Otherwise, expiration is up to state law, as Nunh-huh noted. (I don't know how this works for territories or D.C. Would be interested if anyone knows!) Anyone wanting to learn more about U.S. medical device regulation may be interested in and medical device design (which appears to only address the U.S. and needs editorial work). --47.146.63.87 (talk) 01:44, 14 June 2019 (UTC)
 * I apologize, I went a little overboard with my response. My point can be summarized: eyeglasses are subject to Federal laws that regulate medical devices; but the legal consequences of these rules are rarely visible to an end-consumer.  Nimur (talk) 15:14, 14 June 2019 (UTC)
 * One issue is that you may require prescription lenses to drive safely, and if the prescription is old then this increases the chance that your eyes have changed and you now need a different prescription. --76.69.46.228 (talk) 03:37, 13 June 2019 (UTC)
 * But your ability to drive safely is the driver's legal responsibility, not the optometrist's. They may have a responsibility to warn (or even report) drivers with inadequate sight, after a test. But it would be far rarer for them to be required to pre-emptively screen everyone, on the grounds that the might be losing their sight. Andy Dingley (talk) 10:20, 13 June 2019 (UTC)
 * I'm just saying that this sort of consideration might be what the people who made regulations such as we were asked about had in mind. --76.69.46.228 (talk) 18:43, 14 June 2019 (UTC)
 * besides, a hell of a lot of people drive with more than 2 years old eyeglass. Gem fr (talk) 15:06, 13 June 2019 (UTC)
 * But that's a risk taken by the patient, not the optician or whomever. If someone drove with old glasses, hadn't had an exam in years, and got in a crash, if they sued their optician, the suit would likely be quickly dismissed after showing the patient hadn't had an exam lately and had been given the standard advice to have regular exams. --47.146.63.87 (talk) 01:30, 14 June 2019 (UTC)
 * Your argument might eventually win in court, but, especially in the U.S., medical professionals often practice defensive medicine to reduce the risk of being sued. Defending against a lawsuit is expensive, and, if you're required to carry malpractice insurance, will likely cause its premiums to rise substantially, as the insurer usually bears the cost of defending you against a malpractice suit. Refusing to fill old prescriptions costs you nothing other than potentially disgruntling some customers, and might even make money if you're part of a practice, as now the patient might get a new exam for a prescription. --47.146.63.87 (talk) 01:30, 14 June 2019 (UTC)


 * Local rules vary, but it's mostly a liability issue, rather than prescriptions. If you have a condition like glaucoma, that is usefully detectable by regular screening (in my country, the usual nominal fee for testing is waived if there's a family history). If you then went on to develop it, after visiting an optician but not having been screened for it, then that could be seen as a liability on their part. Andy Dingley (talk) 10:20, 13 June 2019 (UTC)
 * Agreed, see this from the UK National Health Service which has no profit motive except to save British tax payers' money:
 * "Glaucoma is usually picked up during a routine eye test, often before it causes any noticeable symptoms... It's important to have regular eye tests so problems such as glaucoma can be diagnosed and treated as early as possible. Early treatment can help stop your vision becoming severely affected. You should have an eye test at least every 2 years. National Health Service - Glaucoma - Diagnosis. Alansplodge (talk) 21:40, 13 June 2019 (UTC)
 * Yes, that's another factor: to kind of "force" people to get regular exams—although some might consider this slightly underhanded. Eye exams can often detect early signs of various diseases, such as diabetes. --47.146.63.87 (talk) 01:30, 14 June 2019 (UTC)
 * A boy went into a High Street opticians and underwent an eye examination.  He had a condition where pressure builds up at the back of the eye.   It is easily detected and easily treated.   If not treated it proves fatal.      The optometrist did not pick up the condition and the boy died.   She was convicted of manslaughter. 2A02:C7F:A42:AD00:6D9E:CD5D:662E:5310 (talk) 17:47, 14 June 2019 (UTC)
 * Although she was cleared on appeal. Andy Dingley (talk) 20:19, 14 June 2019 (UTC)

Gaining weight / losing weight
Generally speaking, gaining weight is accomplished by three things: (A) eating more food / calories (i.e., increasing calories consumed); (B) exercising / working out less (i.e., decreasing calories expended);  or (C) some change in metabolism. Naturally, losing weight is the opposite. So, what exactly is the case when the side effect of a pill is listed as "weight gain" (or, conversely, "weight loss")? (A) The pill does not put food in your mouth or remove food from your mouth. Maybe it makes you more/less hungry? (B) The pill does not make you work out or prevent you from working out. Maybe it makes you more/less tired or more/less energetic? (C) Perhaps the pill has some effect on your metabolism? So, generally speaking, what does the pill do to your body that has the effect of you gaining/losing weight? Thanks. Joseph A. Spadaro (talk) 20:27, 13 June 2019 (UTC)
 * It would depend on the pill you're asking about. Perhaps a classic is thyroxine, which works to replace the hormone produced by an underactive thyroid gland. The thyroid produces thyroid hormone which regulates the metabolism. If it is underactive, the metabolism drops, potentially leading to weight gain. Taking the hormone to normal levels with an artificial replacement stops this and the weight might return to normal.--Phil Holmes (talk) 20:48, 13 June 2019 (UTC)


 * Thanks. But, that's not really what I had in mind.  The thyroid, metabolism, and weight gain/loss are all closely interconnected and interrelated.  If you are lacking thyroid hormone (due to an under-active thyroid), then the thyroxine pill simply brings you back to a "normal level".  Hence, your thyroid becomes normal; your metabolism becomes normal; your weight becomes normal.  My original question was referring to a pill totally unrelated to a direct cause of weight loss/gain.  For example: "This pill for schizophrenia (or depression) has the side effect of weight gain/loss."  Thanks.    Joseph A. Spadaro (talk) 00:28, 14 June 2019 (UTC)
 * One of the issue with medication is that they have Side effect. Gem fr (talk) 03:02, 14 June 2019 (UTC)
 * A fundamental, relevant concept is that putting food in your mouth -> gut does not put nutrition in your tissues/organs. The gut is a tube that passes through us; only if the nutrients are absorbed will they provide nutrition - and various factors increase/decrease absorption of nutrients. Many foods need processing (physical and/or chemical change) in the gut before they can be absorbed. &mdash; soupvector (talk) 05:06, 14 June 2019 (UTC)
 * indeed. And many medication have a side effect on the working of the gut and its microbiota. Human_microbiota has a nice illustration of it. Gem fr (talk) 05:43, 14 June 2019 (UTC)
 * Some medications can affect appetite. Antipsychotics, I believe, can increase appetite. Many stimulant drugs decrease appetite, and are sometimes prescribed for this purpose. Note as well that manufacturers, agencies, etc. tend to err on the side of caution when listing possible side effects of medication. If trials of a drug showed a difference in something against the control group, this will get listed as a possible side effect, though it could be caused by something other than the drug, or just a fluke. Many illnesses can lead to weight changes, and determining whether something is caused by an illness or a treatment for that illness is tricky and requires studies specifically aimed at doing so, but those studies typically aren't part of the approval process for a drug. --47.146.63.87 (talk) 07:01, 14 June 2019 (UTC)


 * Another possible iatrogenic cause of weight gain is water-retention, such as with oral steroids: . SinisterLefty (talk) 03:11, 16 June 2019 (UTC)

Thanks, all. Joseph A. Spadaro (talk) 14:30, 15 June 2019 (UTC)

Voice detection
Can you detect a gay man by his voice and intonation?80.2.22.19 (talk) 22:51, 13 June 2019 (UTC)
 * Me, no I don't think I can but the article Gaydar notes acoustic analyses that found differences in how gay and straight men pronounce "s" sounds. DroneB (talk) 23:22, 13 June 2019 (UTC)
 * For additional stereotypes, see LGBT stereotypes. ←Baseball Bugs What's up, Doc? carrots→ 23:38, 13 June 2019 (UTC)


 * Being gay (or not) won't prevent him to be detected by his voice, for sure. ;-) Gem fr (talk) 02:57, 14 June 2019 (UTC)


 * Media pushes a stereotypical voice for gay men. Some gay men recreate that stereotypical voice because media tells them that is how they should sound. Then, media uses those examples to justify their use of the stereotypical voice. In a feedback loop, it becomes more and more pronounced. So, some men, purposely or through years of influence, have a stereotypical "gay voice." Many do not. Some men who are not gay, also adopt the voice for whatever reason. This is not a "gay thing." It is just how media and society work. If you are black, you know that you aren't supposed to like anything with mayonnaise in it because media tells you that black people don't like mayonnaise. You don't want to be weird, so you accept it. If you are white, you know that you can't dance because media tells you that you can't dance. So, don't even try. There are many stereotypical feedback loops between media and society. Social media is making it far worse. 68.115.219.130 (talk) 11:24, 14 June 2019 (UTC)
 * Black people don't like mayonnaise? And I should just give up dancing because I'll never be any good at it? Gosh the things I learn from Wikipedia! ;-) Dmcq (talk) 13:37, 14 June 2019 (UTC)
 * for what this is worth, La Cage aux Folles (musical) feature a gay couple, one being the stereotypical drag queen, the other a man you wouldn't tell (even quite macho in the way he treats his spouse). Of course this is entertainment, not real, but the rationale is solid: gay men can mimic women, or just be the other guy. They say some do both, night and day. Gem fr (talk) 17:07, 14 June 2019 (UTC)