Bad reporting on a bad study

Post #411,566 by drook 7/6/16 11:02:19 AM 7/6/16 11:02:19 AM Reply	Bad reporting on a bad study 1) Where's the link to the study so we can see what it actually said? 2) They keep listing saturated fat in the same phrases with trans fat, as though they're the same. 3) Observational studies with questionnaires spaced 2-4 years apart are at best useful for creating a hypothesis, not for proving one. There's much more, but that's off the top of my head. -- Drew
Post #411,568 by Another Scott 7/6/16 11:16:30 AM 7/6/16 11:16:30 AM Reply	Re: Bad reporting on a bad study Agreed, reports like this should always cite the original paper. http://archinte.jamanetwork.com/article.aspx?articleid=2530902 is the JAMA Internal Medicine article. Signing up for a free account doesn't give one access to it - on has to buy it. :-( Objective To examine the associations of specific dietary fats with total and cause-specific mortality in 2 large ongoing cohort studies. Design, Setting, and Participants This cohort study investigated 83 349 women from the Nurses’ Health Study (July 1, 1980, to June 30, 2012) and 42 884 men from the Health Professionals Follow-up Study (February 1, 1986, to January 31, 2012) who were free of cardiovascular disease, cancer, and types 1 and 2 diabetes at baseline. Dietary fat intake was assessed at baseline and updated every 2 to 4 years. Information on mortality was obtained from systematic searches of the vital records of states and the National Death Index, supplemented by reports from family members or postal authorities. Data were analyzed from September 18, 2014, to March 27, 2016. Main Outcomes and Measures Total and cause-specific mortality. Results During 3 439 954 person-years of follow-up, 33 304 deaths were documented. After adjustment for known and suspected risk factors, dietary total fat compared with total carbohydrates was inversely associated with total mortality (hazard ratio [HR] comparing extreme quintiles, 0.84; 95% CI, 0.81-0.88; P Conclusions and Relevance Different types of dietary fats have divergent associations with total and cause-specific mortality. These findings support current dietary recommendations to replace saturated fat and trans-fat with unsaturated fats. Health Professionals Follow-up Study FAQ: Q. What kinds of questions are on the questionnaires? A. The questionnaires include items about medical conditions, medications, tobacco use, and exercise. In addition, every four years a food frequency questionnaire is administered to collect detailed information about amounts and types of foods and beverages consumed. Q. How do you know that the questionnaires are eliciting accurate information? A. The validity of self-reported information has been tested several times by comparing subject reports against actual measurements. The evidence indicates that the data gathered in the Health Professionals Follow-Up Study has a high degree of validity. (See publication lists for studies of questionnaire validity.) FWIW. Cheers, Scott.
Post #411,571 by drook 7/6/16 11:51:34 AM 7/6/16 11:51:34 AM Reply	Not helping "recommendations to replace saturated fat and trans-fat with unsaturated fats." I just spent 10 minutes searching and can't find the actual survey questions. But from questionnaires I have seen, they typically conflate fats into groups based on the current understanding of what matters. So all saturated fats - including animal fats and trans fats - were grouped together for years. Makes long-term comparisons problematic. -- Drew
Post #411,572 by Another Scott 7/6/16 12:34:25 PM 7/6/16 12:34:25 PM Reply	The studies look at people over a long period of time. Transfats weren't commonly recognized as a problem until, what, 2006? Both of the studies looked at periods ending in 2012: This cohort study investigated 83 349 women from the Nurses’ Health Study (July 1, 1980, to June 30, 2012) and 42 884 men from the Health Professionals Follow-up Study (February 1, 1986, to January 31, 2012) The questionaires for the latter study are here. Click on the "Diet" tab in the table. The questions seem reasonable, but of course, they're not comprehensive, and people have to estimate (unless they're keeping a journal (and I think I read somewhere that many people do). I think everyone agrees that it's not ideal, but it's a lot of data and they've tried to make the data as broadly useful as possible. The problems with trying to document everything about a diet, and try to have enough people eat a particular diet to test various hypotheses are obvious. Presumably they have enough data to separate out trans-fats from saturated fats, at least in some cases. I would be surprised if those results were different from the general consensus now. FWIW. :-) Cheers, Scott.
Post #411,573 by drook 7/6/16 12:58:10 PM 7/6/16 12:58:10 PM Reply	Re: The studies look at people over a long period of time. See the first line on that tab: Semi-quantitative food frequency questionnaire (diet in past year) That's referring to the questionnaire with the questions I want to see. And I want to see how those questions have changed over the decades. They can't draw any supposed conclusions about the effect of different types of fats if they haven't even been separating the different types of fats in their questions. Compounded by the fact that even once researchers started to understand that there were differences, the people they were asking either didn't understand or had no way to identify what they were actually eating. -- Drew
Post #411,574 by Another Scott 7/6/16 1:21:31 PM 7/6/16 1:21:31 PM Reply	See the 2006 Long form. https://www.hsph.harvard.edu/hpfs/pdfs/06L.pdf That seems to be the extent of the diet questions that they ask every 2 years. I assume you can see the changes by looking at the Long forms going back in 2 year increments. It would be blind guesswork if people were changing their diets all the time, going out to dinner all the time, etc., but I think that they have published evidence that that isn't what's going on (and most participants seem to keep track anyway). HTH. Cheers, Scott.
Post #411,575 by drook 7/6/16 2:40:11 PM 7/6/16 2:40:11 PM Reply	As bad as I thought Let's assume I'm trying as hard as I can to be honest and thorough. I keep track of absolutely everything I eat. I want to fill this out accurately. I've just eaten a Lean-Cuisine Creamy Basil Chicken with Tortellini. The ingredients are: skim milk, low fat asiago cheese tortellini (enriched extra fancy durum flour and semolina [durum wheat flour, semolina, niacin, iron {ferrous sulfate}, thiamin mononitrate, riboflavin, folic acid], water, fat free ricotta cheese [pasteurized whey, pasteurized skim milk, vinegar, xanthan gum, vitamin a palmitate], whole eggs, asiago cheese [pasteurized milk, cheese cultures, salt, enzymes], bread crumbs [wheat flour], skim milk with vitamin a added, parmesan cheese [pasteurized part skim milk, cheese cultures, salt, enzymes], romano cheese made from cow's milk [pasteurized milk, cheese cultures, salt, enzymes], cooked onions, low moisture part skim mozzarella cheese [pasteurized milk, cheese cultures, salt, enzymes], butter [cream, salt], brown sugar [sugar, cane syrups], white distilled vinegar [white distilled vinegar, water], roasted garlic, cooked garlic, spices, salt, modified cornstarch, beta carotene), cooked white meat chicken (white meat chicken, water, modified tapioca starch, chicken flavor [dried chicken broth, chicken powder, natural flavor], carrageenan, whey protein concentrate, soybean oil, corn syrup solids, sodium phosphate, salt), italian green beans, water, yellow carrots, red peppers, 2% or less of cream, modified cornstarch, parmesan cheese paste (granular and parmesan cheese [pasteurized milk, cheese cultures, salt, enzymes], water, salt, lactic acid, citric acid), basil, garlic puree, potato starch, sea salt, butter (cream, salt), dried cream extract, yeast extract, potassium chloride, spice, xanthan gum, lactic acid, calcium lactate, seasoning (wheat starch, extracts of annatto and turmeric color, natural flavor). How do I fill out the survey for that? Back in the 50s you could probably ask a housewife what their family ate that week and she could figure it out with a little work. Today? Good luck. Which, by the way, would actually be a great survey: How often do you cook from scratch vs. prepared heat-and-eat foods, and how does that correlate with health? -- Drew
Post #411,578 by Another Scott 7/6/16 3:37:25 PM 7/6/16 3:37:25 PM Reply	Yup, prepared foods and eating out are big wild-cards.
Post #411,576 by a6l6e6x 7/6/16 3:13:37 PM 7/6/16 3:13:37 PM Reply	LRPD: Powered by scientifically unsubstantiated energy producing capabilities! Alex "There is a cult of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that "my ignorance is just as good as your knowledge." -- Isaac Asimov
Post #411,577 by malraux 7/6/16 3:34:25 PM 7/6/16 3:34:25 PM Reply	And if someone can find a cure for it a lot of the other problems will diminish. Regards, -scott Welcome to Rivendell, Mr. Anderson.
Post #411,579 by drook 7/6/16 4:09:34 PM 7/6/16 4:09:34 PM Reply	I keep looking for the phrase, "According to top Chinese and Russian scientists..." -- Drew

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