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View Diary: A Trans Fat Ban and Marijuana Legalization: Liberal Hypocrisy? (139 comments)

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  •  Your link is mostly dis-information. (0+ / 0-)
    •  Let's got straight to the literature then. (6+ / 0-)

      Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease


      Background: A reduction in dietary saturated fat has generally been thought to improve cardiovascular health.

      Objective: The objective of this meta-analysis was to summarize the evidence related to the association of dietary saturated fat with risk of coronary heart disease (CHD), stroke, and cardiovascular disease (CVD; CHD inclusive of stroke) in prospective epidemiologic studies.

      Design: Twenty-one studies identified by searching MEDLINE and EMBASE databases and secondary referencing qualified for inclusion in this study. A random-effects model was used to derive composite relative risk estimates for CHD, stroke, and CVD.

      Results: During 5–23 y of follow-up of 347,747 subjects, 11,006 developed CHD or stroke. Intake of saturated fat was not associated with an increased risk of CHD, stroke, or CVD. The pooled relative risk estimates that compared extreme quantiles of saturated fat intake were 1.07 (95% CI: 0.96, 1.19; P = 0.22) for CHD, 0.81 (95% CI: 0.62, 1.05; P = 0.11) for stroke, and 1.00 (95% CI: 0.89, 1.11; P = 0.95) for CVD. Consideration of age, sex, and study quality did not change the results.

      Conclusions: A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD. More data are needed to elucidate whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat.

    •  A systematic review of the evidence (4+ / 0-)
      Recommended by:
      badger, kyril, semiot, Tonedevil

      A systematic review of the evidence supporting a causal link between dietary factors and coronary heart disease.


      Although a wealth of literature links dietary factors and coronary heart disease (CHD), the strength of the evidence supporting valid associations has not been evaluated systematically in a single investigation.

      We conducted a systematic search of MEDLINE for prospective cohort studies or randomized trials investigating dietary exposures in relation to CHD. We used the Bradford Hill guidelines to derive a causation score based on 4 criteria (strength, consistency, temporality, and coherence) for each dietary exposure in cohort studies and examined for consistency with the findings of randomized trials.

      Strong evidence supports valid associations (4 criteria satisfied) of protective factors, including intake of vegetables, nuts, and "Mediterranean" and high-quality dietary patterns with CHD, and associations of harmful factors, including intake of trans-fatty acids and foods with a high glycemic index or load. Among studies of higher methodologic quality, there was also strong evidence for monounsaturated fatty acids and "prudent" and "western" dietary patterns. Moderate evidence (3 criteria) of associations exists for intake of fish, marine omega-3 fatty acids, folate, whole grains, dietary vitamins E and C, beta carotene, alcohol, fruit, and fiber. Insufficient evidence (< or =2 criteria) of association is present for intake of supplementary vitamin E and ascorbic acid (vitamin C); saturated and polyunsaturated fatty acids; total fat; alpha-linolenic acid; meat; eggs; and milk. Among the dietary exposures with strong evidence of causation from cohort studies, only a Mediterranean dietary pattern is related to CHD in randomized trials.

      The evidence supports a valid association of a limited number of dietary factors and dietary patterns with CHD. Future evaluation of dietary patterns, including their nutrient and food components, in cohort studies and randomized trials is recommended.

      •  While I commend you for linking a metastudy... (0+ / 0-)

        rather than just a single independent study, or worse an article summarizing one, it must be pointed out that there have been a vast number of studies on this, and even a single metastudy doesn't bear that much weight on its own. Some metastudies from the past couple decades concerning the relationship between saturated fat and cardiovascular disease:

        Hooper, 2011:     Reducing saturated fat in diets reduced the risk of having a cardiovascular event by 14 percent (no reduction in mortality).
        Mozaffarian, 2010: 19% reduction in Coronary Heart Disease (CHD) events by replacing saturated fatty acids (SFA) with polyunsaturated fatty acids (PUFA). (Note: the study included n-3 fatty acids in the PUFA group).
        Siri-Tarino, 2010: No significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD.
        Danaei, 2009: Intervention studies replacing SFA with PUFA showed an insignificant relative risk (1.01-1.04) for IHD.
        Mente, 2009: Insignificant
        Skeaff, 2009: Reduced events by substituting PUFA
        Jakobsen, 2009: 5% SFA replaced with PUFA: 13% decrease in events, 26% decrease in deaths
        Van Horn, 2008: 25-35% fats but <7% SFA and TFA reduces risk.
        Chanu, 2003: Significant in longer term.
        Hu, 1999:    Eating nuts in place of SFA gave 45% reduction.
        Truswell, 1994: Decrease SFA and cholesterol intake, partial replacement with PUFA: 6% reduced deaths, 13% reduced events

        You linked only Mente. Why? Because it said what you wanted to see? It's clear that the overwhelming majority of metastudies show a link. Furthermore, the link is supported by the World Health Organization, the American Dietetic Association, the Dietitians of Canada, the British Dietetic Association, the American Heart Association, the British Heart Foundation, the World Heart Federation, the British National Health Service, the United States Food and Drug Administration, and the European Food Safety Authority, among many others.

        Já þýðir já. Nei þýðir nei. Hvað er svona erfitt við það?

        by Rei on Wed Jan 29, 2014 at 04:51:31 AM PST

        [ Parent ]

        •  Look closer, I linked to three (0+ / 0-)

          different meta-studies.

          Looking through your list (thanks btw, super useful) it's clear that there is a lot of noise and little signal. My point is that the evidence was pretty thin for such a confident admonishment.

          If we look at a literature review that looks specifically at a type of animal fat rather than replacing SFA with PUFAs, we find evidence that whole fat dairy is correlated with better health outcomes than low fat dairy.

          The relationship between high-fat dairy consumption and obesity, cardiovascular, and metabolic disease

          To comprehensively review the data on the relationship between the consumption of dairy fat and high-fat dairy foods, obesity, and cardiometabolic disease.

          We have conducted a systematic literature review of observational studies on the relationship between dairy fat and high-fat dairy foods, obesity, and cardiometabolic disease. We have integrated these findings with data from controlled studies showing effects of several minor dairy fatty acids on adiposity and cardiometabolic risk factors, and data on how bovine feeding practices influence the composition of dairy fat.

          In 11 of 16 studies, high-fat dairy intake was inversely associated with measures of adiposity. Studies examining the relationship between high-fat dairy consumption and metabolic health reported either an inverse or no association. Studies investigating the connection between high-fat dairy intake and diabetes or cardiovascular disease incidence were inconsistent. We discuss factors that may have contributed to the variability between studies, including differences in (1) the potential for residual confounding; (2) the types of high-fat dairy foods consumed; and (3) bovine feeding practices (pasture- vs. grain-based) known to influence the composition of dairy fat.

          The observational evidence does not support the hypothesis that dairy fat or high-fat dairy foods contribute to obesity or cardiometabolic risk, and suggests that high-fat dairy consumption within typical dietary patterns is inversely associated with obesity risk. Although not conclusive, these findings may provide a rationale for future research into the bioactive properties of dairy fat and the impact of bovine feeding practices on the health effects of dairy fat.

          The advice to choose low fat dairy serves as virtual punctuation in nutrition discussions, and yet it's unsupported by the evidence.

          Again, thanks for the list of studies, this a topic I intend to do a deep dive into in a future diary or series of diaries.

          •  I think there's quite a lot of signal (0+ / 0-)

            The metastudies are quite clearly on the side of a link, with only a few exceptions.

            Or, let's be more concise: do you think that all of the world's major health associations are run by idiots who don't know the current medical literature?

            Já þýðir já. Nei þýðir nei. Hvað er svona erfitt við það?

            by Rei on Wed Jan 29, 2014 at 09:11:41 AM PST

            [ Parent ]

            •  I think on this question (0+ / 0-)

              Ancel Keys successfully and erroneously set the debate and a lot of confirmation bias and inertia has carried the issue since then.  

              I don't take a position in contradiction of a scientific consensus lightly. I think the debate has been shifting from consensus to contested because it was never on as firm a footing as was originally believed.

    •  The questionable role of saturated fat . . . (4+ / 0-)
      Recommended by:
      badger, kyril, semiot, Tonedevil

      The questionable role of saturated and polyunsaturated fatty acids in cardiovascular disease.


      A fat diet, rich in saturated fatty acids (SFA) and low in polyunsaturated fatty acids (PUFA), is said to be an important cause of atherosclerosis and cardiovascular diseases (CVD).

      The evidence for this hypothesis was sought by reviewing studies of the direct link between dietary fats and atherosclerotic vascular disease in human beings. The review included ecological, dynamic population, cross-sectional, cohort, and case-control studies, as well as controlled, randomized trials of the effect of fat reduction alone. The positive ecological correlations between national intakes of total fat (TF) and SFA and cardiovascular mortality found in earlier studies were absent or negative in the larger, more recent studies.

      Secular trends of national fat consumption and mortality from coronary heart disease (CHD) in 18-35 countries (four studies) during different time periods diverged from each other as often as they coincided. In cross-sectional studies of CHD and atherosclerosis, one group of studies (Bantu people vs. Caucasians) were supportive; six groups of studies (West Indians vs. Americans, Japanese, and Japanese migrants vs. Americans, Yemenite Jews vs. Yemenite migrants; Seminole and Pima Indians vs. Americans, Seven Countries) gave partly supportive, partly contradictive results; in seven groups of studies (Navajo Indians vs. Americans; pure vegetarians vs. lacto-ovo-vegetarians and non-vegetarians, Masai people vs. Americans, Asiatic Indians vs. non-Indians, north vs. south Indians, Indian migrants vs. British residents, Geographic Study of Atherosclerosis) the findings were contradictory.

      Among 21 cohort studies of CHD including 28 cohorts, CHD patients had eaten significantly more SFA in three cohorts and significantly less in one cohort than had CHD-free individuals; in 22 cohorts no significant difference was noted. In three cohorts, CHD patients had eaten significantly more PUFA, in 24 cohorts no significant difference was noted. In three of four cohort studies of atherosclerosis, the vascular changes were unassociated with SFA or PUFA; in one study they were inversely related to TF. No significant differences in fat intake were noted in six case-control studies of CVD patients and CVD-free controls; and neither total or CHD mortality were lowered in a meta-analysis of nine controlled, randomized dietary trials with substantial reductions of dietary fats, in six trials combined with addition of PUFA.

      The harmful effect of dietary SFA and the protective effect of dietary PUFA on atherosclerosis and CVD are questioned.

    •  If you've got (5+ / 0-)
      Recommended by:
      badger, kyril, murrayewv, semiot, Tonedevil

      literature reviews or meta-analysis that supports your position, feel free to share. I'm always looking to falsify my beliefs if they don't reflect the weight of the evidence.

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