REattempt
Recycles dryer sheets
- Joined
- Feb 27, 2010
- Messages
- 293
I never said long-term. I don't think we actually need long term to demonstrate the benefits. Ornish did perform a peer reviewed RCT to demonstrate reversal of CHD, without drugs or surgery, using a low-fat (<10%), plant based diet...without calorie restrictions.Note that a long-term randomized controlled experiment has never been done and is not feasible. That is, you can't take a group of 40-year-olds, and randomly assign them to a diet, and then follow them for 20 years. The best we can do are studies like this:
Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular diseaseResults: 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.
This meta-analysis was not a Randomized Controlled Trial (RCT), even in the short term. This was a meta-EPI Study. Meta-EPI studies prove nothing. They are great for coming up with new hypothesis, but have major flaws for the type of research that is generally accepted as good science. Meta-analysis - Wikipedia, the free encyclopedia BTW, this study only looked at saturated fat intake, not total fat intake.
Studies Proving The Safety and Efficacy of the Low Carb Diet
The devil's in the details. Here is a summary of the first few studies quoted on that website:
First Quoted Study: Low-Fat Dietary Pattern and Risk of Cardiovascular Disease:The Women's Health Initiative Randomized Controlled Dietary Modification Trial Barbara V. Howard et al. JAMAVol. 295 No. 6, February 8, 2006
Quote on that webpage: Over a mean of 8.1 years, a dietary intervention that reduced total fat intake and increased intakes of vegetables, fruits, and grains did not significantly reduce the risk of CHD, stroke, or CVD in postmenopausal women.
Important study content/results: Reduced Fat intake from 38.8% fat to 6yr observed 28.8% Fat. No Where near the 10% of fat demonstrated by Ornish.
Interesting finding not told on Website: "Compared with those in the entire comparison group, a trend was observed toward reduction of CHD risk among those in the intervention group who reached the lowest levels of saturated fat and trans fat or the highest intakes of vegetables and fruits." AND "Collectively, these analyses, despite their inherent limitations, suggest that a diet lower in saturated and trans fat intake and higher in intakes of vegetables and fruits and polyunsaturated fat than what was achieved in this trial might show significant benefit in preventing CHD."
NET NET: The study pointed at confirmation of low-fat impact on CHD
Second Quoted Study: Low-Fat Dietary Pattern and Risk of Treated Diabetes Mellitus in Postmenopausal Women.The Women's Health Initiative Randomized Controlled Dietary Modification Trial. Lesley F. Tinker et al. Arch Int Med. Vol. 168 No. 14, July 28, 2008.
Quote on that webpage: None
Important study content: [FONT=verdana, arial, helvetica, sans-serif]A low-fat dietary pattern among generally healthy postmenopausal women showed no evidence of reducing diabetes risk after 8.1 years.[/FONT]
Interesting finding no told on Website:[FONT=verdana, arial, helvetica, sans-serif]Trends toward reduced incidence were greater with greater decreases in total fat intake and weight loss.[/FONT]
NET NET: The study pointed at confirmation of low total fat positive impact on Diabetes. (not sure why they included this on the website in the first place).
Third Quoted Study: Weight and Metabolic Outcomes After 2 Years on a Low-Carbohydrate Versus Low-Fat Diet: A Randomized Trial Gary D. Foster et al. Annals of Internal Medicinevol. 153 no. 3 147-157 Aug 3, 2010.
Quote on that webpage: A 2010 Study Finds Low Carb Diet Beats Low Fat at Improving Health Long Term. Tlow-carbohydrate diet group had greater increases in high-density lipoprotein cholesterol levels at all time points, approximating a 23% increase at 2 years.
Important study content: Again, another study at 30% or less, not 10%.
Interesting finding not told on Website: This study only measures RISK factors, not actual CHD (outcomes).
NET NET: HDL is part of reverse cholesterol transport. When you eat more saturated fat and dietary cholesterol, your body makes more HDL to remove it. Eating a stick of butter will raise HDL, but butter is not heart- healthy. Pfizer discontinued a study of its drug, torcetrapib, which raised HDL but actually increased risk of cardiac events. I'm not buying this one.
I'll stop there, I think one needs to dig deeper into the results of the studies to understand how the study was constructed and the actual findings before accepting a website that lists the studies as supporting an argument...
The lead in sentence says "Following a low-carb diet, even for only two days a week, was better than following a calorie-restricted diet every day for losing weight and lowering insulin levels, which are both associated with lower risks of breast and other cancers. Ok, this only says it is better than a calorie restricted diet. Again, the findings and recommendations for weight loss, cancer prevention and lower incidence of CHD is to have a low fat <10%, plant based diet. There are no calorie restrictions to the recommendations. This also doesn't demonstrate that LCHF diet is heart healthy or cancer limiting.
I love this one and I was waiting for someone to bring it up....Here is the author in an hour and 16 minute presentation on youtube....You can do a randomized controlled experiment for about a year, then measure markers for heart disease. That was what was done in this experiment:
Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women, March 7, 2007, Gardner et al. 297 (9): 969At 12 months, secondary outcomes [risk factors] for the Atkins group were comparable with or more favorable than the other diet groups.
The Battle of the Diets: Is Anyone Winning (At Losing?) - YouTube
Here are the significant points he makes during his speech:
1) 15:00 His primary outcome was weight change. Not a big deal, but I'm not arguing that you won't lose weight on LCHF diet, I'm arguing whole health.
2) 17:00 at 8 weeks the Ornish group were at 21% Fat and at 6 months and 1 year, they were 29% fat. There is no way that this is a demonstration that Atkins outperforms Ornish on any level. Ornish is clearly a 10% fat advocate. At best, with that mix of Carbs/Fat, it is a demonstration that Atkins outperforms the national guidelines. [Note that the baseline diet was 35% fat...so the comparison is to a shift of 35% fat to 29% fat ("low carb") vs. 35% fat to 46% fat (Atkins).]
At this point, the game is over. This is not a comparison of Atkins (LCHF) and Ornish (LFHC). There is no conclusion you can make from this study about the weight loss, heart benefits or cancer benefits of either.
But, the biggest issue I have with this study...
27:30 It was not a controlled study and the author admits that the study showed that "If you buy this book from the book store, this is what is likely to happen...One is more controlled and one is more public health oriented, we picked the public health oriented approach"
This is the most damning admission of the tape.He is admitting that it is a test of whether people can follow the advice, not a test of the impact of the dietary approach on weight loss (primary outcome).
This is just bad science and even worse mis-representation of secondary outcomes...it did not demonstrate that the Atkins diets were better or comparable than the others. It didn't test the others, it didn't even control them, it tested them against what people's interpretations of them were!
T-Al...all due respect, but...This is just bad science and even worse mis-representation of secondary outcomes...it did not demonstrate that the Atkins diets were better or comparable than the others. It didn't test the others, it didn't even control them, it tested them against what people's interpretations of them were!
Most of what you have presented are reasonable science misrepresented by the LCHF proponents as supporting the cause, when in fact, the tests are not valid test of the Ornish approach...all are high fat (20-30%) content tests. Nor is it a demonstration of the health benefits of LCHF beyond weight loss.
Some of it proves nothing or are too narrow (ie. the meta-epi).
Some of it is interesting social commentary that might prove it is hard to get people to maintain a low-fat (<10%) diet, but in no way demonstrates the heart health or cancer reducing capabilities of the dietary approach.
I'll still stick by the original Thread Title....The Danger of Low Carb Diets.
and oh BTW....
Bacon!
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