Comment by driverdan | Hacker News Reader

Comment by driverdan | Hacker News Reader

While interesting this is a highly flawed study. It should be considered preliminary with more properly controlled followup studies.

1. No control group

You need to have a control group that continues eating a standard healthy diet that includes animal products. The 11% who were non-adherent could have been eating unhealthy diets which contributed to their instances of CAD. Without a control it could have just been eating a healthy diet that helped, not the exclusion of animal products.

2. No blinding

Of course a food consumption study is nearly impossible to double blind but at the very least the researchers could have been blinded. This also requires a control group.

3. Self-reported data

While it's very tough to get anything other than self-reported data for long term food consumption, it makes it far more likely that the participants will report inaccurate or incorrect data. Results tend to be biased because participants don't want to let researchers down and lie about adherence.

You are right on all three points!

The most interesting item in the article, was this, "We referenced the plummeting death rates from strokes and heart attacks in Norway during World War II when the German occupying forces confiscated their livestock, limiting Norwegians to plant-based nutrition.15"

I didn't know about this. This might be the only reliable evidence of the efficacy of plant based diets we have so far? I don't know the mindset of Norwegians back then concerning health, so I don't think the Placebo Effect played much of a role in final statistics, and they must have been under a lot of stress. I couldn't find the footnote 15, but will look harder.

I don't remember the source, but I read an article a couple of years ago that linked that statistic of plummeting death rates in Norway during WW2 to high consumption of cod liver oil, which apparently was readily available. Take that as you will.

"This study had several limitations. First, it included self-selected, very deter- mined patients. Without a control group, it is challenging to establish causality and as- sess how much of the observed changes are specifically due to the diet. Only some of the observed beneficial outcomes may have been due to the diet. This study was not pro- spectively randomized. Nevertheless, this fact does not detract from proof of concept that major cardiovascular events occurred in probably <1% (and certainly <10%) of the entire adherent cohort, compared with 62% of the nonadherent cohort (TaBlE 2). These data convey a strong message of patients accepting empowerment to be the locus of control to arrest their disease and confirm that patients will adopt a significant lifestyle transition to plant-based nutrition to halt and regress what we believe is a largely food- borne illness.

The past several decades have witnessed a substantial and sustained reduction in CAD. Nevertheless, CAD remains the number one killer of women and men in this country. Thousands of stable patients having stents experience no reduction in major cardiac events.6 While drugs have some effects on disease initiation and progression, these in- terventions do not address disease causation. Not surprisingly, most patients experience disease progression, more drugs, more im- aging, repeat interventions, progressive dis- ability, and, too often, death from a disease of western malnutrition, the cause of which has been largely left untreated. We have in press several patient experiences that exemplify the repeated failure of present-day cardiac drugs and procedural interventions, and that confirm the capacity of whole-food plant- based nutrition to restore health in “there is nothing further we can do” situations.36 In summary, the present cardiovascular medicine approach tested beyond 40 years can neither cure the disease nor end the epi- demic and is financially unsustainable. The safety, diminished expense, and prompt, powerful, and persistent results in treating the cause of vascular disease by whole-food plant-based nutrition offer a paradigm shift from existing practice. We think the time is right for a controlled trial. But in the mean- time, the data are sound and strong enough that patients should be informed of this option."

Thanks for including that.

> These data convey a strong message of patients accepting empowerment to be the locus of control to arrest their disease and confirm that patients will adopt a significant lifestyle transition to plant-based nutrition to halt and regress what we believe is a largely food- borne illness.

In other words, they conclude that diet can impact CAD and some people will be willing to change their diet. No surprise there. The fact that the study was for plant-based nutrition holds very little relevance since there was no control group. It could simply be that people transitioned to a healthy diet. We can't know for sure without proper controls.

I don't think the effectiveness of a whole foods plant based diet is really in question here. There are enough robust studies showing that it prevents and reverses CAD (look for Dr. Dean Ornish and Dr. Collin Campbell).

Knowing that CAD is the number one killer in several countries, I am all for studies like this being published, even with the lack of formal control group, after all, the numbers are pointing in one direction. If I had heart disease, I would have liked to know about this data.

Nearly 100% of participants who changed their diet had no additional cardiac events; some even had measurable disease reversal. These were all sick people. The hard question is "What is a healthy diet that includes animal products?" This study doesn't address that interesting question but does demonstrate that if you eat a particular healthy diet that happens to not include any animal products, you won't die from heart disease. That's a profound result for the participants, with profound public health implications.

I don't know if it's highly flawed, though it does have the flaws you mention. The numbers may be true, but they don't smell right to me. 90% adherence for a significant change in diet for the long-term of three and a half years? Even for people who've had close shaves with death and those who have 'every intention' of following through, this seems absurdly high.

Similarly the marked difference in effects between the groups - two thirds of the non-adherent group versus a single case in the 177 adherents, in terms of having another event? It's not like the benefits of vegetarianism all arrive the following day - I would have thought there'd likely be a few more in the adherents group that had an event while they were still 'in transition'.

It may all very well be true, but it does smell a little funny.

Control and double blind studies are more important when the placebo effect and subjective outcomes are at play. Not necessary here. Everyone that follows a different diet would like to complain about that. You should have compared it to the paleo diet, or low-carb diet, or whatever. Show studies that those diets have similar effects and then they merit comparison.

Self reporting is an issue, but this is not the only type of study on the issue. It has been supported by international studies, animal testing, and countless studies about the health benefits of more fruits/vegetables and less meat.

My friend, (a scientist) wants to develop a pill that "triggers" the placebo effect (lets face it, its as effective as many drugs). Could you test that?

Sure, but you would just be testing it against other placebos. There has been work in this area. For instance getting a pill from a doctor is stronger than getting the same pill from a stranger. The look/cost of the pill affects it's strength, etc.

This post needs to be higher. Note the weasel-words about this being an adjunct to normal cardiovascular care:

>These patients with established cardiovascular disease (CVD) were interested in transitioning to plant-based nutrition as an adjunct to usual cardiovascular care.

In other words, this study cannot establish that the statins these patients were already taking didn't account for their perceived health benefits.

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