New Low Carb Study Misses The Point
A new study, "Low carbohydrate-high protein diet and incidence of cardiovascular diseases in Swedish women: prospective cohort study" published in the British Medical Journal (BMJ.com) misses the point of low carb diets. The study is based off of interviews with 43 396 Swedish women, the interviews gauged their total carbohydrate and protein intake over 15.7 years and measured the incidence of cardiovascular diseases.
One would think that such a study might help settle the question of whether a low carb diet was heart healthy or not, but this type of study totally misses the point of going low carb (especially primal low carb). The study basically graded each person on a combined carb / protein score, additive combination of these variables (low carbohydrate-high protein score, from 2 to 20).
Anyone familiar with one of these diets can probably see several flaws in the study design.
- Carbs must be reduced to a level where the body burns fat for energy.
- All carbs are treated the same vegetable carbs and candy bars are equal
- Most of these people weren't even on low carb diets, they simply measured intake
- There was no associated exercise plan with the diet
- No mention of vitamins or supplements, which are often needed on a true low carb diet
- No mention of the quality of meat, e.g. grass-fed beef
- Etc., etc. (post the flaws that you find)
Reducing carbs on a SAD diet by 10% does very little good. Often times people feel hungry and have less energy unless they reduce their carbs to the point where they burn fat for energy (100 grams of carbs and below) so they make up for this with high sugar. Additional sugar on a high protein diet is already known to be bad for cardiovascular health.
This study is already being used by the MSM to bash the Primal/Paleo diets, Atkins, etc.
There are a lot of issues with this "study." they followed the women for 15 years but only measured their "reported" carb/protein intake for the first six months. "The women's food habits were not tracked long-term but did provide researchers a snapshot in time." In my opinion, six months does not give you a snap shot of a 15 year span of time. Ridiculous!
Originally Posted by Czalmanoff
Exactly. I noticed the same thing in the study report. When you think of this, along with the timeframe -- the study was started in 91 or so -- it's certainly possible that the cohort made a move to a more-carb-based diet (as the rest of the industrialized world was doing during that time frame).
As has been noted ad nauseum here and elsewhere, observational cohort studies like these are next-to-worthless when it comes to leading to sound dietary advice.
I think that Gary Taubes noted in one of his books, referencing another book, that observational studies like these USED to be used primarily to find topics to actually RESEARCH. In other words, conclusions would not be drawn from a study like this; rather, scientists would observe a correlation, come up with a hypothesis, and then design an experiment (double-blind randomized if possible!) to TEST it. Only after THAT would advice be given.
If a diet can't supply what you need, then ipso facto it would seem to be inappropriate.
Originally Posted by MN_John
However, I'm far from convinced that low-carb diets necessitate supplements. And historically populations that have eaten this way -- Eskimos, Plains Indians, African cattle herders, Siberian tribesmen, etc. -- haven't had access to vitamin pills and other supplements.
Of course, people who've been metabolically-damaged might benefit from some supplements as part of a repair process that also involves low-carb eating. And certain supplements -- for example, fish oil (if you don't get enough fish) and vitamin D3 (if you don't get outdoors enough) -- are helpful for anyone ... but that would include people on diets that were not low in carbohydrate.
He speaks to that here:
Originally Posted by Rosencrantz1
+1 -- thanks!
Originally Posted by Lewis
True enough, especially with your caveat. True low carb (like week one on Atkins) aren't designed to be long term, it would be a real chore to try to get proper nutrition without some vegetables. The Primal Diet is a lot easier in this regard. In regards to your caveat, I had some major IBS / SIBO for many years (now 95% fixed through anti-Candida supplements, stomach acid enzyme replacement, and nutrients). This left may very deficient in several nutrients. So I for one am now eating right and taking nutrients (along with stomach acid enzyme replacement which was probably the root of many of my problems). Its just a hack, much like paleo man didn't have access to an appendicectomy I for one will utilize this modern treatment if needed. We may also stumble across super human nutrition where we're healthier than either modern man or paleo man, I'm fine with that.
Originally Posted by Lewis
I'm glad to find you guys discussing this study! The German media gave it more coverage than it normally would to a topic like this, and I have been wanting to read the study, but haven't found the time yet. My husband has been eating primal for almost two weeks, and seeing this study in a lead article gave him some doubts. I'm glad to have something to respond with even before I find the time to read about the study in detail!
I soooooo disagree. Fruits and veges are hugely overrated for nutrition. In fact I've all but eliminated them from my diet. I would say I get MAYBE one serving a day of vegetables since I use them for flavoring only. Eat some eggs and liver on a weekly basis....you'd be better off.
Originally Posted by MN_John
That said I'm also NOT very low carb. I fall in the 50-70g range all from sweet potatoes and some raw or cultured dairy right now.
BTW, I'm not exactly attacking veges and fruits....I just think they are more of a "break even" thing than an actual necessity.
Last edited by Neckhammer; 06-29-2012 at 08:46 PM.
Tags for this Thread