VeganHealth.org Update: Near Vegan Diet Improves Type 2 Diabetes
This study is from 2011 from the Czech Republic. I mentioned it in my post on the type 2 diabetes treatment meta-analysis that I made last week, Type 2 Diabetes Meta-Analysis: What Happened to the Vegan Diet?
I’ve also had it in my nutrition queue to read for some time. In fact, anyone who’s read this blog for awhile might be wondering how many studies might actually be lurking in my nutrition queue! Well, I’m happy to report that I had over 200 emails (many with studies attached) to go through last Friday at noon and it’s now down to 81. So, I’m catching up!
The reason this study got buried is because the abstract calls the diet “vegetarian,” rather than “vegan.” But once you read the study, you see that the “vegetarian” diet contained no animal products except for a maximum of one serving of low-fat yogurt per day – that’s as vegan as the diet used in Dean Ornish’s heart disease reversal study.
In fact, it makes me rethink that type 2 diabetes meta-analysis – they said they only included diets that had been studied at least twice, saying that only one study looked at a vegan diet and one looked at a “vegetarian” diet when in reality, the diets were virtually both vegan given that people in these studies tend to cheat a little bit anyway. Oh, well.
One difference is that the diet in the PCRM study was about 21% fat, whereas the diet in the Czech Republic study was…drum roll please…38% fat!
The rest of this post is copied from the blurb I just added to Type 2 Diabetes and the Vegan Diet at VeganHealth.org:
In 2011, researchers from the Czech Republic studied a vegetarian (near-vegan) diet compared to a conventional (control) diet for type 2 diabetes (1). The study tested only diet for 12 weeks and then combined diet and exercise for another 12 weeks. Animal products were limited to maximum of one portion of low-fat yogurt a day. The calories in both diets were limited (as distinct from the PCRM studies in which the vegan diet was unlimited in calories). The vegetarian diet was about 38% fat.
The vegetarian diet group had a greater reduction in diabetes medication (43% vs. 5%), HbA1c, waist circumference, and body fat. LDL cholesterol went down 8% in the vegetarian group only, but HDL cholesterol went up in the control group. Exercise caused the positive differences for the vegetarian diet to be even greater and also raised the HDL in the vegetarian group.
The authors stated:
Several possible mechanisms may explain the beneficial effects of a vegetarian diet: higher intake of fibre, lower intake of saturated fat [and a higher polyunsaturated and saturated fatty acid (P⁄S) ratio], higher intake of non-heme iron and reduction in iron stores, higher intake of vegetable protein in place of animal protein, higher intake of antioxidants and plant sterols. A vegetarian diet was reported to reduce intramyocellular lipid concentrations and this, together with the effect on visceral fat which we observed, might be responsible for a substantial portion of the effect of a vegetarian diet on insulin sensitivity and enzymatic oxidative stress markers.
And, oddly enough:
Especially during exercise, it became evident in our trial that it was easier for subjects to follow a vegetarian diet than a conventional diabetic diet.
And I’m happy to report that VeganHealth.org’s Type 2 Diabetes and the Vegan Diet section is now up to date. I am considering paring down a lot of the details on that page – if anyone has read it and has an opinion on if you prefer the details or would like to see them pared down quite a bit, please let me know in the comments here. Thank you!
Reference
1. Kahleova H, Matoulek M, Malinska H, Oliyarnik O, Kazdova L, Neskudla T, Skoch A, Hajek M, Hill M, Kahle M, Pelikanova T. Vegetarian diet improves insulin resistance and oxidative stress markers more than conventional diet in subjects with Type 2 diabetes. Diabet Med. 2011 May;28(5):549-59. | Link
February 13th, 2013 at 7:47 am
You asked whether we thought it would be helpful to pare down the information on your Type 2 Diabetes page. My own opinion is that it would be best to leave the information there.
When I read your Type 2 Diabetes page, I don’t see anything that stands out as “I think it would help me a lot in reading your page if you changed this”. The tables are helpful. If I want to find information quickly, I can find it easily. If I want more information, the information is there.
My eyes did skip over a little of the information in the PCRM 2004-05 study, especially where the text talks about some of the information that’s in the table. But I don’t know that taking that out is called for, since the information is easy to skip, and it might possibly be helpful to someone.
If I had to find something to criticize, possibly you could add a table for the Czech Republic study, and include in the table the fact that the later part of the study included exercise. But it really seems quite clear the way you have that information now.
Basically, I’d say that article is good the way it is.
February 13th, 2013 at 9:20 am
Thanks, Cobie!