VN: Blood Lipids and Vegetarian Diets (2009)
Vegetarian Diets and Blood Levels of Cholesterol and Triglycerides
Observational research has often found an association between vegetarian dietary patterns and various health benefits. However, in part because of variations within vegetarian diets, the findings are sometimes blurred or inconsistent (see Types of Vegetarian Diets).
In order to control for the wide variation in types of vegetarians diets and practices, we limited our evidence analysis to clinical trials in which vegetarian dietary patterns were controlled and in which vegetarian diets were used as a therapeutic intervention.
So, the evidence analysis here focuses on the therapeutic use of a vegetarian diet to treat different disease states. Because the research and findings were slightly different, we created separate evidence analysis questions for each of the items below:
- Total Cholesterol
- Low Density Lipoprotein Cholesterol
- Very Low Density Lipoprotein Cholesterol
- High Density Lipoprotein Cholesterol.
Studies in a Ten-Year Time Span
We identified 14 intervention studies (published between 1997 and 2007) in which a vegetarian diet was used therapeutically for any one of the following conditions: To manage cholesterol, to manage diabetes type 2 risk factors, to treat obesity or to treat fibromyalgia symptoms.
In nine of these studies blood lipid management or CVD risk factors were one of the main targets of the diet intervention:
- Agren JJ, Tvrzicka E, 2001 (negative quality)
- Barnard ND, Scialli AR et al, 2000 (positive quality)
- Barnard, Cohen et al, 2006 (positive quality)
- Dansinger ML, Gleason JA et al, 2005 (positive quality)
- Daubenmier JJ, Weidner G, 2007 (neutral quality)
- Hunt JR, Matthys LA et al, 1998 (neutral quality)
- Jenkins DJ, Kendall CW et al, 2003 (vn) (positive quality)
- Jenkins DJ, Kendall CW, et al, 2003 (Metabolism) (neutral quality)
- de Mello VD, Zelmanovitz T, 2006 (positive quality).
In five other studies, the target of the intervention was something other than blood lipid management or CVD risk factors (e.g., obesity treatment, diabetes management, etc.). However, because these studies involved the therapeutic use of a vegetarian diet and because they also reported blood lipid outcomes, they were included in the analysis.
- Burke LE, Hudson AG et al, 2007 (positive quality)
- Burke LE, Styn MA et al, 2006 (positive quality)
- Kaartinen K, Lammi K et al, 2000 (negative quality)
- Mahon AK, Flynn MG et al, 2007 (positive quality)
- Stephenson TJ, Setchell KD et al, 2005 (neutral quality).