Overvekt er sjeldnere blant dem som spiser plantebasert enn befolkningen for øvrig. I snitt er det en vektforskjell på 7 kg hos menn og 3 kg hos kvinner mellom de som spiser utelukkende plantebasert og de som spiser gjennomsnittlig, der de som spiser plantebasert ligger nær opp til idealvekt. Forskning viser at dette i all hovedsak er relatert til kostholdet. Den samme gunstige effekten ser man hos barn.
Om overvekt og fedme i et globalt perspektiv: Obesity and overweight. World Health Organization, 2016. http://www.who.int/mediacentre/factsheets/fs311/en/
Om belgvekster for vektkontroll: Kim SJ, de Souza RJ, Choo VL et al. Effects of dietary pulse consumption on body weight: a systematic review and meta-analysis of randomized controlled trials. AJCN 2016; 103 (5):1213-23. http://ajcn.nutrition.org/content/103/5/1213.abstract
«Conclusions: The inclusion of dietary pulses in a diet may be a beneficial weight-loss strategy because it leads to a modest weight-loss effect even when diets are not intended to be calorically restricted. Future studies are needed to determine the effects of dietary pulses on long-term weight-loss sustainability.»
Her er flere vitenskapelige artikler.
Sara Ask, dietist, og Åsa Strindlund, nutritionist Vegetarisk mat är bra – även för små barn. Läkartidningen. 2014;111:CMEA Läkartidningen 11/2014
Lakartidningen.se 2014-03-11 (uppdaterad 2014-09-22)
«Ett högt intag av animalieproteiner, framför allt från mjölkprodukter, under de första levnadsåren kan bidra till ökad tillväxt och högre BMI i barndomen samt är relaterat till tidigare pubertet och ökad risk för övervikt och fetma senare i livet [26, 27].»
Ru-Yi Huang MD, MPH, Chuan-Chin Huang ScD, Frank B. Hu MD, PhD, Jorge E. Chavarro MD, ScD, Vegetarian Diets and Weight Reduction: a Meta-Analysis of Randomized Controlled Trials. Journal of General Internal Medicine July 2015. DOI 10.1007/s11606-015-3390-7
«Overall, individuals assigned to the vegetarian diet groups lost significantly more weight than those assigned to the non-vegetarian diet groups (weighted mean difference, −2.02 kg; 95 % confidence interval [CI]: −2.80 to −1.23). Subgroup analysis detected significant weight reduction in subjects consuming a vegan diet (−2.52 kg; 95 % CI: −3.02 to −1.98) and, to a lesser extent, in those given lacto-ovo-vegetarian diets (−1.48 kg; 95 % CI: −3.43 to 0.47).»
Hörnell A, Lagström H, Lande B, et al. Protein intake from 0 to 18 years: a systematic literature review for the 5th Nordic Nutrition Recommendations. Food Nutr Res. 2013;57. doi: 10.3402/fnr.v57i0.21083.
«In conclusion, the intake of protein among children in the Nordic countries is high and may contribute to increased risk of later obesity. The upper level of a healthy intake is yet to be firmly established. In the meantime, we suggest a mean intake of 15 E% as an upper limit of recommended intake at 12 months, as a higher intake may contribute to increased risk for later obesity.»
Günther AL, Remer T, Kroke A, et al. Early protein intake and later obesity risk: which protein sources at which time points throughout infancy and childhood are important for body mass index and body fat percentage at 7 y of age? Am J Clin Nutr. 2007;86:1765-72.
«A higher animal, especially dairy, protein intake at 12 mo may be associated with an unfavorable body composition at 7 y. The age of 5-6 y might represent another critical period of protein intake for later obesity risk»
Vergnaud A-C, Norat T, Romaguera D, Mouw T, May AM, Travier N, et al. Meat consumption and prospective weight change in participants of the EPIC-PANACEA study. Am J Clin Nutr. 2010 Aug;92(2):398–407.
«Our results suggest that a decrease in meat consumption may improve weight management.»
Tonstad S, Butler T, Yan R, Fraser GE. Type of vegetarian diet, body weight, and prevalence of type 2 diabetes. Diabetes Care. 2009;32:791–6.
Mean BMI was lowest in vegans (23.6 kg/m2) and incrementally higher in lacto-ovo vegetarians (25.7 kg/m2), pesco-vegetarians (26.3 kg/m2), semi-vegetarians (27.3 kg/m2), and nonvegetarians (28.8 kg/m2).
Prevalence of type 2 diabetes increased from 2.9% in vegans to 7.6% in nonvegetarians; the prevalence was intermediate in participants consuming lacto-ovo (3.2%), pesco (4.8%), or semi-vegetarian (6.1%) diets.
After adjustment for age, sex, ethnicity, education, income, physical activity, television watching, sleep habits, alcohol use, and BMI, vegans (OR 0.51 [95% CI 0.40–0.66]), lacto-ovo vegetarians (0.54 [0.49–0.60]), pesco-vegetarians (0.70 [0.61–0.80]), and semi-vegetarians (0.76 [0.65–0.90]) had a lower risk of type 2 diabetes than nonvegetarians.»
«The 5-unit BMI difference between vegans and nonvegetarians indicates a substantial potential of vegetarianism to protect against obesity. Increased conformity to vegetarian diets protected against risk of type 2 diabetes after lifestyle characteristics and BMI were taken into account. Pesco- and semi-vegetarian diets afforded intermediate protection.»
«Fish-eaters, vegetarians and especially vegans had lower BMI than meat-eaters. Differences in macronutrient intakes accounted for about half the difference in mean BMI between vegans and meat-eaters. High protein and low fibre intakes were the factors most strongly associated with increasing BMI.»
Flere studier er her
- Sabate J, Wien M: Vegetarian diets and childhood obesity prevention. Am J Clin Nutr 2010, 91(5):1525S-1529S;
- Farmer B, Larson BT, Fulgoni VL, et al. A vegetarian dietary pattern as a nutrient-dense approach to weight management: an analysis of the National Health and Nutrition Examination Survey 1999-2004. J Am Diet Assoc. 2011;111:819-27.
- Fraser GE: Vegetarian diets: what do we know of their effects on common chronic diseases? Am J Clin Nutr 2009, 89(5):1607S-1612S;
- Craig WJ: Health effects of vegan diets. Am J Clin Nutr 2009, 89(5):1627S-1633S;
- Craig WJ, Mangels AR: Position of the American Dietetic Association: vegetarian diets. J Am Diet Assoc 2009, 109(7):1266-1282;
- Dunham L, Kollar LM: Vegetarian eating for children and adolescents. J Pediatr Health Care 2006, 20(1):27-34;
- Newby PK, Tucker KL, Wolk A. Risk of overweight and obesity among semivegetarian, lactovegetarian, and vegan women. Am J Clin Nutr. 2005;81:1267–74.
- Key TJ, Appleby PN, Rosell MS. Health effects of vegetarian and vegan diets. Proc Nutr Soc. 2006;65:35-41.
- Kim MK, Cho SW, Park YK. Long-term vegetarians have low oxidative stress, body fat, and cholesterol levels. Nutr Res Pract. 2012;6(2):155-61.