Human clinical research indicates that foods high in protein can provide weight loss help (Medical References 1, 2). There are several reasons: Foods high in protein are typically nutrient dense, meaning that small amounts provide high levels of nutrients. This helps one to obtain adequate amounts of nutrients with less caloric intake.
Also, foods high in protein have been reported to make one feel full (Medical References 1, 3, 4). It has been reported that eating protein-rich foods in greater amounts may also be associated with reduced abdominal fat (i.e. “belly fat”) as part of total overall weight loss (Medical Reference 5). Eating them in combination with exercise has been shown to help improve body composition (Medical Reference 6).
Soy foods like bars and shakes are an easy and convenient way to include foods high in protein in your diet. Such items have been shown to be beneficial for weight loss help. Studies have reported that soy foods in the form of a meal replacement product help reduce body weight, fat mass, and waist size (Medical References 7-9). Like other foods high in protein, soy makes you feel full (Medical Reference 10). They also typically have low glycemic index values (Medical Reference 11, 12), which help avoid rapid blood sugar spikes. Adding them to a diet often reduces the amount of refined carbohydrates, which have been suggested to lead to overeating (Medical Reference 13).
While adding high protein foods to your diet has benefits for body weight control, not all are the same. Soy is considered a high-quality protein based on its high digestibility in the digestive tract and colon, bioavailability of its amino acids, and its nitrogen content. The amino acid pattern (Medical Reference 14) provides adequate levels for normal growth and development. Based on protein digestibility scores, soy achieves a score of 1.0, the highest possible and on par with other similar sources like egg white and milk. Therefore, soy provides a healthy and effective way to include foods high in protein in your diet. Include physical activity and a good multivitamin under the direction of your doctor when dieting.
References
1. Halton TL, Hu FB. The effects of high protein diets on thermogenesis, satiety and weight loss: a critical review. Journal of the American College of Nutrition 2004; 23:373-385.
2. Hu FB. Protein, body weight, and cardiovascular health. American Journal of Clinical Nutrition 2005; 82(Suppl):242S-247S.
3. Weigle DS, Breen PA, Matthys CC, Callahan HS, Meeuws KE, Burden VR, Purnell JQ. A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight despite compensatory changes in diurnal plasma leptin and ghrelin concentrations. American Journal of Clinical Nutrition 2005; 82:41-48.
4. Johnston CS, Day CS, Swan PD. Postprandial thermogenesis is increased 100% on a high protein, low fat diet versus a high carbohydrate low fat diet in healthy young women. Journal of the American College of Nutrition 2002; 21:55-61.
5. Merchant AT, Anand SS, Vuksan V, Jacobs R, Davis B, Teo K, Yusuf S for the SHARE and SHARE-AP Investigators. Protein intake is inversely associated with abdominal obesity in a multi-ethnic population. Journal of Nutrition 2005; 135:1196-1201.
6. Layman DK, Evans E, Baum JI, Seyler J, Erickson DJ, Boileau RA. Dietary protein and exercise have additive effects on body composition during weight loss in adult women. Journal of Nutrition 2005; 135:1903-1910.
7. Deibert P, Konig D, Schmidt-Trucksaess A, Zaenker KS, Frey I, Landmann U, Berg A. Weight loss without losing muscle mass in pre-obese and obese subjects induced by a high-soy-protein diet. International Journal of Obesity 2004; 28:1349-1352.
8. Allison DB, Gadbury G, Schwartz LG, Murugesan R, Kraker JL, Heshka S, Fontaine KR, Heymsfield SB. A novel soy-based meal replacement formula for weight loss among obese individuals: a randomized controlled clinical trial. European Journal of Clinical Nutrition 2003; 57:514-522.
9. Fontaine KR, Yang D, Gadbury GL, Heshka S, Schwartz LG, Murugesan R, Kraker JL, Heo M, Heymsfield SB, Allison DB. Results of a soy-based meal replacement formula on weight, anthropometry, serum lipids & blood pressure during a 40-week clinical weight loss trial. BMC Nutrition Journal 2003; 2:14-20.
10. Eisenstein J, Roberts SB, Dallal G, Saltzman E. High-protein weight-loss diets: are they safe and do they work? A review of the experimental and epidemiologic data. Nutr Rev 2002; 60:189-200
11. Blair RM, Henley EC, Tabor A. Soy foods have low glycemic and insulin response indices in normal weight subjects. Nutrition Journal 2006; 5:35.
12. Foster-Powell K, Holt SHA, Brand-Miller JC. International table of glycemic index and glycemic load values: 2002. Am J Clin Nutr 2002; 76:5-56.
13. Ludwig DS, Majzoub JA, Al-Zahrani A, Dallal GE, Blanco I, Roberts SB. High glycemic index foods, overeating, and obesity. Pediatrics 1999; 103:E26.
14. Kolar CW, Richert SH, Decker CD, Steinke FH, van der Zanden RJ. “Isolated Soy Protein”, Chapter VIII in “New Protein Foods”, Vol. 5, Seed Storage Proteins, ed. Altschul AA, Wilcke HL, Orlando: Academic Press, 1985.