Marissa Gruber Rossana Ruvalcaba Kayla VanderKam

Taran Lent & Marie Kirsch

WHEY VS.

SOY

What’s the Difference?• Whey is a component of

cow's milk that is isolated in the standard cheese-making process.

• Soy protein comes from soybeans-a plant source

Whey Protein Soy Protein

Which One Is Better?

• Studies are trying to determine which one is really more beneficial when it comes to weight loss .

• Both claim to be better than the other

• The 5 journals were studies on overweight people

“Whey Protein but Not Soy Protein Supplementation Alters Body Weight and Composition in Free-Living Overweight

and Obese Adults”David J. Baer, Kim S. Stote, David R. Paul, G. Keith Harris, William V. Rumpler, and Beverly

A. Clevidence

Double-Blind, Randomized Clinical Trial

The objective was to determine the effect of consumption of supplemental whey protein, soy protein, and an isoenergetic amount of CHO on body weight and composition in free-living overweight and obese but otherwise healthy participants

They used 90 overweight and obese participants.

Each person was randomly assigned to one of three groups:

• Group 1 was given Whey Protein

• Group 2 was given Soy Protein• Group 3 was given isogeneric

amounts of CHOThe study lasted 23 weeks.

Each supplement provided ~56 g/d of Protein.

Each participant consumed a beverage twice a day containing 1670 kJ/d.

Body weight and composition data were obtained monthly.

Dietary intake was determined using 24 hour recalls that were collected every 10 days.

The ResultsAfter 23 weeks:

body weight of the WP participants were lower by 1.8kg, than the group consuming CHO

Lean body mass did not differ but waist circumference was smaller in participants consuming the WP than the other two groups

After 6 Months: There was a significant difference in body

weight and fat mass between over weight and obese adults who consumed supplemental WP compared with those who consumed isoenergetic CHO.

The difference in body weight was associated with a decrease in fat without an effect on lean mass.

The experiment has low reliability and validity due to the fact that the subjects were only followed for 23 weeks with some continuing through a full 6 months

Without controlling the subjects diets and only supplementing protein into their diets twice a day, it would take much longer than 6 months to see real effects

“Weight loss without losing muscle mass in pre-obese

and obese subjects induced by a high-soy-protein diet”

P Deibert, D König, A Schmidt-Trucksaess1, K S Zaenker, I Frey, U Landmann and A Berg1

Randomized, controlled study

Started with 90 participants

BMI’s of between 27.5 and 35

Estimate the efficacy of a high soy protein and low fat diet in weight lose but no muscle mass loss

Three Groups: Lifestyle education group.

-3 teaching session twice a month -They were given nutritional counseling a

moderate fat, balanced diet

Substitution diet group -Given two soy-yoghurt-honey replacements

for their food for the first 6 weeks

Substitution diet with physical activity group-Same diet of the substitution diet group -60 minute physical activity twice a week

•Results:At the end only 83 people completed

the study 6 monthsThe BMI dropped for all three groups Lifestyle education group lost least

weight than the other two groupsHigh soy protein and low fat diet lost

more weight than just following a conventional diet

All 3 groups kept their muscle mass

Critical Review

German authors for a university

How much soy protein is needed to actually achieve weight loss

Not enough people

Male/ female?

“Comparison of the effects of cows’ milk, fortified soy milk, and calcium supplement on weight and fat

loss in premenopausal overweight and obese women”

Sh Faghih, A.R. Abadi, M. Hedayati, S.M. Kimiagar

100 women

20-50 years old

Overweight or obese

25-40 BMI

The Groups: All were asked to consume 500 fewer kcals/day

Control groupSupplement group:

• 800mg/day calcium carbonate

Milk group: • 3 servings of low-fat milk

per daySoy group:

• 3 servings of calcium fortified soy per day

After 8 weeks …

85 women finished

Weight, BMI, waist circumference, and hip circumference were re-measured

“The greatest changes were seen in the high dairy group in all variables.” [3]

Critical Review

This study was non-bias and there was no conflict of interest.

Problem: 8 weeks was too short!

Longer studies have shown some conflicting results.

“A whey-protein supplement increases fat loss and spares lean muscle in obese subjects: a randomized human clinical

study”By: Joy L Frestedt, John L Zenk, Michael A Kuskowski, Loren S Ward and Eric D Bastian

Objective: test the effects of a whey supplement on weight loss

Randomized, double blind, 12-week study

158 obese subjects

Independent variable: the consumption of the whey supplement

Dependent variable: weight loss, body fat loss, and lean muscle mass retention

Whey supplement group lost more body fat and retained more lean muscle mass

The Study

CRITICAL REVIEW Funded by Gianbia Nutritionals

Inc.

Use of completers vs. responders data

“Acute effects of whey protein isolate on cardiovascular risk factors in overweight, post-menopausal women”

Sebely Pal, Vanessa Ellis, Suleen Ho

OVERWEIGHT AND OBESE POST-MENOPAUSAL WOMEN ARE HIGHLY SUSCEPTIBLE TO CARDIOVASCULAR DISEASEINVESTIGATE THE ACUTE EFFECTS OF DIETARY WHEY PROTEINS ON LIPIDS

GLUCOSE AND INSULIN THREE-WAY CROSSOVER DESIGN 21 OVERWEIGHT OR OBESE, POST-MENOPAUSAL

WOMEN RANDOMIZED CONSUME EITHER 45 GRAMS SODIUM CASEINATE

OR 45 GRAMS OF A GLUCOSE CONTROL WITH A BREAKFAST MEAL

The Results No significant change between groups in postprandial

incremental area under the curve for: total cholesterol low density

lipoprotein, high density lipoprotein, non-esterified

fatty acids, Apo B48, insulin

leptin

There was a significant decrease in the appearance of triglycerides in the blood by 21% and 27% after consuming the whey meal compared to control and casein meals

It can be suggested that a single dose of whey protein can decrease arterial exposure to smaller triglyceride-enriched lipoprotein particles compared to the glucose and casein

Whey protein has beneficial effects

Effective supplement that can help lower the triglycerides in the body which consequently lowers the chances of postprandial lipidemia

CRITICAL REVIEW

Conclusion1 invalid study concerning the whey protein supplement

The short duration of time spent on the research

Longer trials were necessary

More control over what the subjects were or were not eating

Whey protein was seen in an overall positive light

Soy- not as good as whey