The study, led by researchers from the Iran University of Medical Sciences and the Tehran University of Medical Sciences, compared the benefits of whey protein concentrate (WPC) with soy protein isolate (SPI) in a 12-week randomized, double-blind clinical trial.
Pitting whey and soy head-to-head
Most people know whey as a supplement – especially for sports. However, whey, a byproduct in cheese production, has three main forms: Isolate, concentrate, and hydrolysate. Whey protein concentrate is what's left after the liquid portion of milk has been filtered out. When the concentrate is processed further, it then turns into whey isolate. (Related: Great Benefits of Whey Protein for Muscle Building.)
Soy protein isolate, on the other hand, is a low-calorie supplement known to be high in protein and is used in gaining muscle. However, whether or not it should be used has become a topic of debate, as it is an allergen found in processed food such as bread and other baked goods.
"There is a lot of controversy around soy and whether or not it’s good for you," added health coach Devi Moss in an article on Wellness Today. "But the real controversy lies with soy isolate, not whole food soy products like organic tofu and whole soybeans."
To compare the two, the team recruited employees from a power plant in Karaj City. In total, 52 people volunteered to take part in the three-month trial. The participants were all men, with ages ranging from 30 to 65 years, and had a body mass index (BMI) between 25 to 40 kilograms per square meter.
According to the National Health Institutes of Health, a healthy BMI should fall between 18.5 to 24.9. If a person's BMI is between 25 to 29.9, he is considered overweight, while a person with a BMI of 30 and above is considered obese.
During the study, the participants were randomly assigned to drink water that had either 65 g of WPC or 60 g of SPI dissolved in it 30 minutes before they had lunch. Before the clinical trial had begun, researchers measured the participants' lipid profile and fasting blood sugar – and took them again after its conclusion. These were taken to measure the amount of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) – also known as "bad" and "good" cholesterol, respectively. Their systolic and diastolic blood pressures were recorded as well, and after every two weeks during the study.
After the study, the researchers found that while both presented benefits on the lipid profile and blood pressure of the participants, those who took WPC had better results.
"This study demonstrated that long-term supplemental preloads with [whey protein isolate] and SPI can improve metabolic risk factors associated in overweight and obese individuals, though the effects of WPC were higher," the researchers concluded.
They discovered that those who took WPC had a significant drop in their diastolic blood pressure, wherein higher readings could be a risk factor for cardiovascular disease. They also reduced their apolipoprotein B and LDL levels, based on the lipid profile. Meanwhile, apolipoprotein A-I and HDL, indicators of good heart health, increased.
Learn more about the other benefits of whey protein by following SupplementsReport.com today.
Sources include:
Please contact us for more information.
