Rice Protein Supplements: Yea or Nay?

For various reasons, a lot of people use rice protein as a substitute for whey protein. A new study suggests rice-based products might be as effective as whey if the dosage is right.

For numerous reasons, people might avoid standard whey protein supplements. Perhaps they are vegans or experience a digestive problem with whey. Whatever the reason, these protein seekers go elsewhere for their supplements. Lately, informed consumers have been shying away from soy, perhaps wary of its chemicals that may mimic hormones in the human body. It seems that rice protein has become more and more popular in just the last few years.

Of course, there’s no good reason at all to use it if it isn’t effective. You may as well just save your money. Until a study this month in Nutrition Journal, no research had been done comparing high protein supplementation of whey versus rice protein supplements. While some studies had been performed on the general topic, none of the supplements could be considered high-protein products. In this study, however, the rice protein supplement used contained 48 grams of protein.

Before I go into the findings, it’s important to discuss why to even bother with more studies about protein. We already know from prior research that whey beats rice protein when used in smaller doses. It seems pointless to try again. However, the researchers theorized that it was the amino acid leucine that made the difference.

Leucine is a nutrient that supports muscle growth, and it has an upper and lower threshold. Below the right amount, which is thought to be about 1.7 grams, it doesn’t have its full effects. More leucine, even double that dose, has no further effect. Since most supplements have about 20 grams of protein per serving, and many studies are done with about that much, if you were to compare rice to whey, whey would win. But that would possibly only be because it would contain more than the above-mentioned leucine threshold at that quantity, while rice protein would have less.

Indeed, with the 48 grams of protein in the supplements used in this study, the researchers ultimately found no difference in a host of factors between the two supplements. The perceived soreness, recovery levels, lean mass, strength, and power of the participants all went up while body fat went down.

Now, this seems like a slam dunk for rice protein, and that was the conclusion of the study. However, I’m not satisfied. This study had no control, which is a big problem with its design. The participants met with dieticians and strictly controlled their diets. While that’s all well and good, the protein content of their diet alone was 25% of their calories, which is substantial. For most people that means over 100 grams of dietary protein per day, and perhaps over 150 grams, although the study doesn’t give us any clues beyond this. Add on a 48 gram protein supplement, and you’d probably experience good results no matter what kind of product it was.

If you’re going to take rice protein supplements, they certainly seem effective when compared to whey, as long as you consume them in a high enough quantity and with an otherwise high protein diet. However, you may find that your results are just as good with a high protein diet alone.


1. Jordan Joy, et. al., “The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance,” Nutrition Journal 2013, 12:86.

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