Is Rice the New Whey to Go? Study Shows, Rice and Whey Protein Equally Support Mass & Strength Gains + Fat Loss in Resistance Trained College Aged Men

Is rice the new whey to go? Or just something for the average vegan who realizes that he cannot go without protein?

While I personally considered the study on phosphatidic acid (yesterday's news) most interesting, there were many other presentations on the ISSN conference that are worth mentioning (note: my buddy Sean Casey is about to write a summary of his stay there, I'll let you know on Facebook, when he is done). The full-text papers are however only available for one of the studies, which has likewise been conducted by Joy et el. (see PA study). The fulltext just appeared on the website of the Nutrition Journal (Joy. 2013) and is also the topic of today's SuppVersity article that revolves - once again - around the question, whether whey really is the whey (all typos intended) to go.

Is there any other way than whey?

The study was conducted with 24 college-aged, resistance trained males (21.3 ± 1.9 years, 76.08 ± 5.6 kg, 177.8 ± 12.3 cm) who had trained at least three times per week for the past 6 months. The guys were randomly and equally divided into two groups, consuming either 48 g of rice or whey protein
isolate (isocaloric and isonitrogenous) right after the workout.

Figure 1: Amino acid profile of the rice and whey protein isolate (Joy. 2013)

"The program  was designed to train all major muscle groups using mostly compound movements for the  upper and lower body. The programmed, non-linear training split was divided into  hypertrophy days consisting of 8–12 RM loads for 3 sets, with 60–120 seconds rest and  strength days consisting of 2 to 5 RM loads for 3 sets for all exercises except the leg press  and bench press which received 5 total sets. Weights were progressively increased by 2–5%  when the prescribed repetitions could be completed. All training sessions were closely monitored by the researchers to ensure effort and intensity were maximal each training session." (Joy. 2013)

The subjects s trained 3 days per week for 8 weeks as a part of a daily undulating periodized resistance-training program (see quotation. above). Ratings of perceived recovery, soreness, and readiness to train were recorded prior to and following the first training session. The changes muscle thickness was determined by ultrasonography and DEXA scans were used to assess the body composition.

Put your prejudices aside, results are the only thing that counts

Moreover bench press and leg press for upper and lower body strength were recorded during weeks 0, 4, and 8 and statistically analyzed, when the study was over.

Figure 2: Bench pres, leg press strength and peak power before, during  and after the study (Joy. 2013)

As you can see the strength increases did not differs significantly when you compare the rice to the whey protein. Against that background it is actually not very surprising to see that the same was the case for the change in body composition, I plotted in figure 3.

Figure 3: Baseline and post study body composition and muscle size (Joy. 2013)

If we take another look at the amino acid profile in figure 1, it does yet become evident that the effects could have been different, if the subjects stuck to only 50% of the amount of protein they ingested in the study at hand.

Figure 4: Theoretical model for protein dose and the anabolic response (adapted from Joy. 2013)

"In the present study, the combined muscle thickness of the VI and VL increased in both the rice protein (0.2 cm) and whey protein (0.5 cm) conditions. Lean body mass increased in the rice protein condition by 2.5 kg, and it also increased in the whey protein condition by 3.2 kg. Combined bench press and leg press 1-RM strength increased in the rice protein condition by 76.4 kg and in the whey protein condition by 89.5 kg. However, no significant differences were observed between the two conditions for any measure. The collective findings of our study and others suggests that as the amount of protein consumed increases, the importance of the relative leucine content of the protein diminishes" (see figure 4; Joy. 2013).

Overall, the study at hand does therefore provide reliable evidence that people with dairy intolerance fair pretty well with a rice protein - as long as they make up for the 30% lower leucine content.

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Rice protein can be a valuable replacement for whey. Just remember, you cannot live on rice alone, because you would be running the risk of not getting adequate lysine, which would heavily compromise the nitrogen balance increase anxiety, impaired catecholamine release, etc. (cf. Albanese. 1941; Smriga. 2000, 2002, 2003). As part of a regular diet, rice proteins do yet in fact appear to be a viable (yet higher to dose) alternative to whey protein, which has be the way been shown to help with blood lipid management, only recently (Yang. 2013).

References:

• Albanese, Holt LE, Brum-Back JE, Hayes M, Kajdi C, Wangerin DM. Nitrogen Balance in Experimental Lysine Deficiency in Man. Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, NY). Royal Society of Medicine. 1941; 48(3): 728-730. 
• Joy JM, Lowery RP, Wilson JM, Purpura M, De Souza EO, Wilson SM, Kalman DS, Dudeck JE, Jäger R. The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance. Nutr J. 2013 Jun 20;12(1):86.
• Smriga M, Mori M, Torii K. Circadian release of hypothalamic norepinephrine in rats in vivo is depressed during early L-lysine deficiency. J Nutr. 2000 Jun;130(6):1641-3. 
• Smriga M, Kameishi M, Uneyama H, Torii K. Dietary L-lysine deficiency increases stress-induced anxiety and fecal excretion in rats. J Nutr. 2002 Dec;132(12):3744-6.
• Smriga M, Torii K. L-Lysine acts like a partial serotonin receptor 4 antagonist and inhibits serotonin-mediated intestinal pathologies and anxiety in rats. Proc Natl Acad Sci U S A. 2003 Dec 23;100(26):15370-5.
• Yang L, Han G, Liu QH, Wu Q, He HJ, Cheng CZ, Duan YJ. Rice protein exerts a hypocholesterolemic effect through regulating cholesterol metabolism-related gene expression and enzyme activity in adult rats fed a cholesterol-enriched diet. Int J Food Sci Nutr. 2013 Jun 14.
   

Diet Deoptimization with Rice Protein: Less Weight Gain, Lower Cholesterol and Fatty Acid Synthesis - So What?

Image 1: Rice protein power - I'd bet a pouch of casein protein that this Chinese "body builder" must have eaten plenty of rice protein. I mean, check out how ripped he is! Update: Garymar informed me that this is a Japanese comedian called Yoshiaki Yamane - sorry, my mistake ;-)

The "real" supplement news have been pretty slow as of late - there have not been any, to be precise. Unless you are interested in yet another study on an exotic African or Asian root or herb and its "antioxidative activity" in the petri-dish, you would probably have been as bored as I was by the latest articles in respective journals. And if Stephen Watt had not asked my opinion on a study my colleagues over at ergo-log had in the news, as of late, I would probably have ignored a "rodents on rice protein" study from the Department of Food Science at the School of Food Science and Engineering of the Harbin Institute of Technology in Harbin, China (Yang. 2012) - the headline ergo-log headline "Fat percentage too high? Add rice protein to your shake", did however look too intriguing not to take another look at a study, the abstract of which I did not really suggest that rice protein would actually help you burn body fat.

Rice for lactose intolerant vegetarians and poor Chinese farmers ...

What the scientists from the Middle Kingdom had done, was to feed three groups of 7-week (adolescent*) male Wistar rats on diets containing either

• 22.9% casein - could the one in your cheap protein blend, after all it was from China ;-),
• 23.2% rice protein A - extracted from Oryza sativa L. cv. Longijng by alkaline / acid extraction, or
• 23.2% rice protein E - extracted by sigma aldrich via heat stable starch degradation

The total experiment lasted two weeks and aside from the protein faction, the composition of the chow, to which the rodents had ad-libitum (=whenever they wanted) access was identical.

Figure 1: Blood amino acid concentrations in rodents fed casein or rice protein (the figures in % represent the relative level of the given amino acid in the RP-A group compared to the casein group, e.g. RP-A rats had 92% of the amount of Alanine, the casein rats had in blood; left; data adapted from Yang. 2012) and absolute and relative amounts of amino acids in casein and rice protein (open pars indicate relative amount of the given amino acid in rice compared to casein, eg. 172% more alanine in rice than in casein protein; data adapted from Morita. 1997)

The latter, i.e. the being identical, cannot be said of either of the amino acid structure of the casein and rice protein (figure 1, right), nor the amino acid contents and ratios in the plasma of the lab animals (cf. figure 1, left), though.

... yet not necessarily for aspiring physical culturists!

The muscle head and fitness fanatic that you probably are, you will certainly already have realized that the level of BCAAs in the blood of the animals on the rice protein diets was 26% and 29% (RP-A and RP-E, respectively) lower than that of the rodents receiving the casein chow. An observation which was to be expected in view of the -27% lower BCAA concentration in rice compared to the casein protein (Morita. 1997; figure 1, right). Astonishingly, this does not hold true for all other amino acids, for glycine, for example, the amino acid content in the source was 2x higher, the serum levels were yet only 15% higher than in the casein group (note: the casein chow was enriched with cysteine, in this particular case a comparison of source vs. serum levels would thus be futile).

Figure 2: Fecal analysis (left) and changes in body weight, as well as absolute body fat percentage and food intake  (right) of adolescent male Wistar rats (data calculated based on Yang. 2012.

If you also take into account that a 7-week old male rat has just become fertile (at about the 6th week of its life), think of yourself, your brother or son at the age of 16y, of what you / he ate and how much weight he gained and then take another, closer look at the data in figure 2 I would say that the question whether switching from casein to rice protein would actually help you lose fat appears more than warranted. After all, we are looking at weight (not fat!) gain in a period of growth (the body fat levels of the rodents, were 2.1%, 1.9% and 1.8%, respectively, cf. figure 2, right). If the latter were totally absent, you would call that "failure to thrive" - a term that would not strictly apply in the situation at hand, though.

In view of the huge fecal loss of dietary fat (+60% over casein) and dietary protein (+145% in the RP-A and +217% in the RP-E group), the 5% lower fat free mass in the rodents on the rice protein diets and the reduced ALT and AST levels, which are not necessarily indicative of "improved liver function", but rather of a reduced hepatic protein turnover, it seems as if "Rice protein reduces body weight gain, energy availability and storage in adolescent rodents due to its lower digestibility" would have been a more appropriate title for the study than "Rice protein improves adiposity, body weight and reduces lipids level in rats through modification of triglyceride metabolism" - and alas, a very similar study, yet without the data on the "body weight gain", has already been published by the same research group in 2011 (Yang. 2011).

Diet-deoptimization a novel weight loss strategy?

Image 2: I guess the Chinese have heard how the Americans got rid of their corn and soy and do now try to pull off a similar "it's good for your health"-stunt with rice protein as the US did with their "healthy" vegetable oils and soy proteins.

Personally, I would yet suggest to call the study "diet-deoptimization by the provision of less palatable, less digestible chow to rodents", but I guess in that case the results would never have made it to ergo-log and subsequently to the SuppVersity. It was thus pretty clever to disguise what could simply be a natural (side) effects of a reduced energy intake (-5%) and reduced energy absorption (-60% from fat and -145% or -217% from protein), i.e. a reduction in fatty acid synthesis and an increase in breakdown (you may remember that even rodents need fat, right?), as evidence that (I quote from the conclusion) "rice protein can modify triglyceride metabolism, leading to an improvement of body weight and adiposity" - wouldn't you agree?

In the end, the protein and fat wasting effects of the rice protein diets could even explain the advertised "beneficial" impact on the lipid profile with VLDL/HDL ratios of 0.19 and 0.16 vs. 0.24 in the RP-A and RP-E groups vs. the casein group. Whether similar effects could be observed in a human trial and whether these "improvement" (from one end of the normal range to another) would decrease the risk of heart disease, is yet questionable. Moreover, the reduction (or replacement; not necessarily the complete elimination) of the whopping ~60% carbohydrate content (488g cornstarch and 100g succrose per kg of chow) in the diet and/or the replacement of the pro-inflammatory soy-bean oil with e.g. olive oil would probably elicit way more beneficial effects on the triglyceride and blood glucose level in humans than a switch from casein to indigestible and in rodent-terms obviously non-palatable rice protein.