ONLINE DRIVERS MEDIA

Todays SuppVersity News will provide you with "confirmation" rather than "innovation", I suppose

With my recent article on the non-existance of protein-related osteoporosis (read more) and the short news post about the unique satiating effects of protein snacks (read more), theres been quite some protein lovin here at the SuppVersity as of late. Usually, I would try to avoid having yet another "protein article" in the same week, but for the most recent study on "Dietary Protein Distribution", I will make an exception and I bet, you wont mind! Why? Well, what about what follows the "Dietary Protein Distribution" in the title of said paper?

"...Influences 24-h Muscle Protein Synthesis in Healthy Adults"

By now, you may feel reminded of a recent review by Alan Aragon and Brad Schoenfeld (Aragon. 2013), the results of which (learn more) are not refuted by the results of the study at hand.
What the study does tell us, is simple: "The consumption of a moderate amount of protein at each meal stimulated 24-h muscle protein synthesis more effectively than skewing protein intake toward the evening meal." (Mamerow. 2014)

In other words: Dont cram all your protein into one meal!

I guess in view of past articles on related topics (e.g. "2x40g, 4x20g or 8x10g of Whey? Which Feeding Strategy Yields the Greatest Net Protein Retention?" | read more; or "Protein Timing Reloaded: A Reminder on the Importance of Repeated 20g Pulses for Optimal Protein Synthesis" | read more), this insight is not really going to surprise you.

Figure 1: Fractional protein synthesis at breakfast (left), when the difference was most pronounced (+30%) and rel. calculated 24h fractional protein synthesis (right) with EVEN vs. SKEWED protein distribution (Mamerow. 2014)

What may surprise you, though is the simple fact that this study, which was a joint venture of scienfitsts from the Division of Rehabilitation Sciences at the Department of Nutrition and Metabolism, and Department of Internal Medicine at the University of Texas Medical Branch and the Department of Food Science and Human Nutrition at the University of Illinois at Urbana (Mamerow. 2014) is the first study to conclusively show that spreading a relatively high protein intake (1.2g/kg body weight) across the day is superior to the large steak the average intermittent faster may be washing down with a triple protein shake in the evening.

With an average age of 37 years the 8 healthy, normal-weight adult men and women who participated in the study at hand were neither rodents, nor elderly individuals, and - contrary to what you may expect if you look at the italicized names of the Institutions the scientists who were involved in this study are working at - they were not in need of rehabilitation after an injury - they were average Joes (n = 5) and Janes (n= 3).

This is not about rodents, elderly people or injured athletes

As you can see in the overview in Table 1, the subjects consumed three square meals, i.e. breakfast, lunch and dinner in the course of the 7-day study period. The previous reference to intermittent fasting is thus obsolete - eating a minimal amount of protein in the morning and at noon is after all very different from eating nothing at all. 

Table 1: Seven-day mean energy and macronutrient intake in healthy adults consuming diets with an EVEN or SKEW protein distribution (Mamerow. 2014)

As the scientists point out, the total 24-h protein, carbohydrate, and fat consumption in the SKEW and EVEN conditions was not different.

"Both diets exceeded the RDA for protein [0.8 g/(kg d)] by ~50%. The SKEW diet met the RDA for protein during the evening meal alone. In all versions of the EVEN and SKEW menus used in this study, the animal-to-vegetable protein ratio was ~2:1." (Mamerow. 2014)

By using a 7-d crossover feeding design with a 30-d washout period, the scientists were thus able to measure the influence of protein timing, on the changes in muscle protein synthesis.

The latter was measured thrice, i.e. after each of the three meals, and used to calculate the twenty-four-hour mixed muscle protein fractional synthesis rates on days 1 and 7 after the ingestion of EVEN-ly or SKEW-edly distributed protein diets.
Reference:

• Aragon, Alan Albert, and Brad Jon Schoenfeld. "Nutrient timing revisited: is there a post-exercise anabolic window?." Journal of the International Society of Sports Nutrition 10.1 (2013): 5.
• Mamerow, Madonna M., et al. "Dietary Protein Distribution Positively Influences 24-h Muscle Protein Synthesis in Healthy Adults". J. Nutr. January 29, 2014 jn.113.185280 [ahead of print].

Is there something to the good vs. bad fat shenanigan, after all?

Only recently scientists from the Texas Tech University report that a PUFA-rich high-fat meal led to a greater diet-induced thermogenesis in normal-weight premenopausal women compared with SFA- or MUFA-rich high-fat meals.

Reason enough to take a closer look at this and previous studies investigating the diet-induced thermogenic effects of PUFA-, MUFA- and SFA-rich meals and to conduct a reality check wrt to the question whether these differences actually matter - I mean, will you get and stay lean by upping your PUFA intake? Lets take a look!
In the initially mentioned study, Hui C. Clevenger, Amanda L. Kozimor, Chad M. Paton and Jamie A. Cooper explored the effect of three HF meals enriched with different fatty acids (MUFAs, PUFAs or SFAs) on metabolism in premenopausal women of normal weight. In that, the metabolic parameters of interest included postprandial energy expenditure (EE), which is then used to calculate DIT, and substrate oxidation, which included respiratory exchange ratio (RER), fat oxidation and carbohydrate (CHO) oxidation.

Based on previous research in men of normal weight, the Texas Tech researchers hypothesized that the diet induced thermogenesis (DIT) and fat oxidation would be the highest after the PUFA- and MUFA-rich meals and lowest after the SFA-rich meal in premenopausal women - a result of which you already know that it was only partly confirmed.

Figure 1: Diet-induced thermogenesis and respiratory exchange rate (higher RER = lower fatty acid oxidation vs. higher CHO oxidation) in the 5h after the test meal (Clevenger. 2014)

The data in Figure 1 does after all tell you that the expected MUFA-induced increase in diet-induced thermogenesis did not occur. PUFAs, on the other hand did the job, Clevenger et al. expected them to do. They increased the DIT by an ostensibly whopping 14% over the DIT the scientists observed in response to the ingestion of the high MUFA and SFA liquid meals that had been prepared with the same base of 8 fl oz (237 ml) of chocolate Ensure(R) with soy lecithin and Nesquik (R, but contained different additional dietary fatty acids added depending on the treatment condition:

• Table 1: Liquid meal nutrient composition breakdown (Clevenger. 2014).

  The PUFA-rich meal was ‘base’ plus sunflower oil and flaxseed oil, with 42% of total energy coming from PUFA.
   
• The MUFA-rich meal was ‘base’ plus canola oil and extra virgin olive oil, with 42% of total energy coming from MUFA.
  
  
• Finally, the SFA-rich meal was ‘base’ plus butter, coconut oil and palm oil, with 40% of total energy coming from SFA. 

As the data in Table 1 indicates, the nutrient profiles didnt differ much. The fatty acid composition, on the other hand did, with the SFA meal being the only one with measurable amounts of Butyric, Caprioc, Caprylic, Capric, Lauric, Myristic and Hepatedic acid. Fatty acids of which previous research indicate that they induces an obesity-linked proinflammatory gene expression profile in adipose tissue of subjects at risk of metabolic syndrome (van Dijk. 2009).

High MUFA diets, on the other hand, have been shown to potentiate the effects of weight loss in obese NIDDM patients (Low. 1996). They are the major group of fatty acids in the one oil, everyone appears to agree that its health (Olive oil). And last but not least, even the allegedly unhealthy omega-6s have been shown in randomized controlled to reduce liver fat and modestly improve metabolic status, without weight loss, when compared to high saturated fat diets (Bjermo. 2012).

All of these effects / this evidence could potentially be more important than the increase postprandial thermogenesis in the study at hand - so the ultimate question is: Does DIT even matter?
References:

• Bjermo, Helena, et al. "Effects of n? 6 PUFAs compared with SFAs on liver fat, lipoproteins, and inflammation in abdominal obesity: a randomized controlled trial." The American journal of clinical nutrition 95.5 (2012): 1003-1012.
• Clevenger, Hui C., et al. "Acute effect of dietary fatty acid composition on postprandial metabolism in women." Experimental physiology (2014): expphysiol-2013.
• Westerterp, Klaas R., et al. "Dietary fat oxidation as a function of body fat." The American journal of clinical nutrition 87.1 (2008): 132-135.