Resistant Starch (RS4) Reduces Waist Circumference, Body Fat % & Cholesterol Levels in Lean and Obese Individuals in Randomized, Double-Blind Cross-Over Human Study

Effortlessly lean with RS4? Probably not, but if you're into flour-based products it may be for you.

Some things are resistant to being forgotten. D-aspartic acid, for example, is useless and still around. RS-4, on the other hand, has more or less disappeared from the market, when Scott Connely's and Vince Andrich's last project Myotropics shut its doors. What? Oh, you don't even know what I am talking about? Well, RS-4 stands for "resistant starch", type 4. It's usually made from waxy maize starch, but will - due to its unique structure pass through the gut, more or less undigested (learn more).

RS-4 will thus end up in the long intestine, where it is eaten up and being fermented by your bacterial subtenants to eventually be absorbed by your gut in the form of short-chain fatty acids - readily available energy with a metabolic twist - a twist due to which they will also function as signalling molecules in the complex concert that is your metabolism.
These short chain fatty acids have gained quite some attention in the science community as of late and are touted to be the potential anti-obesity + pro-metabolic agents of the future.

Accordingly, seasoned SuppVersity veterans, who obviously knew everything I've just explained, already, will no be surprised to hear that Sailendra N. Nichenametla and colleagues claim in their latest paper in the peer-reviewed scientific journal Molecular Nutrition & Food Research that

"...[i]ncorporation of RS4 in routine diets could offer an effective strategy for public cardio-metabolic health promotion." (Nichenametla. 2014)

The researchers from the South Dakota State University base their assessment of the health benefits of RS-4 flour (Fibersym, MGP Ingredients, Atchison, KS - a sponsor of the study), which had been replaced at a 30% v/v ratio in the diets of 86 US adults with and without metabolic syndrome... and as you can see in Figure 1, the effects of this minimal change were quite enormous.

Figure 1: Changes in HDL and body comp. in all subjects, and subjects w/ and w/out metabolic syndrome (Nichenametla)

The addition of 30% RS-4, which is an artificial resistant starch that passes the small intestine undigested to end up in the large intestine, where it is converted to short-chain fatty acids by the gut bacteria (learn more), to the flour the subjects had to use for all their flour-based products, induced a 7.2% reduction in total cholesterol, a 5.5% reduction of non-HDL, and a 12.8% reduction in HDL of which I must say that I am obviously not happy with it.

Interestingly, similar changes were not observed in normal-weight (No-MetS) individuals. For them the resistant starch worked its previously reported fat loss wonders and lead to reductions in waist circumference (-2.6%; p=0.02) and percent body fat (-1.5%; p=0.03) over the course of the 12 weeks they spent in the active arm of the study (remember: We're dealing with a cross-over study with a two week washout in-between).
References:

• Nichenametla, Sailendra N., et al. "Resistant starch type 4‐enriched diet lowered blood cholesterols and improved body composition in a double blind controlled cross‐over intervention." Molecular nutrition & food research (2014).