Dukan Diet

It was about time for an artificial sweetener update, wasnt it?

Alright, I have to admit I am not following the artificial sweetener scene closely enough to have heard about SUCRAM, an artificial sweetener that is composed of saccharin (a classic) and neohepseridin dihydrochalcone, the new kid on the blog, which is yet not officially approved by either the FDA or it European equivalent o be used in the processed junk, most people call "food", these days. If we put some faith into the latest study investigating the effects of this agent, which is apparently already heavily used in animal feeds in Europe it does yet "dramatically reduce enteric disease" and "enhance growth performance in early-weaned piglets." (Daly. 2014)

Whether and to which extent these beneficial effects on gut health are mediated by changes in the gut microbiome is yet still uncertain; and since "uncertain" is a word scientists dont like, Kristian Daily and his colleagues from the University of Liverpool conducted a study to find out, whether the non-negligible health benefits would be brought about by AI <> gut interactions.
To this ends, the scientists employed a DNA-based pyrosequencing technology to investigate the changes in the intestinal microbiota of piglets weaned to a diet supplemented with either a natural sugar, lactose or said artificial sweetener (SUCRAM)

Figure 1: Total and lactobacillus OTU4228 concentrations in piglets on hydrolzysate carbohydrate diet without sweeteners, with lactose or SUCRAM diets and corresponding concentration of lactic acid in the caecal contents (Daly. 2014)

As you can see in Figure 1, both, the addition of lactose and the saccharin/NHDC mix lead to dramatical increases in the caecal Lactobacillus population and could well explain the previously reported "pro gut health" effect of SUCRAM in piglets (Vente-Spreeuwenberg. 2004; Pierce. 2006)

But thats obviously not all thats news-worthy!

I did after all promise you news on products you may be using, as well - aspartame and acesulfame-k, to be precise. Now, while the former is a constant target of public (mostly broscientific) criticism, the latter has been a thorn in my side ever since I have started investigating artificial sweeteners.

Lean more about the "Gut Type Diet" - No Fad, Guaranteed!

And while previous studies only suggested that the effects of acesulfam-k on the pancreas could have pro-obesogenic consequences, a recent model experiment from the Louisiana State University appears to finally prove that acesulfam-k may actively promote the deposition of body fat in the presence of insulin resistance.

Ok, the results have been derived in a Caenorhabditis elegans, a "worm", but one that has long and actually surprisingly successfully been used as a "model for studying the basic biology of obesity" (Jones. 2009) - I know, I am not convinced either, but if the results do actually translate to humans, this would be major (bad) news for the food industry.

In view of the fact that most companies have been pulling acesulfame-k from their products over the past years, anyway, I would not discard the findings Jolene Zheng et al. present in their latest paper in Chemico-Biological Interactions as meaningless, not despite, but rather because a scientists from PepsiCo was part of the research team which observed these significant increases in intestinal fat (=visceral fat of the worm) when the critters were fed with acesulfam-k sweetened coke.
References: 

• Payne, A. N., C. Chassard, and C. Lacroix. "Gut microbial adaptation to dietary consumption of fructose, artificial sweeteners and sugar alcohols: implications for host–microbe interactions contributing to obesity." Obesity Reviews 13.9 (2012): 799-809.
• Pierce, K. M., et al. "The effect of lactose and inulin on intestinal morphology, selected microbial populations and volatile fatty acid concentrations in the gastro-intestinal tract of the weanling pig." ANIMAL SCIENCE-GLASGOW THEN PENICUIK- 82.3 (2006): 311.
• Jones, Kevin T., and Kaveh Ashrafi. "Caenorhabditis elegans as an emerging model for studying the basic biology of obesity." Disease models & mechanisms 2.5-6 (2009): 224-229.
• Vente-Spreeuwenberg, M. A. M., et al. "Effect of dietary protein source on feed intake and small intestinal morphology in newly weaned piglets." Livestock Production Science 86.1 (2004): 169-177.

High intensity thinking - intelligent weight loss workouts

Its almost 2014! Actually it is already 2014; at least for my friends in the "Far East" (HAPPY NEW YEAR!) and thus almost too late for the annual "I want to lose weight" new years resolution. Ok, you as a SuppVersity reader should actually know better, but just in case you are still planning to make the weight loss happen solely by increasing your workout volume, I would suggest that you replace some classic HIT training with the revolutionary HIT 2.0 - high intensity thinking regimen (warning: doing this too often may actually build more brain than muscle mass ;-). 

Well,... now that I take a closer look at the results of this recent study from the University of Quebec here,  I have to realize that this will only work if you are a man. But dont worry, I am pretty sure there is something to be learned for the ladies in the last SuppVersity article of 2014, as well ;-)

All jokes aside, your brain is a sucker for energy!

I guess you will be familiar with the over-cited fact that "the human brain is only 2% of the weight of the body, but it consumes about 20% of the total energy we need every day"... I know thats boring, but actually thats quite an important point, because it tells you that your brain is not just a sucker for energy, but also a sucker for new information, which will in turn increase the energy requirements of the insatiable heap of neurons in your skull. Why? Well, our brains need energy to process each and every of these information chunks - max. 30W per opeartion, if the currently heralded estimations are correct. I know that sounds tremendously much, but if we performed only one of these operations per minute, you would hardly burn the energy equivalent of 1/25 of a 70-85% chocolate bar during your high intensity thinking sessions.

Against that background its all the more impressive that Emilie Pérusse-Lachance and her Canadian colleagues were able to measure a significant increase in energy expenditure, when they had their 35 subjects (22 men and 13 women; aged 24 ± 3 years) read a 10-page text and write a summary of approximately 350 words using a computer in the "mental work condition" of their study.

Figure 1: Energy expenditure in kcal/45min in the control and the mental work condition, left; energy intake during the buffet ca. 15min after the control and mental work condition, right (Pérusse-Lachance. 2013)

If you take a look at the data in Figure 1, you will also notice that the scientists original hypothesis, which was that they would observe a similar hyperphagic (=hunger ➲ increased energy intake) response to in the "mental work" condition as Chaput et al. who conducted two very similar studies in 2007 and 2008.  The actual study outcome does yet tell a different story: While the female study participant did in fact supercompensate for the extra-energy they had to spent, when they were not watching TV and lolling around like in the control condition, the men were probably so immersed in their thoughts that they simply forgot to eat... ok, I guess you already realized that this was an ad-hoc hypothesis to make sure you dont realize that neither I nor the scientists have any clue what the underlying reasons of this sex-difference were.

I would even guess that the women did not even notice that they were overcompensating. If you take a look at the subjective hunger scores that have been assessed by seven visual analogue scale questionnaires the participants had to fill...

1. at the beginning (T-60/60 minutes before the buffet), 
2. after the experimental session (T-15/15 minutes before the buffet), and 
3. after the buffet-type meal (T0, T60, T120, T180, and T240).

...those will tell you that the ladies either claimed to, or actually werent more hungry than in the control condition. In view of the irrefutable evidence that they still ate more (see Figure 1) this may look awkward. When its all said and done, these contradictory result does yet only confirm that you cannot trust people, when they tell you "I am never hungry and actually dont eat that much.... I have really NO clue where that belly comes from". This may even be their own perception, but that does not change that it is usually not in line what happens at the buffets, dinner tables and - most importantly - during the snack breaks people take during not after their high intensity thinking regimen all over the world.
References:

• Chaput, J. P., & Tremblay, A. (2007). Acute effects of knowledge-based work on feeding behavior and energy intake. Physiology & behavior, 90(1), 66-72.
• Chaput, J. P., Drapeau, V., Poirier, P., Teasdale, N., & Tremblay, A. (2008). Glycemic instability and spontaneous energy intake: association with knowledge-based work. Psychosomatic medicine, 70(7), 797-804.
• Pérusse-Lachance, E., Brassard, P., Chaput, J. P., Drapeau, V., Teasdale, N., Sénécal, C., & Tremblay, A. (2013). Sex Differences in the Effects of Mental Work and Moderate-Intensity Physical Activity on Energy Intake in Young Adults. ISRN Nutrition, 2013.

The meager increase in glucose disposal observed in the study at hand is not likely to do anything, but be good for another confusing graph on the label of the licensees first OpunDia powered supplements.

Against the background that insulin still has a pretty bad rep, it is actually quite funny that its fiercest enemies and most loyal followers of low-carb diets are usually the guys and girls who spent tons of money on 100% useless "insulin mimetics". Insulin mimetics like the cactus extract thats at the heart of a recent study by Louise Deldicque, Karen Van Proeyen, Monique Ramaekers, Ivo Pischel, Hartwig Sievers and Peter Hespel? Or could it be possible that Opuntia Ficus-Indica is the infamous exception that proves the rule?

To answer this question, it is obviously necessary that we take a closer look at the corresponding paper in the Journal of the International Society of Sports Nutrition (ISSN). I mean, it is not impossible that this is finally the "next big thing" weve all been waiting for, right?

Leucine + Herb = Win?

Before we dig further into the methods and results of the study, it it probably suitable for me to tell you about the meaningful letters "™" behind the word OpunDia and the openly declared competing interests of Ivo Pischel and Hartwig Sievers.
Enough of the foreplay , though, lets finally take a look at the design and the results of this human trial that was conducted by the Exercise Physiology Research Group at the Department of Kinesiology of KU Leuven in Belgium (Deldicque. 2013).

There were 11 male subjects who participated in the study. All were physically active and the mean age was 21.1 ± 0.9 years. With a body weight of of 74.5 ± 4.2 kg and a VO2 max (~fitness level) of 65 ± 4 ml·min/kg), they are probably representative of the average, but not necessarily the extra-extraordinaire trainee.

After the usual pre-testing procedures, the guys were randomized to receive either

• 1,000 mg LUVOS Heilerde serving as placebo (PL),
• 1,000 mg OpunDia™ (OFI), 
• 3,000 mg of old-fassioned leucine (LEU), or 
• 1,000 mg OpunDia™ + 3,000 mg leucine (OFI+LEU).

After each of the four randomized cross-over testing session that involved 30min of rather casual cycling at 70% of the predetermined VO2 max (90-100 rpm) the subjects received capsules containing one of the above formulations and the 75g of glucose that were used for the oral glucose tolerance tst.. Needless to say that all capsules had identical appearance and the number of capsules ingested was the same for each condition.

It works, but what does that tell us?

In a previous trial, Van Proeyen et al. had already observed that the ingestion of an identical supplement stimulates the peripheral disposal of oral glucose before and after exercise in healthy men. If you will, you may thus call the study at hand a follow up, which did - what a surprise (!) - confirm the effects of OFI and a certain, but not exactly impressive synergism between the plant extract and everyones favorite amino acid leucine, one of the branched chain amino acids and, as SuppVersity readers know, likewise highly pro-insulinogenic (learn more about leucine).

Figure 1: Glucose and insulin iAUC after oral glucose test performed subsequent to the ingestion of PL, OFI, LEU or LEU + OFI supplement and 30min of "cardio" at 70% of the VO2max (left); glucose levels in the 2h after the OGGT (Deldicque. 2013)

A cursory glance at the data in Figure 1 should suffice to see two things: (1) There was the expected / hoped for synergistic effect of leucine and OFI, but (2) only the OFI-only trial, and not the combination treatment led to significant reductions in the area under the glucose curve.

Is this even an improvement?

Remember that chromium picolinate can worsen the insulin sensitivity in  healthy non-diabetic, non-obese individuals by up to 25% | learn more

"Add Leucine and get more insulin, but a lower rate of glucose disposal"... I dont know what youd say, but for me this sounds much like insulin resistance or lets rather say no improvement over the provision of OFI alone. The first take-home message is thus that the addition of leucine to OFI may produce a synergistic effect on insulin, the effect we are actually looking for, namely the increase in blood glucose uptake and glycogen synthesis is however absent. And whats more, neither I nor the researchers have an real clue as to what it is that triggers the short-lived increase in insulin production thats brought about by the ingestion of 1,000mg Opuntia Ficus-Indica extract.

Accordingly, it is very difficult to give any prognosis whether more would help more, or the whether wed see similar detrimental effects as with chromium upon dose escalation.
References:

• Manders RJ, Little JP, Forbes SC, Candow DG. Insulinotropic and muscle protein synthetic effects of branched-chain amino acids: potential therapy for type 2 diabetes and sarcopenia. Nutrients2012. 4:1664–1678.
• Van Loon LJ, Saris WH, Kruijshoop M, Wagenmakers AJ. Maximizing postexercise muscle glycogen synthesis: carbohydrate supplementation and the application of amino acid or protein hydrolysate mixtures. Am J Clin Nutr. 2000,72:106–111.
• Van Loon LJ, Kruijshoop M, Verhagen H, Saris WH, Wagenmakers AJ. Ingestion of protein hydrolysate and amino acid-carbohydrate mixtures increases postexercise plasma insulin responses in men. J Nutr. 2000, 130:2508–2513.
• Van Proeyen K, Ramaekers M, Pischel I, Hespel P. Opuntia ficus-indica ingestion stimulates peripheral disposal of oral glucose before and after exercise in healthy men.Int J Sport Nutr Exerc Metab 2012,22:284–291
• Wiese J, McPherson S, Odden MC, Shlipak MG. Effect of Opuntia ficus indica on symptoms of the alcohol hangover. Arch Intern Med. 2004 Jun 28;164(12):1334-40.