Dukan Diet

Heme and Non-Heme Iron

Vegans can get sufficient iron from plants by eating those high in iron and eating foods like fortified cereals. Iron absorption will increase with the consumption of foods high in vitamin C at the same meal. To optimize iron consumption, grains and beans can be soaked to lessen phytate content. Tannins, antacids and soda should be avoided and calcium supplements should not be taken at mealtime.

Raw food vegans (especially pregnant women or women of childbearing age) may have a harder time getting sufficient iron, especially if on a 100% raw food diet. If you are 80% raw or less, consider supplementing your diet with high iron foods like cooked beans and taking all of the other precautions listed above.

Men and post-menopausal women should be careful not to supplement or eat too many iron-fortified foods unless they have iron deficiency anemia.

You as a SuppVersity reader should know that there is no "instant gratification" with  "doing cardio" and that doing it "in the zone" is totally 90s... 1990s, even ;-)

For decades, the "Fat Burning Zone" has been one of the holy grails of exercise sciences. Then somebody realized that maximizing the ratio of fat : glucose thats are being used as fuel during a workout doesnt really have an effect on weight loss and all of a sudden papers with titles like "Changes in peak fat oxidation in response to different doses of endurance training" (Rosenkilde. 2013) have become a rarity... although, if you look closely, you will realize that this is actually not another investigation into the realms of the "Fat Burning Zone", but an afford to quantify the effect of regular "cardio training" on your bodies ability to oxidize fat, instead of glucose.

Dont worry its not really about the "fat burning zone"

Luckily Rosenkildes most recent paper, which happens to be the third spinoff of the high (600kcal/day) vs. medium (300kcal/day energy expenditure from "cardio") training volume that already taught us (you can read more about the exact exercise protocol in the previous SuppVersity articles, below) ...

• Learn more about the "Fallacy of Working Out To Burn Calories"

  how futile it is to work out like a maniac if fat loss is your goal ("Some HIIT For Life & Less LISS For More! How to Burn 27,300 Kcal Extra W/out Losing a Single Extra Pound of Fat!" | read more) and 
• how messed up the die hard belief that "exercise" just makes you hungry actually is and what the effects of endurance exercise on appetite and energy intake are ("Exercise: Does It Really Make You Hungry? The More You Train, The Less Hungry You Are." | read more)

In this second serving of the data, we can now learn whether regular endurance training increases peak fat oxidation in a dose-dependent fashion.

Figure 1: Pre & post respiratory exchange ratio (lower value = higher ratio of fatty acid : glucose oxidation) in sedentary control and 300kcal/day group, left; changes in the expression of mitochondrial enzymes (Rosenkilde. 2013)

As you can see in Figure 1 the outcomes of the experiment were not exactly surprising: While there was a persistent increase in fatty acid oxidation and the expression of the facilitative mitochondrial complexes, i.e. enzymes in the mitochondrial respiratory chain, the daily endurance training volume (MOD: 300kcal/day vs. HIGH: 600kcal/day energy expenditure during endurance training) had no effect on the effect size.

So, if its not the volume, what determines the increase in fatty acid oxidation?

Rosenkilde have probably asked themselves something similar to the above, when they realized that there were no meaningful differences between the subjects in the medium vs. high dose cardio groups. The statistical analyses the researcher conducted did yet reveal, that

• VO2peak, generally regarded as a marker of cardio-respiratory fitness,
• fat free mass, the weight of everything (incl. bones, organs, etc.) thats not fat, 
• cycling efficiency, the power output at a given VO2 peak, and the
• mitochondrial complexes II–V, enzymes that facilitate the oxidation of fatty acids,

were all associated with higher increases in fatty acid oxidation, while the observed changes in fasting plasma insulin, glucose, FFA, or glycerol had no prognostic value with respect to the increase in fatty acid oxidation.
References: 

• Crane, J. D., MacNeil, L. G., & Tarnopolsky, M. A. (2013). Long-term Aerobic Exercise Is Associated With Greater Muscle Strength Throughout the Life Span. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 68(6), 631-638.
• Harber, M. P., Konopka, A. R., Douglass, M. D., Minchev, K., Kaminsky, L. A., Trappe, T. A., & Trappe, S. (2009). Aerobic exercise training improves whole muscle and single myofiber size and function in older women. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 297(5), R1452-R1459.
• Ozaki, H., Loenneke, J. P., Thiebaud, R. S., Stager, J. M., & Abe, T. (2013). Possibility of leg muscle hypertrophy by ambulation in older adults: a brief review. Clinical interventions in aging, 8, 369.
• Rosenkilde, M., Reichkendler, M. H., Auerbach, P., Bonne, T. C., Sjödin, A., Ploug, T., & Stallknecht, B. M. (2014). Changes in peak fat oxidation in response to different doses of endurance training. Scandinavian Journal of Medicine & Science in Sports.

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.