Thank you Adrian for responding and in great detail. I completely agree with you but would take this a little step further in saying that for whatever negative health implications e's, msg (which i'm not convinced on though) and other additives, i place sugar as the number 1 most significant factor and if i had to pull a number out i would claim around 90-95%. Why? Because having removed sugars and ALL carbohydrates for the week, i have noticed and felt exactly what you describe in your daily life (feeling refreshed, sleeping well, full of energy and the inner need to want to burn it off because your hyper as a result, feeling as if your actually over consuming on foods, etc.). I feel exactly like that as of removing all carbs and relying in fat, protein and very low to non existent carbs in very green veggies (which i've been plastering with butter for flavour ). I can honestly say that i have never felt so good in my entire freaking life. Regarding the heart beat, i can completely understand your advise to build up to it as i've not been exercising at all. But here's the thing, when i did that on day 5 or 6 (can't remember now) i wasn't trying to get it up to 175. I was just doing exercises and without forcing myself to work hard but was able to do more of them and hold strenuous positions for way longer than before the test period. It didn't feel like effort, it felt effortless in fact and so i did a total of 15 minutes instead of the usual 5-10 minutes i could only do in the past and would then pass out. I use to be able to go no higher than 120-140. It was completely unexpected that after the 15 minute workout on day 5 or 6, afterwards testing my heart beat, that the reading came out at 175 bpm. I was in complete shock, not only by the fact in was so high but also that the work out felt effortless and i was completely not tired after doing it. Now i understand (as an engineer) that a sample of 1 (just me in this test) doesn't prove anything (it requires many more to show a correlation and then to go deeper and prove causation to make a statement of causal inference and/or scientific fact). But it strongly suggests to me that physical endurance and fitness goes way beyond physical training for stamina (not that i'm saying stamina training say for marathon running does not work and is not important, not at all). For me to achieve those results and the only thing that had changed was the complete absence of carbs and substituting it with more fat (which fat then made up around 50-70% of my caloric food intake per day) i felt more energised, clear headed (something that was most obvious to me as my awareness heightened like giving someone an adrenaline shot into the heart), and naturally much fitter (just based on the 175bpm that was effortless to achieve compared to my 120-140 in the past that left me very fatigued and in only 5-10 minutes). The weight loss part is based on the sound research science that Dr Lustig performed, the fitness part not so much but my personal observations are showing clear correlations (which i can't prove is due to the zero carb and increase fat diet test) but it's the only causal link i can see or think of since i was so careful to avoid other variables affecting the results from before to after. It's day 7 by the way guys and i have not lost 5kg! Wooohoooo! And it was freaking effortless!!!! I'm so pumped of energy i've been struggling to get to sleep a little so tonight i'm heading to the gym, not because of will power but because my wanted naturally desires to do something active. It doesn't feel like a chore but a reward to go do it! I used to hear the notions of 70:30 diet:exercise, or someone else would argue it's 60:40 or 80:20 or whatever but now i know the truth. It's 100:0...as in 100% diet. Why? Because with the correct diet, you don't need to exercise to lose weight (if i've proven/confirmed anything from Dr Lustigs research it is unequivocally this imo) but when it comes to exercise and being active during the day, this is govern entirely by what you eat. You eat the right foods and your body responds by raising your metabolism sky high making you feel great throughtout the day feeling energised. As a result, you feel this inner need to expel it and hence forth exercising naturally comes on it on without the need of conscious will power. We need to change the slogan of "You are what you eat" to "You are what you eat and you do because of what you eat."