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Why We Get Fat

sciencebasedmedicine.org

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Re: Why We Get Fat

#71

Post by robbiep »

Mz wrote: post #70
robbiep wrote: post #68

Earlier quoted context omitted.

I think you mean carbon instead of oxygen, and it's 2 at a time, not one at a time. Your analogy is roughly correct but in the base, reductionist biochemistry of which the body functions, you have fats (chains of carbons with hydrogens on them - directly burned this way), carbs (basic form C6H12O6) which are also directly burnt this way with water coming off, and protein, which has occasional nitrogen atoms and some…

You know, I feel really crappy today. I am not finding anything that readily matches my recollection of the process, though glycolysis and atp come up in my search and that partially matches my memory. Maybe you could link me to something that fairly clearly shows what you mean? My understanding is "burn" = "consume oxygen". Thanks.

burning is oxidation, and oxidation requires O2 (although it doesn't always require O2 -oxidation chemically speaking is stripping Electrons and Hydrogen atoms out of a molecule. Which liberates energy.

So you are right. My take on your comment was that you had confused Carbon and oxygen... Since Carbon is the fuel and Oxygen is the oxidising agent , and the convention is basically to talk about the fuel as the one that is being consumed.

I don't have any videos or anything but if you are interested I have attached a link to my old biochemistry notes which, especially if you have a rusty background in anything resembling science, should hopefully jump you along a bit

http://sdrv.ms/SHJQHs

Re: Why We Get Fat

#72

Post by Mz »

robbiep wrote: post #71
Mz wrote: post #70

Earlier quoted context omitted.

You know, I feel really crappy today. I am not finding anything that readily matches my recollection of the process, though glycolysis and atp come up in my search and that partially matches my memory. Maybe you could link me to something that fairly clearly shows what you mean? My understanding is "burn" = "consume oxygen". Thanks.

burning is oxidation, and oxidation requires O2 (although it doesn't always require O2 -oxidation chemically speaking is stripping Electrons and Hydrogen atoms out of a molecule. Which liberates energy. So you are right. My take on your comment was that you had confused Carbon and oxygen... Since Carbon is the fuel and Oxygen is the oxidising agent , and the convention is basically to talk about the fuel as the one t…

Thanks. I will try to look for something some other time to clarify my understanding. Some time when I feel less crappy.

Re: Why We Get Fat

#73

Post by glenra »

spindritf wrote: post #48
travisp wrote: post #17

Earlier quoted context omitted.

>At the end of the day, everything boils down to "eat fewer calories than you expend". Sure, if you stop eating you will lose some weight, but, you can die of starvation while obese. In animal studies, that Taubes cites in one of his books, it is possible to reduce calories and the animals won't lose weight and it is also possible to add a lot of extra calories and not become obese. Calories have something to do with…

> Sure, if you stop eating you will lose some weight, but, you can die of starvation while obese. This guy[1] went for over a year on vitamins and water. He didn't die, and he did drop a lot of weight. Actually, "prolonged fasting in this patient had no ill-effects." Though it's probably one of those things you really shouldn't try at home. [1] http://pmj.bmj.com/content/49/569/203.abstract

Taubes gives the example of rats bred or genetically modified to be fat - if you starve them, the body eats the heart and the brain before it gives up on the fat - the animal can starve to death while still fat. Getting fat changes you - a person who was 400 lbs and diets down to 200 has a very different metabolism than a person who has always been 200 lbs. It's possible that something we've been doing is making fat more prone to stick around than it was in times past.

The hypothesis that the problem is too many carbs is plausible but not proven and the full truth is certainly going to be more complex.

Starvation guy is an interesting data point in any cace.

Re: Why We Get Fat

#75

Post by super_mario »

spindritf wrote: post #44
super_mario wrote: post #14

I challenge the author to load himself on steak and saturated fats and no carbs and come race me 100 miles on a road bike. I burn in excess of 4000 Calories on a 80 mile bike ride. That's a kilogram of rice on a single ride. And honestly I find it incredibly hard to eat enough just to satisfy the energy requirements of racing. Not eating carbs and attempting an endurance race event is just suicidal and guaranteed way…

> come race me 100 miles on a road bike Because that's exactly what people do every day and what they should always be prepared for. I keep my racing bike and a bag of rice right next to the emergency kit. Some people are into thousands of miles on a bike, or marathons, great for you, but most aren't. And, beyond enjoyment, there's no reason to be into that, there are better, cheaper and less time-consuming ways to m…

I'm not too worried about coronary disease, but I am concerned about my brain, my mental well being, Alzheimer's, cognitive ability, depression etc, esp. considering everyone on this site is at a higher risk for all of these due mostly to the stress of the profession and sedentary lifestyle.

Unfortunately, leg rises, push ups, pull ups etc (strength and resistance training in general) do nothing for your brain. On the other hand brain thrives on aerobic activity, esp. higher end of the spectrum near the aerobic threshold. And this is also great for your mood and general well being.

It also takes a decade to develop your aerobic engine (well there are really 3 - 4 metabolic systems available to you when you do aerobic exercise, but some are so short in duration that are negligible and the others respond to training very well). Developing power at threshold (i.e. put out as much power as you can at a level just at the edge between aerobic and anaerobic) is the slowest to develop.

For more on connection between brain health and aerobic exercise see Dr. Medina's Google talk on his "Brain Rules". It's quite enlightening in general

http://youtu.be/IK1nMQq67VI

Re: Why We Get Fat

#76

Post by legitsource »

anthonyb wrote: post #51
funkwyrm wrote: post #41

The big mistake begins here: "Simple physics requires that to lose weight, we must burn more calories than we ingest" THAT fallacy is how the author leads the reader in to HIS strawman argument, that somehow Taubes is unaware of, or disregards, the laws of thermodynamics. 1) Ingesting calories is not relevant, digesting is. 2) We don't "burn" any calories whatsoever. We use various components of food as raw materials…

He's also completely overlooking the overfeeding studies that Taubes references in his books. Eating 10000 calories of cheese or pork chops is a lot harder than with ice cream.

It's easy to eat a stick of butter and a cup of sugar in the form of frosting.

It's really hard to eat the equivalent calories in butter alone.

Re: Why We Get Fat

#77

Post by rb2k_ »

lambda wrote: post #12
rb2k_ wrote: post #4

While this is highly non scientific and very subjective, my personal experience is pretty much exactly mirroring the article. A high-fat, low-carb diet makes it easy to lose weight and and fat at the same time. While running/pullups/... help with muscle definition and make me feel healthy in general, the weight loss for me seems to be 80% related to the food I eat. Here are the graphs: http://i.imgur.com/y0CJJ.png I…

I fell like there's an awful lot of confirmation bias in people's reports of how well low-carb diets work, just like there was back when low-fat diets were the big fad. In general, any deliberate change in your diet is likely to lead to results, at least in the short term, as you're paying that much more attention to what you're eating. This is similar to the strength of the placebo effect in medical studies; one rea…

> In general, any deliberate change in your diet is likely to lead to results, at least in the short term, as you're paying that much more attention to what you're eating.

The graphs in my original post were over the course of a year

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