Archive for February, 2016
When readers first linked to the “paleo diet makes you fat!” study in comments, I replied that I generally dismiss mouse and rat studies as irrelevant to humans, except in certain circumstances. I should probably talk about those circumstances.
But first, I’ll explain which studies I dismiss outright: pretty much all diet studies that involve rodents. We’re not rodents. The foods that have negative effects on rodents may have positive effects on humans and vice versa.
The big cholesterol scare started more than 100 years ago when scientists fed cholesterol to rabbits, who rapidly developed heart disease as a result. Oh my gosh, cholesterol must cause heart disease in humans!
Stupid conclusion. Rabbits are herbivores. They don’t eat cholesterol. There’s no reason they should have the biological machinery to deal with cholesterol. So – duh! – it builds up in their systems and causes problems. I’m pretty sure if we fed lions an all-vegetarian rabbit diet, they’d become quite ill. But that doesn’t mean carrots are bad for rabbits or humans. It simply means lions are obligate carnivores.
So even if researchers fed rats and mice a true paleo diet of meats and vegetables, I still wouldn’t give a rat’s ass (pardon the pun) about the results — positive or negative – because there’s simply no reason to assume those results translate to humans. We’re not rats. The diet that’s perfect for them is very unlike the diet that’s perfect for us. The researchers in the dumbass “paleo diet makes you fat!” study mentioned that standard rat chow is 3% fat. Has there ever been a group of paleo humans who lived on a 3% fat diet? I sincerely doubt it. Rats are probably biologically geared to thrive on an extremely low-fat diet. We’re not.
But of course, researchers in these studies rarely feed mice and rats anything like the human diet they’re supposedly testing. The “paleo” diet in the dumbass study consisted largely of isolated casein, sugar and canola oil. It was nothing like a paleo diet. The study has absolutely zero relevance to humans eating an actual paleo diet.
This little sleight-of-hand seems to be a habit among some researchers. More than once, I’ve dug into a mouse or rat study of the “Atkins” (ahem-ahem) diet and found that the primary fats were Crisco or corn oil, and the sole source of protein was casein … you know, just like Dr. Atkins recommended. Then when the rats or mice became fat or sick, dingbats in the media dutifully reported that New Study Show Atkins Diet Causes (insert scary result here)!!
So when should we pay attention to rodent studies? Well, I’ll least give them a look if they test the result of drugs or hormones. In the animal kingdom, hormones are the chemical messengers that trigger the code written into our biological software. Hormones have been around since before humans existed. I think we can safely assume hormones produce similar effects in a man and a mouse.
So if researchers pump male mice full of testosterone and those mice become leaner, stronger, and start throwing punches in bars at the slightest provocation, I’d expect to see similar effects in male humans. If researchers inject rats with high doses of insulin and the rats start eating like crazy and getting fat, I’d expect a similar result in humans. But I’d still take those studies with a grain of salt.
Here’s the type of rodent study I don’t take with a grain of salt: those that disprove a supposed Immutable Law of The Universe. Back in 2011, I wrote about a study in which researchers calculated how much food mice were eating ad libitum. Then they took one group of mice and cut their daily calories by just 5%. Here are some quotes from my post:
Now, according to Jillian Michaels and the other leading experts in thermodynamics, there are only a couple of possible outcomes for these experiments:
- The calorie-restricted mice, who were prevented from making little pig-mice of themselves, ended up weighing less and were leaner.
- If the calorie-restricted mice somehow ended up fatter, it could only be because they were far less active than the mice who ate freely.
Yup … if you get fat, by gosh, it means you’re either eating more or moving less. Now let’s look at the actual results:
At the end of the second experiment (three weeks), the average weight for both groups was virtually identical — it was also virtually identical to their baseline weights. But the calorie-restricted mice had 43.6% more fat mass and 6.4% less lean mass than the free-eating control mice.
Ah, well then, the mice who gained fat mass must’ve been less active, right?
Nope. According to the study data, there was no difference in locomotor activity levels between the two groups.
The calorie-restricted mice ate less, they moved around just as much, but they ended up weighing the same as the mice allowed to eat freely, and also ended up with more fat and less muscle. Oh, dear me … did these mice find a way to violate the laws of thermodynamics?
I paid attention to that study because the calorie freaks insist that according to the laws of physics, if you eat less and move around just as much YOU MUST BURN FAT FOR FUEL AND LOSE WEIGHT. IT’S AN IMMUTABLE LAW OF THE UNIVERSE. But these mice ate less, moved around just as much, and gained fat mass while losing muscle.
Yeah, it’s just a mouse study, but the laws of physics are the laws of physics, period. They don’t apply to humans and then go on vacation when mice saunter into the room. So if the laws of physics say eating less while remaining active must always lead to fat loss, that would apply to both large and small furry creatures.
No, those mice didn’t violate the laws of physics. And no, the experiment didn’t disprove any laws of physics. But it did disprove the calorie-freak argument that cutting calories while remaining just as active MUST ALWAYS LEAD TO BURNING AWAY BODY FAT BECAUSE THE LAWS OF PHYSICS SAY SO.
The laws of physics say no such thing. They merely say that if you lose weight, you burned more calories than you consumed. These mice – despite remaining just as active – slowed down their metabolisms and burned muscle tissue for fuel in order to get fatter. It was probably a programmed reaction to what their little mouse bodies interpreted as a risk of starvation. No laws of physics were harmed in the process.
So here’s the one part of the “paleo diet makes you fat!” study I found relevant:
After 3 weeks, mice fed the LCHFD began to diverge from the chow-fed group, and at 5 weeks the difference in body weight was statistically significant. At the end of the study, white adipose tissue mass was also significantly increased. The LCHFD has a higher energy density than the chow diet (24 vs 13.5 MJ kg−1); however, the increased body weight of mice fed the LCHFD was not associated with a higher energy intake.
Yup, the mice fed the full-of-crap “paleo” diet (which tripled their sugar intake) gained more weight and more body fat. We can’t blame it on palatability, because they didn’t say, “Oooh, this is yummy!” and eat more. We can’t blame it on consuming too many calories, because they didn’t consume more calories. So if the researchers kept accurate records on food consumption (and it appears they did), we have a situation where mice eating a crap diet got fatter than their control-group cousins, despite not eating more.
That’s a relevant result, even though it’s a mouse study. It disproves the dearly-held belief among the calorie freaks that getting fatter is always and forever the result of eating too many calories BECAUSE THE LAWS OF PHYSICS SAY SO. And it lends credence to the belief that food quality affects how calories are partitioned, burned and stored. Different foods send different commands to the biological software. That’s the only useful lesson from an otherwise garbage study.
And once again, no laws of physics were harmed in the process.
Of mice and men. Again.
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I saw the scary headlines a couple of days ago. You probably did too. The one that caught my attention was this:
Diabetes expert warns paleo diet is dangerous and increases weight gain
That headline was over an article on the EurekaAlert! website. Here are the opening paragraphs:
A new study has revealed following a low-carbohydrate, high-fat diet for just eight weeks can lead to rapid weight gain and health complications.
The surprise finding, detailed in a paper in Nature journal Nutrition and Diabetes, has prompted University of Melbourne researchers to issue a warning about putting faith in so-called fad diets with little or no scientific evidence.
Goodness, no, we wouldn’t want to make our dietary decisions based on little or no scientific evidence. Luckily for us, someone conducted a rigorous and relevant scientific study before declaring the paleo diet dangerous for humans. That’s why it made such a splash in the news.
Here are some paragraphs from another article that appeared in Medical News Today online:
Scientists have warned against following celebrities into “fad” diets that are not supported by scientific evidence, as findings published in the journal Nutrition and Diabetes reveal that just 8 weeks on the “Paleo” diet can pile on the pounds and raise the risk of health problems.
Adherents of the LCHF diet consume more protein, fiber and fat than the average Western diet and less sugar and starchy carbohydrates.
Suggested “dos” include grass-produced meats, fish or seafood, fresh fruits and vegetables, eggs, nuts and seeds, and healthful oils such as olive, walnut, flaxseed, macadamia, avocado and coconut.
Foods to avoid include cereal grains, legumes – including peanuts – dairy products, refined sugar, potatoes, processed foods, salt and refined vegetable oils.
So apparently, those rigorous and concerned scientists fed people more protein, more fat, and less sugar than a standard diet and were surprised when the paleo dieters experienced rapid weight gain and health complications in just eight weeks.
Damn, that is worrisome. To think I’ve been operating under the assumption that a diet of grass-produced meats, fish or seafood, fresh fruits and vegetables, eggs, nuts and seeds, and healthful oils such as olive, walnut, flaxseed, macadamia, avocado and coconut would be good for me. I was so very, very disappointed to learn than people who spent eight weeks living on grass-produced meats, fish or seafood, fresh fruits and vegetables, eggs, nuts and seeds, and healthful oils such as olive, walnut, flaxseed, macadamia, avocado and coconut got fat and sick.
But since I’m not an idiot, I kept reading. Here are more quotes from the Medical News Today article:
Researchers at the University of Melbourne were concerned about the hazards of a paleo diet, especially for those who are already overweight and living a sedentary lifestyle and for individuals with pre-diabetes or diabetes.
To investigate, they took two groups of overweight mice with symptoms of pre-diabetes.
The mice in one group consumed an LCHF diet for 8 weeks, 60% of which was fat, compared with their usual 3% fat intake. Carbohydrates made up 20%. The mice in the control group ate their usual food.
After 8 weeks, the Paleo diet group had increased in weight, glucose intolerance and insulin. The mice had gained 15% of their body weight, and their fat mass had doubled from 2% to almost 4%.
This “extreme weight gain” is equivalent to a person who weighs 200 pounds gaining 30 pounds in 2 months.
Wowzers. So if you switch to a diet of grass-produced meats, fish or seafood, fresh fruits and vegetables, eggs, nuts and seeds, and healthful oils such as olive, walnut, flaxseed, macadamia, avocado and coconut, you could gain 30 pounds in just two months – if you’re a mouse.
Then again, I’ve seen headlines before about mouse studies that supposedly demonstrated the hazards of a paleo or LCHF diet. The scientists never seem to feed those mice grass-produced meats, fish or seafood, fresh fruits and vegetables, eggs, nuts and seeds, and healthful oils such as olive, walnut, flaxseed, macadamia, avocado and coconut.
So I took a peek at the full study. Let’s see what the researchers themselves have to say:
NZO mice were maintained on either standard rodent chow or an LCHFD from 6 to 15 weeks of age.
What the heck is an NZO mouse? Yeah, I wondered that myself. So I looked it up on the website for a company that supplies them:
NZO mice of both sexes exhibit high birth weights and are significantly heavier at weaning age. Severe obesity (including both visceral and subcuatneous fat depots) develops even when mice are maintained on a standard diet containing 4.5% fat.
I see. So we’re talking about mice bred to become obese, even on a low-fat diet.
Both males and females of the NZO/Hl substrain exhibit impaired glucose tolerance (IGT), but subsequent type 2 maturity onset (NIDDM) diabetes development is limited to males, with a phenotype penetrance of 50% or less. NZO/Hl mice also show anti-insulin receptor antibodies, a defect in leptin transport, and hypertension.
Wow, sounds just like me. In fact – amusing story here – I used to wonder why my parents, who were struggling financially when The Older Brother was born, decided to add the expense of a second child a mere 18 months later. I always assumed it was because they were Catholic and that’s what the rhythm method accomplishes: it makes more Catholics.
Eventually, I dared to asked my mom why they had me so soon after my brother. Her reply was something like, “We were very interested in biology and wanted to produce a son who would become severely obese on a standard diet and show impaired glucose tolerance, anti-insulin receptor antibodies, a defect in leptin transport, and hypertension. That was you.”
So I’m totally on board with the idea of applying the results of an NZO mouse study to me. Still, I can’t help but wonder about that diet. Let’s go back to the study:
Prior to the study, all mice were fed a standard rodent maintenance diet. At 6 weeks of age, mice were either transferred to an LCHFD or maintained on the standard diet (chow) for a further 9 weeks. The LCHFD contained 24 MJ kg−1 digestible energy (3.1 MJ or 13% coming from protein, 1.5 MJ or 6% from carbohydrate and 19.5 MJ or 81% from fat. The chow diet contained 13.5 MJ kg−1 digestible energy, with 2.7 MJ or 20% coming from protein, 9.5 MJ or 70% from carbohydrate and 1.4 MJ or 10% from fat.
I see. The standard-chow mice got a diet of 20% protein, while the “paleo” mice got a diet of 13% protein. Wait a minute … how did the Medical News Today article describe a paleo diet again? Let me go find that quote again … okay, here it is:
Adherents of the LCHF diet consume more protein, fiber and fat than the average Western diet and less sugar and starchy carbohydrates.
So the “paleo” mice consumed 35% less protein than the control group. And according to the study documents, the protein the “paleo” mice consumed consisted entirely of casein. Let’s look up the definition of that word.
A protein precipitated from milk, as by rennet, and forming the basis of cheese and certain plastics.
Yup, this is sounding more and more like a true representation of the paleo diet. That’s what most paleo dieters I know do: they precipitate milk as by rennet to isolate the casein and then eat it.
Well, at least the mouse “paleo” diet was high in fat – perhaps ridiculously high in fat, but high in fat. And I’m sure they were paleo fats. After all, as the Medical News Today article clearly stated, paleo dieters avoid cereal grains, legumes, dairy products, refined sugar, potatoes, processed foods, salt and refined vegetable oils.
So I looked up the contents of the “paleo” diet. As a percent of the total, the “paleo” mice got 54% of calories from cocoa butter, 14% from clarified butter, and 14% from canola oil.
Dangit! That is EXACTLY LIKE MY PALEO DIET! I get up every morning and swallow big globs of cocoa butter, then wash it down with clarified butter and canola oil … because it’s not as if butter (or casein) is a dairy product and canola oil is a refined vegetable oil or anything. I take my paleo seriously.
I kept reading to make sure the relative increase in fat intake for the mice was similar to the relative increase in fat for humans who switch to a LCHF diet. Here’s what the study had to say:
Rodent chow is normally low in fat (3% of energy) and high in carbohydrates (approximately 50% starch). In contrast, the LCHFD used here had a very low carbohydrate (only 6% of energy, 100% sucrose) and high fat content (81% of energy).
Just as I feared: the change is totally relevant to humans going LCHF. Compared to their normal diet, the “paleo” mice increased their fat intake by 2567%. Same here. When I switched from low-fat to paleo, the percent of fat in my diet went from 20% to 513% of total calories. I had no idea that would be bad for me — especially the canola oil.
The carb content of the “paleo” diet was low, of course. And since paleo is what it is, those carbs probably came from vegetables, maybe some tubers …
The carbohydrate content of the LCHFD was exclusively derived from simple sugar.
Wait a minute … the paleo mice got 6% of their calories (100% of the carb calories) from simple sugar? Well, I’m sure that was at least a reduction compared to the standard chow.
Typically, rodent chow carbohydrate is contributed to by 50% starch and approximately 2% simple sugars.
I see. So the non-paleo mice got 2% of their calories from simple sugars, and the “paleo” mice got 6% of their calories from simple sugars. Well, once again, that’s exactly what happens when people go on a paleo diet: they triple their intake of simple sugars. That’s why the Medical News Today article mentioned this:
Foods to avoid include cereal grains, legumes – including peanuts – dairy products, refined sugar, potatoes, processed foods, salt and refined vegetable oils.
So there you have it. Mice and men. People who try paleo diets are almost exactly like NZO mice, and the paleo diets they try are almost exactly like the “paleo” diet in this study. So if you go paleo, you’re probably going to get fat and sick. I know it’s true, because the lead researcher said so:
Lead author, Associate Prof Sof Andrikopoulos says this type of diet, exemplified in many forms of the popular Paleo diet, is not recommended – particularly for people who are already overweight and lead sedentary lifestyles.
“Low-carbohydrate, high-fat diets are becoming more popular, but there is no scientific evidence that these diets work. In fact, if you put an inactive individual on this type of diet, the chances are that person will gain weight,” Andrikopoulos, President of the Australian Diabetes Society, said.
Yup, the lead researcher is President of the Australian Diabetes Society, which (like our own Diabetes Society) has been pushing low-fat diets for years. But I’m sure that didn’t affect how he designed or interpreted the study.
And neither did the fact that (according to his bio) he’s received a lot of research money from drug companies. I mean, It’s not as if the paleo diet would reduce the need for drugs or anything.
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Random stuff not worthy of a full post:
The Garmin Forerunner
Awhile back, I mentioned that I had to send back my FitBit because the heart monitor was way off. I went with a Garmin Forerunner instead. A reader emailed this week to ask if I like the Forerunner, since I never mentioned it again.
Yes, I do like it. I’ve compared the heart-rate reading to a manual reading several times, both before and during workouts. It’s always spot-on. I also like how I can press one of the buttons a few times and see my heart rate for a moment without leaving the watch mode. So I guess it’s a case of getting what you pay for. The FitBit was cheaper, but not up to snuff.
My plan was to monitor my heart rate during aerobic sessions on the bike. I’ve been using the bike to do sprints a few mornings per week, but haven’t had much time to do those longer aerobic sessions because …
Tighter schedule – yeah, I like I needed that
For a few years, programmers at the contracting job were encourage to share a cubicle. Half the week at home, half in the office. I worked at home Mondays, Tuesdays and Wednesday mornings. It was great. No commute time at all for the firs two days of the week. I’d sleep until 8:00, wake up slowly with a cup of coffee, work until 5:30 or so, then turn my attention to the book. On Wednesdays, I’d put in a few hours at home, then stop at the gym for my workout on the way to the office.
Ahhh, the good old days. They’re gone. Someone high up the totem pole decided earlier this year that programmers need to work in the office every day. Why? Yeah, we asked that too. The only explanation I heard is that a few people abused the work-at-home days — as in not really working much at home.
Now, if I were in management, I’d handle that problem by requiring the bad apples to work in the office every day and let those who didn’t abuse the system continue spending half the week at home. But I’m not in management. So now I’ve got the long commute five days per week. I’m up early every day so I can be at my desk by 9:30. I’m up earlier if I want to squeeze in a workout at the gym. No more waking up slowly with the big cup of coffee.
It’s pointless to leave downtown Nashville at 5:30 PM. That just means sitting in rush-hour traffic. So now I put in my programming time, eat a quick dinner, then stay at the office for another couple of hours to write. It’s the only way I’ll get the book done on schedule. It’s also affected my eating habits …
Chareva’s every bit as busy as I am. Chickens, dogs, the cat, the girls with their gymnastics classes and school activities … all those mommy chores add up. Meanwhile, she’s working through tutorials on InDesign so she can lay out the book. Oh, and there are all those cartoons and graphics yet to produce.
Once I had to start working downtown every weekday, I told her to forget about making me a lunch and a dinner to pack every day. She doesn’t need the extra workload. So I started taking – egads! – packaged food to the office for dinner some days.
I’m a big believer in not letting perfect become the enemy of good. There are no perfect meals-to-go in grocery stores, at least not that I can find. But I found that many of the Atkins dinners are at least good. They are (duh) low in carbs and reasonably high in protein. A lot of the other “diet” meals out there consist of pasta, a bit of protein, and a bit of fat.
When I check the ingredients for higher-protein meals from most other brands, textured soy protein always seems to be high on the list. The Atkins dinners at least use meat instead of meat substitutes. There are bits of other ingredients in there you wouldn’t use at home (what the heck is corn protein, anyway?) but overall, I think I can eat these things without trashing my body. That’s the hope, anyway.
My main complaint — with all brands — is the portion size. They actually brag on the boxes, Only 330 calories! To which I’d reply, What adult male is going to be satisfied with a 330-calorie dinner?! So I always end up eating two of them.
The dinners aren’t real-food perfect, but I found a real-food snack bar that doesn’t have soy protein, or corn protein, or any other fake-food nonsense. Well, I didn’t find it. It found me. The owner of Nutty Crunch bars (who is also personal trainer and fitness buff) sent an assortment for the family to try.
I liked them. Chareva liked them. The girls liked them. The bars are crunchy and tasty. They’re low in carbs too, despite a bit of sweet taste. Here’s the list of ingredients, which varies only slightly among the different flavors:
Coconut chips, almonds, pecans, walnuts, cashews, sunflower seeds, pumpkin seeds, organic coconut oil, organic raw honey, egg whites, organic molasses, Celtic sea salt, Madagascar vanilla or cinnamon.
That’s it. No chemical names. There are seven carbs in a bar, but three of those are fiber. Six grams of protein as an added bonus.
I’m not in business with the guy or anything. I don’t make advertising or profit-sharing deals for any of the products I mention on the blog. So if I say I like something, it’s because I like it and think it’s worth sharing.
A quote about doctors
A reader emailed to share some quotes from a 1988 book titled What Every Engineer Should Know About Artificial Intelligence. The first quote is from a chapter on expert systems:
Rule-based expert systems are purely empirical in that the expert system knows nothing of any underlying causality. Rules encode experiential observations, such as “This disease is associated with fever,” “That disease is accompanied by certain chemicals in the urine,” or “Watch hydraulic pressure for a few hours after the pump is adjusted,” without including any information about why these rules work. Such systems are called “shallow systems” and are said to use “shallow reasoning.” Rule-based expert systems are common in medicine because doctors are not taught much about disease mechanisms.
Right. They’re taught which drugs to prescribe when the body breaks down, not how to prevent it from breaking down. The second quote is a footnote to the first:
There is so much purely diagnostic information taught in medical school that there is little time to explain the underlying mechanisms of disease. Doctors seem not to need to know much about the causes of disease to make successful diagnoses; tracking down causes is left for epidemiologists. Medical school has been described as a place where students learn correlations and ignore causation. A student may be taught to treat gall bladder cancer with a certain drug. They are not taught that the drug is a metabolic poison that damages rapidly growing cancer cells more than it harms normal cells. This explains side effects such as hair loss because hair cells grow rapidly, but there are so many rules to learn that there is no time for such deeper details. Medical training is based on memorization of shallow rules.
Couldn’t have said it better myself.
I believe the rush-hour traffic has subsided. Time to make that commute home – just like on every other friggin’ weekday now.
I sure hope that book sells a million copies. Then I’ll only commute the kitchen and back.
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A link in comments reminded me of a criticism of Good Calories, Bad Calories I see now and then. In a nutshell, the criticism goes like this:
Taubes says people get fat because insulin makes their fat cells release fatty acids too slowly, so they have to eat more to avoid cellular starvation, and then they get fat. But studies show fat people have the same concentration of fatty acids in their bloodstreams as lean people. So there. That proves Taubes is wrong.
Uh, no. The fact that fat people have a steady supply of fatty acids in their blood doesn’t prove him wrong at all. The people who think it does either didn’t actually read Good Calories, Bad Calories or didn’t grasp one of the key concepts.
Let’s start with an analogy. Suppose we’re studying people on a planet where it’s considered disgusting to have a large savings account. And yet many people do. I want to understand why, so I spend years digging through financial research. Then I offer this explanation:
For half of each year, people on this planet have no regular income and have to live off the interest from their savings accounts. Most accounts pay 10% interest, so most people continuing saving until the 10% interest provides enough cash to pay their bills.
However, because of a banking flaw, some people’s accounts pay less than 10%. At the lower rate, the interest they can withdraw isn’t enough to pay their bills – that is, unless they compensate by making bigger deposits to build up more savings. So they do. Each time the interest rate drops a bit, they deposit and save more until the interest is once again enough to pay their bills. For people whose accounts pay a low interest rate, this requires a BIG savings account.
With me so far? Great. Now suppose another researcher digs up a study showing that people with fat savings accounts withdraw the same amount of cash each month as people with normal savings accounts. Waving that study around, the researcher makes this announcement:
Aha! Naughton is clearly wrong! He claims people grow fat saving accounts because they can’t withdraw enough cash as interest. But now we know people with fat accounts are withdrawing just as much cash as everyone else. So he’s wrong. Wrong, wrong, wrong!
You see the flaw in that conclusion, right? The fact that the fat-account people are withdrawing enough cash to pay their bills doesn’t prove my explanation is wrong – because I never claimed they don’t end up withdrawing as much cash as everyone else. I said they maintain big accounts so that they can withdraw as much cash as everyone else. The researcher didn’t read or didn’t understand my explanation of how these people solved the defect with their low-interest accounts. He apparently stopped reading after the description of the defect itself.
Let’s return to our own planet. Here’s my quick, user-friendly summary of some lengthy passages in Good Calories, Bad Calories.
To keep your blood sugar in the normal range, your body needs to alternately store and release fatty acids. When glucose goes up, your body brings it down by storing fatty acids and burning glucose as the primary fuel. But as glucose continues to drop, your body prevents it from dropping too low by releasing fatty acids for fuel. As most of your body switches to burning fat, glucose is preserved for the brain – which requires at least some glucose every minute of every day.
If you can’t release a sufficient supply of fatty acids, you have a problem. When glucose drops after meals (not to mention during the long night’s sleep), your body will experience a fuel shortage. You’ll be hungry. Your brain may sense a threat to the consistent fuel supply it needs. If this is a regular experience, it’s a problem your body must and will work to fix.
That’s the quick summary. Now here are some paragraphs from what I consider the most important section of the book, offering an explanation of how our bodies fix the problem (bold emphasis mine):
If energy goes into the fat tissue faster than it comes out, the energy stored in the fat tissue has to increase. Any metabolic phenomenon that slows down the release of fat from the fat tissue – that retards the “energy out” variable of the equation – will have this effect, as long as the rate at which fat enters the adipose tissue (the energy in) remains unchanged, or at least does not decrease by an equal or greater amount.
Pennington suggested that as the adipose tissue accumulates fat, its expansion will increase the rate at which fat calories are released back into the bloodstream (just as inflating a balloon will increase air pressure inside the balloon and the rate at which air is expelled out of the balloon if the air is allowed to escape), and this could compensate for the initial defect itself. We will continue to accumulate fat – and so continue to be in positive energy balance – until we reach a new equilibrium and the flow of fat calories out of the adipose tissue once again matches the flow of calories in.
By Pennington’s logic, obesity is simply the body’s way of compensating for a defect in the storage and metabolism of fat. The compensation, he said, occurs homeostatically, without any conscious intervention. It works by a negative feedback loop. By expanding with fat, the adipose tissue “provides for a more effective release of fat for the energy needs of the body.” Meanwhile, conditions at the cellular level remain constant; the cells and tissues continue to function normally, and they do so even if we have to become obese to make this happen.
So to sum up:
According to Taubes, if our fat cells begin releasing fatty acids more slowly, we get fatter to overcome this defect. Once we’re fat enough to release a sufficient supply of fatty acids, our weight tends to stabilize again. We’re back in a state of energy balance. We now store and release fatty acids as needed, just like thin people – but we had to get fatter in order to do so. If the fat cells slow their rate of release again, we become fatter again to compensate. That’s how our bodies stay in a state of energy balance.
Nothing in that explanation says obese people release fewer fatty acids into their bloodstreams than thin people. It says they achieve a normal supply of fatty acids by being fatter. That’s why (according to the book) our bodies fight to gain and keep the fat – because if we can’t release enough fatty acids between meals, we can’t keep our cells fed and our glucose levels stable. To shed body fat without fighting our own bodies, we first have to fix the root of the problem. (That’s where the change in diet comes in.) Once we can release enough fatty acids with a smaller fat mass — because the rate of release speeds up again — our bodies will be willing to lose the extra fat.
Again, I consider that one of the crucial ideas – perhaps the most important idea – in the entire book. I don’t know how anyone could miss it. But apparently plenty of people did.
During between-session chit-chat at a conference some years ago, a blogger whose name I won’t mention tossed out the line about how fat people have just as many fatty acids in their bloodstreams as thin people, so Taubes is wrong and therefore the insulin hypothesis is wrong.
“Well, actually Taubes wrote that each time our fat cells become a little slower at releasing fatty acids, we get a little fatter to compensate,” I replied. “Fat people release as many fatty acids into their bloodstreams as thinner people, but they need more fat mass to do so. That’s why they’re fat. Being fat keeps them in a state of energy balance.”
That drew a look of confusion from the blogger, who then replied, “Hmm, I don’t remember that part of the book.”
I didn’t say anything, but I was thinking, YOU DON’T REMEMBER THAT PART OF THE BOOK?! Are you @#$%ing kidding me? That’s like reading Huckleberry Finn and not remembering the part about the runaway slave.
Don’t get me wrong here. I don’t have a problem with people disagreeing with Taubes, challenging the insulin hypothesis, offering their evidence to counter his, whatever. That’s how it should be. Real science is not (despite what some politicians believe) about reaching a consensus. We should always be questioning and re-assessing our beliefs.
But when people argue that Good Calories, Bad Calories got it all wrong, it would be nice if they read the book first. And then remembered what they read.
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Someone in comments linked to a study that reminded me of another study that demonstrated why body composition isn’t just about calories. Actually, both studies demonstrated why body composition isn’t just about calories.
First, the study linked in comments, which was reported in Science Daily:
Researchers at McMaster University have uncovered significant new evidence in the quest for the elusive goal of gaining muscle and losing fat, an oft-debated problem for those trying to manage their weight, control their calories and balance their protein consumption.
Scientists have found that it is possible to achieve both, and quickly, but it isn’t easy.
The reader who linked to the study did so because a gym rat once insisted that I had NOT (despite what I might think) lost fat and gained muscle at the same time. I posted about my exchanges with the gym rat more than three years ago. I nicknamed him “Cliffy” because his (ahem) “expert” arguments reminded me of the character from Cheers. In fact, Cliffy and I first had a go-around about why kids get fat, which I recounted in a different post.
Anywhere, here’s part of the post where I recounted Cliffy’s theories about changing body composition:
Cliffy also insisted I did not (contrary to what my mirror and scale were telling me) become both leaner and more muscular after I tightened up my diet and switched to Fred Hahn’s Slow Burn workout method. Cliffy explained that it’s physiologically impossible to gain muscle mass while losing fat mass, and in fact pretty much everyone who loses weight loses some muscle mass. He knew this because some body-building guru he worships said as much.
I tried telling him that I did indeed put on muscle even while losing weight, that my arms and chest and thighs had become noticeably thicker while my waist shrank, but Cliffy explained that I’m an idiot (and a fat, lazy old man) and only thought I’d gained muscle because the weight loss gave me more definition.
So I looked up a clinical study in which women lost body fat while gaining muscle mass and posted the reference. Cliffy read the study and replied that it’s sometimes possible for people who’ve never worked out and are therefore “untrained” to gain muscle while losing weight, but not for anyone who’s been regularly lifting weights – which I had been. When I asked how being “untrained” makes the physiologically impossible become possible, he explained that I’m an idiot (and a fat, lazy old man) and must not have been “trained” even though I’d been lifting weights regularly before switching to Slow Burn.
It is, in fact, possible to lose fat and gain muscle during the same time span, as the study in Science Daily demonstrated:
For the study, 40 young men underwent a month of hard exercise while cutting dietary energy they would normally require by 40 per cent of what they would normally require.
The researchers divided their subjects into two groups. Both groups went on a low calorie diet, one with higher levels of protein than the other. The higher-protein group experienced muscle gains — about 2.5 pounds — despite consuming insufficient energy, while the lower protein group did not add muscle.
Researchers were intrigued because the high-protein group also lost more body fat.
The high-protein group lost 10.5 pounds on average in four weeks, while the lower-protein group only lost eight. The high-protein also gained 2.5 pounds of muscle on average, while the lower-protein group merely maintained their muscle. So the additional fat loss in the high-protein group was more like five pounds.
I’m not suggesting we all run out and undergo the diet-and-exercise regimen these young men did – after all, even one of the researchers described the regimen as “grueling.” But there are a couple of important lessons in there even for those of us who adopt less-than-grueling routines.
One is that lifting weights is a excellent idea if you’re attempting to lose weight. Despite drastically cutting calories and losing weight quickly, both groups at least maintained their muscle mass.
The other lesson is that protein matters. The only difference between the two groups was the proportion of protein in the diet. The high-protein guys put on more muscle and lost more body fat. That’s why, as I explained in a previous post, I choose a high-protein diet over a ketogenic diet. I can’t stay in ketosis unless I restrict my protein to something like 50 grams per day. I believe I’m better off going high-protein.
The second study (the one the first study reminded me of) was one I first read about in the excellent book The poor, misunderstood calorie by Dr. Bill Lagakos.
Dr. Lagakos recounted a study in which adults who were deficient in growth hormone were divided into a treatment group and a control group. The treatment group was given growth hormone. There was no other intervention for either group.
After three-and-a-half years, body weight hadn’t changed significantly in either group. But the people treated with growth hormone gained 12 pounds of muscle and lost 12 pounds of fat on average. That’s a lot of additional muscle. If you don’t believe me, go buy 12 pounds of lean beef and stare at it for a moment.
So once again, we see that it’s possible to gain muscle while losing fat – this time because of a change in hormones. As Dr. Lagakos wrote:
They gained muscle and lost fat without a change in energy balance … this demonstrates that a particular hormonal milieu, in this case elevated growth hormone, is capable of regulating fat mass independent of energy balance.
That’s why it isn’t just about calories. Hormones tell your body what to do with those calories.
Every time you eat, you trigger the release of hormones. What you eat determines which hormones are released. Anyone who believes 500 calories of bread and 500 calories of beef produce the same hormonal response is simply ignorant.
You can probably guess which 500 calories I’d choose. And that’s why, despite what Cliffy insisted, I lost weight while putting on muscle.
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Sorry to bug off for an entire week, but it’s one of those pedal-to-the-metal situations at work. And to make things worse, the insomnia bug hit this week. It’s been awhile since I’ve dealt with that one.
So I’ve been writing code in the wee hours, catching a bit of sleep in the late morning or afternoon, then getting back to it.
I hope to return to something like a normal schedule after the Super Bowl — go Peyton!
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