(This blogpost is mostly about me and not about science. For those who come here for the science, please feel free to skip it.)
As time passes, it becomes more and more obvious that the low-carb lifestyle offers many metabolic benefits. It reduces blood sugar and blood insulin, lowers blood pressure, decreases triglycerides and raises HDL cholesterol. For a summary of these effects, check out my blogpost reviewing three low-carb studies published in three well-respected journals.
Nevertheless, the reason most of us started doing low-carb was not for its health benefits but for weight loss. And unsurprisingly the three studies also showed that low-carbing works as well or better than other forms of dieting for weight loss and weight maintenance.
Nearly eight years ago I read Dr. Atkins' New Diet Revolution (DANDR)and was struck by the fact that his approach to dieting was based on solid science and was presented in a way that was easy to understand. Before long, I knew the book inside out and followed it to the letter. I did indeed make my goal weight and have (almost) maintained it since then. (For those who like to see if I practice what I preach, I report my weight weekly on the Maintain Lane at Low Carb Friends.) Recently I began re-reading DANDR and had a couple of thoughts that I'll share with those of you who are using the low-carb lifestyle to lose weight. You can decide if they're deep thoughts or not.
1. Low-carb is good for weight loss, but it's not perfect.
The low-carb boards on the internet are populated with hundreds of people who have lost some weight doing low-carb, but have not managed to make it to goal. It goes without saying that if you lose weight on low-carb, you have to keep doing low-carb or the weight will come right back. But why is it so hard for us to get all the way down to our goal weight even if we keep our carbs strictly below 20 or even very close to zero?
In DANDR, Dr. Atkins says to count carbs not calories. One of the reasons this works is that low-carbing produces what Dr. Atkins called a "metabolic advantage." As we change over from metabolizing carbs for energy to metabolizing fat for energy, our bodies perform somewhat inefficiently. If we use Ketostix, we'll see that we excrete a large amount of unused energy in the form of urinary ketones. We also tend to experience an increase in body temperature. However, after a year or so of low-carbing, we become fully keto-adapted and our bodies are able to utilize nearly every scrap of the energy we consume. The Ketostix no longer change color.
One of the things that doesn't change over time is that low-carbing keeps our insulin levels lower than they would be on a high-carb diet. This means that our bodies are better able to mobilize our stored fat, and we don't experience the constant hunger that results when we can't properly access our fat stores. In addition, foods that are high in fat and protein tend to satitate us much more quickly than do carb-rich foods. Finally, the ketosis produced by low-carbing has the wonderful side effect of decreasing our appetite.
So by counting carbs we can lose some weight, and we may even lose a large amount of weight. However, the sad truth is, Calories Count. In the long run, the number of calories we take in must be less than the number of calories we expend. Granted, when we low-carb we may be able to burn more calories than our peers thanks to a faster metabolism, a greater willingness to exercise, and the loss of ketone calories by excretion. But we can't fool Mother Nature. In order to lose weight, the calories in must be less than the calories out.
I had suspected this before, but just this week I've proven it to myself by using Dr. Atkins' Fat Fast. I have done low-carb and I've done zero-carb, but the most weight I could get off was a fraction of a pound a week. By doing the Fat Fast, I've stayed at 1000 calories per day and the weight has fallen off. Yes, it's nearly zero carbs, but as I said, I've done zero-carb and have lost weight at a snail's pace, if at all. What I haven't done before is intentionally cut my calories. To be sure, the Fat Fast is not a healthy long-term weight loss plan, but it does show that if carb counting alone isn't producing a weight loss, carb counting plus calorie counting is the next necessary step.
2. Too much protein can act like too many carbs.
While Dr. Atkins had lots to say about controlling our carb intake, for some reason he didn't warn his readers that eating too much protein can mimic the effect of eating too many carbs. People who have type 1 diabetes, or people who have type 2 diabetes and are using insulin, know something that most of the rest of us don't know. Eating excess protein raises your blood sugar.
Back in the summer of 2009 I wrote three blogposts on this topic: Protein Intake and Blood Glucose Levels, Observations on Protein Intake in Low-Carbers and How Can Eating Excess Protein Raise Blood Glucose? My readers participated in gathering data for these posts, and what we discovered was that when excess protein is consumed, it is converted to glucose. In younger people this did not show up on the blood glucose meter. In most cases they were able to secrete enough extra insulin to maintain a postprandial blood sugar in the vicinity of 85 mg/dl. However, in both low-carbers and zero-carbers over 50, it was not unusual to have a 30-40 mg/dl rise in blood glucose after consuming a large amount of protein.
Dr. Atkins did say that eating lots of protein has never been shown to cause kidney damage. And consuming good quality protein is essential to maintain our bones, muscles and organs. But for those of us who watch our carbs religiously, it's also important to watch our protein intake. A large excess of protein acts like carbs and can have a similar effect, especially in people who are prone to diabetes.
In closing, most of what Dr. Atkins said in his books has stood the test of time. But from my personal experience, a couple of points seemed to go missing. For those who are having a hard time making it to their goal weight, it might be helpful to consider (1) the importance of counting calories and (2) the carb-like effects that can be caused by excess protein intake.
11 comments:
Still a sciencey post, Stargazy. :)
Do you think the type or quality of protein affects the rise in BGL? Incomplete vs complete, animal based vs plant?
I'd hazard a guess that both glucagon and various amino acids would be variables.
I think part of the problem is that a lot of people are afraid to eat too much fat, so they tend to make it a point to eat more protein and avoid adding fat. This is what happens when an entire population has been indoctrinated to believe that fat is bad. Even some of those who are eating low carb or paleo can't let go of it.
The other problem is, people think they can look like super models on a magazine cover. Those models are airbrushed in Photoshop and are fake. So when they don't lose enough weight to look like they're borderline anorexic (or maybe even completely anorexic) they think they've failed.
Calories count I think, but not as much as the nonsense the USDA spouts, about how eating 100 calories less will cause you to lose weight, and eating 100 calories more will cause you to gain weight. If our bodies truly were like bank accounts, the human race wouldn't have survived, we would have become extinct.
Hi, Mike! I can't talk without speaking science, so there you go. I think (but have no citations to prove it) that incomplete protein is probably more likely to raise blood sugar than complete protein. It can't be used to repair tissues, so it has to be dealt with in some way. The ketogenic amino acids would go to energy formation (raising blood glucose via the glucose-alanine cycle) and the glucogenic ones would be used to form glucose, raising blood sugar in the process. The glucose, in turn, could be burned for energy or stored as fat.
You're right about the glucagon. I didn't want to add even more words to an already-long post, so I skipped that. For those who are reading this, when protein is eaten, insulin is released in anticipation of the need to store the amino acids that will be present after the protein is broken down. Because the insulin will also cause blood sugar to fall, the pancreas also releases glucagon. That causes the liver to release its glycogen stores into the blood as glucose, preventing us from becoming hypoglycemic. However it may also contribute to an excess of blood glucose depending on the ability of a particular individual to regulate his or her blood sugar.
Hi, Tonya! I think you're correct about the fat. We have been indoctrinated from all directions that it's bad for us, and it's hard to overcome that idea.
I agree that some of us have an unrealistic idea of how our bodies will look after dieting, but others have seen fat people around them for so long that they really don't know what a healthy weight looks like. Here is a post that discusses that.
And regarding your comment about the USDA, you're right. They don't seem to realize that our bodies can easily shift our energy expenditures to match a low-calorie intake, especially when it's not done in a low-carb context.
This post explains why some low carbers, including famous nutrition experts and bloggers, remain seriously overweight, even obese. They are still taking in more calories than they use, and they may be undercounting carbs if they are consuming supposedly low carb breads, tortillas, cookies, and other processed foods. Jenny at Diabetes Update blogged about how testing of blood sugars after eating showed that Dreamfields Pasta is metabolized into glucose just like regular pasta. In the freezer section of the supermarket recently, I saw a loaf of St. Alvaro's low carb bread for diabetics. I read the ingredients and found sprouted wheat berries listed first followed by other grain products. The bread was made mostly from grains. There is no way this bread can be low carb even if it's bulked with inulin and other nondigestible fibers.
I finally cut out cheese because it was hyperpalatable to me, especially if melted, and I'd eat too much, preventing that elusive ten-pound weight loss I've been striving for the past three years. I've dropped 4 pounds in the past month, a good result considering I'm at the high end of normal weight according to BMI charts and don't exercise other than an occasional walk or lifting dumbbells.
I get Gary Taubes' explanation about how the body can metabolize more efficiently or less efficiently in response to calorie input, but at some point, the body simply can't burn up all of what's being ingested, and at some point, the body can't down-regulate metabolism to avoid burning stored fat, which was stored precisely to be used later.
I have shed 10-20 pounds three times in my adult life, and all three times, I controlled portions. When I continued to control portions, I stayed slim. Maybe other people can eat whatever they want and stay skinny, but I'm not one of those people. Low-fat or low-carb, I do need to watch how much I put on my plate and avoid snacking between meals.
Always look forward to your posts, Stargazey.
This is a great post outlining some major caveats re the low-carb diet! I would have added one more ... eating lots of industrial low-carb products can derail an otherwise good diet.
All those sugar alcohols may not be affecting your blood sugar, but they aren't necessarily benign re weight loss.
Folks should also be skeptical of other reduced carb products: see Jenny's review of a study looking at Dreamfields pasta for example (http://ow.ly/3TQDp).
To add to this discussion, I'd like to bring up what I read on gettingstronger.org. The author, Todd Becker, seems to say that even low carbers don't get their basal insulin levels low enough to get as lean as they would like. He promotes strength through stress- like slow, steady weightlifting builds muscle- and not giving in to cravings and even skipping meals to bring down basal insulin levels. Of course he says it much better in this article: http://gettingstronger.org/2011/02/does-insulin-make-you-fat/#more-2076
In it, he addresses the carb count versus calorie count arguments and while he finds some validity on both sides, does, in the end, promote eating less food less often for ultimate leanness (but more because it lowers basal insulin that for calories in-calories out). At least that is my interpretation.
It's interesting to me that almost everything is expressed in terms of "target weight." That's a concept that is fraught with problems.
First, as a number of people have noted, it is possible to aim for an impossibly skinny look (though I don't think that's the problem most people face).
Second, "weight" is a poor target. It works well enough as a rough indicator when you are obese, but it is very rough. You can lower your weight by cutting off your left leg. That doesn't mean an improvement in your health.
Third, "weight" says nothing about body composition. I've been monitoring my body composition. I got down to 12% body fat eating low-carb without consciously restricting calories. But I gained almost 10 pounds of muscle getting there. My fat loss was considerably greater than my weight loss. If you pick the wrong "target weight," you may be fighting the wrong battle.
There is something in what you say in your post, but I don't think it is necessarily all about calories. They may certainly play a role.
I think the real problem is that when one gets to non-obese levels of body fat, everything becomes more idiosyncratic. For most people, low-carb s a clear pathway out of obesity, but when you get low enough in body fat (and "low enough" is different for different people), it's a far more complicated story.
I'd like to get down to around 10% body fat. But these days if I cut calories on an ongoing basis, my metabolism falls (and I get cold hands and feet). I'm playing with underfeeding and overfeeding cycles and some other things.
I'm not sure what all the factors are. But based on experiences of many people, it's clear that things are much more complicated once you have lost all of the truly pathological fat.
Hi, David! You're absolutely correct, of course.
You made me laugh, too. I forget that many of my readers are men who approach weight and fitness with steely-eyed concentration. If you read a few comments over at Low Carb Friends, you'll see that most women (and some men) don't approach weight loss that way. Once they've decided on low-carb, the questions they have will concern modifications around the edges--can they go above induction-level carbs, should they count fiber, is caffeine okay, how much cheating is allowed?
And after three years of low-carbing they're still stuck at 179 or 250 pounds and wonder why it is that they can't get off that plateau. For them, muscle mass versus fat mass isn't really the issue. They can cite Dr. Atkins' books chapter and verse, but they are still obese and don't really know why.
I wrote this post for those people. They know about candida and thyroid levels and healthy low-carb cooking. They feel much better than they did on the Standard American Diet. But their BMI stays above 30, and they have decided that they will be stuck there forever.
For them the message is, keep on doing low-carb, but COUNT YOUR CALORIES. It's good to keep track of body fat percentages and measurements and exercise and idiosyncratic features along the way. It's also easy to use those variables to make excuses for why weight loss isn't happening. If you have a healthy goal weight and you never seem to get close to it, please consider the unthinkable - COUNT YOUR CALORIES.
(And for people like you, David, keep on keeping on. It seems that you're approaching life in a very rational way.)
Hi, Stargazey--
Cutting calories may be the answer in some cases. But I worry a lot about prolonged underfeeding. I'd be inclined to throw in a day of excess calories at least once a week, just so I didn't encourage my body to downshift metabolism.
You are certainly right about excess protein--especially certain highly digestible proteins. The Eades have a program called the 6 Week Cure. It starts off with most of your daily nutrition coming from whey shakes. A surprising number of people reported that whey results in huge blood sugar spikes.
Of course, those people who check their blood sugar constantly are usually diabetic, so they aren't exactly a cross-sectional sample. But other quirky groups--bodybuilders, for example--also report blood sugar spiking with whey.
Of course, the bodybuilders view this as a virtue, since if whey is taken before a workout, the resulting insulin spike helps drive nutrition into the muscle cells.
(Keep the posts coming. This is one of my favorite nutrition blogs)
Thanks for your excellent comments, David. Right now, I'm not posting because I don't have anything new to say. I know that my readers have limited time, and I don't like to waste it by offering fluff.
Thanks for the information on the Eades' "6-Week Cure for the Middle-Aged Middle." I found a link here. Sure enough, all those whey protein shakes caused spikes in blood sugar, similar to what we saw with zero-carb.
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