Dec 14 2009
Still On That Low-Carb Diet
I have never been a fan of the low-carb diet craze – Atkins, South Beach, or whatever version you prefer. To me this was always a triumph of marketing over science. It is also an excellent example of how public opinion can be largely swayed by a few proponents and a compliant media, while the science goes off unnoticed in a different direction.
Dieting is also one of those issues that is more emotional than one might at first think. I have had the experience on more than one occasion of giving someone, in a very dry and calm fashion, my assessment of the evidence about low-carb diets, only to be met with righteous anger as if I had just trampled on a core tenet of their faith. People are often touchy about what they eat and how much they weigh, and for those who have lost weight and credit a low-carb diet, the published evidence seems irrelevant. “Well, it worked for me” is the almost ubiquitous response.
I also think that people have far too much confidence in their ability to estimate their own caloric intake. The suggestion that perhaps they consumed fewer calories on the low-carb diet and that was responsible for their weight loss is met with outright denial.
There have been some recent studies that cast further doubt on the efficacy and even safety of low carb diets. But first a little background.
The literature on dieting is vast and complex, and we must separate out many distinct questions. Different diets can be assessed for their efficacy in weight loss and control, their heart health, their risk for diabetes, satisfaction, and their overall healthfulness. Evidence also needs to be considered for short term and long term effects. Long term weight control efficacy seems to be largely a factor of ease of compliance.
Like most medical/biological questions, the clinical literature is complex and there are no perfect studies – so how the strengths and weaknesses of various studies are considered can have a dramatic effect on one’s overall opinion. Some studies are too short, they vary in how they monitor compliance with the diet and other variables such as exercise, and on which outcomes they measure. Weight, of course, is the obvious parameter to follow, but there is also mood, cholesterol, insulin levels, and cardiac and diabetes risk.
My quick summary of this complex literature is as follows:
- The evidence strongly supports the conclusion that weight loss and control is dominantly (if not completely) determined by caloric intake. All diets that result in weight loss do so by reducing calories, and the macronutrient make up of those calories is irrelevant (to weight loss). Apparent advantages of low-carb diets are likely related to decreased hunger, which results in decreased caloric intake – but this effect is short term (3-6 months at most) and there is no long term advantage.
- Weight loss diets, in general, do not work. Most dieters will experience short term weight loss, but about 95% will fail to maintain their weight loss long term. Regular exercise seems to be critical for long term weight management (and is good for overall health), as is making lifestyle changes in eating habits, rather than “going on a diet.” Even still – most dieters fail. This likely means that we need to focus our attention on cultural, lifestyle, portion-size, and food manufacturing variables rather than individual dieting as a public health strategy to reduce obesity.
- Low-carb, high-fat diets are likely not heart healthy, although this data is mixed. It seems that there are negative effects of a high-fat diet, but these are offset in the short term by weight loss. So if one loses weight on a low-carb, high-fat diet the net effect is positive for heart risk factors. But since weight loss on such diets is almost always short term, the long term health effects may be negative. But evidence is mixed.
A recent study adds to this literature. Researchers did a randomized controlled trial comparing low-carb (20% carbs and 60% fat) and low fat (60% carbs and 20% fat) diets for 8 weeks. All food was weighed and logged and designed to provide 500 calories less than expenditure. All subject lost weight on this diet to the same degree, supporting prior evidence that calories, not macronutrient content, determines weight loss.
They also found that insulin parameters were the same between the two groups. So there does not appear to be any difference in terms of risk of diabetes. However, they did find an increase in arterial stiffness in the low-carb group. This could translate to increased cardiovascular risk. Other studies have also linked low-carb diets to increased atherosclerosis, which would explain the increased stiffness.
A 20 year epidemiological study, however, showed no increased cardiovascular risk from low-carb diets. So as I said, there is reason for concern about the heart effects of low carb diets, but the data is inconclusive.
This latter study also found that getting fat and protein from vegetable rather than animal sources was associated with lower cardiovascular risk. And this highlights another bottom-line conclusion from the literature – the focus on low-carb vs low-fat may be entirely misplaced. For weight loss and maintenance, portion control and regular exercise seem to be the key factors and macronutrient ratios seem to be irrelevant.
In order to avoid type II diabetes, weight control is key. But also it may be helpful to eat low glycemic index carbohydrates – those that turn to sugar more slowly and therefore have less of a demand on insulin function.
For heart health, the amount of total fat may be a factor, but this is unclear. What is clear is that they type of fat is a significant factor. Vegetable sources of fat have a protective effect, while animal fat increases cardiovascular risk.
In other words – how much carbs vs fat one eats should not be a major concern, and may be largely irrelevant. While the types of carbs and especially fats is important for cardiovascular health.
To summarize, in my opinion here are the best diet recommendations that can be made from existing evidence:
- Eat a varied diet, mostly plant-based
- Limit carbohydrates with a high glycemic index (simple sugars and starches)
- Do not diet for weight loss. Rather, employ reasonable portion control and exercise regularly.
- Whatever you do for weight control, make sure it is sustainable long term. You should be happy with your diet and exercise should be fun and convenient. Anything that seems burdensome will likely not last and be of no long term utility.
- And most importantly – completely ignore diet fads, diet books, or any product that promises easy weight loss. They are scams.
“‘Well, it worked for me’ is the almost ubiquitous response.”
I’ll tell you, that is something I’ve heard over and over again from people I know that go on these diets or take vitamin regimens and so on. The other thing though that I hear from pretty much all those same people is, I think telling about why people defend their diets so fervently, and that is, “Trust me, I’ve done my research.” Usually, I end the conversation there unless I’m looking for a full-on and heated debate, but I would question what sources they’ve chosen to rely on since these same people tend to have an inherent distrust in medicine (including vaccines) and inherent trust of anything “Natural” which I interpret to mean “Alternative,” which of course really means “Not Science-Based.” So these people come to think of these diets as products of their own research and any negative statement as to the efficacy of what they are doing seems to be taken as an offense against their intelligence.
I passed this on to a coworker who is an Atkins fan, and his response (in part) was:
“But my biggest issue is with this statement that leads the article. ‘I have never been a fan of the low-carb diet craze.’ Blows the credibility of what follows. He is reading the data with a predisposition to validate his agenda. He’s not a neutral party looking at the data.”
I suggested to him that if having an opinion renders a scientist’s evaluation invalid, then there can be no more scientists.
I actually have some experience with the whole weight loss thing. A couple of years ago I made it my mission to slim down, as I was less than happy with my weight at the time. Being a science-minded guy, I knew that the most successful formula would have 2 components: 1) fewer Calories, and 2) convenience. I had no other considerations (unlike many who embark on a diet). So I started with meal replacement shakes (think Slim-Fast, then look down on the bottom shelf for the store brand; hey, I’m a cheapskate too
). Of course they worked. Quite well. TOO well, actually. I dropped about 55 pounds far more quickly than was probably advisable, giving myself gall bladder problems as a reward. Once I got to my target weight (which I have happily maintained since then), I tried to redesign my diet around a very simple formula. Take the 2000 Calorie intake suggested on nutrition labels and divide it up like this: for breakfast, 500 Calories. For lunch, 500 Calories. For dinner, eat whatever, around 1000 Calories. Oh, and avoid snacks pretty much all the time. What I found is that I really do need more than 2000 Calories to sustain my weight, so I still get a buffer. It means I can indulge just a little bit every day. It’s also trained me to look for hidden Calories, which prompted me to cut the sugar and creamer from my daily coffee habit (now I drink it black). What’s more, with some practice, you can actually get pretty good at estimating your Caloric intake just by looking.
So in summary, science FTW!
Since there do seem to be people who have lost weight on the atkins diet, maybe it would be better to frame the argument not that the atkins diet doesn’t work, but that it doesn’t work how you think it works. People who have lost weight on this diet may more readily accept this response.
@superdave: “You keep using that diet… I do not think it works how you think it works…”
“Inconceivable!!!”
Skeptics can diet too! Please don’t presume all weight-loss nuts are, well, nuts.
I was 305 lbs when I decided I needed to lose the weight. I did a lot of research using many of the techniques I learned from the skeptical movement and decided on a food log to track calories. This seemed to have the most evidence for success. Using these tools I changed my entire lifestyle. I no longer keep the diary and have added a fun exercise regimen to my lifestyle but have no maintained a weight of 185 lbs (+/- 5) for 14 months.
I can honestly say in this case science based dieting worked for me and Steve’s advice is spot on.
In my experience, anytime the topic turns in any way to “I may know something that you don’t,” people’s defences go up. That’s why I usually just stick to asking questions unless people are searching for answers or just looking for my take. If they feel that they’ve found the answer, it seems very similar to religion in that they don’t want to let that answer go.
I’m curious if in your search of the literature you turned up any studies that that analyze the complement to healthy weight loss, healthy weight gain? I cannot tell you how many advertisements for diet programs that promise a muscular male physique if you take creatine before working out (or is it after?), or consume X% of your daily calories as protein.
“Eat a varied diet, mostly plant-based”
Mostly plant based? Humm… well, I would ask for references as to why you promote this, but then it is a tit-for-tat with other papers supporting a larger portion to be from animal protein.
This is an emotionally charged subject. At this point, I have simply gone to observational evidence as to how food affects my body.
I have done this with various measures, such as metabolic panel, fasting blood glucose and triglycerides etc.
Then I tried several permutations of grains, meat, vegetables, processed carbs etc. And, I have repeated these permutations to measure if the effects are consistent.
Conclusions?
1. I have a wheat allergy.
I eat wheat and my skin becomes inflamed and sore around the scalp and in my beard. Then I get severe dandruff. My joints in my fingers ache, and I feel like I have a mild flu. After a couple of weeks of eating wheat based products my stomach is doing me in and I have to eat tums like candy.
Within a week of stopping consuming wheat, these symptoms disappear. I have tried this various numbers of times, logging my results with pictures etc.
I discovered this by trying a reduced carb diet. *shrug*
2. Fasting triglycerides are ~ 4000 on my usual diet (Yes… 4000… seems to be a family trait as my mother had the same issues) of refined carbs and grains, moderate vegetables and small amounts of meat.
Within three months of changing to a diet of meat, vegetables and fruit my numbers drop to around 100 with a really good LDL HDL ratio.
My weight drops at a nice rate of 1 lb per week without much problem, faster if I exercise (but not all that much faster).
I go on a veggie diet (no grains, since I have established my problems with wheat), and my numbers creep back up (HDL/LDL slowly, but triglycerides at a moderate pace to about a maximum of about 740), and I feel like crap. I start getting more hungry and eat more.
So, for me the data pretty well indicates that I do best physically on a diet of reduced carbs, no refined carbs if I can avoid it, and various meats of various cuts and fat percentages.
Anybody making blanket statements about how people should eat is someone I would question. What works for me, does not work well for my wife for instance.
As with most epidemiological studies, the data is inconclusive, and can be tuned to show what a researcher wants to show, or used by a marketing company to support their views.
And what is surprising is that you would promote a largely vegetarian diet from such a study. Or is it that you personally do well on such a diet, and the study only serves validate as to why?
They only thing I personally would promote is to try various combination of food for a fixed period of time while monitoring various indicators of health, blood work, and simply how you feel, and repeat a few times until you find something that works for you. Then try to stick with it if you can afford it.
I went on an atkins style diet once in highs school to lose weight, for about a month. It was the worst diet experience I’ve ever been on, I felt hungry all the time because I wasn’t eating food I like and weighed down from the fat. I started feeling so weak that my legs would tingle and feel as though they were going to buckle when I walked upstairs. I can’t believe I kept it up even that long, considering the awful effects, but I was desparate to lose weight and had been convinced this was the answer.
I later learned what actually constitutes a healthy diet. I’m actually vegan now (though I don’t think one needs to be vegan to be healthy) and I’ve lost 20 lbs over 4 years. I feel great and I’ve finally been able to stick to an exercise plan. Yay
Superdave – that is what I say, the evidence shows that you lost weight because of reduced caloric intake and/or increased expenditure. But some insist that it was not overall calories but the low-carb thing. The evidence just does not support that.
Rob T. – tell your friend that I was never a fan of low car because of the evidence – not because of any a priori agenda. I have nothing invested in this issue – other than, perhaps, I have to work to control my own weight and want to know what the evidence shows. I am just giving my reading of the evidence, which is in line with the consensus.
Michael – my opinions, as I stated, are not based on my own experience but on the literature – the research. I do not put much faith in individual anecdotes. They are too misleading.
The evidence clearly shows that fat from plants is good, and fat from animals is bad, so for heart health eating fruits, veggies, legumes, and nuts are good. I am not a vegetarian. Getting protein from lean meats and fish is fine. Just don’t overdo it.
Fruits and veggies are also a good way to get vitamins and minerals. But you need some meat also. Unless you are very careful and know how to have a vegetarian diet, it is easy to get vitamin deficiencies on a vegetarian diet. I see patients all the time with low B12 from an all veggie diet.
The consensus of opinion based on the evidence is that a varied diet is best, and most people could stand to eat more fruits and veggies.
Sorry Steven, but the evidence is no more clear that fat from plants are”good” and fat from animals are “bad”, than the evidence for the opposite. Buzz words such as “heart health” do not convince me, as they are ill defined.
There is no consensus on dietary fat sources in general, or at least one that seems to last more than about 12-15 years. (Eggs will kill you! Cholesterol will be the death of you! Oh wait, eggs aren’t bad for you…. etc.)
Anybody who points to the literature in this matter and asserts that one or the other is better, I would have to question how thorough they were in their literature research, how much they understand about the subject, or what their agenda may be.
(Well, those are questions I always ask regardless of topic… but you understand that mode of thought.)
The data is fairly clear about bio-absorbency nutritional densities for meat as compared to plant based diets. Such data is not only verified by nutritional assays, but in-vitro, in-vivo and in-situ tests for absorbency… (at least as accurate as any test for such absorbency can be)
The data is also a little more telling on certain hydrogenated fats, but even then much more study is needed.
I have read literally hundreds of medical studies and journal articles ranging back about 40 years. I have read studies without bias. All that can be stated with certainty is that in various decades the pendulum of opinion has swung back and forth as to which fat source is “healthier”.
Some decades have a spate of conclusions based on one stance, then the next it swings to the other side. No conclusion can be derived from such a data set.
Individual anecdotes are horridly misleading, and that is why I clearly state that what I did works for me and made no assertions to how it would affect others.
I also applied a large number of controls, and accounted for many variables in my personal tests. I applied the scientific method as best I could without having the ability to prepare an ensemble of identical test subjects.
So, while not willing (and unable) to state conclusively what is a better diet, I am more than willing to trust my own observations over that of some random doctor as to what works for me.
Another skeptic such as yourself could look at the studies and journal articles out there, and write a snarky titled blog “Still on that organic vegan breathairian diet?” and have just as much science to back them up.
Considering the crappy state of nutritional science (a soft science if there ever was one at this time) the best any lay person can do is research the effects on themselves until they find something that works.
The best thing a doctor can do is support such an exploration rather than picking a side and espousing that view.
Regards,
Mike
For myself, the problem has always been about gaining weight. High school wrestling also programmed in a few bad habits that had to be broken, but now it’s pretty simple: complex carbohydrates, fruit, lean proteins (as well as beans, nuts, etc.), and so-called “good fats” like nuts, avocados, and olive oil. Oh, and fiber. I think that’s the pretty standard prescription.
I think most people who are actually concerned about healthy eating know what’s healthy, but real life gets in the way (you’re late for work, so coffee is your breakfast, you have to wolf down a burger during a half-hour lunch break, then you have to pick up the kids, so you just grab pizza for dinner and so on). For my girlfriend, it was all about meal spacing and portion control, just putting the amount that she was supposed to eat in a separate bowl until she had trained herself to recognize the proper amount.
Mike,
We disagree as to the state of the evidence. No need to appeal to ad hominems.
Yes, the evidence is complex and often contradictory – like every complex medical question. You could use that argument to deny any almost medical conclusion.
But there is a strong signal in the noise. Through the 1980s research focused on total fat, and for a while cholesterol, and the predictions of the low-fat recommendations were never verified. It turned out that avoiding total fat was neutral and even possibly negative on cardiac outcomes.
Over the last 20 years it has become increasingly evidence that some dietary fats increase LDL, which increases cardiac risk, while others increase HDL, which has a protective effect. The science on this is now quite strong, in my opinion. Generally speaking, animal fat raises LDL while plant fat raises HDL.
This is the current consensus, and it is absolutely not irresponsible to recommend this.
I am not saying this is rock solid. There is still uncertainty – but these are reasonable recommendations and the best we can currently do.
The problem with the “what works for me” approach, is you don’t want to wait until you have a heart attack to know if you are on the right diet or not. We need experimental and epidemiological data. Using markers, like cholesterol and triglycerides, is reasonable, but it is impossible to control for variables, and these are only markers for clinical risk. It’s nice to have data from net outcomes.
Steven,
The problem with stating things in terms of generalities is that information can be lost, and erroneous conclusions can be drawn by the uninformed.
For instance, lets assume for the sake of argument there is indeed a well linked coronary risk factor with consumption of saturated fats. I.e increased LDL, which is but one indicator and may not even be the most important one. (And there are peer reviewed studies that indicate otherwise.)
Animal fat is primarily saturated fat.
Saturated fat increases LDL.
Increased LDL is a marker for increased risk of negative cardiac outcomes.
(Therefore) Don’t eat animal fat.
What is left to eat? “Plant fats”
Eat plants instead.
Well…
Various nuts and legumes are very high in saturated fats, as well as palm oil and coconut oils and the fat profiles of several other plant based foods. But no distinction is made on what plants to eat.
So where does that leave us? Advocating a diet derived from plants in general by no means guarantees us a diet free from the proposed causal substance, namely saturated fat.
Heck, there are even studies in sub-composition of various fatty acids that comprise saturated fat that indicate that those fatty acids can lower LDL etc.
Such a deductive chain also does not address the fact that plant matter “in general” is a poor source of complete protein, or other nutritional issues such as the good fat that you allude to that is present in significant quantities in animal meats.
Such a deductive chain may obscure a true causal mechanism, such as the possibility of phytochemicals in plants lowering the LDL rather than the absence of saturated fats.
There are also direct studies with large sample sets that a completely veggie free diet with only meat and fat lowers LDL, raises HDL and reduces triglycerides.
So how does current nutritional science explain this (or discount this)?
Well, frankly it cannot. (Yet)
And here is possibly the main problem with nutritional science:
It is not a predictive science (yet).
It has not reached the state where it can predict an outcome for a broad range of situations. It is still stuck in the “butterfly collecting” phase, where there are studies, correlations, meta-studies, epidemiological studies and the like. But there is very little predictive power in the field.
And without at least a modicum of predictive power, forming a consensus and making recommendations based on such a “weak science” may not be the best thing to do.
Regards,
Mike
Steven, what do you think of the work of someone like Gary Taubes, particularly his book “Good Calories, Bad Calories”?
To deny that macronutrient composition has any effect on weight control seems absurd in light of the fact that carbs spike glucose levels, which then leads to an increase of insulin, which then shovels fat into adipose tissue. So, on the metabolic level, it seems clear that eating carbs rather than protein or fat has a direct control over fat gain.
Caloric theories of weight gain miss the point that adipose tissue development is directly linked with the influx of carbs and moderating your metabolism so as to increase its ability to burn fat is much more important than trying to control for a oversimplified input-output model of metabolism.
Moreover, if the caloric theory is true, then why do you have cases where people are, say, have fat only on one half of their bodies but are skinny on the other? These cases seem to be the result of problems in metabolism, not caloric input/output. Eating under the caloric baseline might reduce weight, but controlling for macronutrient profiles will guarantee that you lose fat tissue, rather than muscles mass.
I recommend reading some of Gary Taubes research and then reevaluating the evidence for standard caloric theories. As Taubes shows, the overall evidence for both the fat-is-bad-for-your-heart hypothesis and the caloric weight gain theory is inconclusive and/or outright contradictory.
@orestesmantra
“Moreover, if the caloric theory is true…”
It is. Pretty fundamental physics requires this.
If you eat less than your body burns in a given period of time, you lose “weight”.
I give you 2000 kcal of sugar per day, and you burn 2500 kcal and you will have a deficit of 500 kcal.
I give you 2000 kcal of fat per day, and your burn 2500 kcal a day and you WILL have a deficit of 500 kcal.
There is no way around this fact.
Think about this: I give you 2000 kcal of sucrose in water once per day. You drink it all at once, you spike your insulin and it “shoves” the excess calories rapidly into your adipose tissues.
If you burn 2500 kcal that day, you still have a deficit of 500 kcal, even if you have to burn that adipose tissue to get it (or muscle, organs, tissues or what not.)
You may be able to eat foods that your body cannot process and wring every last erg of energy from, but all this means is that you can eat more of this type of food to obtain 2000 kcal than you can of other types of food. This does not mean you can violate the laws of thermodynamics.
Now, you can argue that certain foods can spike hormones that control how satiated you feel after eating, or that triggers you to want to eat more, but again this does not negate the principles of calories out > calories in will make you lose weight. All it does is make it more difficult to keep to this equation.
You may also argue that certain macro nutrients alter your ability to metabolize food, or render you ill so you cannot burn as many calories in a day. This still does not mean the caloric theory of food is wrong, simply that you need to find ways to increase your burn back up to 2500 kcal.
Finding a person that is “half fat and half skinny” does not disprove basic physics.
The calorie in vs calories is not an issue as far as I am concerned, so long as people understand what it means.
oreste – what you are trying to do is extrapolate from basic science about metabolism to net clinical effects. This is very difficult – to the point of being unreliable by itself. You need clinical studies of net outcomes.
The research shows that total calories are what matter for weight control- overwhelmingly. The study I cite above is just the latest.
It is probably true that those metabolic effects average out over time – eventually unused calories are stored. And calories are likely fungible – if you get energy from protein then more calories are available to be stored as fat.
I am familiar with Taubes position. He is anti low-fat, pro low-carb. But his views are outside the mainstream.
@orestesmantra
You may be interested in reading Bray, Obesity Reviews (2008) 9, 251–263 *
I have not read Taub’s book as of yet, but if he really thinks there can be weight gain while on a caloric deficit (more calories burned than consumed), I have to wonder at the efficacy of his physics education.
=(
* http://www.proteinpower.com/drmike/wp-content/uploads/2008/07/bray-review-of-gcbc.pdf
Is a link to the PDF, even if it is at a pro-protein diet site.
Mike
I am not advocating a vegetarian diet. I recommend a varied diet, including some meat.
My bottom line recommendations were, of course, simplified. But part of the point is, with diet it is better to have some simple rules of thumb that are true most of the time and will work for most people. I focus on the large factors – not fine tuning.
Steven,
Point taken.
I am always going on about societies tendency to pander to exceptions exceptions, to set policy based on those exceptions, and to hinder progress based on those exceptions.
I guess being aware of those exceptions is enough in this case.
I am just not convinced yet that nutritional science is able to set those rules of thumb to make exceptions just that, exceptions.
Regards,
Mike
The dispute over calories in/ calories out could probably be settled if the warring factions were to pay more attention to energy apportionment. By this I mean that we are not the only ones consuming the food that passes between our lips. About 2 kilograms of gut flora inhabit the digestive tract, feeding and multiplying as digesting food passes through. In fact, about half of the solid waste that exists our bodies each day is dead gut microbiota.
Food quality affects microbial activity in more or less predictable ways. For example, consuming lots of refined carbs or pure vegetable oils or separated animal fats tends to deprive microbes of elements they need to multiply efficiently. Thus, energy contained in mineral and vitamin deficient manufactured foods is more likely to be highly absorbed into the bloodstream whereas energy in foods that promote microbial replication would be less absorbed.
Mike and Steven, you might want to visit Gary Tivendale’s collection of documents for further enlightenment on this matter. http://www.scribd.com/Gary%20Tiv Do read his bio on the left side of the screen.
Now as for low-carb research, Christopher Gardner gave an interesting presentation a while back entitled Battle of the Diets: is Anyone Winning (at Losing)? http://academicearth.org/lectures/battle-of-the-diets Note what is said about insulin resistant and insulin sensitive study subjects.
Lastly, it seems like the biochemists are the only ones capable of sorting things out where heart disease is concerned. I urge you both to watch this 37 minute presentation by Dr. Bill Lands. http://omega-6-omega-3-balance.omegaoptimize.com/2009/11/10/why-omega6-fats-matter-to-your-health.aspx You’ll have to register to download the video but you don’t have to buy anything and no one is going to pester you afterward even though it may seem as though they might. The other video presentation I feel everyone should watch is an 89 minute lecture delivered by Robert Lustig. http://www.youtube.com/watch?v=dBnniua6-oM Note what Dr. Lustig says about Dr. John Yudkin’s work from 40 years ago.
I’ve just reached the age of reduced metabolic activity, and it sucks. My body still craves massive amounts of calories, but my growing gut seems to disagree. I’m thinking about cutting out the beer and Izze sodas.
Also, northern Illinois doesn’t have anywhere good to go hiking, reducing my energy expenditure. Anyone have any good hiking places in northern Illinois?
This nutrition/weight managment is a very interesting topic for several reasons:
First its an open scientific question and that should be interesting enough by itself
Its controversial which makes it more “spicy”
The answer isnt clear cut like say with homeopathy so there is some genuine mystery
and lastly its a real issue and it concerns us all because we all eat and we all want to look good and be healthy !
Lately i ve found myself preoccupied with this because i decided i should change my lifestyle so i quit smoking , started working out and tried to balance my diet.
The smoking part was simple and straightforward but the weight training/aerobic training/dieting plan part is a real mess.
I ve been looking around the net for information on these subjects but i keep finding alot of conflicting vague sources.Clearly theres alot of money at stake here and that muddles the issue.I try to keep a skeptical perspective but when i do i am left with no option but to admit i dont really know anything with any reasonable certainty.
Does anyone know any sources (preferably online) that treat the issue scientifically and with skepticism ? I am surprised i couldnt find any.Just like we should have science based medicine we should also have science based “fitness science”
Steven
In regard to “animal fats increase cardiovascular risk”, what do you think of this recent comment?
http://wholehealthsource.blogspot.com/2009/12/dirty-little-secret-of-diet-heart.html
This diet debate drives me batty.
The general guidelines for a well-balance diet are just that, general guidelines which for most of the public are going to work.
There is an variation in the requirements for humans.
If you want an interesting overview of the topic, there is a book called Biochemical Individuality.
http://www.anapsid.org/aboutmk/biochem.html
I do think some people will do better on a low carb diet, I think it has its place, however, for the majority of people, this isn’t going to be a diet that can be maintained for life.
The New England Journal of Medicine recently reviewed the low carb diet (again) and found that there may be risk factors for cardiovascular disease.
Smith, SR (2009). A Look at the Low-Carbohydrate Diet. The New England Journal of Medicine, 361 (23) 2286-8, December 3, 2009.
It is basically the review of an animal study:
Foo SY, Heller ER, Wykrzykowska J, et al. Vascular effects of a low-carbohydrate high-protein diet. Proc Natl Acad Sci