Quote:
Originally Posted by joltyness
Studies have shown that a strict macro balance doesn't really affect weight loss very much
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There are a couple major flaws in these studies (more limitations than flaws, because often they're addressed in the actual research - just not in the popular reporting of the researches findings. The limitations are mostly related to the study method itself and the subject pool.
As to the method, very often subjects are randomly assigned to different macro balances. Then the groups are compared. This means that if some people respond better to a low-carb diet and an equal number respond better to a high-carb diet, you're going to see "no difference" between the groups. If the differences are incredibly amazing, there's a chance that the researcher may notice (patients who did extraordinarily well or poorly compared to the rest of their group), but if the advantages are more subtle, that advantage will be lost during the statistical analysis (especially if there are other people in the other group who responded equally well or poorly on the other macro distributions).
This method assumes that all people are the same, and it's an unfair assumption. However if you assume that all people are not the same, you have to develop the study in a different way to determine which diets are best for which people. Most of the research is not designed this way. And the ones that have been, have found different results. For example there's been some researchers which has found that diabetics, people with PCOS, and insulin resistance do better on lower carb diets than on other diets).
And this leads into the other flaw, that of the chosen subject pool. Usually research is done in the university setting, and the subject pool tends to be university students - on the whole, younger, fitter, and healthier than the average. And to complicate things further, people with any comorbid health issues are often purposely excluded from the studies, to make the results easier to analyze (and to eliminate the complications of dealing with possible health risks to the subjects). This means that if low-carb is more effective for diabetics and folks with other endocrine or metabolic disorder, we'll never know because people with those disorders were often excluded from those studies (either purposefully or because endocrine disorders are less common in the subject pool).
I strongly suspect that low-carb diets benefit people with insulin issues more so than other segments of the population (I suspected this even before the research started coming out that supports that conclusion). I believe that some folks respond to different diets differently. Some respond best to a diet higher in calories from protein and fat, and others responb best to a diet higher in calories from carbohydrates. I also believe that young, healthy, fit bodies process calories more "fairly," than older, less healthy bodies. "A calorie is a calorie," may apply when you're 20 in decent health, and not when you're 50 and have diabetes.
Currently there aren't many studies that have tested these hypotheses. By not including (and/or not looking for) people who do respond more favorably to one type of macro balance than another, the research can't find them.
I can only suggest that people do their own research. Experiment with different macro balances (allowing 3 months for each diet variation), and repeat the experiments several times to be sure that the patterns you see aren't just coincidence.
Without at least a couple college courses in experimental design and statistics (and even with them), it's hard to be sure that you're noticing "real" patterns and not coincidence or placebo effect, but until the research catches up, we're left to be scientist AND lab rat.
Sometimes low-carb can seem to work better, because your body needs less water to operate on a low-carb diet, so the body flushes this extra water in the first weeks of the diet. The person things "wow, I can lose so much faster on low-carb," but it's really just the release of the un-needed water."
Likewise, when switching back to higher carb eating (because the body has to pick up the extra water it's going to need in those first couple weeks), people think "when you're on low-carb, you can never switch to any other type of diet, because you'll gain weight like mad - even if you're on starvation calories."
If you ignore the first month and compare month's two and three - you may find that you do no better or worse on low-carb as high-carb.
Other people will find important differences.
For example, in examining my food logs and symptom logs (my doctor recommended the symptom log to find patterns to my symptoms), I learned that my normally very low body temperature is higher (closer to normal) on low-carb (this may mean my metabolism is higher on low-carb, which would explain why to lose about the same amount of weight I can choose either 1500 traditional diet, or an 1800 calorie low-carb diet).
I was truly shocked to see any difference, because all my life I truly did believe that all calories burned equally.
Another difference I discovered was that low-carb controlled hunger better. This was a miracle in itself, because all of my life, I've lived with 24/7 hunger so severe I called it "rabid hunger." I'm hungrier on 5,000 calories of high carb eating, than on 1,000 calories of low-carb eating. With carbs, especially refined carbs, but even with concentrated whole-carb foods like fruit - the more I eat, the hungrier I get.
I don't believe that's true for everyone. I don't even believe it's always been true for me (the carb hunger yes, the metabolic advantage to low-carb, no).
When I was younger, I didn't notice any dramatic difference (except during the first two to three weeks) between the weight loss from low-carb or high-carb (though I never gave low-carb much of a chance, because I thought it was unhealthy).
Because there have been some newer studies that have found low-carb to have an advantage in some groups (the type II diabetics and the insulin resistant), I think the science is starting to ask the right questions (not whether low-carb more effective than high-carb for everyone, but what macro-balance works best for which people).
There's also anectdotal evidence that low-carb may be more beneficial for people with hypothyroid and other endocrine disorders as well as fibromyalgia and chronic fatigue (but to my knowledge, no research yet).
I have no doubt that the research will eventually catch up, but for now we've got to experiment ourselves.