Diet Quality (macros) may affect Metabolism during Weight Loss

EvgeniZyntx
EvgeniZyntx Posts: 24,208 Member
Just ran across this research thanks to a recent MFP discussion and thought it was worth its own thread.

http://jama.jamanetwork.com/article.aspx?articleid=1199154

Conclusion: Among overweight and obese young adults compared with pre–weight-loss energy expenditure, isocaloric feeding following 10% to 15% weight loss resulted in decreases in REE and TEE that were greatest with the low-fat diet, intermediate with the low–glycemic index diet, and least with the very low-carbohydrate diet.

Interesting. It supports the idea that diet make-up affects CICO.

Average differences in TDEE are very surprising...

jpc120005f3.png


The decrease in REE from pre–weight-loss levels, measured by indirect calorimetry in the fasting state, was greatest for the low-fat diet (mean: –205 [–265 to –144] kcal/d), intermediate with the low–glycemic index diet (–166 [–227 to –106] kcal/d), and least for the very low-carbohydrate diet (−138 [–198 to –77] kcal/d;

The decrease in TEE, assessed using the doubly-labeled water method, also differed significantly by diet (mean [95% CI], −423 [–606 to –239] kcal/d for low fat; −297 [–479 to –115] kcal/d for low glycemic index; and −97 [–281 to 86] kcal/d for very low carbohydrate; overall P = .003; P for trend by glycemic load < .001). This result was not materially changed when substituting measured respiratory quotient (RQ) for calculated food quotient (FQ). Neither total physical activity nor time spent in moderate- to vigorous-intensity physical activity differed among the diets.

Replies

  • Emilia777
    Emilia777 Posts: 978 Member
    edited May 2015
    Interesting, thanks for sharing. I don’t have time to read in detail, but I though I’d share the macro breakdown of every diet for ease of discussion:
    • low-fat diet (60% of energy from carbohydrate, 20% from fat, 20% from protein; high glycemic load)
    • low–glycemic index diet (40% from carbohydrate, 40% from fat, and 20% from protein; moderate glycemic load),
    • very low-carbohydrate diet (10% from carbohydrate, 60% from fat, and 30% from protein; low glycemic load)

    One thing that concerns me is the higher protein content of the low-carb diet, and how that may have impacted the results. The identification of the effect of each macro is not precise.
  • ndj1979
    ndj1979 Posts: 29,136 Member
    tagging to follow the discussion ..

    was protein consumption the same in all three groups?
  • Emilia777
    Emilia777 Posts: 978 Member
    edited May 2015
    ndj1979 wrote: »
    tagging to follow the discussion ..

    was protein consumption the same in all three groups?

    I wondered that too, and the fact that it isn’t makes me wonder about the results.

    Here is a breakdown of the diets, with g/day per 2000 cals, for those of you who aren’t bit fans of percentages:
    m_jpc120005t1.png
  • ndj1979
    ndj1979 Posts: 29,136 Member
    Emilia777 wrote: »
    ndj1979 wrote: »
    tagging to follow the discussion ..

    was protein consumption the same in all three groups?

    I wondered that too, and the fact that it isn’t makes me wonder about the results.

    Here is a breakdown of the diets, with g/day per 2000 cals, for those of you who aren’t bit fans of percentages:
    m_jpc120005t1.png

    thanks...

    interesting the protein was higher in the low carb group. I would have thought they would have wanted to keep it constant for all groups...
  • Emilia777
    Emilia777 Posts: 978 Member
    edited May 2015
    ndj1979 wrote: »

    thanks...

    interesting the protein was higher in the low carb group. I would have thought they would have wanted to keep it constant for all groups...

    Exactly! I think this confounds the results.
  • _lyndseybrooke_
    _lyndseybrooke_ Posts: 2,561 Member
    The "run-in diet" is what I'm doing long-term. Never tried the others, nor do I see any reason to try any of them after seeing the results of the study. 50g carbs a day? I think not.
  • ndj1979
    ndj1979 Posts: 29,136 Member
    The "run-in diet" is what I'm doing long-term. Never tried the others, nor do I see any reason to try any of them after seeing the results of the study. 50g carbs a day? I think not.

    for realz, I would not been able to lift the barbell on just 50 grams of carbs a day ...
  • Emilia777
    Emilia777 Posts: 978 Member
    edited May 2015
    ndj1979 wrote: »
    The "run-in diet" is what I'm doing long-term. Never tried the others, nor do I see any reason to try any of them after seeing the results of the study. 50g carbs a day? I think not.

    for realz, I would not been able to lift the barbell on just 50 grams of carbs a day ...

    Not with all the weight you put on it :wink:.
    50g of carbs is too low to be worth it for me also. That’s barely any ice cream.
  • EvgeniZyntx
    EvgeniZyntx Posts: 24,208 Member
    edited May 2015
    Thanks Emilia for the added elements.

    I too look at these diet choices and say, "Nope". Low carbing certainly has issues for active performance, IMHO. But I think that this is interesting info in that it highlights more the importance of fat, and what happens on a low fat diet.
  • _lyndseybrooke_
    _lyndseybrooke_ Posts: 2,561 Member
    Emilia777 wrote: »
    ndj1979 wrote: »
    The "run-in diet" is what I'm doing long-term. Never tried the others, nor do I see any reason to try any of them after seeing the results of the study. 50g carbs a day? I think not.

    for realz, I would not been able to lift the barbell on just 50 grams of carbs a day ...

    Not with all the weight you put on it :wink:.
    50g of carbs is too low to be worth it for me also. That’s barely any ice cream.

    It's almost exactly the amount of carbs I save for dessert every night. It would be hard to go carb-less for the rest of the day, because giving up my nightly ice cream is simply not gonna happen.
  • ndj1979
    ndj1979 Posts: 29,136 Member
    Thanks Emilia for the added elements.

    I too look at this and say. Nope. Low carbing certainly has issues for active performance, IMHO. But I think that this is interesting info in that it highlights more the importance of fat, and what happens on a low fat diet.

    any thoughts on why they did not keep protein consistent?
  • Emilia777
    Emilia777 Posts: 978 Member
    @LyndseyLovesToLift Totally understand that. Some things are just not worth it.

    @EvgeniZyntx I definitely agree that it’s interesting - thanks for posting it! I’m actually trying to eat more fat, so it’s a good reminder to be more diligent about it.
  • coraborealis80
    coraborealis80 Posts: 53 Member
    Can I just tell you all, you made my day by analyzing the science. I see it so rarely on these boards. And I have to say, we know it affects CICO, the issue is more of the exactly how's.

    I agree with the others though-the protein should not have been adjusted so greatly, however, the reasoning makes sense. The method's section discusses how each was developed and the reasoning.

    "The run-in diet was consistent with the Acceptable Macronutrient Distribution Range specified by the Institute of Medicine,15 with protein intake at the upper end of the range to enhance satiety during weight loss.16

    The low-fat diet, which had a high glycemic load, was designed to reflect conventional recommendations to reduce dietary fat, emphasize whole grain products, and include a variety of vegetables and fruits.17

    The low–glycemic index diet aimed to achieve a moderate glycemic load by replacing some grain products and starchy vegetables with sources of healthful fat and low–glycemic index vegetables, legumes, and fruits.

    The low-fat and low–glycemic index diets had similar protein and fiber contents.

    The very low-carbohydrate diet was modeled on the Atkins Diet and had a low glycemic load due to more severe restriction of carbohydrate. We provided 3 g of fiber with each meal (Metamucil, Procter & Gamble) during the very low-carbohydrate diet as recommended.11

    To ensure micronutrient adequacy and minimize the influence of micronutrient differences among test diets, we gave each participant a daily multivitamin and mineral supplement."

    I'm also concerned with the fact that they used a multivitamin, as several vitamins and minerals cancel each other out or enhance each other when presented together, and some of those affect weight loss. For example, calcium should not be taken together with iron, copper, or zinc, but calcium affects weight loss so much that the Mayo suggests taking calcium supplements if you are not a high dairy consumer. If the meals weren't planned carefully, this could also affect results, and since neither the menu nor micronutrient breakdown are available, we don't have much to go on.
  • EvgeniZyntx
    EvgeniZyntx Posts: 24,208 Member
    edited May 2015
    ndj1979 wrote: »
    Thanks Emilia for the added elements.

    I too look at this and say. Nope. Low carbing certainly has issues for active performance, IMHO. But I think that this is interesting info in that it highlights more the importance of fat, and what happens on a low fat diet.

    any thoughts on why they did not keep protein consistent?

    Edit: see post above.
  • ndj1979
    ndj1979 Posts: 29,136 Member
    Can I just tell you all, you made my day by analyzing the science. I see it so rarely on these boards. And I have to say, we know it affects CICO, the issue is more of the exactly how's.

    I agree with the others though-the protein should not have been adjusted so greatly, however, the reasoning makes sense. The method's section discusses how each was developed and the reasoning.

    "The run-in diet was consistent with the Acceptable Macronutrient Distribution Range specified by the Institute of Medicine,15 with protein intake at the upper end of the range to enhance satiety during weight loss.16

    The low-fat diet, which had a high glycemic load, was designed to reflect conventional recommendations to reduce dietary fat, emphasize whole grain products, and include a variety of vegetables and fruits.17

    The low–glycemic index diet aimed to achieve a moderate glycemic load by replacing some grain products and starchy vegetables with sources of healthful fat and low–glycemic index vegetables, legumes, and fruits.

    The low-fat and low–glycemic index diets had similar protein and fiber contents.

    The very low-carbohydrate diet was modeled on the Atkins Diet and had a low glycemic load due to more severe restriction of carbohydrate. We provided 3 g of fiber with each meal (Metamucil, Procter & Gamble) during the very low-carbohydrate diet as recommended.11

    To ensure micronutrient adequacy and minimize the influence of micronutrient differences among test diets, we gave each participant a daily multivitamin and mineral supplement."

    I'm also concerned with the fact that they used a multivitamin, as several vitamins and minerals cancel each other out or enhance each other when presented together, and some of those affect weight loss. For example, calcium should not be taken together with iron, copper, or zinc, but calcium affects weight loss so much that the Mayo suggests taking calcium supplements if you are not a high dairy consumer. If the meals weren't planned carefully, this could also affect results, and since neither the menu nor micronutrient breakdown are available, we don't have much to go on.

    Thanks for the breakdown of each diet.

    My concern on not controlling for protein is that would that not skew the numbers in favor of the diet/groups with the higher protein intake? As protein causes your body to work harder to break foods down and is typically associated with a higher TEF and would also increase TEE...?

    feel free to correct any flaws in my thinking....
  • Emilia777
    Emilia777 Posts: 978 Member
    ndj1979 wrote: »
    Thanks for the breakdown of each diet.

    My concern on not controlling for protein is that would that not skew the numbers in favor of the diet/groups with the higher protein intake? As protein causes your body to work harder to break foods down and is typically associated with a higher TEF and would also increase TEE...?

    feel free to correct any flaws in my thinking....

    What I find odd is that they mention this but just dismiss it.
    The thermic effect of food (the increase in energy expenditure arising from digestive and metabolic processes) dissipates in the late postprandial period and would not affect REE measured in the fasting state. Because the thermic effect of food tends to be greater for carbohydrate than fat,24,25 it would also not explain the lower TEE on the low-fat diet. Although protein has a high thermic effect of food,16 the content of this macronutrient was the same for the low-fat and low–glycemic index diets and contributed only 10% more to total energy intake with the very low-carbohydrate diet compared with the other 2 diets.
  • EvgeniZyntx
    EvgeniZyntx Posts: 24,208 Member
    ndj1979 wrote: »
    Can I just tell you all, you made my day by analyzing the science. I see it so rarely on these boards. And I have to say, we know it affects CICO, the issue is more of the exactly how's.

    I agree with the others though-the protein should not have been adjusted so greatly, however, the reasoning makes sense. The method's section discusses how each was developed and the reasoning.

    "The run-in diet was consistent with the Acceptable Macronutrient Distribution Range specified by the Institute of Medicine,15 with protein intake at the upper end of the range to enhance satiety during weight loss.16

    The low-fat diet, which had a high glycemic load, was designed to reflect conventional recommendations to reduce dietary fat, emphasize whole grain products, and include a variety of vegetables and fruits.17

    The low–glycemic index diet aimed to achieve a moderate glycemic load by replacing some grain products and starchy vegetables with sources of healthful fat and low–glycemic index vegetables, legumes, and fruits.

    The low-fat and low–glycemic index diets had similar protein and fiber contents.

    The very low-carbohydrate diet was modeled on the Atkins Diet and had a low glycemic load due to more severe restriction of carbohydrate. We provided 3 g of fiber with each meal (Metamucil, Procter & Gamble) during the very low-carbohydrate diet as recommended.11

    To ensure micronutrient adequacy and minimize the influence of micronutrient differences among test diets, we gave each participant a daily multivitamin and mineral supplement."

    I'm also concerned with the fact that they used a multivitamin, as several vitamins and minerals cancel each other out or enhance each other when presented together, and some of those affect weight loss. For example, calcium should not be taken together with iron, copper, or zinc, but calcium affects weight loss so much that the Mayo suggests taking calcium supplements if you are not a high dairy consumer. If the meals weren't planned carefully, this could also affect results, and since neither the menu nor micronutrient breakdown are available, we don't have much to go on.

    Thanks for the breakdown of each diet.

    My concern on not controlling for protein is that would that not skew the numbers in favor of the diet/groups with the higher protein intake? As protein causes your body to work harder to break foods down and is typically associated with a higher TEF and would also increase TEE...?

    feel free to correct any flaws in my thinking....

    Possibly, but we can do a rough calc on the TEF of the diets:

    TEF
    protein is 20-30%
    fat 2-5%
    carbs 5-10%

    That diet with low carbs and higher protein actually has a lower TEF as its 60% fat.
  • ndj1979
    ndj1979 Posts: 29,136 Member
    Emilia777 wrote: »
    ndj1979 wrote: »
    Thanks for the breakdown of each diet.

    My concern on not controlling for protein is that would that not skew the numbers in favor of the diet/groups with the higher protein intake? As protein causes your body to work harder to break foods down and is typically associated with a higher TEF and would also increase TEE...?

    feel free to correct any flaws in my thinking....

    What I find odd is that they mention this but just dismiss it.
    The thermic effect of food (the increase in energy expenditure arising from digestive and metabolic processes) dissipates in the late postprandial period and would not affect REE measured in the fasting state. Because the thermic effect of food tends to be greater for carbohydrate than fat,24,25 it would also not explain the lower TEE on the low-fat diet. Although protein has a high thermic effect of food,16 the content of this macronutrient was the same for the low-fat and low–glycemic index diets and contributed only 10% more to total energy intake with the very low-carbohydrate diet compared with the other 2 diets.
    ndj1979 wrote: »
    Can I just tell you all, you made my day by analyzing the science. I see it so rarely on these boards. And I have to say, we know it affects CICO, the issue is more of the exactly how's.

    I agree with the others though-the protein should not have been adjusted so greatly, however, the reasoning makes sense. The method's section discusses how each was developed and the reasoning.

    "The run-in diet was consistent with the Acceptable Macronutrient Distribution Range specified by the Institute of Medicine,15 with protein intake at the upper end of the range to enhance satiety during weight loss.16

    The low-fat diet, which had a high glycemic load, was designed to reflect conventional recommendations to reduce dietary fat, emphasize whole grain products, and include a variety of vegetables and fruits.17

    The low–glycemic index diet aimed to achieve a moderate glycemic load by replacing some grain products and starchy vegetables with sources of healthful fat and low–glycemic index vegetables, legumes, and fruits.

    The low-fat and low–glycemic index diets had similar protein and fiber contents.

    The very low-carbohydrate diet was modeled on the Atkins Diet and had a low glycemic load due to more severe restriction of carbohydrate. We provided 3 g of fiber with each meal (Metamucil, Procter & Gamble) during the very low-carbohydrate diet as recommended.11

    To ensure micronutrient adequacy and minimize the influence of micronutrient differences among test diets, we gave each participant a daily multivitamin and mineral supplement."

    I'm also concerned with the fact that they used a multivitamin, as several vitamins and minerals cancel each other out or enhance each other when presented together, and some of those affect weight loss. For example, calcium should not be taken together with iron, copper, or zinc, but calcium affects weight loss so much that the Mayo suggests taking calcium supplements if you are not a high dairy consumer. If the meals weren't planned carefully, this could also affect results, and since neither the menu nor micronutrient breakdown are available, we don't have much to go on.

    Thanks for the breakdown of each diet.

    My concern on not controlling for protein is that would that not skew the numbers in favor of the diet/groups with the higher protein intake? As protein causes your body to work harder to break foods down and is typically associated with a higher TEF and would also increase TEE...?

    feel free to correct any flaws in my thinking....

    Possibly, but we can do a rough calc on the TEF of the diets:

    TEF
    protein is 20-30%
    fat 2-5%
    carbs 5-10%

    That diet with low carbs and higher protein actually has a lower TEF as its 60% fat.

    interesting..

    thanks..

  • EvgeniZyntx
    EvgeniZyntx Posts: 24,208 Member
    Emilia777 wrote: »
    ndj1979 wrote: »
    Thanks for the breakdown of each diet.

    My concern on not controlling for protein is that would that not skew the numbers in favor of the diet/groups with the higher protein intake? As protein causes your body to work harder to break foods down and is typically associated with a higher TEF and would also increase TEE...?

    feel free to correct any flaws in my thinking....

    What I find odd is that they mention this but just dismiss it.
    The thermic effect of food (the increase in energy expenditure arising from digestive and metabolic processes) dissipates in the late postprandial period and would not affect REE measured in the fasting state. Because the thermic effect of food tends to be greater for carbohydrate than fat,24,25 it would also not explain the lower TEE on the low-fat diet. Although protein has a high thermic effect of food,16 the content of this macronutrient was the same for the low-fat and low–glycemic index diets and contributed only 10% more to total energy intake with the very low-carbohydrate diet compared with the other 2 diets.

    Hmm, so 10% more available energy? And ... <looks at graphs> 10% higher TDEE?!

    Homeostasis, anyone?
  • The_Enginerd
    The_Enginerd Posts: 3,982 Member
    Emilia777 wrote: »
    ndj1979 wrote: »
    Thanks for the breakdown of each diet.

    My concern on not controlling for protein is that would that not skew the numbers in favor of the diet/groups with the higher protein intake? As protein causes your body to work harder to break foods down and is typically associated with a higher TEF and would also increase TEE...?

    feel free to correct any flaws in my thinking....

    What I find odd is that they mention this but just dismiss it.
    The thermic effect of food (the increase in energy expenditure arising from digestive and metabolic processes) dissipates in the late postprandial period and would not affect REE measured in the fasting state. Because the thermic effect of food tends to be greater for carbohydrate than fat,24,25 it would also not explain the lower TEE on the low-fat diet. Although protein has a high thermic effect of food,16 the content of this macronutrient was the same for the low-fat and low–glycemic index diets and contributed only 10% more to total energy intake with the very low-carbohydrate diet compared with the other 2 diets.

    Hmm, so 10% more available energy? And ... <looks at graphs> 10% higher TDEE?!

    Homeostasis, anyone?
    Interesting. People tend to have a range (sometimes quite wide) that they maintain at. If they were getting more calories net after accounting for TEF, this may have very well have had an effect on their REE and TEE. It would be interesting to see this accounted for in a follow up or future study, and what effects that would have on the results.
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    edited May 2015
    ndj1979 wrote: »
    Can I just tell you all, you made my day by analyzing the science. I see it so rarely on these boards. And I have to say, we know it affects CICO, the issue is more of the exactly how's.

    I agree with the others though-the protein should not have been adjusted so greatly, however, the reasoning makes sense. The method's section discusses how each was developed and the reasoning.

    "The run-in diet was consistent with the Acceptable Macronutrient Distribution Range specified by the Institute of Medicine,15 with protein intake at the upper end of the range to enhance satiety during weight loss.16

    The low-fat diet, which had a high glycemic load, was designed to reflect conventional recommendations to reduce dietary fat, emphasize whole grain products, and include a variety of vegetables and fruits.17

    The low–glycemic index diet aimed to achieve a moderate glycemic load by replacing some grain products and starchy vegetables with sources of healthful fat and low–glycemic index vegetables, legumes, and fruits.

    The low-fat and low–glycemic index diets had similar protein and fiber contents.

    The very low-carbohydrate diet was modeled on the Atkins Diet and had a low glycemic load due to more severe restriction of carbohydrate. We provided 3 g of fiber with each meal (Metamucil, Procter & Gamble) during the very low-carbohydrate diet as recommended.11

    To ensure micronutrient adequacy and minimize the influence of micronutrient differences among test diets, we gave each participant a daily multivitamin and mineral supplement."

    I'm also concerned with the fact that they used a multivitamin, as several vitamins and minerals cancel each other out or enhance each other when presented together, and some of those affect weight loss. For example, calcium should not be taken together with iron, copper, or zinc, but calcium affects weight loss so much that the Mayo suggests taking calcium supplements if you are not a high dairy consumer. If the meals weren't planned carefully, this could also affect results, and since neither the menu nor micronutrient breakdown are available, we don't have much to go on.

    Thanks for the breakdown of each diet.

    My concern on not controlling for protein is that would that not skew the numbers in favor of the diet/groups with the higher protein intake? As protein causes your body to work harder to break foods down and is typically associated with a higher TEF and would also increase TEE...?

    feel free to correct any flaws in my thinking....

    This plus the concern that estimates of the calorie counts for meat are too high (which might be the same thing, the argument that we can't access all the calories).

    I wonder to what extent that could account for the differences in the numbers.

    Edit: I see the post running the TEF numbers, but I thought the recent discussion of the errors in calorie count for both went beyond that.
  • lindsayk324
    lindsayk324 Posts: 54 Member
    Oh man I love lit review! Nutrition isn't my particular niche but here's my thoughts:

    Methods:
    Right off the bat, oh yikes, n = 21? And their cohort spans ages (from 18 to 40!), races, and genders. They did a whole lot of fancy statistics on the 21 they had to try to correct for all these potentially confounding factors, but I still feel a little skeptical of results when the sample cohort is so limited in size but broad in characteristics. Add in the monetary incentive that the cohort was given ($2500) and the fact that all were obese/overweight, I'm confident in my opinion that any results are certainly not going to be representative of any one particular individual. In fact, these results will apply to individuals that most closely match the average subject in the study, so a 30yo obese black male from Boston:

    sEr30rT.png

    Results:
    In the plot/regression model (figure 3, which is a pretty terrible figure, imo), I believe the claim that the overall trend is "a significant linear trend in mean change from low-fat to low–glycemic index to very low-carbohydrate diets (P.01)" but if you look at individual trends, some go down, some go up, and others remain unchanged. It would have made a much stronger figure to either plot these as a function of energy expenditure vs time, with the different diets in different colors/points, or to at least color each individual so that we can visually see how subjects responded to each diet...
    Table 3, the outcomes summary, again I'm wary of the hormone levels because while they adjusted for gender/age, I'm skeptical with the small sample size. I'd also assume hormones for women might vary significantly from men, and that the hormones for a younger subject are much different from an older.

    Discussion:
    "TEE differed by approximately 300 kcal/d between these 2 diets [v. low carb & low fat], an effect corresponding with the amount of energy typically expended in 1 hour of moderate-intensity physical activity." Ehhhh but given the age/gender/race mix of the study, maybe this conclusion is a little bit of a stretch.

    Limitations:
    The authors admit their own limitations, but I think a big take-home is this: "Main study limitations are the relatively
    short duration of the test diets and the difficulty extrapolating findings from a feeding study to a more natural setting, in which individuals consume self-selected diets."

    Conclusion:
    Their words: "In conclusion, our study demonstrates that commonly consumed diets can affect metabolism and components of the metabolic syndrome in markedly different ways during weightloss maintenance, independent of energy content."
    My words: There is no "best" macro breakdown for weight loss. The diet that works best for you is the diet that works best for you.
  • nopotofgold
    nopotofgold Posts: 164 Member
    I wondered if they increased the protein to keep a fuller feeling since the carb is so low you can't do a lot of fiber and most people feel full longer because of protein and fiber not fat.
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    Just ran across this research thanks to a recent MFP discussion and thought it was worth its own thread.

    http://jama.jamanetwork.com/article.aspx?articleid=1199154

    Conclusion: Among overweight and obese young adults compared with pre–weight-loss energy expenditure, isocaloric feeding following 10% to 15% weight loss resulted in decreases in REE and TEE that were greatest with the low-fat diet, intermediate with the low–glycemic index diet, and least with the very low-carbohydrate diet.

    Interesting. It supports the idea that diet make-up affects CICO.

    This is very interesting and I need to find some time to read it more carefully, but I was wondering if you have any thoughts about the possible explanations. In particular, I'm wondering how it may relate to another study I recall where two groups of women, one insulin resistant and one not, did a low carb and low fat diet, and the IR women did better on the low carb one, whereas the others did better on the other diet.

    I'm not at all a proponent of low fat diets (personally I would find one difficult to stay on just because the food would satisfy me less), but given that overweight and obese populations are more likely to be IR, I'm wondering if there could be a connection to the results here, although I haven't thought it through.

    I'd also be really interested in results over a longer period of time, of course.
  • JPW1990
    JPW1990 Posts: 2,424 Member
    lemurcat12 wrote: »
    Just ran across this research thanks to a recent MFP discussion and thought it was worth its own thread.

    http://jama.jamanetwork.com/article.aspx?articleid=1199154

    Conclusion: Among overweight and obese young adults compared with pre–weight-loss energy expenditure, isocaloric feeding following 10% to 15% weight loss resulted in decreases in REE and TEE that were greatest with the low-fat diet, intermediate with the low–glycemic index diet, and least with the very low-carbohydrate diet.

    Interesting. It supports the idea that diet make-up affects CICO.

    This is very interesting and I need to find some time to read it more carefully, but I was wondering if you have any thoughts about the possible explanations. In particular, I'm wondering how it may relate to another study I recall where two groups of women, one insulin resistant and one not, did a low carb and low fat diet, and the IR women did better on the low carb one, whereas the others did better on the other diet.

    I'm not at all a proponent of low fat diets (personally I would find one difficult to stay on just because the food would satisfy me less), but given that overweight and obese populations are more likely to be IR, I'm wondering if there could be a connection to the results here, although I haven't thought it through.

    I'd also be really interested in results over a longer period of time, of course.

    That's the real problem with a lot of studies that address LC, and reading through this one, it's no exception. The participants did each of the 3 variations for 4 weeks. That's not long enough to provide data that has any relation to how they'd react long term. It even states the meal plans they used were not intended for long-term sustainability. 4 weeks is barely long enough for someone to be LC adapted, and some people take longer. It's like studying the effectiveness of an antibiotic, but only letting the participants take half a course.

    Also, maybe I missed it, but I didn't see where the transition was between each of the 3 plans. It only says they were done in random order. Someone switching directly from LC to HCLF is going to be miserably sick for a few days, and spending a few days in the bathroom would definitely skew the overall results when they only have 28 days to work with.

    It says they screened out people with health conditions, which I assume would include IR, but that only works if they've been diagnosed IR. The LC forums are filled with people who were undiagnosed until after they tried LC, noticed the difference, and specifically asked their doctor to check it after reading others discuss it.

    I don't doubt the premise of the study - anyone interested will find a lifetime's worth of anecdotal evidence just in the keto community alone. I'm just not sure this really demonstrates what they claim it's doing. Someone, somewhere needs to finally do a study that actually lasts longer than it takes someone to become LC adapted, and analyze the data after adaption, not just during.
  • PeachyCarol
    PeachyCarol Posts: 8,029 Member
    If anything, hopefully this study will spur further research of its type. Hopefully with a larger sample size over a longer period of time.
  • EvgeniZyntx
    EvgeniZyntx Posts: 24,208 Member
    lemurcat12 wrote: »
    Just ran across this research thanks to a recent MFP discussion and thought it was worth its own thread.

    http://jama.jamanetwork.com/article.aspx?articleid=1199154

    Conclusion: Among overweight and obese young adults compared with pre–weight-loss energy expenditure, isocaloric feeding following 10% to 15% weight loss resulted in decreases in REE and TEE that were greatest with the low-fat diet, intermediate with the low–glycemic index diet, and least with the very low-carbohydrate diet.

    Interesting. It supports the idea that diet make-up affects CICO.

    This is very interesting and I need to find some time to read it more carefully, but I was wondering if you have any thoughts about the possible explanations.
    Congecture mode on. What follows is guessing - don't put your money on it.

    My first guess would be around the importance of dietary fat for micronutrient transport. Low fat - poor absorption of micronutrients - impacts hormonal activity (adrenogenics), down-regulates thermogensis. Second guess would be free lipids for actual hormone synthesis but that is a little iffy, because the adaptive process first up regulated hormones when we Have low free lipids and then down regulates. How bad can low fat diets be in terms of micronutrient transport - hair loss, amenorrhea, etc are some of the common signs.
    In particular, I'm wondering how it may relate to another study I recall where two groups of women, one insulin resistant and one not, did a low carb and low fat diet, and the IR women did better on the low carb one, whereas the others did better on the other diet.

    By 'did better' I'm assuming lost more. Don't know, I'd need to see the study but there is strong evidence that people with metabolic issues (IR, PCOS, etc) do better with lower carb diets. I don't now if it's because fat isn't sufficient or if we are seeing what the low carb people call "metabolic advantage", satiety factors, positive improvement in the ratio of fat breakdown (lipolysis) vs fat production and storage.

    A primary feature of insulin resistance is an impaired ability of muscle cells to take up circulating glucose. A person with insulin resistance will likely divert a greater amount of dietary carbs to the liver where it is converted to fat instead of being used for energy. In theory. Because I still struggle to believe that in a net deficit those lipids aren't used. But coupled with satiety factors this might make sense.

    I'm not at all a proponent of low fat diets (personally I would find one difficult to stay on just because the food would satisfy me less), but given that overweight and obese populations are more likely to be IR, I'm wondering if there could be a connection to the results here, although I haven't thought it through.

    I'd also be really interested in results over a longer period of time, of course.

    Yeah, I'm very NOT Low-fat.

    Hope that helps.
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    Yes, thanks!
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
    The decrease in TEE, assessed using the doubly-labeled water method, also differed significantly by diet (mean [95% CI], −423 [–606 to –239] kcal/d for low fat; −297 [–479 to –115] kcal/d for low glycemic index; and −97 [–281 to 86] kcal/d for very low carbohydrate...

    Did they account for changes in body composition?