New study out of Harvard -- TYPE of calories matters more

Siege_Tank

ETA: loved the article, and love the OP, I just have an issue with ABC "news" if that's what the definition of news is these days.

THIS is why articles like this are dangerous and stupid.

The low-carb diet seemed to help participants burn the most calories. But it also increased certain markers of stress and inflammation in the body, such as the stress hormone cortisol, which are risk factors for cardiovascular disease and other health problems.

In the end, the researchers found that the low-glycemic index diet struck the right balance for the participants. It helped the dieters burn more calories, though not as many as the low-carb diet, but didn't seem to increase disease-causing stress markers in the body.

I wonder by how much a low carb, high protein diet increased those "markers" for stress and inflammation... because I'm willing to bet that you can't raise cortisol by statistically significant amounts by changing the macro ratios of your diet.

If I had to wager, I'd BET that the markers fall within the range of error ratios for cortisol and other "markers" for those 7 out of 21 people who were on the low carb side of the study.

The study did not follow patients for the long term, and the authors note that it's difficult to say whether the dieters would have maintained their weight loss outside of the study's highly controlled setting.

And another thing, taking overweight individuals, and changing up their diets from a calorie cut to a maintenance level - and then studying what these diets did...

WHERE'S the control group? Where's the 7 lean individuals fed this diet, and the 7 overweight individuals who HADN'T just lost 12.5% of their body weight????????????????

Timehope

"The Art & Science of Low Carbohydrate Living" by Volek & Phinney, Ph. Ds, says low-carb IS healthy. Their long-term studies report most people on such a diet drop total cholesterol and fasting blood glucose; triglycerides typically drop by half. LDL usually
goes down a bit, then rises a bit at about the 30-lb. weight loss point -- the body's fat cells apparently release stored LDL fat molecules at that point -- and after a few months the LDL goes down again. Also the ratios of these various blood components approach ideals, and the ratios indicate that LDL particle size shifts to a much healthier range. (Not all LDL is equally bad.)
Inflammation markers also drop. All these are the most-used indicators of the cardiovascular health of a diet.
--
The one marker that is not so positive is cortisol, which tends to go up on a low-carb diet. But it isn't clear if that has any significance.
--
Volek and Phinney argue that it takes four to six weeks for the body to fully adjust to a low-carbohydrate diet; various enzymes have to be constructed to take better advantage of fat in the absence of carbs. Once adapted, the body soon shows the advantages listed above. They say that most of the popularly reported studies such as the one you cite tend to be too short-term
to compare accurately.
--
Also, it is a bit ironic that a slice of whole wheat bread causes a higher rise in blood glucose (a bad thing for those who are insulin resistant) than a piece of candy with the same caloric content.

Acg67

"The Art & Science of Low Carbohydrate Living" by Volek & Phinney, Ph. Ds, says low-carb IS healthy. Their long-term studies report most people on such a diet drop total cholesterol and fasting blood glucose; triglycerides typically drop by half. LDL usually
goes down a bit, then rises a bit at about the 30-lb. weight loss point -- the body's fat cells apparently release stored LDL fat molecules at that point -- and after a few months the LDL goes down again. Also the ratios of these various blood components approach ideals, and the ratios indicate that LDL particle size shifts to a much healthier range. (Not all LDL is equally bad.)
Inflammation markers also drop. All these are the most-used indicators of the cardiovascular health of a diet.
--
The one marker that is not so positive is cortisol, which tends to go up on a low-carb diet. But it isn't clear if that has any significance.
--
Volek and Phinney argue that it takes four to six weeks for the body to fully adjust to a low-carbohydrate diet; various enzymes have to be constructed to take better advantage of fat in the absence of carbs. Once adapted, the body soon shows the advantages listed above. They say that most of the popularly reported studies such as the one you cite tend to be too short-term
to compare accurately.
--
Also, it is a bit ironic that a slice of whole wheat bread causes a higher rise in blood glucose (a bad thing for those who are insulin resistant) than a piece of candy with the same caloric content.

Lol Volek and Phinney, pay attention to study design, results and their conclusions

etoiles_argentees

Siege guy - Oh you know, the outliers always get kicked out of the studies, unfortunately.

Volek and Phinney? Please.

You'd like to talk about cortisol?

Siege_Tank

Lol Volek and Phinney, pay attention to study design, results and their conclusions

Fine, but every study should be reviewed and scrutinized by peers for errors, omissions, and misinformation... and I'd have to contend that ANY information from a study is better than NO data - or parenthetical suppositions or deductions based on logic, intuition, or inference - (which is to say.. guesses without any data behind it)

rm7161

Oh holy mother of God....doesn't it really come down to eat as many clean, whole foods as you can.

No, that's not what the study was about at all. It is called "Effects of Dietary Composition on Energy Expenditure During Weight-Loss Maintenance" and never mentions whole foods at all. If you have metabolic syndrome or something related to it, it might be very interesting for you, as it goes into a lot of detail about markers for that. I learned from reading the fine print that a low glycemic index diet also reduced the amount of TSH excreted, which is a factor for someone with thyroid disorders. (also something I have)

So all in all, if you aren't dealing with high levels of cardiovascular risk or a disease that has high markers of inflammation and is treatable by losing weight, it is probably not that interesting for you.

Siege_Tank

Siege guy - Oh you know, the outliers always get kicked out of the studies, unfortunately.

Volek and Phinney? Please.

You'd like to talk about cortisol?

LOL YES!! the outliers get kicked out of my real estate appraisals too!! But there is always a range in any of the data sets when you compare different individuals, whether it is different individual people or different individual farm land sales..

and I'm betting that compared the the other 14 people in the study, the rise in cortisol was statistical noise, the kind associated with a rise in higher protein assimilation from their higher protein consumption...

ETA: I LOVE any chance I get to use the word assimilate. =D

rm7161

Siege guy - Oh you know, the outliers always get kicked out of the studies, unfortunately.

Volek and Phinney? Please.

You'd like to talk about cortisol?

LOL YES!! the outliers get kicked out of my real estate appraisals too!! But there is always a range in any of the data sets when you compare different individuals, whether it is different individual people or different individual farm land sales..

and I'm betting that compared the the other 14 people in the study, the rise in cortisol was statistical noise, the kind associated with a rise in higher protein assimilation from their higher protein consumption...

you could read it, you know.


Hormones and Components
of the Metabolic Syndrome


Serum leptin was highest with the lowfat
diet (mean [95% CI], 14.9 [12.1-
18.4] ng/mL), intermediate with the
low–glycemic index diet (12.7 [10.3-
15.6] ng/mL), and lowest with the very
low-carbohydrate diet (11.2 [9.1-
13.8] ng/mL; overall P.001)
(Table 3). For the 3 diets, cortisol excretion
measured with a 24-hour urine
collection (mean [95% CI], 50 [41-
60] μg/d for low fat; 60 [49-73] μg/d
for low glycemic index; and 71 [58-
86] μg/d for very low carbohydrate;
overall P=.005) and serum thyroidstimulating
hormone (mean [95% CI],
1.27 [1.01-1.60] μIU/mL for low fat;
1.22 [0.97-1.54] μIU/mL for low glycemic
index; and 1.11 [0.88-1.40]
μIU/mL for very low carbohydrate;
overall P=.04) also differed in a linear
fashion by glycemic load. Serum triiodothyronine
was lower with the very
low-carbohydrate diet compared with
the other 2 diets (mean [95% CI], 121
[108-135] ng/dL for low-fat diet and
123 [110-137 ng/dL for low–glycemic
index diet vs 108 [96-120] ng/dL for
very low-carbohydrate diet; overall
P=.006).
Regarding components of the metabolic
syndrome, indexes of peripheral
(P=.02) and hepatic (P=.03) insulin
sensitivity were lowest with the lowfat
diet. Comparing the low-fat, low–
glycemic index, and very lowcarbohydrate
diets, serum HDL
cholesterol (mean [95% CI], 40 [35-
45] mg/dL; 45 [41-50] mg/dL; and 48
[44-53] mg/dL, respectively; overall
P.001), triglycerides (107 [87-131]
mg/dL; 87 [71-106] mg/dL; and 66 [54-
81] mg/dL, respectively; overall
P.001), and plasminogen activator inhibitor
1 (mean [95% CI], 1.39 [0.94-
2.05] ng/mL; 1.15 [0.78-1.71] ng/mL;
and 1.01 [0.68-1.49] ng/mL, respectively;
P for trend by glycemic load=.04)
were most favorable with the very lowcarbohydrate
diet and least favorable
with the low-fat diet. However, CRP
tended to be higher with the very lowcarbohydrate
diet (median [95% CI],
0.78 [0.38-1.92] mg/L for low-fat diet;
0.76 [0.50-2.20] mg/L for low–
glycemic index diet; and 0.87 [0.57-
2.69] mg/L for very low-carbohydrate
diet; P for trend by glycemic load=.05).
Blood pressure did not differ among the
3 diets.

sdumma

Great info thanks!

Siege_Tank

For the 3 diets, cortisol excretion measured with a 24-hour urine collection (mean [95% CI],

50 [41-60] μg/d for low fat;
60 [49-73] μg/d for low glycemic index;
71 [58-86] μg/d for very low carbohydrate;

overall P=.005)

Thank you so much!! I didn't really care enough to look through the study, but seeing the data set here - it still means NOTHING without a control group... however the differences between 41-60 micrograms (millionths of a gram) to 58-86 micrograms of cortisol fall within the normal range of urinary measured cortisol for human beings, or 11μg to 176μg.

hrubyk1804

Oh holy mother of God....doesn't it really come down to eat as many clean, whole foods as you can.

No, that's not what the study was about at all. It is called "Effects of Dietary Composition on Energy Expenditure During Weight-Loss Maintenance" and never mentions whole foods at all. If you have metabolic syndrome or something related to it, it might be very interesting for you, as it goes into a lot of detail about markers for that. I learned from reading the fine print that a low glycemic index diet also reduced the amount of TSH excreted, which is a factor for someone with thyroid disorders. (also something I have)

So all in all, if you aren't dealing with high levels of cardiovascular risk or a disease that has high markers of inflammation and is treatable by losing weight, it is probably not that interesting for you.

Thank you...I wasn't referring to the study itself.

19kat55

bump

etoiles_argentees

What would you like to know about cortisol? You already know that in the short term it relieves stress and is sensitive to one's psycological state. In addition to being needed for repeated muscle contraction it also redirects glucose to the brain.....breaks down protein into amino acids and so on. And yeah, at too high of a concentration cortisol turns off the release of CRF from the hypothalamus and ACTH from the pituitary and so on. Chronic stress is no good, we know that.

I'm way off topic here, I apologize, back to the study.

Polluxi

Self reported intake based on dietary recall and no where does it show that any of the groups ate in a surplus and lost more weight than subjects eating in a deficit. So once again I think your misremember what you read in the past

I never said it was the same study. I said this one had slightly different conditions, in that the high-fat group was simply not calorie-restricted, rather than deliberately consuming surplus calories. I will try to find the study, it was interesting, and I'll post it on here if I do.
But you realize I was originally making a pretty basic point, right? Not all of the calories that go into your mouth go into building bodily tissues; some macronutrients are not as readily stored as fat. Perhaps you'd like to research this yourself, since you believe my reading comprehension is lacking (which I find funny, since this is at least partially my field -- I'm a biophysicist).

You mean like proteins and carbs? And since this is your field, you'd know ad lib doesn't necessarily mean they eat in a surplus, which is what you stated in your original post. What happened to the surplus cals that the subjects you mentioned were able to lose fat?

Yes, like proteins, carbs and fat. They have different rates of absorption and respond differently to the major hormone controlling fat storage. I can only speculate on what happened to the surplus cals in the study - as it was a population study, it didn't go into mechanisms. But I could guess that, first, the calorie-deficit group had a gradual reduction in metabolism. Second, insulin response is mitigated in the high-fat group. Third, higher protein consumption (I think the figure was ~25% as opposed to the WHO's ~15% recommendation) can increase lean muscle mass, gradually increasing metabolism. Last, some of them can essentially be wasted - only partially digested and used by the body. This can be a larger effect than you think, particularly depending on the combination of foods/quality of foods consumed at each meal. Of course calories have their context...if you go about eating a thousand extra every day, then regardless of the source of those calories, you're going to gain weight. But we're talking about a mere 300 here.

rm7161

Thank you so much!! I didn't really care enough to look through the study, but seeing the data set here - it still means NOTHING without a control group... however the differences between 41-60 micrograms (millionths of a gram) to 58-86 micrograms of cortisol fall within the normal range of urinary measured cortisol for human beings, or 11μg to 176μg.

Yes, its not significant for someone who is healthy. It's interesting for someone who might not be though. It may be useful information for someone who is dealing with metabolic disorders, which is why I provided that big clue in the title of the passage. It needs more work, I agree. I don't think it is particularly useful to someone who has 20 lbs to lose.

darlilama

I don't eat "clean", low-fat, low-carb, or low-glycemic, at least not by intention. I try to eat a reasonable diet. On occasion, by golly, I eat fast food... although I'm sort of picky about it. And while most of the time I eat whole grain (because I LIKE them), I also eat white rice and mashed potatoes if I feel like it. Sometimes I make my lunch and sometimes I have a Lean Cuisine. I also exercise vigorously and consistently, although I'm certainly not an athlete. I just do my best to keep it all in balance and not make myself miserable trying to do so.

For the first year I joined MFP, my macro ratios were 60C 15P 25F. (Currently, I'm doing 50C 25P 25F.)

Year 1 results:
lost 30+ lbs
Blood sugar down 12%
Triglycerides down 59%
LDL down 28%
HDL up 14%!

My point is... if you feel and are healthy, does all the nit-picky science really matter? Don't get me wrong. I love science. It's amazing. But, it's the big picture that motivate me!

etoiles_argentees

For the 3 diets, cortisol excretion
measured with a 24-hour urine
collection (mean [95% CI], 50 [41-
60] μg/d for low fat; 60 [49-73] μg/d
for low glycemic index; and 71 [58-
86] μg/d for very low carbohydrate;
overall P=.005)

Well, when mine was studied I didn't fit. It also didn't rise and fall at the predicted times. Out of the study! I guess I'm a snowflake.

etoiles_argentees

I don't eat "clean", low-fat, low-carb, or low-glycemic, at least not by intention. I try to eat a reasonable diet. On occasion, by golly, I eat fast food... although I'm sort of picky about it. And while most of the time I eat whole grain (because I LIKE them), I also eat white rice and mashed potatoes if I feel like it. Sometimes I make my lunch and sometimes I have a Lean Cuisine. I also exercise vigorously and consistently, although I'm certainly not an athlete. I just do my best to keep it all in balance and not make myself miserable trying to do so.

For the first year I joined MFP, my macro ratios were 60C 15P 25F. (Currently, I'm doing 50C 25P 25F.)

Year 1 results:
lost 30+ lbs
Blood sugar down 12%
Triglycerides down 59%
LDL down 28%
HDL up 14%!

My point is... if you feel and are healthy, does all the nit-picky science really matter? Don't get me wrong. I love science. It's amazing. But, it's the big picture that motivate me!

Nice! Sometimes people miss this. Eat less and move more.

rm7161

My point is... if you feel and are healthy, does all the nit-picky science really matter? Don't get me wrong. I love science. It's amazing. But, it's the big picture that motivate me!

No it doesn't... but to be fair, the study wasn't trying to help healthy people either. It was trying to help overweight and obese people who fail at maintaining their weight loss.

In their words, To examine the effects of 3 diets differing widely in macronutrient composition and glycemic load on energy expenditure following weight loss.

Incidentally, this is the reason they were measuring leptin.

etoiles_argentees

following weight loss?

when you are not overweight the calories don't matter, what with the leptin now?
It's very small overall. Forget leptin, please......