dr.eddiejo The seemingly endless debate on low carb vs low fat caloric restriction diets in the context of weight loss is, in my opinion, fueled by 1. mixed anecdotal claims and arguments, 2. psuedoscience, and 3. mixed emprical evidence. As for the latter, key design and methodological limitations such as small sample sizes, heterogenous subject pools, relatively short term treatment periods, or poorly monitored free-living protocols introduce issues that may certainly confound the interpretation of the data and leave us with no real emprical consensus on the topic. Keep in mind however these limitations are quite understandable given the logistics that go into conducting these types of dietary intervention studies. Recently, one of the most comprehensive studies examining this debate was published in JAMA. This study assessed and compared weight loss, RMR, and other measurements in 609 overweight participants undergoing a lower carb or lower fat caloric restriction diet across a whole year. The retention rate for this study was one of the best I've seen in studies of this size and magnitude. The caloric intake was equivalent between the two groups at 3-month time points and results showed that after a year there were no significant differences in total weight loss, body fat %, or RMR suppression between the two diet interventions. These findings suggest, with decently strong evidence, that caloric deficit via caloric restriction is the main driver of weight loss in overweight individuals. It is my opinion that skewing macronutrient composition, at least for dietary carbohydrate and fat, is more practically relevant and perhaps impactful for those already with "healthy" body weight or body composition who are looking to cut a bit more body fat. Next up: are there genetic predispositions to specific diet responsiveness?

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The seemingly endless debate on low carb vs low fat caloric restriction diets in the context of weight loss is, in my opinion, fueled by 1. mixed anecdotal claims and arguments, 2. psuedoscience, and 3. mixed emprical evidence. As for the latter, key design and methodological limitations such as small sample sizes, heterogenous subject pools, relatively short term treatment periods, or poorly monitored free-living protocols introduce issues that may certainly confound the interpretation of the data and leave us with no real emprical consensus on the topic. Keep in mind however these limitations are quite understandable given the logistics that go into conducting these types of dietary intervention studies. Recently, one of the most comprehensive studies examining this debate was published in JAMA. This study assessed and compared weight loss, RMR, and other measurements in 609 overweight participants undergoing a lower carb or lower fat caloric restriction diet across a whole year. The retention rate for this study was one of the best I've seen in studies of this size and magnitude. The caloric intake was equivalent between the two groups at 3-month time points and results showed that after a year there were no significant differences in total weight loss, body fat %, or RMR suppression between the two diet interventions. These findings suggest, with decently strong evidence, that caloric deficit via caloric restriction is the main driver of weight loss in overweight individuals. It is my opinion that skewing macronutrient composition, at least for dietary carbohydrate and fat, is more practically relevant and perhaps impactful for those already with "healthy" body weight or body composition who are looking to cut a bit more body fat. Next up: are there genetic predispositions to specific diet responsiveness?

Comments (59)

mumtazmaulanahidayat

mumtazmaulanahidayat, 10 months ago

@szotaktme thanks sir for the explanation 🙏

jensendpt

jensendpt, 10 months ago

@co_sell

dr.eddiejo

dr.eddiejo, 10 months ago

@alialperergin no difference between groups as well

z_jepsen

z_jepsen, 10 months ago

@leliicastillo I saw this posted by some one else a few days ago actually. Just re confirms what I always tell people !

alialperergin

alialperergin, 10 months ago

@dr.eddiejo thanks for respond

ccm0123

ccm0123, 10 months ago

S

posteriorchainys

posteriorchainys, 10 months ago

Wooow!

bpakfitness

bpakfitness, 10 months ago

I'd be curious to see what the 3 month rebound was for each group

dr.eddiejo

dr.eddiejo, 10 months ago

@ifbbbenpak definitely. I believe follow up analysis is part of this trial so we should be seeing that published soon.

sal_camacho

sal_camacho, 10 months ago

As long as there's no differentiation between carbs in any form of "diet", I.e. Low carb, high carb, etc. there will not be any differences and a big confounder

sal_camacho

sal_camacho, 10 months ago

@sal_camacho without that differentiation any conclusion is misleading, in my opinion

dr.eddiejo

dr.eddiejo, 10 months ago

Not sure if you read the paper but if you did you can see that they had very strong between group analysis of per gram macro nutrient intake at 3,6,9 and 12 months with at least 200 in each group. Take a look at the p value and 95% confidence intervals and if you know how, calculate the statical power of this analysis as well as the effect sizes. When considering all those statistical factors I would say these two groups underwent differential dietary interventions. Also the point of the study was not to examine and compare extremely discrepant carbs intakes, especially for a year in 600 subjects

layteejayne

layteejayne, 8 months ago

@laytemari

celia.psicofit

celia.psicofit, 8 months ago

We're only men in the sample?

taylor.elze

taylor.elze, 8 months ago

Is there such a thing as carb sensitivity? Like person A should go on a low carb diet because they are more "carb sensitive" than person B. It seems like low carb or keto advocates like to use that term to advocate for a keto diet.

steven_a_tijerina

steven_a_tijerina, 5 months ago

@spydr143 low carb vs low fat

megsmccauley

megsmccauley, 4 months ago

@menandrogelua