The FastDay Forum

Thanks to allanr54 on the Really good answers to the skeptics thread for the link to the following paper`s abstract:
http://www.ncbi.nlm.nih.gov/pubmed/23612508

A few comments questions on it,
Firstly, am I being a muppet or is it only possible on pub med to read the abstract? Would like to read the whole paper if anyone can advise?

What do we learn, as 5:2ers from this paper?
ADFing on a high fat diet is more beneficial for weight loss than ADFing on a low fat diet.
LDL (total?) cholesterol reduction was more pronounced for ADF high fat diet folks compared to adf low fat group.
LDL particle size increased in both ADF high and low fat diet groups.
The reduction in proportion (number of?) of small LDL particles was more pronounced in the ADF low fat group.

So for weight loss ADF on high fat diet is better than adf on low fat diet and for improvevement in ldl particle size and distribution it doesn`t matter whether you are on a high fat or low fat diet, both are just as effective.

Maybe these results hold true for 5:2ing as well?

As an aside and to reopen the never ending discussion on cholesterol, I notice this study focuses on LDL particle size and distribution and not the `total chol/hdl` or the `hdl/ldl` ratios that are mentioned on this forum as the best indicators of heart disease.

For more info on the relevance on LDL particle size and distribution in determining risk of heart disease check out the folowing link:
http://eatingacademy.com/nutrition/the-straight-dope-on-cholesterol-part-iv

Pubmed has links in the top right corner to full text sources when they are available - and they are often not free. The relevant journal in this case is at http://www.nature.com/ejcn/index.html which is linked top left.

In this case they've stuck up the abstract sent by the publisher.

The full paper (actually it's a "short communication" is at http://www.nature.com/ejcn/journal/vaop ... 1383a.html which may require an account. I'm going to read it.

I agree that the full spectrum of cholesterol analysis is the best guide, though I'm not convinced it matters a jot, but in practice it's hard enough to get beyond a simple total cholesterol measure to get triglycerides and HDL separately.

This is interesting, but someone on the Facebook group said that for some reason Varady wasn't mentioning the fact the the high fat group also cut carbs, in the summary. So the results could be more to do with carb intake than fat intake? Definitely need to get hold of the whole paper!

This looks to be a follow up / use of the data from the earlier "does ADF work if you have a crap diet on the feed days" paper, where "crap" is referring to the high fat high carb SAD American diet rather than the low fat higher carb diet they're always being told to eat.

This study is the first to show that ADF with a HF background diet (45% fat) elicits the same beneficial effects on LDL particle size as ADF with an LF diet (25% fat). Specifically, the ADF–HF diet was as effective as the ADF–LF intervention at increasing LDL particle size, elevating the proportion of large LDL particles and decreasing the proportion of small LDL particles. HDL particle size and distribution were not affected by either diet.

Macronutrient distributions of the two diets were as follows: ADF–HF (45% fat, 40% carbohydrate and 15% protein), ADF–LF (25% fat, 60% carbohydrate and 15% protein). Fat content of the diets were as follows: ADF–HF (14% saturated fat, 20% monounsaturated fat, 11% polyunsaturated fat and 0% trans fat), and ADF–LF (6% saturated fat, 13% monounsaturated fat, 6% polyunsaturated fat and 0% trans fat).

The ADF-HF groups Total/HDL ratio went from 3.14 to 2.73 and the ADF-LF from 3.33 to 2.70. ie Low risk to can't be bothered plot it on risk charts.

So the cholesterolphobes need no longer be dietary lipophobes. Good.

Obviously we could describe this as a comparison of a lower carb vs a higher carb diet

From a clinical standpoint, these findings suggest that individuals will not need to change the types of foods they eat, only the pattern of food consumption, to experience the cardio-protective benefits of ADF.

Baseline body weight (ADF–HF: 91.5±2.6 kg, ADF–LF: 91.5±2.9 kg), percent body fat (ADF–HF: 48.5±0.9%, ADF–LF: 47.8±1.1%), age (ADF–HF: 42.4±3.0 years, ADF–LF: 43.2±2.3 years) and BMI (ADF–HF: 35.3±0.7 kg/m2, ADF–LF: 35.5±0.7 kg/m2) did not differ between groups. During the weight loss period (weeks 3–10), body weight was reduced (P<0.0001) by 4.3±1.0 kg and 3.7±0.7 kg (4.8±1.1 and 4.2±0.8%), fat mass decreased by (P<0.0001) 5.4±1.5 kg and 4.2±0.6 kg, while fat-free mass remained unchanged (ADF–HF: 1.1±1.3 kg; ADF–LF: 0.5±0.7 kg)

[carorees]

Do we know whether the HF group had lower carbs? Or were their calorie consumptions just higher?

I note that the tc:HDL ratio was not exactly bad to start with though!

Just an aside from a mere mortal.

If LDL cholesterol is the one we want to be (L)ow - that's how I remember it. Could someone explain the significance of the LDL particle size increasing?

[carorees]

The low density particles (LDL) turn into high density particles as their size increases so turn into "good cholesterol" (HDL).

If LDL cholesterol is the one we want to be (L)ow - that's how I remember it. Could someone explain the significance of the LDL particle size increasing?

Within the low density cholesterol you can have bigger fluffy particles or smaller more dense ones, so an increase in LDL particle size means more of the former and less of the latter.

The small dense LDL is supposed to be the most harmful
http://www.johnshopkinshealthalerts.com ... 886-1.html

So an increase in aprticle size within a given amount of LDL means the LDL is less "harmful".

Do we know whether the HF group had lower carbs? Or were their calorie consumptions just higher?

Both groups did 25 / 125% of calculated calorie needs alternate days, single lunch on fasting day, all food provided.

Carbs went from 60 to 40 to allow fat to go 25 to 45

So really, there is no way of knowing if it was the carbs going down or the fat going up.... ?

So really, there is no way of knowing if it was the carbs going down or the fat going up.... ?

No. It was a comparison of two diets with the same protein and calorie intake (so we can say it wasn't either of those) but different carb and fat content.

[carorees]

Perhaps it doesn't matter, thinking about it, because one could say that the high fat/lower carb diet was more effective than the low fat/higher carb diet, so if we were to give advice to someone wanting to know how to improve their cholesterol, we could say, keep carbs down to 40% and fats up to 45% of calories?

I think the authors are saying they are the same, so there's no need to go low fat.

They don't point to statistically significant differences between diets, do they ? all of the p<0.0001 stats are relative to baseline.

In truth, the connection between fat and cholesterol has never been completely watertight. The US scientist who did all of the work (quite weighty) in the 50s and 60s is no longer around. When he demonstrated the correlations they were only calculated one way. To be certain you need to demonstrate that they also work back the way. Unfortunately in his absence, nobody has access to his original data to do this now. At a similar time, an English researcher also demonstrated a link between fructose and cholesterol. I think that these have been demonstrated both ways.
Catscratch - LDL particles are smaller than HDL. This means that they are more likely to get wedged under the edges of cells etc on the walls of arteries and veins or add to any blockages that are starting. If the particles are larger, it makes this less likely to happen.

[carorees]

Isn't there also some link between particle size and deposition on endothelium? Also between particle size/density and which direction the lipids are being transported...(i.e., into/out of fat stores/liver?). It's a while since I was up to date about all this so things have probably moved on (and I've forgotten it)! There's also VLDL and apoB etc to consider