Eggs and low carbohydrate diets

[Sherrie]

I have noticed a few concerns about eggs lately, I came across a couple of studies this year addressing the consumption of eggs on a carbohydrate restricted diet:



Dietary Cholesterol from Eggs Increases Plasma HDL Cholesterol in Overweight Men Consuming a Carbohydrate-Restricted Diet1,2
Gisella Mutungi3, Joseph Ratliff3, Michael Puglisi3, Moises Torres-Gonzalez3, Ushma Vaishnav3, Jose O. Leite3, Erin Quann4, Jeff S. Volek4 and Maria Luz Fernandez3,*

3 Department of Nutritional Sciences and 4 Department of Kinesiology, University of Connecticut, Storrs, CT 06269

* To whom correspondence should be addressed. E-mail: maria-luz.fernandez{at}uconn.edu.

Abstract:

Carbohydrate-restricted diets (CRD) significantly decrease body weight and independently improve plasma triglycerides (TG) and HDL cholesterol (HDL-C). Increasing intake of dietary cholesterol from eggs in the context of a low-fat diet maintains the LDL cholesterol (LDL-C)/HDL-C for both hyper- and hypo-responders to dietary cholesterol. In this study, 28 overweight/obese male subjects (BMI = 25–37 kg/m2) aged 40–70 y were recruited to evaluate the contribution of dietary cholesterol from eggs in a CRD. Subjects were counseled to consume a CRD (10–15% energy from carbohydrate) and they were randomly allocated to the EGG group [intake of 3 eggs per day (640 mg/d additional dietary cholesterol)] or SUB group [equivalent amount of egg substitute (0 dietary cholesterol) per day]. Energy intake decreased in both groups from 10,243 ± 4040 to 7968 ± 2401 kJ (P < 0.05) compared with baseline. All subjects irrespective of their assigned group had reduced body weight and waist circumference (P < 0.0001). Similarly, the plasma TG concentration was reduced from 1.34 ± 0.66 to 0.83 ± 0.30 mmol/L after 12 wk (P < 0.001) in all subjects. The plasma LDL-C concentration, as well as the LDL-C:HDL-C ratio, did not change during the intervention. In contrast, plasma HDL-C concentration increased in the EGG group from 1.23 ± 0.39 to 1.47 ± 0.38 mmol/L (P < 0.01), whereas HDL-C did not change in the SUB group. Plasma glucose concentrations in fasting subjects did not change. Eighteen subjects were classified as having the metabolic syndrome (MetS) at the beginning of the study, whereas 3 subjects had that classification at the end. These results suggest that including eggs in a CRD results in increased HDL-C while decreasing the risk factors associated with MetS.

http://jn.nutrition.org/cgi/content/abstract/138/2/272

[Sherrie]

And then this one which you can see in full:

Eggs modulate the inflammatory response to carbohydrate restricted diets in overweight men

Joseph C Ratliff, Gisella Mutungi, Michael J Puglisi, Jeff S Volek and Maria Luz Fernandez

Abstract

Background

Carbohydrate restricted diets (CRD) consistently lower glucose and insulin levels and improve atherogenic dyslipidemia [decreasing triglycerides and increasing HDL cholesterol (HDL-C)]. We have previously shown that male subjects following a CRD experienced significant increases in HDL-C only if they were consuming a higher intake of cholesterol provided by eggs compared to those individuals who were taking lower concentrations of dietary cholesterol. Here, as a follow up of our previous study, we examined the effects of eggs (a source of both dietary cholesterol and lutein) on adiponectin, a marker of insulin sensitivity, and on inflammatory markers in the context of a CRD.

Methods

Twenty eight overweight men [body mass index (BMI) 26–37 kg/m2] aged 40–70 y consumed an ad libitum CRD (% energy from CHOprotein = 17:57:26) for 12 wk. Subjects were matched by age and BMI and randomly assigned to consume eggs (EGG, n = 15) (640 mg additional cholesterol/day provided by eggs) or placebo (SUB, n = 13) (no additional dietary cholesterol). Fasting blood samples were drawn before and after the intervention to assess plasma lipids, insulin, adiponectin and markers of inflammation including C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1(VCAM-1).

Results

Body weight, percent total body fat and trunk fat were reduced for all subjects after 12 wk (P < 0.0001). Increases in adiponectin were also observed (P < 0.01). Subjects in the EGG group had a 21% increase in this adipokine compared to a 7% increase in the SUB group (P < 0.05). Plasma CRP was significantly decreased only in the EGG group (P < 0.05). MCP-1 levels were decreased for the SUB group (P < 0.001), but unchanged in the EGG group. VCAM-1, ICAM-1, TNF-α, and IL-8 were not modified by CRD or eggs.

Conclusion

A CRD with daily intake of eggs decreased plasma CRP and increased plasma adiponectin compared to a CRD without eggs. These findings indicate that eggs make a significant contribution to the anti-inflammatory effects of CRD, possibly due to the presence of cholesterol, which increases HDL-C and to the antioxidant lutein which modulates certain inflammatory responses.

Full text: http://www.nutritionandmetabolism.com/content/5/1/6

[Malcolm]

Far too lazy to check, but is this the same study published in two different places? And did they find anything special about egg cholesterol? - were the non egg group standardised as to the dietary cholesterol they got from other sources?? Inquiring non egg eating minds want to know!!

[Sherrie]

Malcolm I think the first paragraph in the second study answers your questions

Background

Carbohydrate restricted diets (CRD) consistently lower glucose and insulin levels and improve atherogenic dyslipidemia [decreasing triglycerides and increasing HDL cholesterol (HDL-C)]. We have previously shown that male subjects following a CRD experienced significant increases in HDL-C only if they were consuming a higher intake of cholesterol provided by eggs compared to those individuals who were taking lower concentrations of dietary cholesterol. Here, as a follow up of our previous study, we examined the effects of eggs (a source of both dietary cholesterol and lutein) on adiponectin, a marker of insulin sensitivity, and on inflammatory markers in the context of a CRD.

It seems to me the second study is a follow up study from the first to measure other markers and by that paragraph it would seem to me the other group were consuming less dietary cholesterol rather then the same amount from a different source.

In the first study in which I assume the second one is a follow up of due to having most of the same authors they state in the abstract:

Subjects were counseled to consume a CRD (10–15% energy from carbohydrate) and they were randomly allocated to the EGG group [intake of 3 eggs per day (640 mg/d additional dietary cholesterol)] or SUB group [equivalent amount of egg substitute (0 dietary cholesterol) per day].

So rather then compare different dietary cholesterol sources they are instead comparing eating a set amount of dietary cholesterol on a low carb diet in which they use 3 eggs per day to none (aka egg replacements).

[Malcolm]

In which case they haven't even investigated whether there is anything special about egg cholesterol ... well of course apart from it's Alraldite properties that is. - did they test that??

[Sherrie]

Malcolm I think they are more likely to be trying to address the fear of eating eggs on a low carbohydrate diet. I have seen this asked quite a few times just this year alone so at any rate very useful

[Malcolm]

Well you might point out that eggs now even get the Heart Foundation tick of approval for what that is worth - although I guess it is idiots like them that started the whole dietary cholesterol furphy in the first place.

Reminds me of their ad - about their approval being the only endorsement you can't pay to receive .... total bollucks of course - you certainly won't get it unless you do pay them!!

[Sherrie]

Hypocrisy at it's best!