[Grovenet] Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years

Thu Jul 17 19:12:29 PDT 2008

The best book I know of for those with diabetes or pre-diabetes is Dr. Bernstein's Diabetes Solution.  I highly recommend it.

The key factor to keep in mind about the Mediterranean diet is that it includes nine (9) to twelve (12) servings of fruits and vegetables a day, and more vegetables than fruit.

Jane B-P

Here's some important weight-loss and heart health
information for you all, and especially for those of you with diabetes
or pre-diabetes.

bob "eat healthy, baby!!" browning

-----Original Message-----
From: Bob Browning <rab at jurislex.com>
To: Grovenet <grovenet at rdrop.com>
Sent: Thu, 17 Jul 2008 10:11 am
Subject: [Grovenet] Low-carb and Mediterranean diets beat low-fat for weight-loss, lipid changes at two years

Here's some important weight-loss and heart health
information for you all, and especially for those of you with diabetes
or pre-diabetes.

bob "eat healthy, baby!!" browning

*********************************

Low-carb and Mediterranean diets beat
low-fat for weight-loss, lipid changes at two years   July 16, 2008   | Shelley Wood

 Download
slides 

Beer-Sheva, Israel - Both a low-carbohydrate diet or a
Mediterranean-style diet may be "effective alternatives" to a low-fat
diet, with more favorable effects on lipids and/or glycemic control,
new research suggests [1].
The two-year study, which managed to keep almost 85% of the 322 study
participants on one of the three diets for the entire period, offers0Athe hope that weight-loss diets can be tailored to personal
preferences, without sacrificing efficacy, researchers say.

"Several recent one-year dietary studies have led the American
Diabetes Association to state in January 2008 that low-carb diets
should be considered for a maximum of one year," lead author on the
study, Dr Iris Shai (Ben Gurion University of the Negev,
Beer-Sheva, Israel), told heartwire.
"The current two-year study suggests that one low-fat diet doesn't fit
all, meaning that the old paradigm should be reconsidered."

Shai and colleagues publish the results of the Dietary
Intervention Randomized Controlled Trial (DIRECT) in the July 17,
2008 issue of the New England Journal of Medicine.

  Diet options

At the start of the study, DIRECT subjects were middle-aged (mean
age 52 years) and mildly obese (body-mass index=31). All participants
were randomized to one of three diets: low-fat/restricted-calorie diet;
Mediterranean/restricted-calorie diet; or low-carbohydrate diet, with
no restriction on calories. After two years, adherence to their
respective diets ranged from more than 90% in the low-fat group, to 85%
in the Mediterranean diet group, to 78.0% in the low-carb group. 

Weight loss occurred in all three groups over the 24 months but
was
greater in the Mediterranean and low-carb groups. In men—who made up
the bulk of the study cohort—weight loss was greatest in the low-carb
group, whereas women—just 45 in the study cohort—appeared to lose more=0
Aweight on the Mediterranean diet. When the analysis was performed just
in the 272 "completers" who adhered to the diet for the entire study
period, the pattern of weight loss associated with each diet was
similar.

  Weight loss

        Group

        Low-fat (kg)

        Mediterranean (kg)

        Low-carb (kg)

        All patients

-2.9

-4.4

-4.7

        All completers

-3.3

-4.6

-5.5

        Men

-3.4

-4.0

-4.9

  20     

        Women

-0.1

-6.2

-2.4

Changes in lipid parameters were also most striking in the
low-carb
and Mediterranean-diet groups. HDL increases and triglyceride decreases
were most pronounced in the low-carb group, while reductions in LDL
cholesterol were greatest in the Mediterranean-diet group. Reductions
in total cholesterol/HDL ratio were greatest in the low-carb group,
closely followed by the Mediterranean-diet group.

  Lipid changes

        Parameter

        Low-fat (mg/dL)

        Low-carb (mg/dL)

        Mediterranean (mg/dL)

        HDL

+6.4

+8.4

+6.3

=2
0       

        LDL

-0.05

-3.0

-5.6

        Triglycerides

-2.8

-23.7

-21.8

        Total cholesterol/HDL ratio

-0.6

-1.1

-0.9

  To download tables as slides, click on slide logo above

In the subset of patients with diabetes—just 36 out of 322
subjects—the Mediterranean diet appeared to improve fasting plasma
glucose levels. According to Shai, the results suggest that "one size
doesn't fit all." 

"The current results suggest that Mediterranean and
low-carbohydrate
diets are effective alternatives to low-fat diets," she said. "The more
favorable effects on lipids with the low-carbohydrate diet and on
glycemic control with the Mediterranean diet suggest that personal
preferences and metabolic considerations might inform individualized

tailoring of dietary interventions."

  An "optimal" study environment

One of the unique features of the study was its location: the
DIRECT
study was conducted at a nuclear research center in Israel with an
on-site cafeteria and medical clinic. Participants in the trial ate
their main meal of the day—lunch—in the workplace cafeteria, where food
choices were carefully controlled and labeled. On-site dieticians
worked regularly with participants to help them adhere to their diets.
Indeed, the Nuclear Research Center Negev itself, along with the Robert
C and Veronica Atkins Foundation—the low-carb diet in DIRECT was
based on the Atkins diet—helped fund the study.

In the paper, Shai et al acknowledge that the setting was
perfectly
suited to a study of this kind, but that this doesn't mean these diets
would not have worked elsewhere. "We took advantage of the isolated
place, which is highly monitored by an excellent internal medical
department, and a set of cafeterias [whose menus] we could modify," she
told heartwire. And in fact, she said, "we do
believe that this optimal model could be applied in other workplaces,
once the manager prioritizes this kind of long-term health-promotion
project."

Why do they work?

        =2
0   

Asked what she thinks is behind the success of the
low-carb and
Mediterranean diets, Shai said that, at least in the case of the
Mediterranean diet, reducing calories may be slightly easier when
moderate fat consumption is permitted. 

In the case of the low-carb diet, there are a number
of possible explanations, she says.

"First, the advantage of this strategy is that the
'enemy'—carbohydrates—is well defined and once learning it, the
[dieter] knows what to stay away from, without counting calories," Shai
told heartwire. "And after the initiation phase,
the dieter has less craving. Second, we assume that a relatively
high-protein diet does contribute to higher satiety. Third, the
immediate response of the body to weight loss may encourage the dieter."

-SW

Commenting on the study for heartwire, Dr
Eric Westman (Duke
Clinical Research Institute, Durham, NC), a long-time skeptic of
low-fat diets, acknowledged that the low-carb diet craze of the early
21st century has died down, something he can't explain. "There is this
study, and there are two additional National Institutes of Health
studies in the US that are progressing 
well, so I don't know what the
push-back was. Some have speculated that Dr [Robert C] Atkins
dying or the company going bankrupt made the wind change, even though
the science has just marched along. It's a mystery to me."

Like Shai, Westman thinks it might be time to "get beyond that old
low-fat diet" and that, slowly but surely, this is actually starting to
happen.

I'm
reading my daughter's high school health textbook, and
it's like a religion: 'Everyone should follow a low-fat
diet' and 'Saturated fats kill you,'
and that's just wrong, plain wrong.

"I'm reading my daughter's high school health textbook and it's
like
a religion: 'Everyone should follow a low-fat diet' and 'Saturated fats
kill you,' and that's just wrong, plain wrong," he told heartwire.
"There are more people coming out of the closet saying they weren't
part of this low-fat diet thing all along, but I guess they felt they
couldn't speak up. I think that what we're soon going to find is that
nobody's going to be defending the 30% fat, low-fat diet anymore."

Indeed, AHA past-president Dr Robert Eckel
(University
of Colorado Health Sciences Center, Denver), points out that Shai et
al's study used the outdated 2000 AHA guidelines as the template for
its low-fat diet. 

"The AHA updated its dietary guidelines in 2005, which are quite
different from the diet that's quoted here," he told heartwire.
"The dietary fat restriction at 30% of calories is no longer part of
the AHA guide
lines, and the saturated-fat content has been reduced from
10% to 7% and the cholesterol content from 300 to 200 mg/day. I think
it's a little bit unfair to kind of generalize that the AHA, number
one, stands for a low-fat diet; that's no longer the case. And number
two, there is some kind of mysterious benefit of being on the
Mediterranean and low-carb diets over time that doesn't necessarily at
this point have any explanation."

But Eckel rejects the idea that saturated fats could be embraced
by
any legitimate weight-loss approach. "Anything that would endorse the
Atkins-type of food-intake pattern would not be something that the AHA
would back," he said firmly. "Saturated fats raise LDL cholesterol—I
don't think many people would disagree with that. . . . At this point
limiting saturated fats is still a position the AHA would claim, and I
think that's consistent with the National Cholesterol Education
Program guidelines, the American Diabetes Association, the US Department
of Agriculture.
I don't think there is any major professional organization at this
point that's willing to throw in the towel on saturated fats and say
they are unimportant."

Both Westman and Eckel had some niggling questions about Shai et
al's study. Westman pointed out that there were only 10 people in each
diet group with diabetes and as such the effects of the Mediterranean
diet in this group may have been "overstated." It's likely that both
the Mediterranean and low-carb diets are beneficial in diabetics, h
e
says, since both were higher in fat and lower in carbohydrates.

Eckel, for his part, points out that a study cohort that is 86%
male
is unusual in a diet study, which typically enrolls more women. "How
generalizable this study is to women with obesity is not clear to me,"
he said.

He also pointed to the lack of emphasis on physical activity in
the
study—something he believes is key to keeping weight off long term.

  More tools in the trunk

I
don't think there is any major professional organization at this point
that's willing to throw in the towel on saturated fats and say they are
unimportant.

What the authors, as well as Westman and Eckel, agree is on the
notion of different options for different people, with different
medical concerns. Eckel points to the AHA's "No Fad Diet," which offers
three strategies for people to choose from, including a low-carb
option. Westman stresses the need for physicians treating overweight
and obese patients to stop quibbling over diets. "In the end, all of
these lifestyles work," he said. "Low-fat diets work, but the low-carb
and Mediterranean diets are stronger, and that's good because we need
more tools.  All this 'my diet is better than your diet'—we need to get
beyond that. What we really want are the metabolic outcomes, and there
are many ways to go about it."

Westman also points out that a decades-old bias against the
possibility of higher-fat diets having any benefits
 to them has
hampered research. "It's time to study low-fat and high-fat diets with
cardiac end points and genetic markers to tailor diets for cardiac risk
reduction," he says. 

And until that time, Eckel remains unconvinced. "Until we have
studies . . . that show me that heart attacks, cancer, or other
comorbidities of obesity are reduced in terms of hard end points, I'm
not going to be convinced that any diet is better, even though you may
be down a few more kilograms on that one diet," Eckel told heartwire.
"I'm not denying the success of [Shai et al's] study, I'm just saying
that this is more hand-waving with soft outcomes, which really don't
get at the question: can people lose weight for five, 10, 15, and 20
years, and what does that do to risk for heart disease, stroke, and
mortality?"

        The authors disclose having no conflicts of interest.
Westman disclosed receiving unrestricted research funds
from the Atkins Foundation. Eckel disclosed having no
relevant conflicts of interest.

  Source

Shai I, Schwarzfuchs D, Henkin Y, et al.
Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet. N
Engl J Med 2008; 359:229-41.

  Related links

Different metabolic effects observed with traditional
and Atkins-like diets
    20 

[HeartWire > Cardiometabolic risk; Dec 31, 2007]

Low-glycemic-load diet better than low-fat for weight
loss, but just in "high insulin secreters"

[HeartWire > Cardiometabolic risk; May 15, 2007]

Randomized study comparing four popular diets signals
slight edge for Atkins over higher-carb options

[HeartWire > News; Mar 06, 2007]

Retrospective study shows no increased coronary
disease in women eating low-carbohydrate diets over 20 years

[HeartWire > News; Nov 08, 2006]

New AHA diet recommendations also emphasize lifestyle,
but focus is still mostly on trimming the fat

[HeartWire > Cardiometabolic risk; Jun 19, 2006]

Woman admitted to hospital for ketoacidosis after
following Atkins diet

[HeartWire > News; Mar 16, 2006]

Fewer carbs mean fewer calories, improved insulin
sensitivity, and lower triglycerides, new study shows

[HeartWire > Cardiometabolic risk; Mar 14, 2005]

Adherence, not diet type, the key to trimming the fat

[HeartWire > Cardiometabolic risk; Jan 06, 2005]

Diet dilemma: Are cardiologists going loco for
low-carb?

[HeartWire > Features; Feb 24, 2004]

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