CR, low carbohydrate and exercise versus LDL/heart disease

[Guest guest]

Hi All,

In the pdf-available below paper, how does CR/weight loss in addition to reduced

carbohydrate consumption and exercise affect the risks for heart disease?

Let the study results address the question.

Lofgren I, Zern T, Herron K, West K, Sharman MJ, Volek JS, Shachter NS, Koo SI,

Fernandez ML.

Weight loss associated with reduced intake of carbohydrate reduces the

atherogenicity of LDL in premenopausal women.

Metabolism. 2005 Sep;54(9):1133-41.

PMID: 16125523

The effect of a 3-tier intervention including dietary modifications (ie,

moderate

energy restriction, decreased carbohydrate, increased protein), increased

physical

activity, and the use of carnitine as a dietary supplement was evaluated on

plasma

lipids and the atherogenicity of low-density lipoprotein (LDL) particles in a

population of overweight and obese premenopausal (aged 20-45 years) women.

Carnitine

or a placebo (cellulose) was randomly assigned to the participants using a

double-blind design. Carnitine supplementation was postulated to enhance fat

oxidation resulting in lower concentrations of plasma triglycerides. Seventy

women

completed the 10-week protocol, which followed a reduction in their energy

intake by

15% and a macronutrient energy distribution of 30% protein, 30% fat, and 40%

carbohydrate. In addition, subjects increased the number of steps taken per day

by

4500. As no differences were observed between the carnitine and placebo groups

in

all the measured parameters, all subjects were pooled together for statistical

analysis. Participants decreased (P < .01) their caloric intake (between 4132.8

and

7770 kJ) and followed prescribed dietary modifications as assessed by dietary

records. The average number of steps increased from 8950 +/- 3432 to 12764 +/-

4642

(P < .001). Body weight, plasma total cholesterol, LDL cholesterol, and

triglyceride

were decreased by 4.5%, 8.0%, 12.3%, and 19.2% (P < .0001), respectively, after

the

intervention. Likewise, apolipoproteins B and E decreased by 4.5% and 15% (P <

..05)

after 10 weeks. The LDL mean particle size was increased from 26.74 to 26.86 nm

(P <

..01), and the percent of the smaller LDL subfraction (P < .05) was decreased by

26.5% (P < .05) after 10 weeks. In addition, LDL lag time increased by 9.3% (P <

..01), and LDL conjugated diene formation decreased by 23% (P < .01), indicating

that

the susceptibility of LDL to oxidation was decreased after the intervention.

This

study suggests that moderate weight loss (<5% of body weight) associated with

reduced caloric intake, lower dietary carbohydrate, and increased physical

activity

impacts the atherogenicity of LDL.

.... Table 1. An example of a typical menu for the 5880-kJ group provided to the

participants*

..................................

Breakfast Omelet:

½ Cup egg substitute, ¼ cup chopped onion

¼ Cup chopped green pepper, ¼ cup chopped tomato

1 Teaspoon olive oil

Sauté onion, pepper, and tomato in oil. Add egg and let cook

Optional: salt and pepper to taste

Snack 1 Medium slice wheat bread

Lunch Chef salad:

2 Cup chopped lettuce, ¼ cup chopped tomato

¼ Cup chopped green pepper, ¼ cup chopped onion

2 Teaspoon olive oil, 2 teaspoon vinegar

2 Oz deli turkey, 1 oz deli ham

Dessert:

¼ Cup raisins

Snack 1 Oz Provolone cheese, 1 medium apple

Dinner Entrée:

Sauté chicken in oil mixed with BBQ sauce

6 Oz chicken breast, 1 teaspoon olive oil, 2 teaspoon BBQ sauce

1 Cup spinach (sauté or steam)

1 Cup asparagus (sauté or steam)

Snack 1 Oz tortilla chips, 1 tablespoon salsa, ¼ Cup mozzarella cheese

* Ninety percent of the food was provided to the participants except for the

condiments and nonfat milk.

.... Table 2. Changes in BMI, WC, number of steps per day, and percent of energy

from

macronutrients of premenopausal women at baseline and after 10 weeks of

intervention*

.....................................

Baseline 10 wk

......................................

Weight (kg) 79.4±11.1a 75.8±11.4b

BMI (kg/m2) 29.6±3.2a 28.3±3.4b

WC (cm) 90.1±8.0a 84.3±7.8b

Number of steps per day 8950±3432a 12 764±4642b

Carbohydrates (% energy) 50.9±10.1a 42.1±1.2b

Total fat (% energy) 32.7±7.7a 31.8±1.1a

Saturated fat (% energy) 11.0±0.4a 9.7±0.5b

Monosaturated fat (% energy) 12.3±3.2a 13.8±0.7b

Polysaturated fat (% energy) 6.8±1.9a 5.6±0.4b

Protein (% energy) 16.8±3.3a 28.1±1.0b

.......................................

* Values are presented as mean±SD for n = 70 participants. Values in the same

row

with different superscripts are significantly different as determined by paired

t

test (P < .001).

.... Table 3. Plasma TC, LDL-C, HDL-C, TG, and apo B, CI, CIII, and E

concentrations

of premenopausal women at baseline and after 10 weeks of intervention

......................................

Baseline 10 wk P

......................................

TC (mg/dL) 182.8±37.6 168.2±25.8 <.0001

LDL-C (mg/dL) 99.8±25.1 87.5±24.0 <.0001

HDL-C (mg/dL) 61.4±10.8 61.3±12.4 NS

TG (mg/dL) 120.1±64.0 97.1±43.0 <.0001

Apo B (mg/dL) 74.9±15.1 71.8±13.5 <.05

Apo CI (mg/dL) 5.2±2.3 4.5±1.6 <.05

Apo CIII (mg/dL) 18.8±5.1 17.2±4.4 NS

Apo E (mg/dL) 3.5±1.5 3.0±1.1 <.05

.... Table 4. Distribution of cholesterol in LDL subfractions, LDL peak size, and

presence of apo B phenotype in premenopausal women at baseline and after 10

weeks of

intervention a

..........................................

Baseline 10 wk P

...........................................

LDL peak size (nm) 26.74±3.70 26.86±3.60 <.0001

Pattern B (%) 44 31 .06

LDL 1 (mg/dL) 68.0±12.7 62.5±18.7 <.005

LDL 2 (mg/dL) 24.5±8.6 21.0±8.0 <.0001

LDL 3 (mg/dL) 5.3±6.0 3.2±4.7 <.01

LDL 1 (%) 70.5±8.8 72.1±10.4 NS

LDL 2 (%) 24.6±5.7 24.3±7.2 NS

LDL 3 (%) 4.9±4.8 3.6±4.9 <.05

.................................................

Baseline and 10-week values were compared by using paired t test.

a Values are expressed as mean±SD for n = 70 subjects.

.... Table 5. Presentation of models which determined the major changes (CH) in

weight (WT), TG, LDL-C, and in the parameters of LDL oxidation (lag time and

conjugated dienes)

..................................................

Change Model R2 & #946; P

...................................................

CH WT CH carbohydrate 0.072 .268 .033

CH TG 1. CH energies 0.114 .338 .007

2. CH energies and CHWC 0.194 .348 .003

CH LDL-C CH carbohydrates 0.057 .270 .033

CH lag time CH LDL-C 0.142 & #8722;0.377 .005

CH conjugated dienes CH LDL-C 0.157 .396 .003

Al Pater, PhD; email: old542000@...

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