タグ: fasting plasma glucose

Meta-Analysis Comparing Mediterranean to Low-Fat Diets for Modification of Cardiovascular Risk Factors

Meta-Analysis Comparing Mediterranean to Low-Fat Diets for Modification of Cardiovascular Risk Factors

Abstract

Background

Evidence from individual trials comparing Mediterranean to low-fat diets to modify cardiovascular risk factors remains preliminary.

Methods

We systematically searched MEDLINE, EMBASE, Biosis, Web of Science, and the Cochrane Central Register of Controlled Trials from their inception until January 2011, as well as contacted experts in the field, to identify randomized controlled trials comparing Mediterranean to low-fat diets in overweight/obese individuals, with a minimum follow-up of 6 months, reporting intention-to-treat data on cardiovascular risk factors. Two authors independently assessed trial eligibility and quality.

Results

We identified 6 trials, including 2650 individuals (50% women) fulfilling our inclusion criteria. Mean age of enrolled patients ranged from 35 to 68 years, mean body mass index from 29 to 35 kg/m2. After 2 years of follow-up, individuals assigned to a Mediterranean diet had more favorable changes in weighted mean differences of body weight (−2.2 kg; 95% confidence interval [CI], −3.9 to −0.6), body mass index (−0.6 kg/m2; 95% CI, −1 to −0.1), systolic blood pressure (−1.7 mm Hg; 95% CI, −3.3 to −0.05), diastolic blood pressure (−1.5 mm Hg; 95% CI, −2.1 to −0.8), fasting plasma glucose (−3.8 mg/dL, 95% CI, −7 to −0.6), total cholesterol (−7.4 mg/dL; 95% CI, −10.3 to −4.4), and high-sensitivity C-reactive protein (−1.0 mg/L; 95% CI, −1.5 to −0.5). The observed heterogeneity across individual trials could, by and large, be eliminated by restricting analyses to trials with balanced co-interventions or trials with restriction of daily calorie intake in both diet groups.

Conclusion

Mediterranean diets appear to be more effective than low-fat diets in inducing clinically relevant long-term changes in cardiovascular risk factors and inflammatory markers.

Dietary Fiber

DietaryFiber

Many articles have been reported about the relation between insufficient intake of dietary fiber and lifestyle disease, i.e. myocardial infarction, ischemic stroke, cardiovascular disease, diabetes, breast cancer and gastric cancer. Then the target amount has been set. But the reports about the relation between the intake of dietary fiber and colorectal cancer do not match. It’s unclear that which the intake of dietary fiber in daily life has relation with constipation or not.

In the meta-analysis with trial study, negative correlation has been suggested between the intake amount of dietary fiber and blood pressure, LDL cholesterol and fasting plasma glucose.

In 2015 edition, in order to calculate the dietary reference intakes of dietary fiber, they have compromised of ideal value and reality. Based on the National Health and Nutrition Examination Survey in 2010 and 2011, the median is 13.7 g/d. On the other hand, ideal value besed on the pooled analysis is 24 g/d. The intermediate of them is 18.9 g/d. They have extrapolated body surface area from the ratio of reference weight in each the gender and age groups to reference weight in adult and have set the target amount for each gender and age groups. They have not set the additional amount for pregnant and lactation and they have not set the target amount for child between 1 and 5 years old because it’s difficult to quantify the intake. They don’t ensure the effect of dietary fiber by supplements.

\displaystyle 18.9\ \mathrm{(g/d)}\times [\mathrm{Reference\ Weight\ (kg)}/57.8\ \mathrm{(kg)}]^{0.75}
The Dietary Reference Intakes of Dietary Fiber (g/d) (2015 edition)
Gender Male Female
Age Target Amount Target Amount
0-5 M
6-11 M
1-2
3-5
6-7 ≥ 11 ≥ 10
8-9 ≥ 12 ≥ 12
10-11 ≥ 13 ≥ 13
12-14 ≥ 17 ≥ 16
15-17 ≥ 19 ≥ 17
18-29 ≥ 20 ≥ 18
30-49 ≥ 20 ≥ 18
50-69 ≥ 20 ≥ 18
70- ≥ 19 ≥ 17
Pregnant
Lactation

The Dietary reference Intakes of dietary fiber in 2010 edition is based on the article, Dietary Fiber and Risk of Coronary Heart Disease, in which the reduction of the mortality has been suggested in more than 24 g/d intake group and the increase of mortality has been suggested in less than 12 g/d group. They had set the intermediate value, 18 g/d, as reference. In the National Health and Nutrition Examination Survey in 2005 and 2006, the median intake is 12.3-16.3 g/d in adult male and 11.8-16.1 g/d in adult female, respectively. Then it seems to be determined that the ideal value 24 g/d is not practical for most Japanese.

The Dietary Reference Intakes of Dietary Fiber (g/d) (2010 edition)
Gender Male Female
Age Target Amount Target Amount
0-5 M
6-11 M
1-2
3-5
6-7
8-9
10-11
12-14
15-17
18-29 ≥ 19 ≥ 17
30-49 ≥ 19 ≥ 17
50-69 ≥ 19 ≥ 17
70- ≥ 19 ≥ 17
Pregnant
Lactation

References:
The Dietary Reference Intakes for Japanese (2015 edition) Carbohydrate (pdf)
The Dietary Reference Intakes for Japanese (2010 edition) Carbohydrate (pdf)