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Wednesday, 20 August 2014

Nutritional Studies - LCHF and Others

Just a few interesting studies in regards Atkins/Low fat high carb (LCHF)/Banting/Paleo diets.

Not in the least, a comprehensive list, but ever improving

the truth is out there

1. Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet
link

A phase of maximum weight loss occurred from 1 to 6 months and a maintenance phase from 7 to 24 months. All groups lost weight, but the reductions were greater in the low-carbohydrate and the Mediterranean-diet groups (P<0.001 for the interaction between diet group and time) than in the low-fat group (Figure 2Figure 2 Weight Changes during 2 Years According to Diet Group.). The overall weight changes among the 322 participants at 24 months were −2.9±4.2 kg for the low-fat group, −4.4±6.0 kg for the Mediterranean-diet group, and −4.7±6.5 kg for the low-carbohydrate group.

HDL cholesterol (Figure 3A) increased during the weight-loss and maintenance phases in all groups, with the greatest increase in the low-carbohydrate group (8.4 mg per deciliter [0.22 mmol per liter]

Triglyceride levels (Figure 3B) decreased significantly in the low-carbohydrate group (23.7 mg per deciliter [0.27 mmol per liter],

The level of high-sensitivity C-reactive protein decreased significantly (P<0.05) only in the Mediterranean-diet group (21%) and the low-carbohydrate group (29%)

C-reactive protein (CRP) is a protein found in the blood, the levels of which rise in response to inflammation (i.e. C-reactive protein is an acute-phase protein). LOWER is better



2. Relation Between Blood Glucose and Coronary Mortality Over 33 Years in the Whitehall Study
Link

Glucose intolerance and new diabetes were each associated with older age, degree of obesity, poorer lung function, and higher systolic blood pressure. Prevalent glucose intolerance and diabetes was associated with low employment grade. Glucose intolerance was linked with a higher prevalence of CHD at baseline. Family history of CHD, ascertained in 6,206 participants, was unrelated to glucose tolerance status.


3. Effect of a low-carbohydrate diet on appetite, blood glucose levels, and insulin resistance in obese patients with type 2 diabetes.
Link

In a small group of obese patients with type 2 diabetes, a low-carbohydrate diet followed for 2 weeks resulted in spontaneous reduction in energy intake to a level appropriate to their height; weight loss that was completely accounted for by reduced caloric intake; much improved 24-hour blood glucose profiles, insulin sensitivity, and hemoglobin A1c; and decreased plasma triglyceride and cholesterol levels. The long-term effects of this diet, however, remain uncertain.



4. Effect of 6-month adherence to a very low carbohydrate diet program.
Link

Serum total cholesterol level decreased 11 +/- 26 mg/dL (P = 0.006), low-density lipoprotein cholesterol level decreased 10 +/- 25 mg/dL (P = 0.01), very good triglyceride level decreased 56 +/- 45 mg/dL (P <0.001), very good high-density lipoprotein (HDL) cholesterol level increased 10 +/- 8 mg/dL (P <0.001) very good, and the cholesterol/HDL cholesterol ratio decreased 0.9 +/- 0.6 units (P <0.001) very good. There were no serious adverse effects, but the possibility of adverse effects in the 10 subjects who did not adhere to the program cannot be eliminated.A very low carbohydrate diet program led to sustained weight loss during a 6-month period. very good

5. Effects of low-carbohydrate vs low-fat diets on weight loss and cardiovascular risk factors: a meta-analysis of randomized controlled trials.
link


RESULTS:
Five trials including a total of 447 individuals fulfilled our inclusion criteria. After 6 months, individuals assigned to low-carbohydrate diets had lost more weight than individuals randomized to low-fat diets (weighted mean difference, -3.3 kg; 95% confidence interval [CI], -5.3 to -1.4 kg). This difference was no longer obvious after 12 months (weighted mean difference, -1.0 kg; 95% CI, -3.5 to 1.5 kg). There were no differences in blood pressure.

Triglyceride and high-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-carbohydrate diets (after 6 months, for triglycerides, weighted mean difference, -22.1 mg/dL [-0.25 mmol/L]; 95% CI, -38.1 to -5.3 mg/dL [-0.43 to -0.06 mmol/L]; and for high-density lipoprotein cholesterol, weighted mean difference, 4.6 mg/dL [0.12 mmol/L]; 95% CI, 1.5-8.1 mg/dL [0.04-0.21 mmol/L]),

but total cholesterol and low-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-fat diets (weighted mean difference in low-density lipoprotein cholesterol after 6 months, 5.4 mg/dL [0.14 mmol/L]; 95% CI, 1.2-10.1 mg/dL [0.03-0.26 mmol/L]).


6. Low-carbohydrate nutrition and metabolism
CONCLUSIONS:
We emphasize that strategies based on carbohydrate restriction have continued to fulfill their promise in relation to weight loss and that, contrary to early concerns, they have a generally beneficial effect on most markers of CVD, even in the absence of weight loss. In combination with the intuitive and established efficacy in relation to glycemic control in diabetics, some form of LCD may be the preferred choice for weight reduction as well as for general health 


7. A randomized trial of a low-carbohydrate diet for obesity.
Link

CONCLUSIONS:
The low-carbohydrate diet produced a greater weight loss (absolute difference, approximately 4 percent) than did the conventional diet for the first six months, but the differences were not significant at one year. The low-carbohydrate diet was associated with a greater improvement in some risk factors for coronary heart disease. Adherence was poor and attrition was high in both groups. Longer and larger studies are required to determine the long-term safety and efficacy of low-carbohydrate, high-protein, high-fat diets.

8. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial.

Link

CONCLUSIONS:
In this study, premenopausal overweight and obese women assigned to follow the Atkins diet, which had the lowest carbohydrate intake, lost more weight at 12 months than women assigned to follow the Zone diet, and had experienced comparable or more favorable metabolic effects than those assigned to the Zone, Ornish, or LEARN diets [corrected] While questions remain about long-term effects and mechanisms, a low-carbohydrate, high-protein, high-fat diet may be considered a feasible alternative recommendation for weight loss.

9. High-density lipoprotein cholesterol changes after continuous egg consumption in healthy adults
Link
CONCLUSION:
In the majority of healthy adults, an addition of one egg per day to a normal fat diet could raise HDL-c levels and decreased the ratio of TC toHDL-c. Therefore, egg consumption might benefit blood cholesterol.


10. A Low-Carbohydrate as Compared with a Low-Fat Diet in Severe Obesity
Link


RESULTS
Seventy-nine subjects completed the six-month study. An analysis including all subjects, with the last observation carried forward for those who dropped out, showed that subjects on the low-carbohydrate diet lost more weight than those on the low-fat diet (mean [±SD], –5.8±8.6 kg vs. –1.9±4.2 kg; P=0.002) and had greater decreases in triglyceride levels (mean, –20±43 percent vs. –4±31 percent; P=0.001), irrespective of the use or nonuse of hypoglycemic or lipid-lowering medications. Insulin sensitivity, measured only in subjects without diabetes, also improved more among subjects on the low-carbohydrate diet (6±9 percent vs. –3±8 percent, P=0.01). The amount of weight lost (P<0.001) and assignment to the low-carbohydrate diet (P=0.01) were independent predictors of improvement in triglyceride levels and insulin sensitivity.

CONCLUSIONS
Severely obese subjects with a high prevalence of diabetes or the metabolic syndrome lost more weight during six months on a carbohydrate-restricted diet than on a calorie- and fat-restricted diet, with a relative improvement in insulin sensitivity and triglyceride levels, even after adjustment for the amount of weight lost. This finding should be interpreted with caution, given the small magnitude of overall and between-group differences in weight loss in these markedly obese subjects and the short duration of the study. Future studies evaluating long-term cardiovascular outcomes are needed before a carbohydrate-restricted diet can be endorsed


11. Diets with high or low protein content and glycemic index for weight-loss maintenance

Link
CONCLUSIONS
In this large European study, a modest increase in protein content and a modest reduction in the glycemic index led to an improvement in study completion and maintenance of weight loss. (Funded by the European Commission; ClinicalTrials.gov number, NCT00390637.)


12. The Effects of Low-Carbohydrate versus Conventional Weight Loss Diets in Severely Obese Adults: One-Year Follow-up of a Randomized Trial

Link

CONCLUSIONS:

Participants on a low-carbohydrate diet had more favourable overall outcomes at 1 year than did those on a conventional diet. Weight loss was similar between groups, but effects on atherogenic dyslipidemia and glycaemic control were still more favourable with low-carbohydrate diet after adjustment for differences in weight loss

13. Dietary fats, carbohydrate, and progression of coronary atherosclerosis in postmenopausal women


CONCLUSIONS:
In postmenopausal women with relatively low total fat intake, a greater saturated fat intake is associated with less progression of coronary atherosclerosis, whereas carbohydrate intake is associated with a greater progression.


14. Long Term Effects of a ketogenic diet in obsess subjects with high cholesterol

link

There was a significant change (P < 0.0001) in the lipid profile of the subjects during the entire study period. The level of total cholesterol decreased significantly after week 1 until the end of the study (Fig. 3). HDL-cholesterol increased significantly (Fig. 4), whereas LDL-cholesterol decreased significantly (Fig. 5). The level of triglycerides significantly decreased from the start till the end of the study (Fig. 6). The blood glucose level of males and females decreased significantly (P < 0.0001) from the start until the 56th week


These studies show the beneficial effects of ketogenic diet following its long term administration. It significantly reduces the body weight and body mass index. Furthermore, it decreases the level of triglycerides, and LDL-cholesterol.

The data presented in this study shows that both high and normal cholesterol groups showed reduction of LDL, however, there was no significant alteration between genders. The level of triglycerides significantly reduced after 8 weeks and showed a further gradual decrease in both groups till the end of the year. Similar changes occurred in males and females. Glucose level decreased significantly in both groups in males and females. As there were no significant differences in male and female subjects in all the parameters examined, the data of males and females in each group are pooled and presented together. Administering ketogenic diet for a relatively longer period did not produce any significant side effects in subjects with high level of total cholesterol. Therefore, this study suggests that it is safe to use ketogenic diet for a longer period of time regardless of the total cholesterol level of the subjects.
Other


15.Effects of Low-Carbohydrate and Low-Fat Diets: A Randomized Trial
September 2014

link

Conclusion
The low-carbohydrate diet was more effective for weight loss and cardiovascular risk factor reduction than the low-fat diet. Restricting carbohydrate may be an option for persons seeking to lose weight and reduce cardiovascular risk factors.


OTHERS

Reply to TC Campbel about critique against their study

http://ajcn.nutrition.org/content/71/3/850.full

if you believe protein intake will cause bone loss :

http://ajcn.nutrition.org/content/73/1/5.full?ijkey=4cb6e2c476005c7b83fa6ad532f803db8a3b65ec&keytype2=tf_ipsecsha


And for the Vegetarians


15. Effect of Vegetarian Diet on Homocysteine Levels

http://content.karger.com/ProdukteDB/produkte.asp?doi=57644

Conclusion: Vegetarian subjects presented significantly higher tHcy levels, higher prevalence of hyperhomocysteinemia, and lower serum vitamin B12 levels than controls.

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