A Pilot Study of a Low-Carbohydrate, Ketogenic Diet for Obesity-Related Polycystic Ovary Syndrome

Reference:
Westman, E.C., Yancy, W.S., Hepburn, J., et al., "A Pilot Study of a Low-Carbohydrate, Ketogenic Diet for Obesity-Related Polycystic Ovary Syndrome," Journal of General Internal Medicine, 19(1S), 2004, page 111.

Summary:

The following information was not written by Atkins professionals.

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age, and is frequently associated with central obesity, insulin resistance, and dyslipidemia. Because recent evidence demonstrates that a low carbohydrate ketogenic diet (LCKD) leads to weight loss and improvements in insulin sensitivity, we conducted this uncontrolled trial of the diet for PCOS.

METHODS: Subjects were recruited from the community. Inclusion criteria were signs or symptoms suggestive of PCOS (chronic anovulation, hyperandrogenemia, hirsuitism), age 18–45 years, body mass index >27 kg/m2, and motivation to lose weight. Subjects received LCKD counseling, with an initial goal of <20 grams of carbohydrate per day, gradually increased as tolerated. Subjects were instructed to take a multivitamin and to drink 6–8 glasses of water daily. Fasting blood samples were obtained at weeks 0, 10 and 24.

RESULTS: Eleven women were enrolled; 5 (45%) completed the 24-week study. In the 5 adherent subjects, there were significant reductions from baseline to 24 weeks in body weight (101.5 to 89.2 kg, P = .01) and percent free testosterone (2.2 to 1.7%, P = .04). There were non-significant changes in insulin (23.7 to 8.2 mg/dl), glucose (97.4 to 79.2 mg/dl), testosterone (51.8 to 48.0 mg/dl), hgbA1c (6.0 to 5.4%), perceived body hair (3.8 to 2.4 on a 7-point scale), LDL (120.0 to 131.8 mg/dl), and triglycerides (101.8 to 73.2 mg/dl). Two women who had previous difficulty becoming pregnant, became pregnant during the study.

CONCLUSION: In women with obesity and a clinical diagnosis of PCOS, a LCKD led to weight loss and a reduction in percent free testosterone over a 24-week period in those able to adhere to the diet. Further controlled studies are needed to determine whether this approach is superior to other weight loss methods for the treatment of PCOS.

Commentary:

The following information was written by Atkins professionals.

Polycystic ovary syndrome (PCOS), an endocrine disorder characterized by central obesity, insulin resistance, and abnormal blood lipid levels, is common in women of reproductive age. Researchers studied the effects of a low carbohydrate ketogenic diet (LCKD) on PCOS. Women between the ages of 18-45 with PCOS were counseled to follow Induction (less than 20 grams of carbohydrate per day) and proceed onto On-Going Weight Loss (increasing carbohydrates as tolerated). They were also instructed to take a multivitamin and consume 6-8 glasses of water a day. After 24 weeks, the five women who completed the study (45% retention) lost a significant amount of weight (average loss of 27 pounds) and percent free testosterone decreased. Although not significant, there were improvements in insulin, glucose, testosterone, HbA1c, perceived body hair, and triglycerides. These results indicate that a LCKD may be beneficial for women with PCOS who are motivated to adhere to the diet.

A Low-Carbohydrate, Ketogenic Diet for Type 2 Diabetes Mellitus

Reference:
Yancy, W.S., Foy, M.E., Westman, E.C., "A Low-Carbohydrate, Ketogenic Diet for Type 2 Diabetes Mellitus," Journal of General Internal Medicine, 19(1S), 2004, page 110.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

Background: Low-carbohydrate diets lead to weight loss, and in one study led to improved glycemic control in diabetics. The objective of this pilot study was to examine the safety and effectiveness for glycemic control of the low-carbohydrate, ketogenic diet (LCKD) in patients with type 2 diabetes.

Methods:In a Veterans’ Affairs Medical Center outpatient clinic, we recruited overweight (body mass index [BMI] >25 kg/m2) subjects taking oral hypoglycemic agents and/or insulin, or having a hemoglobin A1c >6.0% without medication. Subjects received LCKD counseling, with an initial goal of <20 g carbohydrate/day, and were encouraged to take a multivitamin and drink 6-8 glasses of fluids daily. Diabetes medication dosages were reduced by approximately 50% at diet initiation; diuretic medications were reduced by 50% or discontinued, and subsequently reinstituted if needed. Subjects returned every other week for 16 weeks for body and vital sign measurements, counseling, and further medication adjustment if needed. Fasting blood and 24-hour urine tests were obtained at weeks 0, 8, and 16. Serum electrolytes and kidney function tests were monitored additionally at weeks 2 and 12.

Results: Nineteen of the 25 subjects who were enrolled completed the study. Eighteen subjects were men; 13 were White, 5 were Black. The mean [+ SD] age was 56 ± 8 years; mean BMI was 39 ± 6 kg/m2 (range 28-51 kg/m2). From baseline to week 16, hemoglobin A1c decreased by 15% from 7.4 ± 1.5% to 6.3 ± 1.1% (p<0.001) while diabetes medications were discontinued in 6 subjects, reduced in 7 subjects, and unchanged in 5 subjects. Mean body weight decreased by 7% from 131 ± 19 kg to 122 ± 20 kg (p<0.001). Fasting serum glucose decreased from 163 ± 70 mg/dL to 136 ± 48 mg/dL (p=0.05) and triglycerides from 242 ± 268 mg/dL to 144 ± 124 mg/dL (p=0.005). Changes in other serum lipid measurements were not statistically significant. One hypoglycemic attack requiring assistance occurred during the study. In linear regression analyses, weight change at 16 weeks did not predict change in hemoglobin A1c.

 Conclusion:The LCKD reduced glycemia, body weight and serum triglycerides in type 2 diabetic patients but close medical supervision was required to adjust diabetic and blood pressure medications. Controlled trials are needed to determine the safety and effectiveness of this diet compared with conventional weight loss diets.

Commentary:

The following information was written by Atkins professionals.

The safety and effectiveness of a low-carbohydrate, ketogenic diet (LCKD) on improving glycemic control was examined in patients with type 2 diabetes. Participants were counseled to follow Induction (less than 20 grams of carbohydrate per day) and proceed to On-Going Weight Loss (increasing carbohydrate as tolerated). They were also instructed to take a multivitamin and consume 6-8 glasses of fluids daily. After 16 weeks, the 19 men and women completing the study had significant improvements in glycemic control (HbA1c decreased 15%) and triglyceride levels, a significant weight loss of 7%, and improvements in fasting serum glucose. Diabetes medications were discontinued or reduced in 13 of the participants. Results indicate that type 2 diabetics may benefit from a LCKD, as body weight and triglycerides were reduced, and improved glycemic control enabled participants to use less medication. It is important to note that close medical supervision was provided to ensure medications were adjusted appropriately.

More Fat and Fewer Seizures: Dietary Therapies for Epilepsy

Reference:
Kossoff, E.H., "More Fat and Fewer Seizures: Dietary Therapies for Epilepsy," Lancet Neurol, 3(7), 2004, pages 415-420.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

The ketogenic diet is a high-fat, adequate protein, low carbohydrate diet that has been used for the treatment of intractable childhood epilepsy since the 1920s. The diet mimics the biochemical changes associated with starvation, which create ketosis. Although less commonly used in later decades because of the increased availability of anticonvulsants, the ketogenic diet has re-emerged as a therapeutic option. Only a decade ago the ketogenic diet was seen as a last resort; however, it has become more commonly used in academic centres throughout the world even early in the course of epilepsy. The Atkins diet is a recently used, less restrictive, therapy that also creates ketosis and can lower the number of seizures. Dietary therapies may become even more valuable in the therapy of epilepsy when the mechanisms underlying their success are understood.

Comparison of a Low-Fat Diet to a Low-Carbohydrate Diet on Weight Loss, Body Composition, and Risk Factors for Diabetes and Cardiovascular Disease in Overweight Men and Women

Reference:
Meckling, K.A., O'Sullivan, C., Saari, D., "Comparison of a low-fat diet to a low-carbohydrate diet on weight loss, body composition, and risk factors for diabetes and cardiovascular disease in free-living, overweight men and women", Journal of Clinical Endocrinology and Metabolism, 89(6), 2004,  pages:2717-2723.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

Overweight and obese men and women (24-61 yr of age) were recruited into a randomized trial to compare the effects of a low-fat (LF) vs. a low-carbohydrate (LC) diet on weight loss. Thirty-one subjects completed all 10 wk of the diet intervention (retention, 78%). Subjects on the LF diet consumed an average of 17.8% of energy from fat, compared with their habitual intake of 36.4%, and had a resulting energy restriction of 2540 kJ/d. Subjects on the LC diet consumed an average of 15.4% carbohydrate, compared with habitual intakes of about 50% carbohydrate, and had a resulting energy restriction of 3195 kJ/d. Both groups of subjects had significant weight loss over the 10 wk of diet intervention and nearly identical improvements in body weight and fat mass. LF subjects lost an average of 6.8 kg and had a decrease in body mass index of 2.2 kg/m(2), compared with a loss of 7.0 kg and decrease in body mass index of 2.1 kg/m(2) in the LC subjects. The LF group better preserved lean body mass when compared with the LC group; however, only the LC group had a significant decrease in circulating insulin concentrations. Group results indicated that the diets were equally effective in reducing systolic blood pressure by about 10 mm Hg and diastolic pressure by 5 mm Hg and decreasing plasminogen activator inhibitor-1 bioactivity. Blood beta-hydroxybutyrate concentrations were increased in the LC only, at the 2- and 4-wk time points. These data suggest that energy restriction achieved by a very LC diet is equally effective as a LF diet strategy for weight loss and decreasing body fat in overweight and obese adults.

Commentary:

The following information was written by Atkins professionals.

Overweight men and women consuming a low carbohydrate diet (average of 59 grams per day) had similar decreases in weight, blood pressure, and triglyceride levels compared to a group following a low fat, calorie restricted diet. After 10 weeks, only the low fat group had improvements in total and LDL cholesterol. However, they also had an unfavorable decrease in HDL, while HDL increased on the low carbohydrate diet. Fasting insulin significantly decreased only on the low carbohydrate diet. Results indicate that both diets may be effective for promoting short-term weight loss and improving risk factors for cardiovascular disease, although a low carbohydrate diet may be more favorable if improving insulin sensitivity is the main goal.

Obesity and the Metabolic Syndrome in Children and Adolescents

Reference:
Weiss, R., Dziura, J., Burgert, T.S., et al., "Obesity and the Metabolic Syndrome in Children and Adolescents," New England Journal of Medicine, 350(23), 2004, pages 2362-2374.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

BACKGROUND: The prevalence and magnitude of childhood obesity are increasing dramatically. We examined the effect of varying degrees of obesity on the prevalence of the metabolic syndrome and its relation to insulin resistance and to C-reactive protein and adiponectin levels in a large, multiethnic, multiracial cohort of children and adolescents.

METHODS: We administered a standard glucose-tolerance test to 439 obese, 31 overweight, and 20 nonobese children and adolescents. Baseline measurements included blood pressure and plasma lipid, C-reactive protein, and adiponectin levels. Levels of triglycerides, high-density lipoprotein cholesterol, and blood pressure were adjusted for age and sex. Because the body-mass index varies according to age, we standardized the value for age and sex with the use of conversion to a z score.

RESULTS: The prevalence of the metabolic syndrome increased with the severity of obesity and reached 50 percent in severely obese youngsters. Each half-unit increase in the body-mass index, converted to a z score, was associated with an increase in the risk of the metabolic syndrome among overweight and obese subjects (odds ratio, 1.55; 95 percent confidence interval, 1.16 to 2.08), as was each unit of increase in insulin resistance as assessed with the homeostatic model (odds ratio, 1.12; 95 percent confidence interval, 1.07 to 1.18 for each additional unit of insulin resistance). The prevalence of the metabolic syndrome increased significantly with increasing insulin resistance (P for trend, <0.001) after adjustment for race or ethnic group and the degree of obesity. C-reactive protein levels increased and adiponectin levels decreased with increasing obesity.

CONCLUSIONS: The prevalence of the metabolic syndrome is high among obese children and adolescents, and it increases with worsening obesity. Biomarkers of an increased risk of adverse cardiovascular outcomes are already present in these youngsters.

Effects of the Atkins Diet in Type 2 Diabetes

Reference:
Boden, G., Sargrad, K., Homoko, C., et al., "Effects of the Atkins Diet in Type 2 Diabetes: Metabolic Balance Studies," 64th session of the American Diabetes Association, #321-OR, June 8, 2004.

Summary:

The following information was written by Atkins professionals.

Ten obese volunteers with diabetes followed the Induction phase of the Atkins diet (21 grams of carbohydrates). After 2 weeks, results showed an almost 1000 calorie decrease in total calories (3111 calories down to 2181 calories) and a 5.25 pound weight loss that was attributed predominantly to fat, not water. Fasting blood sugar dropped from 135 to113mg/dl, A1c decreased from 7.5% to 6.8%, and there were significant reductions in blood glucose, insulin, triglyceride (158 to102mg/dl), cholesterol (181 to164 mg/dl) and leptin levels. Insulin sensitivity improved by approximately seventy percent. The authors of this ADA funded study concluded, “short-term use of the Atkins diet in patients with type 2 diabetes caused weight loss due mainly to reduced caloric intake, improved insulin sensitivity and glycemic control and reduced plasma cholesterol and triglyceride levels.”

Commentary:

The following information was written by Atkins professionals.

Ten obese men and women with type 2 diabetes were instructed to follow Induction for two weeks. Induction led to weight loss that was predominantly fat loss, with additional improvements in blood sugar control, triglycerides, and cholesterol. Short-term use of Induction was effective in helping manage type 2 diabetes in these obese individuals.

Atkins Diet on Weight Loss and Glucose Metabolism in Obese Patients with Type 2 Diabetes

Reference:
Goldstein, T., Kark, J.D., Berry, E.M., et al., "Influence of a Modified Atkins Diet on Weight Loss and Glucose Metabolism in Obese Type 2 Diabetic Patients,"  The Israel Medical Association Journal, 6, 2004, page 314.

Summary:

The following information was written by Atkins professionals.

Fifty-two volunteers were placed on either the Atkins diet without caloric restriction (25g for the initial 6 weeks and up to 40 grams for another 6 weeks) or a standard calorie restricted (1500 calories for men, 1200 calories for women) ADA diet (45% carbohydrates, 35% fat, 20% protein) for 3 months to compare the effects on weight loss glucose metabolism, and markers of cardiovascular disease risk and kidney function in obese type 2 diabetics. Both groups lost weight and decreased A1c values. The average weight loss on Atkins was 10 pounds with a 1.3% drop in A1c vs. those who followed the ADA diet who lost an average of 8.8 pounds and lowered A1c by .9%. More participants were able to decrease medications while following the Atkins diet, 17 out of 26 as compared with 11 out of 26 in the ADA group. There was a significant decrease in triglycerides by those who followed Atkins that did not occur in the ADA group. Measures in kidney function, blood pressure and uric acid were unchanged. The authors concluded that there were no significant differences between the two dietary approaches for weight and blood sugar management but emphasized that results were slightly in favor of the Atkins diet. In addition, they noted there was no evidence of deleterious effects on heart or kidney function for those in either group. “Based on our results, some patients who are unable to adhere to the ADA diet might find the Atkins diet useful for a short period.”

Commentary:

The following information was written by Atkins professionals.

Obese individuals with type 2 diabetes were instructed to follow either a low carb diet or a calorie restricted diet for three months. Individuals adhering to Induction and OWL for 3 months tended to have a greater weight loss and a greater improvement in blood sugar control than individuals counseled to consume the calorie restricted diet. No harmful effects on kidney and heart function occurred after following either diet. The researchers suggested that Atkins appeared to be easier to adhere to in the short term, increasing compliance and producing maximal benefits for diabetics.

Ketogenic Diet, Brain Glutamate Metabolism and Seizure Control

Reference:
Yudkoff, M., Daikhin, Y., Nissim, I., et al., "Ketogenic Diet, Brain Glutamate Metabolism and Seizure Control",  Prostaglandins, Leukotrienes and Essential Fatty Acids, 70(3), 2004, pages 277-285.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

We do not know the mode of action of the ketogenic diet in controlling epilepsy. One possibility is that the diet alters brain handling of glutamate, the major excitatory neurotransmitter and a probable factor in evoking and perpetuating a convulsion. We have found that brain metabolism of ketone bodies can furnish as much as 30% of glutamate and glutamine carbon. Ketone body metabolism also provides acetyl-CoA to the citrate synthetase reaction, in the process consuming oxaloacetate and thereby diminishing the transamination of glutamate to aspartate, a pathway in which oxaloacetate is a reactant. Relatively more glutamate then is available to the glutamate decarboxylase reaction, which increases brain [GABA]. Ketosis also increases brain [GABA] by increasing brain metabolism of acetate, which glia convert to glutamine. GABA-ergic neurons readily take up the latter amino acid and use it as a precursor to GABA. Ketosis also may be associated with altered amino acid transport at the blood-brain barrier. Specifically, ketosis may favor the release from brain of glutamine, which transporters at the blood-brain barrier exchange for blood leucine. Since brain glutamine is formed in astrocytes from glutamate, the overall effect will be to favor the release of glutamate from the nervous system.

Effect of Low and High Fat Diets on Nutrient Intakes and Selected Cardiovascular Risk Factors in Sedentary Men and Women

Reference:
Meksawan, K., Pendergast, D.R., Leddy, J.J., et al., "Effect of Low and High Fat Diets on Nutrient Intakes and Selected Cardiovascular Risk Factors in Sedentary Men and Women," Journal of the American College of Nutrition, 23(2), 2004, pages 131-140.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

OBJECTIVE: The desired level of dietary fat intake is controversial. The effect of decreasing fat intake to 19% and increasing it to 50% from a control diet of 30% on nutritional status and cardiovascular risk factors in healthy individuals was studied.

METHODS: Eleven healthy subjects (5 men and 6 women) were randomized to consume diets with 19% and 50% calories from fat. Each diet lasted 3 weeks, with a one-week washout. The habitual and washout diets were determined to be 30% fat. At the beginning and the end of each diet, fasting blood was collected to determine plasma lipoproteins, and physiological factors were measured.

RESULTS: Total caloric expenditure was similarly balanced to intake on the 30% and 50% fat diets, but intake was significantly lower on the 19% fat diet and led to a loss of 0.6 kg body weight. Consumptions of essential fatty acids, vitamin E and zinc were improved with increased fat intake, but folate intake was compromised on the 30% and 50% fat diets. Compared with the 50% fat diet, subjects consuming the 19% fat diet had significantly lower HDL cholesterol (HDL-C) (54 +/- 3 vs. 63 +/- 3 mg. dL(-1), p  0.05) and apolipoprotein A1 (ApoA1) (118 +/- 4 vs. 127 +/- 3 mg/dL, p < 0.05). Changing the levels of fat intake did not affect % body fat, heart rate, blood pressure, blood triglycerides, total cholesterol (TC), LDL cholesterol, apolipoprotein B (ApoB), TC/HDL-C and ApoA1/ApoB ratios.

CONCLUSION: A low fat diet (19%) may not provide sufficient calories, essential fatty acids, and some micronutrients (especially vitamin E and zinc) for healthy untrained individuals, and it also lowered ApoA1 and HDL-C. Increasing fat intake to 50% of calories improved nutritional status, and did not negatively affect certain cardiovascular risk factors.

Increasing Refined Sugars in the American Diet Can Be Linked to U.S. Epidemic of Type 2 Diabetes

Reference:
Gross, L.S., Li, L., Ford, E.S., et al., "Increased Consumption of Refined Carbohydrates and the Epidemic of Type 2 Diabetes in the United States: An Ecological Assessment", American Journal of Clinical Nutrition, 79, 2004, pages 774-779.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

The incidence of type 2 diabetes in the U.S. has increased about 30 times during the past 40 years, concurrent with a 3-fold increase in the rates of obesity. More than 16 million Americans are now afflicted with this costly disease. Publishing in this month's American Journal of Clinical Nutrition, Dr. Gross and colleagues from the Harvard School of Public Health examined the relationship of the consumption of refined sugars in the U.S. diet to the prevalence of type 2 diabetes, using U.S. Department of Agriculture and Center for Disease Control statistics since the year 1909. Whereas the current consumption of carbohydrates, about 500 grams per day, is about the same as 100 years ago, the present diet emphasizes refined sugars as opposed to a previous reliance on whole grains. Their data analysis found positive correlations of the prevalence of type 2 diabetes with daily total calories, fat, and carbohydrate. After controlling for total calorie intake, there was a negative correlation of the incidence of type 2 diabetes with dietary fiber, while the strongest positive correlation was with the consumption of refined sugars, in particular, high-fructose corn syrup. These findings are consistent with the known linkage of refined high-fructose sugars to insulin resistance, which is at the metabolic core of type 2 diabetes. An accompanying editorial by Dr. Jenkins and colleagues puts these findings into the broader context of the relationship of the U.S. obesity epidemic with its parallel increase in the incidence of type 2 diabetes to the poor U.S. diet of too many total calories and too much refined sugars.

Comparison of a Very Low-Carbohydrate and Low-Fat Diet

Reference:
Volek, J.S., Sharman, M.J., Gomez, A.L., "Comparison of a Very Low-Carbohydrate and Low-Fat Diet on Fasting Lipids, LDL Subclasses, Insulin Resistance, and Postprandial Lipemic Responses in Overweight Women", Journal of the American College of Nutrition, 23(2), 2004, pages 177-184.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

OBJECTIVE: Very low-carbohydrate diets are widely used for weight loss yet few controlled studies have determined how these diets impact cardiovascular risk factors compared to more traditional low-fat weight loss diets. The primary purpose of this study was to compare a very low-carbohydrate and a low-fat diet on fasting blood lipids, LDL subclasses, postprandial lipemia, and insulin resistance in overweight and obese women.

METHODS: Thirteen normolipidemic, moderately overweight (body fat >30%) women were prescribed two hypocaloric (-500 kcal/day) diets for 4 week periods, a very low-carbohydrate (10% carbohydrate) and a low-fat (<30% fat) diet. The diets were consumed in a balanced and randomized fashion. Two fasting blood draws were performed on separate days and an oral fat tolerance test was performed at baseline, after the very low-carbohydrate diet, and after the low-fat diet.

RESULTS: Compared to corresponding values after the very low-carbohydrate diet, fasting total cholesterol, LDL-C, and HDL-C were significantly (p </= 0.05) lower, whereas fasting glucose, insulin, and insulin resistance (calculated using the homeostatic model assessment) were significantly higher after the low-fat diet. Both diets significantly decreased postprandial lipemia and resulted in similar nonsignificant changes in the total cholesterol/HDL-C ratio, fasting triacylglycerols, oxidized LDL, and LDL subclass distribution.

CONCLUSIONS: Compared to a low-fat weight loss diet, a short-term very low-carbohydrate diet did not lower LDL-C but did prevent the decline in HDL-C and resulted in improved insulin sensitivity in overweight and obese, but otherwise healthy women. Small decreases in body mass improved postprandial lipemia, and therefore cardiovascular risk, independent of diet composition.

Commentary:

The following information was written by Atkins professionals.

Overweight women with normal blood lipid profiles lost significantly more weight on a reduced calorie, low carbohydrate diet than on a low fat diet after four weeks. Although the low carb diet did not lower LDL cholesterol, it did prevent a decline in HDL cholesterol that was seen in following a low fat diet. Both diets improved multiple risk factors for heart disease. The low carb group had lower levels of blood sugar, insulin, and insulin resistance compared to the low fat diet. The results suggest that a short-term low carbohydrate diet results in greater weight loss than a low fat diet, without adverse effects on heart disease risk.

Very Low-Carbohydrate and Low-Fat Diets Affect Lipids

Reference:
Sharman, M.J., Gomez, A.L., Kraemer, W.J., et al., "Very Low-Carbohydrate and Low-Fat Diets Affect Fasting Lipids and Postprandial Lipemia Differently in Overweight Men," Journal of Nutrition, 134(4), 2004, pages 880-885.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

Hypoenergetic very low-carbohydrate and low-fat diets are both commonly used for short-term weight loss; however, few studies have directly compared their effect on blood lipids, with no studies to our knowledge comparing postprandial lipemia, an important independently identified cardiovascular risk factor. The primary purpose of this study was to compare the effects of a very low-carbohydrate and a low-fat diet on fasting blood lipids and postprandial lipemia in overweight men. In a balanced, randomized, crossover design, overweight men (n = 15; body fat >25%; BMI, 34 kg/m(2)) consumed 2 experimental diets for 2 consecutive 6-wk periods. One was a very low-carbohydrate (<10% energy as carbohydrate) diet and the other a low-fat (<30% energy as fat) diet. Blood was drawn from fasting subjects on separate days and an oral fat tolerance test was performed at baseline, after the very low-carbohydrate diet period, and after the low-fat diet period. Both diets had the same effect on serum total cholesterol, serum insulin, and homeostasis model analysis-insulin resistance (HOMA-IR). Neither diet affected serum HDL cholesterol (HDL-C) or oxidized LDL (oxLDL) concentrations. Serum LDL cholesterol (LDL-C) was reduced (P < 0.05) only by the low-fat diet (-18%). Fasting serum triacylglycerol (TAG), the TAG/HDL-C ratio, and glucose were significantly reduced only by the very low-carbohydrate diet (-44, -42, and -6%, respectively). Postprandial lipemia was significantly reduced when the men consumed both diets compared with baseline, but the reduction was significantly greater after intake of the very low-carbohydrate diet. Mean and peak LDL particle size increased only after the very low-carbohydrate diet. The short-term hypoenergetic low-fat diet was more effective at lowering serum LDL-C, but the very low-carbohydrate diet was more effective at improving characteristics of the metabolic syndrome as shown by a decrease in fasting serum TAG, the TAG/HDL-C ratio, postprandial lipemia, serum glucose, an increase in LDL particle size, and also greater weight loss (P < 0.05).

Commentary:

The following information was written by Atkins professionals.

A short-term very low carb, low calorie diet significantly improved biomarkers associated with the metabolic syndrome, including triglycerides and LDL particle size. In contrast, there were no significant improvements seen for biomarkers associated with the metabolic syndrome following compliance to a low fat, low calorie diet. Individuals also lost significantly more weight on the very low carb diet compared with the low fat diet.

Glycemic Index, Glycemic Load and Risk of Gastric Cancer

Reference:
Augustin, L.S., Gallus, S., Negri, E., et al., "Glycemic Index, Glycemic Load and Risk of Gastric Cancer", Annals of Oncology, 15(4), 2004, pages 581-584.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

BACKGROUND: Dietary carbohydrates have been directly associated with gastric cancer risk and have been considered general indicators of a poor diet. However, elevated levels of glucose and insulin elicited by consumption of high amounts of refined carbohydrates may stimulate mitogenic and cancer-promoting insulin-like growth factors (IGF). Glycemic index (GI) and glycemic load (GL), which represent indirect measures of dietary insulin demand, were analysed to understand further the association between carbohydrates and gastric cancer.

PATIENTS AND METHODS: Data were derived from a hospital-based case-control study on gastric cancer, conducted in Italy between 1985 and 1997, including 769 cases with incident, histologically confirmed gastric cancer and 2081 controls admitted to the same hospital network as cases for acute, non-neoplastic diseases. All subjects were interviewed using a reproducible food frequency questionnaire.

RESULTS: The multivariate odds ratios (OR) for subsequent quartiles of dietary GL were 1.44 [95% confidence interval (CI) 1.11-1.87], 1.62 (95% CI 1.24-2.12) and 1.94 (95% CI 1.47-2.55). No consistent pattern of risk was seen with GI. The associations were consistent in different strata of age, education and body mass index, and were stronger in women.

CONCLUSIONS: This study supports the hypothesis of a direct association between GL and gastric cancer risk, thus providing an innovative interpretation, linked to excess circulating insulin and related IGFs, for the association between carbohydrates and risk of gastric cancer.

Effect on Dietary Protein Supplements on Calcium

Reference:
Dawson-Hughes, B., Harris, S.S., Rasmussen, H., et al., "Effect of Dietary Protein Supplements on Calcium Excretion in Healthy Older Men and Women", Journal of Clinical Endocrinology and Metabolism, 89(3), 2004, pages 1169-1173.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

Currently there is no consensus on the impact of dietary protein on calcium and bone metabolism. This study was conducted to examine the effect of increasing protein intake on urinary calcium excretion and to compare circulating levels of IGF-I and biochemical markers of bone turnover in healthy older men and women who consumed either a high or a low protein food supplement for 9 wk. Thirty-two subjects with usual protein intakes of less than 0.85 g/kg.d were randomly assigned to daily high (0.75 g/kg) or low (0.04 g/kg) protein supplement groups. Isocaloric diets were maintained by advising subjects to reduce their intake of carbohydrates. Selected biochemical measurements were made at baseline and on d 35 and either d 49 or 63. Changes in urinary calcium excretion in the two groups did not differ significantly over the course of the study. The high protein group had significantly higher levels of serum IGF-I (P = 0.008) and lower levels of urinary N-telopeptide (P = 0.038) over the period of d 35-49 or 63. We conclude that increasing protein intake from 0.78 to 1.55 g/kg.d with meat supplements in combination with reducing carbohydrate intake did not alter urine calcium excretion, but was associated with higher circulating levels of IGF-I, a bone growth factor, and lowered levels of urinary N-telopeptide, a marker of bone resorption. In contrast to the widely held belief that increased protein intake results in calcium wasting, meat supplements, when exchanged isocalorically for carbohydrates, may have a favorable impact on the skeleton in healthy older men and women.

A Pilot Trial of a Low-Carbohydrate, Ketogenic Diet

Reference:
Yancy, W.S., Vernon, M.C., Westman. E.C., "A Pilot Trial of a Low-Carbohydrate, Ketogenic Diet in Patients with Type 2 Diabetes", Metabolic Syndrome and Related Disorders, 1(3), 2003, pages 239-243.

Summary:

The full text aticle is available at liebertpub and was not written by Atkins professionals.

Commentary:

The following information was written by Atkins professionals.

Men with type 2 diabetes had significant reductions in body weight, waist circumference, body fat, blood pressure, and heart rate after following Induction and proceeding to OWL for a total of 16 weeks. Blood sugar control also improved. These results suggest that a short-term, low carbohydrate diet may reduce risk of the metabolic syndrome and improve blood sugar control in overweight men with type 2 diabetes.

Clinical Experience of a Carbohydrate-Restricted Diet: Effect on Diabetes

Reference:
Vernon, M.C., Mavropoulos, J., Transue, M., et al., "Clinical Experience of a Carbohydrate-Restricted Diet: Effect on Diabetes Mellitus", Metabolic Syndrome and Related Disorders, 1(3), 2003, pages 233-237. 

Summary:

The following information is available from the publisher at liebertpub and was not written by Atkins professionals.

Commentary:

The following information was written by Atkins professionals.

Women with type 2 diabetes who were compliant with Induction and OWL lost an average of 10% of their body weight after two months. There were significant improvements in triglycerides, and also significant improvements in long-term blood sugar control, with half of the readings normalized to non-diabetic levels.These results indicate how beneficial a low carb diet can be for individuals with type 2 diabetes.

Clinical Use of a Carbohydrate-Restricted Diet

Reference:
Hickey, J.T., Hickey, L., Yancy, W.S., et al., "Clinical Use of a Carbohydrate-Restricted Diet to Treat the Dyslipidemia of the Metabolic Syndrome", Metabolic Syndrome and Related Disorders, 2003, 1(3), pages 227-232.

Summary:

The following information is available at liebertpub and was not written by Atkins professionals.

Background: The metabolic syndrome is characterized by an atherogenic dyslipidemia identifiable using lipoprotein subclass analysis. This study assesses the effect of a carbohydrate-restricted diet on the dyslipidemia of the metabolic syndrome in a clinical setting.

Methods: This is a retrospective chart review of patients attending a preventive medicine clinic using lipoprotein subclass analysis (by NMR spectroscopy) to identify the atherogenic dyslipidemia. If present, patients were counseled to begin a carbohydrate-restricted diet (< 20 g/day). Patients already on statin therapy were included only if the medication dose was not changed. The outcomes were changes in body weight, fasting serum lipid profiles and serum lipoprotein subclasses.

Results: Of 122 patients identified, 80 patients had complete pre- and post-treatment data. The mean (±SD) age was 66 ± 9 years, baseline weight was 85 ± 12 kg, BMI was 28.1 ± 3.6, 73% were male, 99% were Caucasian. Sixty-five percent were taking statin medication. Carbohydrate-restriction led to a 13% reduction in total cholesterol, 16% reduction in LDL cholesterol, 38% reduction in triglycerides, and a 13% increase in HDL cholesterol (all p values < 0.001). Carbohydrate-restriction also led to a reduction in LDL particle concentration of 28%, a reduction in small LDL of 82%, a reduction of large VLDL of 62%, and an increase in large HDL of 30% (all p values < 0.001).

Conclusions: A carbohydrate-restricted diet recommendation led to improvements in lipid profiles and lipoprotein subclass traits of the metabolic syndrome in a clinical outpatient setting, and should be considered as a treatment for the metabolic syndrome.  This is a retrospective chart review of patients attending a preventive medicine clinic using lipoprotein subclass analysis (by NMR spectroscopy) to identify the atherogenic dyslipidemia. If present, patients were counseled to begin a carbohydrate-restricted diet (< 20 g/day). Patients already on statin therapy were included only if the medication dose was not changed. The outcomes were changes in body weight, fasting serum lipid profiles and serum lipoprotein subclasses.

Calorie Diet on the Treatment of Childhood Obesity

Reference:
Bailes, J.R., Strow, M.T., Werthammer, J., et al., "Effect of Low-Carbohydrate, Unlimited Calorie Diet on the Treatment of Childhood Obesity: A Prospective Controlled Study", Metabolic Syndrome and Related Disorders, 1(3), 2003, pages 221-225.

Summary:

The following information is available from the publisher at liebertpub and was not written by Atkins professionals.

Commentary:

The following information was written by Atkins professionals.

Obese children lost weight after two months of consuming a carbohydrate-restricted diet (less than 30 grams per day) that allowed unlimited calories, protein, and fat, while obese children instructed to follow a calorie restricted, higher carbohydrate diet (55% of total calories) gained weight. These results suggest that over a short-term period, a low carbohydrate, high protein, unrestricted calorie diet may be superior to a low fat, low calorie diet in producing weight loss. The authors concluded a high rate of compliance was achieved on the low carb, unrestricted calorie diet as indicated by improvements in weight. Since compliance is a major barrier to achieving and maintaining weight loss, this suggests that a low carb diet may be a good option for individuals who have not been able to follow and stick to other diets.

Treatment of Type 2 Diabetes in Childhood Using a Very-Low-Calorie Ketogenic Diet

Reference:
Willi, S.M., Martin, K., Datko, F.M., et al., "Treatment of Type 2 Diabetes in Childhood Using a Very-Low-Calorie Diet", Diabetes Care, 27(2), 2004, pages 348-353.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

OBJECTIVE:-Pharmacologic agents currently approved for use in children with type 2 diabetes (metformin and insulin) are less than optimal for some patients. We evaluated the use of a ketogenic, very-low-calorie diet (VLCD) in the treatment of type 2 diabetes.

RESEARCH DESIGN AND METHODS-We conducted a chart review of 20 children (mean age 14.5 +/- 0.4 years) who consumed a ketogenic VLCD in the treatment of type 2 diabetes. Several response variables (BMI, blood pressure, HbA(1c), blood glucose, and treatment regimens) were examined before, during, and up to 2 years after the diet and compared with a matched diabetic control group.

RESULTS:-Before starting the diet, 11 of 20 patients were treated with insulin and 6 with metformin. Mean daily blood glucose values fell from 8.9 +/- 1.1 to 5.5 +/- 0.38 mmol/l (P  0.0001) in the first 3 days of the VLCD, allowing insulin and oral agents to be discontinued in all but one subject. BMI fell from 43.5 +/- 1.8 to 39.3 +/- 1.8 kg/m(2) (P < 0.0001) and HbA(1c) dropped from 8.8 +/- 0.6 to 7.4 +/- 0.6% (P < 0.005) as the diet was continued for a mean of 60 +/- 8 days (range 4-130 days), and none required resumption of antidiabetic medications. Sustained decreases in BMI and insulin requirements were observed in patients remaining on the VLCD for at least 6 weeks when compared with those of the control group.

CONCLUSIONS:-The ketogenic VLCD is an effective short-term, and possibly long-term, therapy for pediatric patients with type 2 diabetes. Blood glucose control and BMI improve, allowing the discontinuation of exogenous insulin and other antidiabetic agents. This diet, although strict, has potential as an alternative to pharmacologic therapies for this emerging subset of diabetic individuals.

Efficacy of the Atkins Diet as Therapy for Intractable Epilepsy

Reference:
Kossoff, E.H., Krauss, G.L., McGrogan, J.R., et al., "Efficacy of the Atkins Diet as Therapy for Intractable Epilepsy", Neurology,  61(12), 2003, pages 1789-1791.

Summary:

The following information is available at Pub Med and was not written by Atkins professionals.

The ketogenic diet is effective for treating seizures in children with epilepsy. The Atkins diet can also induce a ketotic state, but has fewer protein and caloric restrictions, and has been used safely by millions of people worldwide for weight reduction. Six patients, aged 7 to 52 years, were started on the Atkins diet for the treatment of intractable focal and multifocal epilepsy. Five patients maintained moderate to large ketosis for periods of 6 weeks to 24 months; three patients had seizure reduction and were able to reduce antiepileptic medications. This provides preliminary evidence that the Atkins diet may have a role as therapy for patients with medically resistant epilepsy.

Commentary:

The following information was written by Atkins professionals.

A ketogenic diet (a very high fat diet) has been used to treat epilepsy in children. However, this diet is also associated with several diet restrictions including calories and protein. This study evaluated whether Induction would be an effective alternative for the usual ketogenic diet used. Six adolescents with epilepsy followed Induction for different lengths of time (less than two months to over 20 months). Results indicated that Induction has the potential to be an effective treatment to reduce seizures in patients with epilepsy.