A typical low-carb diet provides between about 20 to 150 g of carbohydrates a day, compared to the average of 300 g a day consumed by most Americans. To lower your carb intake, food groups rich in carbohydrates, mainly grains, starchy vegetables, legumes, fruits and sugary foods, need to be eliminated or considerably limited. While these foods constitute the foundation and provide more than half of the calories on a standard American diet, a low-carb diet focuses on non-starchy vegetables, protein-rich foods, such as eggs, meat, poultry, fish, seafood and cheese, as well as fats, from mayo, butter, cream, vegetable oils, coconut, avocado, nuts, nut butter and seeds.
Saturated Fat and Cholesterol
Critics of the low-carb way of eating often claim that low-carb diets are rich in "artery-clogging" saturated fats. Some low-carb diets may be rich in saturated fats, especially if they are based on butter, mayo, cream, fatty meat and full-fat cheese, although it is not always the case, for example, if the low-carb plan is based on lean meat, poultry, fish, seafood and monounsaturated fats from olive oil, avocado, nuts and seeds. Moreover, the phrase "artery-clogging" saturated fat needs to be revised in view of the new light shed on the subject by a rigorous meta-analysis published in January 2010 in the "American Journal of Clinical Nutrition" showing that saturated fats are not associated with an increased risk of developing heart disease.
LDL Cholesterol
LDL cholesterol levels, often referred to as the bad cholesterol, are usually left unchanged when following a low-carb diet. The type of saturated fat predominantly found in animal meat, called stearic acid, as well as the most abundant saturated fat in the American diet, palmitic acid, have repeatedly been shown not to raise LDL cholesterol levels, according to a paper published in August 2005 in "Nutrition & Metabolism." In addition, low-carb diets are associated with large, fluffy LDL particles, which are less likely to form plaque compared to small, dense LDL particles.
HDL Cholesterol
HDL cholesterol, known as the good cholesterol, is protective against heart disease and levels above 60 mg/dL are recommended for both men and women. Most diets, especially when they lead to successful weight loss, are associated with a decrease in HDL cholesterol levels. For example, in a study published in May 2004 in "Annals of Internal Medicine," participants following a low-fat and calorie-restricted diet for 24 weeks had their HDL cholesterol reduced by 1.6 mg/dL. On the other hand, low-carb diets help maintain and even boost your heart-protective HDL cholesterol levels. In the same study, participants in the low-carb group increased their HDL concentrations by 5.6 mg/dL.
Triglycerides
Triglycerides are not cholesterol, but rather a type of fat circulating in your blood that constitutes another important predictor for estimating your cardiovascular risk. Although a low-fat diet may slightly help you reduce your triglycerides, low-carb diets are significantly more effective at lowering these levels. For example, subjects following a low-carb eating plan for 24 weeks reduced their triglycerides by 74.2 mg/dL, compared to a decrease of 27.9 mg/dL in the low-fat group, as published in the May 2004 issue of the "Annals of Internal Medicine."
References
- "American Journal of Clinical Nutrition"; Meta-Analysis of Prospective Cohort Studies Evaluating the Association of Saturated Fat With Cardiovascular Disease; Patty W Siri-Tarino et al.; January 2010
- "Nutrition & Metabolism"; The Case for Not Restricting Saturated Fat on a Low Carbohydrate Diet; Jeff S. Volek, et al.; August 2005
- "Annals of Internal Medicine"; A Low-Carbohydrate, Ketogenic Diet versus a Low-Fat Diet to Treat Obesity and Hyperlipidemia; William S. Yancy Jr., et al.; 2004
- "Nutrition & Metabolism"; The Case for Low Carbohydrate Diets in Diabetes Management; Surender K. Arora, et al.; July 2005
Member Comments