Both low-glycemic and low-carb diets pertain to the carbohydrates you include in your meals. The principle behind a low-carb diet is to limit your carbohydrate consumption, reduce your insulin production and facilitate fat loss. On this diet, you eliminate or restrict carbohydrates-rich foods, such as grains, starchy vegetables, fruits, some dairy and sugar. Low-glycemic diets, on the other hand, are based on low-GI carbohydrates, which help prevent big swings in your blood sugar and insulin levels.
Carbohydrate Intake
The 2010 Dietary Guidelines for Americans recommends you get 45 to 65 percent, or about half, of your calories from carbohydrates, or 225 to 325 g of carbohydrates a day based on a 2,000-calorie diet. If you follow a low-glycemic diet, your total carbohydrate intake can fall within this range. But if you follow a low-carb diet, your daily carb intake will be below 100 g a day, and sometimes even below 20 g a day during the initial phases.
Types of Carbohydrates
Low-GI diets emphasize the selection of good quality carbohydrates, which are defined by a glycemic index value of 55 or below. You digest and absorb low-glycemic carbohydrates at a slower pace, keeping your blood sugar and insulin levels more stable between meals. On this diet, you avoid high-GI foods, which have a glycemic index value of 70 and above, because they quickly and significantly elevate your blood sugar levels. You can consume medium-GI carbohydrates, which have a glycemic index value between 56 and 69, in moderation. With low-carb diets, all carbs are restricted, whether ithey are refined grains, whole grains, fruits, soft drinks, desserts or starchy vegetables.
Health Benefits
Both low-carb and low-glycemic diets are associated with significant health benefits. For example, low-carb diets can lead to substantial body fat loss in addition to lowering triglycerides and boosting HDL cholesterol levels, reducing the risk of developing cardiovascular diseases, according to a study published in May 2004 in "Annals of Internal Medicine." Low-carb diets are also associated with improved diabetes management, according to the authors of a paper published in July 2005 in "Nutrition & Metabolism." Low-GI diets are associated with a healthier body weight, improved diabetes control, a lower risk of developing cardiovascular diseases and improved athletic performance.
Health Risks
Both low-carb and low-glycemic diets are both safe. Although low-carb diets were once critiqued for their high saturated fat content, it is now generally accepted that saturated fats are not the villain in cardiovascular disease, according to a January 2010 meta-analysis published in "American Journal of Clinical Nutrition." Moreover, although low-carb diets are higher in fat, the type of fat depends on your food choices. A low-carb diet rich in butter, mayonnaise, cream, bacon, lard and fatty meat can be high in saturated fat, while one rich in fish, olive oil, avocado and nuts would be high in unsaturated fats.
Low-glycemic diets do not have side effects, but low-carb dieters may experience unpleasant symptoms, such as headaches, constipation, fatigue, lethargy and irritability, in the first few days. These symptoms are not harmful and resolve by themselves after a few days; they stem from carbohydrate withdrawal and the adaptation your body goes through to start burning fat instead of carbohydrates as its main source of energy.
Food Choices
The food choices available on a low-carb or a low-glycemic diet differ greatly. On a low-carb diet, you need to limit or cut out breads, rice, pasta, potatoes, fruits, sugar, milk and yogurt. The main foods allowed on a low-carb diet include non-starchy vegetables, protein from eggs, meat, poultry, fish, seafood, cheese and tofu, as well as fat from vegetable oils, nuts, seeds, avocado, butter and cream. If you follow a low-glycemic diet, you will need to replace high-GI carbohydrates, such as most breakfast cereals and breads, white rice, granola bars, crackers and desserts, with low-GI options, such as sourdough bread, whole-grain pasta, Basmati rice, quinoa, barley, legumes and temperate-climate fruits. Accompany these low-glycemic carbohydrates with lean protein and small amounts of healthy fats from olive oil, canola oil, avocado, nuts and seeds.
References
- USDA and U.S. Department of Health and Human Services; 2010 Dietary Guidelines for Americans; January 2011
- University of Sydney: The Glycemic Index
- Mayo Clinic; Low-Carb Diet; May 2010
- "The New Atkins for a New You"; Eric C. Westman, et al.; 2010
- "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 and Samy I. McFarlane; July 2005
Member Comments