The glycemic response (or glycaemic response) to a food or meal is the effect that food or meal has on blood sugar (glucose) levels after consumption. [1] It is normal for blood glucose and insulin levels to rise after eating and then return again to fasting levels over a short period of time. This is particularly so after consumption of meals rich in certain carbohydrates. Glycemic management refers to the selection of foods to manage your blood sugar levels.
Several tools have been developed to help quantify and communicate the effect of food on glycemic response. These include glycemic index (GI), glycemic load (GL) and glycemic glucose equivalents (GGE). A comparative glycemic response can also be determined, which compares the impact on blood glucose of one food to another based upon their total carbohydrate or total quantity.
In 1981, the idea of classifying carbohydrates according to their Glycemic Index was first published. Since then, many studies have been undertaken to determine the impact of altering the blood glucose-raising potential (glycemic challenge) of the diet on a wide range of short- and long-term health outcomes. However, evaluating the impact of a single dietary change on health is notoriously complex, and opinions on the relevance of GI, GL and GGE have been divided. There are many different ways of lowering glycemic response, GI or GL, not all of which have the same effects on health. ILSI Europe published a monograph in November 2011 titled "Food, Glycaemic Response and Health", which concluded that "it is becoming evident that modifying the glycemic response of the diet should not be seen as a stand-alone strategy but rather as an element of an overall balanced diet and lifestyle".
A low glycemic food will release glucose more slowly and steadily, which leads to lower postprandial (after meal) blood glucose readings. A high glycemic food causes a more rapid rise in blood glucose levels after meals. High glycemic foods are ideal for energy recovery after exercise or for a person experiencing hypoglycemia.
The glycemic effect of foods depends on a number of factors such as the type of starch (amylose versus amylopectin), physical entrapment of the starch molecules within the food, fat and protein content of the food and organic acids or their salts in the meal — adding vinegar, for example, will lower the glycemic response. The presence of fat or soluble dietary fiber can slow the gastric emptying rate, thus lowering the glycemic response. In general, foods with higher amounts of fiber and/or resistant starch have a lower glycemic response.
While adding fat or protein will lower the glycemic response to a meal, the relative differences remain. That is, with or without additions, there is still a higher blood glucose curve after a high glycemic white bread than after a low glycemic bread such as pumpernickel.
Unrefined wild plant foods like those available to contemporary foragers typically exhibit low glycemic indices. [2]
A carbohydrate is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 and thus with the empirical formula Cm(H2O)n, which does not mean the H has covalent bonds with O. However, not all carbohydrates conform to this precise stoichiometric definition, nor are all chemicals that do conform to this definition automatically classified as carbohydrates.
Dietary fiber or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes. Dietary fibers are diverse in chemical composition and can be grouped generally by their solubility, viscosity and fermentability which affect how fibers are processed in the body. Dietary fiber has two main components: soluble fiber and insoluble fiber which are components of plant-based foods such as legumes, whole grains, cereals, vegetables, fruits, and nuts or seeds. A diet high in regular fiber consumption is generally associated with supporting health and lowering the risk of several diseases. Dietary fiber consists of non-starch polysaccharides and other plant components such as cellulose, resistant starch, resistant dextrins, inulin, lignins, chitins, pectins, beta-glucans, and oligosaccharides.
The glycemic (glycaemic) index is a number from 0 to 100 assigned to a food, with pure glucose arbitrarily given the value of 100, which represents the relative rise in the blood glucose level two hours after consuming that food. The GI of a specific food depends primarily on the quantity and type of carbohydrate it contains, but is also affected by the amount of entrapment of the carbohydrate molecules within the food, the fat and protein content of the food, the amount of organic acids in the food, and whether it is cooked and, if so, how it is cooked. GI tables, which list many types of foods and their GIs, are available. A food is considered to have a low GI if it is 55 or less; high GI if 70 or more; and mid-range GI if 56 to 69.
Low-carbohydrate diets restrict carbohydrate consumption relative to the average diet. Foods high in carbohydrates are limited, and replaced with foods containing a higher percentage of fat and protein, as well as low carbohydrate foods.
The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate dietary therapy that in conventional medicine is used mainly to treat hard-to-control (refractory) epilepsy in children. The diet forces the body to burn fats rather than carbohydrates.
Maltodextrin is a name shared by two different families of chemicals. Both families are glucose polymers, but have little chemical or nutritional similarity.
The glycemic load (GL) of food is a number that estimates how much the food will raise a person's blood glucose level after it is eaten. One unit of glycemic load approximates the effect of eating one gram of glucose. Glycemic load accounts for how much carbohydrate is in the food and how much each gram of carbohydrate in the food raises blood glucose levels. Glycemic load is based on the glycemic index (GI), and is calculated by multiplying the weight of available carbohydrate in the food (in grams) by the food's glycemic index, and then dividing by 100.
Tagatose is a hexose monosaccharide. It is found in small quantities in a variety of foods, and has attracted attention as an alternative sweetener. It is often found in dairy products, because it is formed when milk is heated. It is similar in texture and appearance to sucrose :215 and is 92% as sweet,:198 but with only 38% of the calories.:209 Tagatose is generally recognized as safe by the Food and Agriculture Organization and the World Health Organization, and has been since 2001. Since it is metabolized differently from sucrose, tagatose has a minimal effect on blood glucose and insulin levels. Tagatose is also approved as a tooth-friendly ingredient for dental products. Consumption of more than about 30 grams of tagatose in a dose may cause gastric disturbance in some people, as it is mostly processed in the large intestine, similar to soluble fiber.:214
Resistant starch (RS) is starch, including its degradation products, that escapes from digestion in the small intestine of healthy individuals. Resistant starch occurs naturally in foods, but it can also be added as part of dried raw foods, or used as an additive in manufactured foods.
Phosphated distarch phosphate, is a type of chemically modified starch. It can be derived from wheat starch, tapioca starch, potato starch or many other botanical sources of starch. It is produced by replacing the hydrogen bonds between starch chains by stronger, covalent phosphate bonds that are more permanent. It is manufactured by treating starch with sodium tripolyphosphate (STPP) and sodium trimetaphosphate (STMP), or phosphoryl chloride (POCl3). Phosphorylated cross-linked starches is a category of modified food starches within the U.S. Code of Federal Regulations. Starches treated with STMP and STPP must not exceed 0.4 percent phosphorus as residual phosphate.
Isomaltulose is a disaccharide carbohydrate composed of glucose and fructose. It is naturally present in honey and sugarcane extracts and is also produced industrially from table sugar (sucrose) and used as a sugar alternative.
The Montignac diet is a high-protein low-carbohydrate fad diet that was popular in the 1990s, mainly in Europe. It was invented by Frenchman Michel Montignac (1944–2010), an international executive for the pharmaceutical industry, who, like his father, was overweight in his youth. His method is aimed at people wishing to lose weight efficiently and lastingly, reduce risks of heart failure, and prevent diabetes.
The insulin index of food represents how much it elevates the concentration of insulin in the blood during the two-hour period after the food is ingested. The index is similar to the glycemic index (GI) and glycemic load (GL), but rather than relying on blood glucose levels, the Insulin Index is based upon blood insulin levels. The Insulin Index represents a comparison of food portions with equal overall caloric content, while GI represents a comparison of portions with equal digestible carbohydrate content and the GL represents portions of a typical serving size for various foods. The Insulin Index can be more useful than either the glycemic index or the glycemic load because certain foods cause an insulin response despite there being no carbohydrates present, and some foods cause a disproportionate insulin response relative to their carbohydrate load.
A diabetic diet is a diet that is used by people with diabetes mellitus or high blood sugar to minimize symptoms and dangerous complications of long-term elevations in blood sugar.
Dietary Reference Values (DRV) is the name of the nutritional requirements systems used by the United Kingdom Department of Health and the European Union's European Food Safety Authority.
The South Beach Diet is a popular fad diet developed by Arthur Agatston and promoted in his bestselling 2003 book. It emphasizes eating food with a low glycemic index, and categorizes carbohydrates and fats as "good" or "bad". Like other fad diets, it may have elements which are generally recognized as sensible, but it promises benefits not backed by supporting evidence or sound science.
Weight management refers to behaviors, techniques, and physiological processes that contribute to a person's ability to attain and maintain a healthy weight. Most weight management techniques encompass long-term lifestyle strategies that promote healthy eating and daily physical activity. Moreover, weight management involves developing meaningful ways to track weight over time and to identify the ideal body weights for different individuals.
Isomaltooligosaccharide (IMO) is a mixture of short-chain carbohydrates which has a digestion-resistant property. IMO is found naturally in some foods, as well as being manufactured commercially. The raw material used for manufacturing IMO is starch, which is enzymatically converted into a mixture of isomaltooligosaccharides.
Oat β-glucans are water-soluble β-glucans derived from the endosperm of oat kernels known for their dietary contribution as components of soluble fiber. Due to their property to lower serum total cholesterol and low-density lipoprotein cholesterol, and potentially reduce the risk of cardiovascular diseases, oat β-glucans have been assigned a qualified health claim by the European Food Safety Authority and the US Food and Drug Administration.
High performance sport dogs are those bred and trained to compete in various athletic events. Events include but are not limited to, agility trials, hunting and racing. These events are physically and metabolically demanding. As a result, canine athletes require specialized nutrition in order to perform at high levels during events and for maintenance and recovery. The main nutritional concern for sport dogs is adequate energy. A well-balanced diet, containing the appropriate amounts of protein, fat, carbohydrate, fiber and micronutrients is essential to meet these energy requirements.