Low Glycemic Diet
A low-glycemic diet is one made up of low-glycemic foods.
The glycemic index is a way to measure the impact a food source of carbohydrate has on blood sugar. Formerly, carbohydrate foods are classified into simple and complex. Simple carbohydrates are those constituted by some carbohydrate molecules, while polysaccharides are more complex compounds that require further work of the digestive system to be digested and absorbed.
Polysaccharides tend to slower raise postprandial glycemia (blood glucose measured after eating), while simple carbohydrates to be digested and absorbed faster and raise blood sugar as peak, then decrease to baseline levels.
However, analyzing the type of carbohydrate and source food, it was observed that some simple carbohydrates such as fructose, had a reduced ability to increase blood sugar.
Although the amount of carbohydrates is also a parameter influencing the rise in blood glucose, there are other factors to consider.
Thus, the glycemic index emerges as a new way of analyzing foods based on their metabolic impact.
A low GI diet is an eating plan consisting of foods that maintain stable blood sugar levels and prevent the sharp rise in glucose and insulin after eating.
The glycemic index is not a food plan itself, but a tool used in order to select the most suitable food from the metabolic point of view and according to the objective of the individual.
The term glycemic index diet is used to refer to a food plan in which the glycemic index is used to plan and select meals.
An example of a low glycemic index diet may be the Zone diet. Such diets do not take into account the portion sizes, but the metabolic impact of food consumed.
To explain it in a simplified way, it can be said that the glycemic index is a number that arises from measuring the impact of a food portion with 50 grams of net carbohydrates (total carbohydrates – fiber) on blood glucose 2 hours after intake. This number gives us an idea of how quickly our body digests and absorbs the glucose molecules found in that food. Thus, two foods with the same amount of carbohydrates can have a very different impact on blood sugar.
The glycemic index value of a food can be classified into three categories:
Low glycemic index: 1-55.
Medium glycemic index: 56-69.
High glycemic index: 70 or more.
It is important to note that if a large amount of a low glycemic index food is consumed, the raise of blood glucose will be greater than if a higher glycemic index food is consumed, but in smaller amounts.
It is for this reason that many times the glycemic load is also used to analyze the impact of a meal on metabolism.
The glycemic load of a meal takes into account not only the glycemic index but also the amount of carbohydrates it provides.
The glycemic index may be used in different situations. Generally, it was used to design diets for diabetics. However, today many dietitians use the glycemic index for weight loss.
The sharp rise in blood glucose does not promote fat loss for three reasons:
– Increases insulin levels, anabolic hormone that stimulates fat storage.
– Causes a rapid decrease in glucose, even leading to hypoglycemia (glucose below the appropriate level) that stimulates appetite and intake of sweet foods.
– Destabilized blood glucose leads to low levels of energy and constant tiredness.
For these reasons, it is recommended that people who want to lose weight, maintain stable levels of insulin and glucose to promote fat loss and healthy energy levels.
What is a low glycemic diet
Then, what is a low-glycemic diet?
It is a diet plan that encourages a metabolic environment conducive to weight loss.
The glycemic index for weight loss is a new approach to analyze food, beyond calories and macronutrients, but broadens the vision and takes into account the metabolic variables that influence fat loss, as the concentrations of glucose and insulin in blood.
A plan that favors:
– Stable blood glucose concentrations.
– Reduction of insulin levels.
– Steadily fat loss.
– Stable energy levels and vitality.
– Reduction of food intake.
– A proper mood, avoiding the typical irritability of restricted eating plans.
– A decrease of binge eating and cravings for sweet foods.
Low glycemic foods
This is a list of low glycemic index foods.
All-bran (UK/Aus) 30
All-bran (US) 50
Oat bran 50
Rolled Oats 51
Special K (UK/Aus) 54
Natural Muesli 40
Soya and Linseed 36
Wholegrain Pumpernickel 46
Heavy Mixed Grain 45
Whole Wheat 49
Sourdough Rye 48
Sourdough Wheat 54
Frozen Green Peas 39
Frozen Sweet Corn 47
Raw Carrots 16
Boiled Carrots 41
Green Beans 15
Red Peppers 10
Wheat Pasta Shapes 54
New Potatoes 54
Meat Ravioli 39
Tortellini (Cheese) 50
Egg Fettuccini 32
Brown Rice 50
White long grain rice 50
Pearled Barley 22
Sweet Potatoes 48
Instant Noodles 47
Wheat tortilla 30
Snacks and sweet foods
Slim-Fast meal replacement 27
Snickers Bar (high fat) 41
Nut & Seed Muesli Bar 49
Sponge Cake 46
Milk Chocolate 42
Cashew Nuts 25
Nuts and Raisins 21
Corn Chips 42
Oatmeal Crackers 55
Peach, canned in natural juice 30
Dried Apricots 32
Coconut Milk 41
Kiwi Fruit 47
Kidney Beans (canned) 52
Butter Beans 36
Chick Peas 42
Haricot/Navy Beans 31
Lentils, Red 21
Lentils, Green 30
Pinto Beans 45
Blackeyed Beans 50
Yellow Split Peas 32
Whole milk 31
Skimmed milk 32
Chocolate milk 42
Sweetened yoghurt 33
Artificially Sweetened Yoghurt 23
Soy Milk 44
Low GI Foods have certain characteristics for which are beneficial to our metabolism:
– Contain dietary fiber: fiber, especially soluble fiber slows digestion of carbohydrates and reduces the arrival of sugars to the blood.
– Have a small amount of fat: healthy fats slow gastric emptying reducing time of arrival of sugars into the blood.
– They are natural and rich in water: The higher water content stimulates satiety and reduces food intake. In contrast, processed foods are digested quickly and cause blood glucose peak.
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